diff --git a/compiler/rustc_abi/src/callconv.rs b/compiler/rustc_abi/src/callconv.rs
index 872cae59a4e03..ee63e46e88c1d 100644
--- a/compiler/rustc_abi/src/callconv.rs
+++ b/compiler/rustc_abi/src/callconv.rs
@@ -6,9 +6,9 @@ mod abi {
 #[cfg(feature = "nightly")]
 use rustc_macros::HashStable_Generic;
 
-#[cfg(feature = "nightly")]
-use crate::{Abi, FieldsShape, TyAbiInterface, TyAndLayout};
 use crate::{Align, HasDataLayout, Size};
+#[cfg(feature = "nightly")]
+use crate::{BackendRepr, FieldsShape, TyAbiInterface, TyAndLayout};
 
 #[cfg_attr(feature = "nightly", derive(HashStable_Generic))]
 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
@@ -128,11 +128,11 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
     where
         Ty: TyAbiInterface<'a, C> + Copy,
     {
-        match self.abi {
-            Abi::Uninhabited => Err(Heterogeneous),
+        match self.backend_repr {
+            BackendRepr::Uninhabited => Err(Heterogeneous),
 
             // The primitive for this algorithm.
-            Abi::Scalar(scalar) => {
+            BackendRepr::Scalar(scalar) => {
                 let kind = match scalar.primitive() {
                     abi::Int(..) | abi::Pointer(_) => RegKind::Integer,
                     abi::Float(_) => RegKind::Float,
@@ -140,7 +140,7 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
                 Ok(HomogeneousAggregate::Homogeneous(Reg { kind, size: self.size }))
             }
 
-            Abi::Vector { .. } => {
+            BackendRepr::Vector { .. } => {
                 assert!(!self.is_zst());
                 Ok(HomogeneousAggregate::Homogeneous(Reg {
                     kind: RegKind::Vector,
@@ -148,7 +148,7 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
                 }))
             }
 
-            Abi::ScalarPair(..) | Abi::Aggregate { sized: true } => {
+            BackendRepr::ScalarPair(..) | BackendRepr::Memory { sized: true } => {
                 // Helper for computing `homogeneous_aggregate`, allowing a custom
                 // starting offset (used below for handling variants).
                 let from_fields_at =
@@ -246,7 +246,7 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
                     Ok(result)
                 }
             }
-            Abi::Aggregate { sized: false } => Err(Heterogeneous),
+            BackendRepr::Memory { sized: false } => Err(Heterogeneous),
         }
     }
 }
diff --git a/compiler/rustc_abi/src/layout.rs b/compiler/rustc_abi/src/layout.rs
index 86de39b8f9752..e6d66f608dae9 100644
--- a/compiler/rustc_abi/src/layout.rs
+++ b/compiler/rustc_abi/src/layout.rs
@@ -6,7 +6,7 @@ use rustc_index::Idx;
 use tracing::debug;
 
 use crate::{
-    Abi, AbiAndPrefAlign, Align, FieldsShape, HasDataLayout, IndexSlice, IndexVec, Integer,
+    AbiAndPrefAlign, Align, BackendRepr, FieldsShape, HasDataLayout, IndexSlice, IndexVec, Integer,
     LayoutData, Niche, NonZeroUsize, Primitive, ReprOptions, Scalar, Size, StructKind, TagEncoding,
     Variants, WrappingRange,
 };
@@ -125,7 +125,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 offsets: [Size::ZERO, b_offset].into(),
                 memory_index: [0, 1].into(),
             },
-            abi: Abi::ScalarPair(a, b),
+            backend_repr: BackendRepr::ScalarPair(a, b),
             largest_niche,
             align,
             size,
@@ -216,7 +216,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
         LayoutData {
             variants: Variants::Single { index: VariantIdx::new(0) },
             fields: FieldsShape::Primitive,
-            abi: Abi::Uninhabited,
+            backend_repr: BackendRepr::Uninhabited,
             largest_niche: None,
             align: dl.i8_align,
             size: Size::ZERO,
@@ -331,7 +331,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
 
             if let Ok(common) = common_non_zst_abi_and_align {
                 // Discard valid range information and allow undef
-                let field_abi = field.abi.to_union();
+                let field_abi = field.backend_repr.to_union();
 
                 if let Some((common_abi, common_align)) = common {
                     if common_abi != field_abi {
@@ -340,7 +340,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                     } else {
                         // Fields with the same non-Aggregate ABI should also
                         // have the same alignment
-                        if !matches!(common_abi, Abi::Aggregate { .. }) {
+                        if !matches!(common_abi, BackendRepr::Memory { .. }) {
                             assert_eq!(
                                 common_align, field.align.abi,
                                 "non-Aggregate field with matching ABI but differing alignment"
@@ -369,11 +369,11 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
         // If all non-ZST fields have the same ABI, we may forward that ABI
         // for the union as a whole, unless otherwise inhibited.
         let abi = match common_non_zst_abi_and_align {
-            Err(AbiMismatch) | Ok(None) => Abi::Aggregate { sized: true },
+            Err(AbiMismatch) | Ok(None) => BackendRepr::Memory { sized: true },
             Ok(Some((abi, _))) => {
                 if abi.inherent_align(dl).map(|a| a.abi) != Some(align.abi) {
                     // Mismatched alignment (e.g. union is #[repr(packed)]): disable opt
-                    Abi::Aggregate { sized: true }
+                    BackendRepr::Memory { sized: true }
                 } else {
                     abi
                 }
@@ -387,7 +387,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
         Ok(LayoutData {
             variants: Variants::Single { index: only_variant_idx },
             fields: FieldsShape::Union(union_field_count),
-            abi,
+            backend_repr: abi,
             largest_niche: None,
             align,
             size: size.align_to(align.abi),
@@ -434,23 +434,23 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 // Already doesn't have any niches
                 Scalar::Union { .. } => {}
             };
-            match &mut st.abi {
-                Abi::Uninhabited => {}
-                Abi::Scalar(scalar) => hide_niches(scalar),
-                Abi::ScalarPair(a, b) => {
+            match &mut st.backend_repr {
+                BackendRepr::Uninhabited => {}
+                BackendRepr::Scalar(scalar) => hide_niches(scalar),
+                BackendRepr::ScalarPair(a, b) => {
                     hide_niches(a);
                     hide_niches(b);
                 }
-                Abi::Vector { element, count: _ } => hide_niches(element),
-                Abi::Aggregate { sized: _ } => {}
+                BackendRepr::Vector { element, count: _ } => hide_niches(element),
+                BackendRepr::Memory { sized: _ } => {}
             }
             st.largest_niche = None;
             return Ok(st);
         }
 
         let (start, end) = scalar_valid_range;
-        match st.abi {
-            Abi::Scalar(ref mut scalar) | Abi::ScalarPair(ref mut scalar, _) => {
+        match st.backend_repr {
+            BackendRepr::Scalar(ref mut scalar) | BackendRepr::ScalarPair(ref mut scalar, _) => {
                 // Enlarging validity ranges would result in missed
                 // optimizations, *not* wrongly assuming the inner
                 // value is valid. e.g. unions already enlarge validity ranges,
@@ -607,8 +607,8 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 }
 
                 // It can't be a Scalar or ScalarPair because the offset isn't 0.
-                if !layout.abi.is_uninhabited() {
-                    layout.abi = Abi::Aggregate { sized: true };
+                if !layout.is_uninhabited() {
+                    layout.backend_repr = BackendRepr::Memory { sized: true };
                 }
                 layout.size += this_offset;
 
@@ -627,26 +627,26 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
             let same_size = size == variant_layouts[largest_variant_index].size;
             let same_align = align == variant_layouts[largest_variant_index].align;
 
-            let abi = if variant_layouts.iter().all(|v| v.abi.is_uninhabited()) {
-                Abi::Uninhabited
+            let abi = if variant_layouts.iter().all(|v| v.is_uninhabited()) {
+                BackendRepr::Uninhabited
             } else if same_size && same_align && others_zst {
-                match variant_layouts[largest_variant_index].abi {
+                match variant_layouts[largest_variant_index].backend_repr {
                     // When the total alignment and size match, we can use the
                     // same ABI as the scalar variant with the reserved niche.
-                    Abi::Scalar(_) => Abi::Scalar(niche_scalar),
-                    Abi::ScalarPair(first, second) => {
+                    BackendRepr::Scalar(_) => BackendRepr::Scalar(niche_scalar),
+                    BackendRepr::ScalarPair(first, second) => {
                         // Only the niche is guaranteed to be initialised,
                         // so use union layouts for the other primitive.
                         if niche_offset == Size::ZERO {
-                            Abi::ScalarPair(niche_scalar, second.to_union())
+                            BackendRepr::ScalarPair(niche_scalar, second.to_union())
                         } else {
-                            Abi::ScalarPair(first.to_union(), niche_scalar)
+                            BackendRepr::ScalarPair(first.to_union(), niche_scalar)
                         }
                     }
-                    _ => Abi::Aggregate { sized: true },
+                    _ => BackendRepr::Memory { sized: true },
                 }
             } else {
-                Abi::Aggregate { sized: true }
+                BackendRepr::Memory { sized: true }
             };
 
             let layout = LayoutData {
@@ -664,7 +664,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                     offsets: [niche_offset].into(),
                     memory_index: [0].into(),
                 },
-                abi,
+                backend_repr: abi,
                 largest_niche,
                 size,
                 align,
@@ -833,14 +833,14 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 end: (max as u128 & tag_mask),
             },
         };
-        let mut abi = Abi::Aggregate { sized: true };
+        let mut abi = BackendRepr::Memory { sized: true };
 
-        if layout_variants.iter().all(|v| v.abi.is_uninhabited()) {
-            abi = Abi::Uninhabited;
+        if layout_variants.iter().all(|v| v.is_uninhabited()) {
+            abi = BackendRepr::Uninhabited;
         } else if tag.size(dl) == size {
             // Make sure we only use scalar layout when the enum is entirely its
             // own tag (i.e. it has no padding nor any non-ZST variant fields).
-            abi = Abi::Scalar(tag);
+            abi = BackendRepr::Scalar(tag);
         } else {
             // Try to use a ScalarPair for all tagged enums.
             // That's possible only if we can find a common primitive type for all variants.
@@ -864,8 +864,8 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                         break;
                     }
                 };
-                let prim = match field.abi {
-                    Abi::Scalar(scalar) => {
+                let prim = match field.backend_repr {
+                    BackendRepr::Scalar(scalar) => {
                         common_prim_initialized_in_all_variants &=
                             matches!(scalar, Scalar::Initialized { .. });
                         scalar.primitive()
@@ -934,7 +934,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 {
                     // We can use `ScalarPair` only when it matches our
                     // already computed layout (including `#[repr(C)]`).
-                    abi = pair.abi;
+                    abi = pair.backend_repr;
                 }
             }
         }
@@ -942,12 +942,14 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
         // If we pick a "clever" (by-value) ABI, we might have to adjust the ABI of the
         // variants to ensure they are consistent. This is because a downcast is
         // semantically a NOP, and thus should not affect layout.
-        if matches!(abi, Abi::Scalar(..) | Abi::ScalarPair(..)) {
+        if matches!(abi, BackendRepr::Scalar(..) | BackendRepr::ScalarPair(..)) {
             for variant in &mut layout_variants {
                 // We only do this for variants with fields; the others are not accessed anyway.
                 // Also do not overwrite any already existing "clever" ABIs.
-                if variant.fields.count() > 0 && matches!(variant.abi, Abi::Aggregate { .. }) {
-                    variant.abi = abi;
+                if variant.fields.count() > 0
+                    && matches!(variant.backend_repr, BackendRepr::Memory { .. })
+                {
+                    variant.backend_repr = abi;
                     // Also need to bump up the size and alignment, so that the entire value fits
                     // in here.
                     variant.size = cmp::max(variant.size, size);
@@ -970,7 +972,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 memory_index: [0].into(),
             },
             largest_niche,
-            abi,
+            backend_repr: abi,
             align,
             size,
             max_repr_align,
@@ -1252,7 +1254,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
         }
         let mut layout_of_single_non_zst_field = None;
         let sized = unsized_field.is_none();
-        let mut abi = Abi::Aggregate { sized };
+        let mut abi = BackendRepr::Memory { sized };
 
         let optimize_abi = !repr.inhibit_newtype_abi_optimization();
 
@@ -1270,16 +1272,16 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                     // Field fills the struct and it has a scalar or scalar pair ABI.
                     if offsets[i].bytes() == 0 && align.abi == field.align.abi && size == field.size
                     {
-                        match field.abi {
+                        match field.backend_repr {
                             // For plain scalars, or vectors of them, we can't unpack
                             // newtypes for `#[repr(C)]`, as that affects C ABIs.
-                            Abi::Scalar(_) | Abi::Vector { .. } if optimize_abi => {
-                                abi = field.abi;
+                            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } if optimize_abi => {
+                                abi = field.backend_repr;
                             }
                             // But scalar pairs are Rust-specific and get
                             // treated as aggregates by C ABIs anyway.
-                            Abi::ScalarPair(..) => {
-                                abi = field.abi;
+                            BackendRepr::ScalarPair(..) => {
+                                abi = field.backend_repr;
                             }
                             _ => {}
                         }
@@ -1288,8 +1290,8 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
 
                 // Two non-ZST fields, and they're both scalars.
                 (Some((i, a)), Some((j, b)), None) => {
-                    match (a.abi, b.abi) {
-                        (Abi::Scalar(a), Abi::Scalar(b)) => {
+                    match (a.backend_repr, b.backend_repr) {
+                        (BackendRepr::Scalar(a), BackendRepr::Scalar(b)) => {
                             // Order by the memory placement, not source order.
                             let ((i, a), (j, b)) = if offsets[i] < offsets[j] {
                                 ((i, a), (j, b))
@@ -1315,7 +1317,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                             {
                                 // We can use `ScalarPair` only when it matches our
                                 // already computed layout (including `#[repr(C)]`).
-                                abi = pair.abi;
+                                abi = pair.backend_repr;
                             }
                         }
                         _ => {}
@@ -1325,8 +1327,8 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
                 _ => {}
             }
         }
-        if fields.iter().any(|f| f.abi.is_uninhabited()) {
-            abi = Abi::Uninhabited;
+        if fields.iter().any(|f| f.is_uninhabited()) {
+            abi = BackendRepr::Uninhabited;
         }
 
         let unadjusted_abi_align = if repr.transparent() {
@@ -1344,7 +1346,7 @@ impl<Cx: HasDataLayout> LayoutCalculator<Cx> {
         Ok(LayoutData {
             variants: Variants::Single { index: VariantIdx::new(0) },
             fields: FieldsShape::Arbitrary { offsets, memory_index },
-            abi,
+            backend_repr: abi,
             largest_niche,
             align,
             size,
diff --git a/compiler/rustc_abi/src/layout/ty.rs b/compiler/rustc_abi/src/layout/ty.rs
index e029e1426b218..062447ea03f08 100644
--- a/compiler/rustc_abi/src/layout/ty.rs
+++ b/compiler/rustc_abi/src/layout/ty.rs
@@ -83,8 +83,8 @@ impl<'a> Layout<'a> {
         &self.0.0.variants
     }
 
-    pub fn abi(self) -> Abi {
-        self.0.0.abi
+    pub fn backend_repr(self) -> BackendRepr {
+        self.0.0.backend_repr
     }
 
     pub fn largest_niche(self) -> Option<Niche> {
@@ -114,7 +114,7 @@ impl<'a> Layout<'a> {
     pub fn is_pointer_like(self, data_layout: &TargetDataLayout) -> bool {
         self.size() == data_layout.pointer_size
             && self.align().abi == data_layout.pointer_align.abi
-            && matches!(self.abi(), Abi::Scalar(Scalar::Initialized { .. }))
+            && matches!(self.backend_repr(), BackendRepr::Scalar(Scalar::Initialized { .. }))
     }
 }
 
@@ -196,9 +196,9 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
         Ty: TyAbiInterface<'a, C>,
         C: HasDataLayout,
     {
-        match self.abi {
-            Abi::Scalar(scalar) => matches!(scalar.primitive(), Float(F32 | F64)),
-            Abi::Aggregate { .. } => {
+        match self.backend_repr {
+            BackendRepr::Scalar(scalar) => matches!(scalar.primitive(), Float(F32 | F64)),
+            BackendRepr::Memory { .. } => {
                 if self.fields.count() == 1 && self.fields.offset(0).bytes() == 0 {
                     self.field(cx, 0).is_single_fp_element(cx)
                 } else {
diff --git a/compiler/rustc_abi/src/lib.rs b/compiler/rustc_abi/src/lib.rs
index 41922aee64877..fac1122c4dfc7 100644
--- a/compiler/rustc_abi/src/lib.rs
+++ b/compiler/rustc_abi/src/lib.rs
@@ -1344,11 +1344,19 @@ impl AddressSpace {
     pub const DATA: Self = AddressSpace(0);
 }
 
-/// Describes how values of the type are passed by target ABIs,
-/// in terms of categories of C types there are ABI rules for.
+/// The way we represent values to the backend
+///
+/// Previously this was conflated with the "ABI" a type is given, as in the platform-specific ABI.
+/// In reality, this implies little about that, but is mostly used to describe the syntactic form
+/// emitted for the backend, as most backends handle SSA values and blobs of memory differently.
+/// The psABI may need consideration in doing so, but this enum does not constitute a promise for
+/// how the value will be lowered to the calling convention, in itself.
+///
+/// Generally, a codegen backend will prefer to handle smaller values as a scalar or short vector,
+/// and larger values will usually prefer to be represented as memory.
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
 #[cfg_attr(feature = "nightly", derive(HashStable_Generic))]
-pub enum Abi {
+pub enum BackendRepr {
     Uninhabited,
     Scalar(Scalar),
     ScalarPair(Scalar, Scalar),
@@ -1356,19 +1364,23 @@ pub enum Abi {
         element: Scalar,
         count: u64,
     },
-    Aggregate {
+    // FIXME: I sometimes use memory, sometimes use an IR aggregate!
+    Memory {
         /// If true, the size is exact, otherwise it's only a lower bound.
         sized: bool,
     },
 }
 
-impl Abi {
+impl BackendRepr {
     /// Returns `true` if the layout corresponds to an unsized type.
     #[inline]
     pub fn is_unsized(&self) -> bool {
         match *self {
-            Abi::Uninhabited | Abi::Scalar(_) | Abi::ScalarPair(..) | Abi::Vector { .. } => false,
-            Abi::Aggregate { sized } => !sized,
+            BackendRepr::Uninhabited
+            | BackendRepr::Scalar(_)
+            | BackendRepr::ScalarPair(..)
+            | BackendRepr::Vector { .. } => false,
+            BackendRepr::Memory { sized } => !sized,
         }
     }
 
@@ -1381,7 +1393,7 @@ impl Abi {
     #[inline]
     pub fn is_signed(&self) -> bool {
         match self {
-            Abi::Scalar(scal) => match scal.primitive() {
+            BackendRepr::Scalar(scal) => match scal.primitive() {
                 Primitive::Int(_, signed) => signed,
                 _ => false,
             },
@@ -1392,61 +1404,67 @@ impl Abi {
     /// Returns `true` if this is an uninhabited type
     #[inline]
     pub fn is_uninhabited(&self) -> bool {
-        matches!(*self, Abi::Uninhabited)
+        matches!(*self, BackendRepr::Uninhabited)
     }
 
     /// Returns `true` if this is a scalar type
     #[inline]
     pub fn is_scalar(&self) -> bool {
-        matches!(*self, Abi::Scalar(_))
+        matches!(*self, BackendRepr::Scalar(_))
     }
 
     /// Returns `true` if this is a bool
     #[inline]
     pub fn is_bool(&self) -> bool {
-        matches!(*self, Abi::Scalar(s) if s.is_bool())
+        matches!(*self, BackendRepr::Scalar(s) if s.is_bool())
     }
 
     /// Returns the fixed alignment of this ABI, if any is mandated.
     pub fn inherent_align<C: HasDataLayout>(&self, cx: &C) -> Option<AbiAndPrefAlign> {
         Some(match *self {
-            Abi::Scalar(s) => s.align(cx),
-            Abi::ScalarPair(s1, s2) => s1.align(cx).max(s2.align(cx)),
-            Abi::Vector { element, count } => {
+            BackendRepr::Scalar(s) => s.align(cx),
+            BackendRepr::ScalarPair(s1, s2) => s1.align(cx).max(s2.align(cx)),
+            BackendRepr::Vector { element, count } => {
                 cx.data_layout().vector_align(element.size(cx) * count)
             }
-            Abi::Uninhabited | Abi::Aggregate { .. } => return None,
+            BackendRepr::Uninhabited | BackendRepr::Memory { .. } => return None,
         })
     }
 
     /// Returns the fixed size of this ABI, if any is mandated.
     pub fn inherent_size<C: HasDataLayout>(&self, cx: &C) -> Option<Size> {
         Some(match *self {
-            Abi::Scalar(s) => {
+            BackendRepr::Scalar(s) => {
                 // No padding in scalars.
                 s.size(cx)
             }
-            Abi::ScalarPair(s1, s2) => {
+            BackendRepr::ScalarPair(s1, s2) => {
                 // May have some padding between the pair.
                 let field2_offset = s1.size(cx).align_to(s2.align(cx).abi);
                 (field2_offset + s2.size(cx)).align_to(self.inherent_align(cx)?.abi)
             }
-            Abi::Vector { element, count } => {
+            BackendRepr::Vector { element, count } => {
                 // No padding in vectors, except possibly for trailing padding
                 // to make the size a multiple of align (e.g. for vectors of size 3).
                 (element.size(cx) * count).align_to(self.inherent_align(cx)?.abi)
             }
-            Abi::Uninhabited | Abi::Aggregate { .. } => return None,
+            BackendRepr::Uninhabited | BackendRepr::Memory { .. } => return None,
         })
     }
 
     /// Discard validity range information and allow undef.
     pub fn to_union(&self) -> Self {
         match *self {
-            Abi::Scalar(s) => Abi::Scalar(s.to_union()),
-            Abi::ScalarPair(s1, s2) => Abi::ScalarPair(s1.to_union(), s2.to_union()),
-            Abi::Vector { element, count } => Abi::Vector { element: element.to_union(), count },
-            Abi::Uninhabited | Abi::Aggregate { .. } => Abi::Aggregate { sized: true },
+            BackendRepr::Scalar(s) => BackendRepr::Scalar(s.to_union()),
+            BackendRepr::ScalarPair(s1, s2) => {
+                BackendRepr::ScalarPair(s1.to_union(), s2.to_union())
+            }
+            BackendRepr::Vector { element, count } => {
+                BackendRepr::Vector { element: element.to_union(), count }
+            }
+            BackendRepr::Uninhabited | BackendRepr::Memory { .. } => {
+                BackendRepr::Memory { sized: true }
+            }
         }
     }
 
@@ -1454,12 +1472,12 @@ impl Abi {
         match (self, other) {
             // Scalar, Vector, ScalarPair have `Scalar` in them where we ignore validity ranges.
             // We do *not* ignore the sign since it matters for some ABIs (e.g. s390x).
-            (Abi::Scalar(l), Abi::Scalar(r)) => l.primitive() == r.primitive(),
+            (BackendRepr::Scalar(l), BackendRepr::Scalar(r)) => l.primitive() == r.primitive(),
             (
-                Abi::Vector { element: element_l, count: count_l },
-                Abi::Vector { element: element_r, count: count_r },
+                BackendRepr::Vector { element: element_l, count: count_l },
+                BackendRepr::Vector { element: element_r, count: count_r },
             ) => element_l.primitive() == element_r.primitive() && count_l == count_r,
-            (Abi::ScalarPair(l1, l2), Abi::ScalarPair(r1, r2)) => {
+            (BackendRepr::ScalarPair(l1, l2), BackendRepr::ScalarPair(r1, r2)) => {
                 l1.primitive() == r1.primitive() && l2.primitive() == r2.primitive()
             }
             // Everything else must be strictly identical.
@@ -1616,14 +1634,14 @@ pub struct LayoutData<FieldIdx: Idx, VariantIdx: Idx> {
     /// must be taken into account.
     pub variants: Variants<FieldIdx, VariantIdx>,
 
-    /// The `abi` defines how this data is passed between functions, and it defines
-    /// value restrictions via `valid_range`.
+    /// The `backend_repr` defines how this data will be represented to the codegen backend,
+    /// and encodes value restrictions via `valid_range`.
     ///
     /// Note that this is entirely orthogonal to the recursive structure defined by
     /// `variants` and `fields`; for example, `ManuallyDrop<Result<isize, isize>>` has
-    /// `Abi::ScalarPair`! So, even with non-`Aggregate` `abi`, `fields` and `variants`
+    /// `IrForm::ScalarPair`! So, even with non-`Memory` `backend_repr`, `fields` and `variants`
     /// have to be taken into account to find all fields of this layout.
-    pub abi: Abi,
+    pub backend_repr: BackendRepr,
 
     /// The leaf scalar with the largest number of invalid values
     /// (i.e. outside of its `valid_range`), if it exists.
@@ -1646,15 +1664,15 @@ pub struct LayoutData<FieldIdx: Idx, VariantIdx: Idx> {
 impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
     /// Returns `true` if this is an aggregate type (including a ScalarPair!)
     pub fn is_aggregate(&self) -> bool {
-        match self.abi {
-            Abi::Uninhabited | Abi::Scalar(_) | Abi::Vector { .. } => false,
-            Abi::ScalarPair(..) | Abi::Aggregate { .. } => true,
+        match self.backend_repr {
+            BackendRepr::Uninhabited | BackendRepr::Scalar(_) | BackendRepr::Vector { .. } => false,
+            BackendRepr::ScalarPair(..) | BackendRepr::Memory { .. } => true,
         }
     }
 
     /// Returns `true` if this is an uninhabited type
     pub fn is_uninhabited(&self) -> bool {
-        self.abi.is_uninhabited()
+        self.backend_repr.is_uninhabited()
     }
 
     pub fn scalar<C: HasDataLayout>(cx: &C, scalar: Scalar) -> Self {
@@ -1664,7 +1682,7 @@ impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
         LayoutData {
             variants: Variants::Single { index: VariantIdx::new(0) },
             fields: FieldsShape::Primitive,
-            abi: Abi::Scalar(scalar),
+            backend_repr: BackendRepr::Scalar(scalar),
             largest_niche,
             size,
             align,
@@ -1686,7 +1704,7 @@ where
         let LayoutData {
             size,
             align,
-            abi,
+            backend_repr,
             fields,
             largest_niche,
             variants,
@@ -1696,7 +1714,7 @@ where
         f.debug_struct("Layout")
             .field("size", size)
             .field("align", align)
-            .field("abi", abi)
+            .field("abi", backend_repr)
             .field("fields", fields)
             .field("largest_niche", largest_niche)
             .field("variants", variants)
@@ -1732,12 +1750,12 @@ impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
     /// Returns `true` if the layout corresponds to an unsized type.
     #[inline]
     pub fn is_unsized(&self) -> bool {
-        self.abi.is_unsized()
+        self.backend_repr.is_unsized()
     }
 
     #[inline]
     pub fn is_sized(&self) -> bool {
-        self.abi.is_sized()
+        self.backend_repr.is_sized()
     }
 
     /// Returns `true` if the type is sized and a 1-ZST (meaning it has size 0 and alignment 1).
@@ -1750,10 +1768,12 @@ impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
     /// Note that this does *not* imply that the type is irrelevant for layout! It can still have
     /// non-trivial alignment constraints. You probably want to use `is_1zst` instead.
     pub fn is_zst(&self) -> bool {
-        match self.abi {
-            Abi::Scalar(_) | Abi::ScalarPair(..) | Abi::Vector { .. } => false,
-            Abi::Uninhabited => self.size.bytes() == 0,
-            Abi::Aggregate { sized } => sized && self.size.bytes() == 0,
+        match self.backend_repr {
+            BackendRepr::Scalar(_) | BackendRepr::ScalarPair(..) | BackendRepr::Vector { .. } => {
+                false
+            }
+            BackendRepr::Uninhabited => self.size.bytes() == 0,
+            BackendRepr::Memory { sized } => sized && self.size.bytes() == 0,
         }
     }
 
@@ -1768,8 +1788,8 @@ impl<FieldIdx: Idx, VariantIdx: Idx> LayoutData<FieldIdx, VariantIdx> {
         // 2nd point is quite hard to check though.
         self.size == other.size
             && self.is_sized() == other.is_sized()
-            && self.abi.eq_up_to_validity(&other.abi)
-            && self.abi.is_bool() == other.abi.is_bool()
+            && self.backend_repr.eq_up_to_validity(&other.backend_repr)
+            && self.backend_repr.is_bool() == other.backend_repr.is_bool()
             && self.align.abi == other.align.abi
             && self.max_repr_align == other.max_repr_align
             && self.unadjusted_abi_align == other.unadjusted_abi_align
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index 698fdafc93616..efcee2899c6f9 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -34,7 +34,7 @@ use rustc_infer::infer::{
 use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::*;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::{self, ParamEnv, RegionVid, TyCtxt};
+use rustc_middle::ty::{self, ParamEnv, RegionVid, TyCtxt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_mir_dataflow::Analysis;
 use rustc_mir_dataflow::impls::{
@@ -193,9 +193,7 @@ fn do_mir_borrowck<'tcx>(
         .map(|(idx, body)| (idx, MoveData::gather_moves(body, tcx, |_| true)));
 
     let mut flow_inits = MaybeInitializedPlaces::new(tcx, body, &move_data)
-        .into_engine(tcx, body)
-        .pass_name("borrowck")
-        .iterate_to_fixpoint()
+        .iterate_to_fixpoint(tcx, body, Some("borrowck"))
         .into_results_cursor(body);
 
     let locals_are_invalidated_at_exit = tcx.hir().body_owner_kind(def).is_fn_or_closure();
@@ -243,18 +241,21 @@ fn do_mir_borrowck<'tcx>(
     // usage significantly on some benchmarks.
     drop(flow_inits);
 
-    let flow_borrows = Borrows::new(tcx, body, &regioncx, &borrow_set)
-        .into_engine(tcx, body)
-        .pass_name("borrowck")
-        .iterate_to_fixpoint();
-    let flow_uninits = MaybeUninitializedPlaces::new(tcx, body, &move_data)
-        .into_engine(tcx, body)
-        .pass_name("borrowck")
-        .iterate_to_fixpoint();
-    let flow_ever_inits = EverInitializedPlaces::new(body, &move_data)
-        .into_engine(tcx, body)
-        .pass_name("borrowck")
-        .iterate_to_fixpoint();
+    let flow_borrows = Borrows::new(tcx, body, &regioncx, &borrow_set).iterate_to_fixpoint(
+        tcx,
+        body,
+        Some("borrowck"),
+    );
+    let flow_uninits = MaybeUninitializedPlaces::new(tcx, body, &move_data).iterate_to_fixpoint(
+        tcx,
+        body,
+        Some("borrowck"),
+    );
+    let flow_ever_inits = EverInitializedPlaces::new(body, &move_data).iterate_to_fixpoint(
+        tcx,
+        body,
+        Some("borrowck"),
+    );
 
     let movable_coroutine =
         // The first argument is the coroutine type passed by value
@@ -440,7 +441,7 @@ pub struct BorrowckInferCtxt<'tcx> {
 
 impl<'tcx> BorrowckInferCtxt<'tcx> {
     pub(crate) fn new(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> Self {
-        let infcx = tcx.infer_ctxt().with_opaque_type_inference(def_id).build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::analysis_in_body(tcx, def_id));
         BorrowckInferCtxt { infcx, reg_var_to_origin: RefCell::new(Default::default()) }
     }
 
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
index abce98265b3cb..741dac9e7639d 100644
--- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
+++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
@@ -9,6 +9,7 @@ use rustc_macros::extension;
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
     self, GenericArgKind, GenericArgs, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable,
+    TypingMode,
 };
 use rustc_span::Span;
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
@@ -340,14 +341,13 @@ fn check_opaque_type_well_formed<'tcx>(
         parent_def_id = tcx.local_parent(parent_def_id);
     }
 
-    // FIXME(-Znext-solver): We probably should use `&[]` instead of
-    // and prepopulate this `InferCtxt` with known opaque values, rather than
-    // allowing opaque types to be defined and checking them after the fact.
+    // FIXME(#132279): This should eventually use the already defined hidden types
+    // instead. Alternatively we'll entirely remove this function given we also check
+    // the opaque in `check_opaque_meets_bounds` later.
     let infcx = tcx
         .infer_ctxt()
         .with_next_trait_solver(next_trait_solver)
-        .with_opaque_type_inference(parent_def_id)
-        .build();
+        .build(TypingMode::analysis_in_body(tcx, parent_def_id));
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
     let identity_args = GenericArgs::identity_for_item(tcx, def_id);
 
@@ -517,7 +517,9 @@ impl<'tcx> LazyOpaqueTyEnv<'tcx> {
             },
         );
 
-        let infcx = tcx.infer_ctxt().build();
+        // FIXME(#132279): It feels wrong to use `non_body_analysis` here given that we're
+        // in a body here.
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let ocx = ObligationCtxt::new(&infcx);
 
         let wf_tys = ocx.assumed_wf_types(param_env, parent).unwrap_or_else(|_| {
diff --git a/compiler/rustc_codegen_cranelift/src/abi/mod.rs b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
index 892ec3e95855e..089b09d06aef2 100644
--- a/compiler/rustc_codegen_cranelift/src/abi/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
@@ -193,7 +193,7 @@ fn make_local_place<'tcx>(
         );
     }
     let place = if is_ssa {
-        if let rustc_target::abi::Abi::ScalarPair(_, _) = layout.abi {
+        if let BackendRepr::ScalarPair(_, _) = layout.backend_repr {
             CPlace::new_var_pair(fx, local, layout)
         } else {
             CPlace::new_var(fx, local, layout)
diff --git a/compiler/rustc_codegen_cranelift/src/abi/pass_mode.rs b/compiler/rustc_codegen_cranelift/src/abi/pass_mode.rs
index 38c322b5e0450..ad0a13dc7e574 100644
--- a/compiler/rustc_codegen_cranelift/src/abi/pass_mode.rs
+++ b/compiler/rustc_codegen_cranelift/src/abi/pass_mode.rs
@@ -78,19 +78,19 @@ impl<'tcx> ArgAbiExt<'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
     fn get_abi_param(&self, tcx: TyCtxt<'tcx>) -> SmallVec<[AbiParam; 2]> {
         match self.mode {
             PassMode::Ignore => smallvec![],
-            PassMode::Direct(attrs) => match self.layout.abi {
-                Abi::Scalar(scalar) => smallvec![apply_arg_attrs_to_abi_param(
+            PassMode::Direct(attrs) => match self.layout.backend_repr {
+                BackendRepr::Scalar(scalar) => smallvec![apply_arg_attrs_to_abi_param(
                     AbiParam::new(scalar_to_clif_type(tcx, scalar)),
                     attrs
                 )],
-                Abi::Vector { .. } => {
+                BackendRepr::Vector { .. } => {
                     let vector_ty = crate::intrinsics::clif_vector_type(tcx, self.layout);
                     smallvec![AbiParam::new(vector_ty)]
                 }
-                _ => unreachable!("{:?}", self.layout.abi),
+                _ => unreachable!("{:?}", self.layout.backend_repr),
             },
-            PassMode::Pair(attrs_a, attrs_b) => match self.layout.abi {
-                Abi::ScalarPair(a, b) => {
+            PassMode::Pair(attrs_a, attrs_b) => match self.layout.backend_repr {
+                BackendRepr::ScalarPair(a, b) => {
                     let a = scalar_to_clif_type(tcx, a);
                     let b = scalar_to_clif_type(tcx, b);
                     smallvec![
@@ -98,7 +98,7 @@ impl<'tcx> ArgAbiExt<'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
                         apply_arg_attrs_to_abi_param(AbiParam::new(b), attrs_b),
                     ]
                 }
-                _ => unreachable!("{:?}", self.layout.abi),
+                _ => unreachable!("{:?}", self.layout.backend_repr),
             },
             PassMode::Cast { ref cast, pad_i32 } => {
                 assert!(!pad_i32, "padding support not yet implemented");
@@ -130,23 +130,23 @@ impl<'tcx> ArgAbiExt<'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
     fn get_abi_return(&self, tcx: TyCtxt<'tcx>) -> (Option<AbiParam>, Vec<AbiParam>) {
         match self.mode {
             PassMode::Ignore => (None, vec![]),
-            PassMode::Direct(_) => match self.layout.abi {
-                Abi::Scalar(scalar) => {
+            PassMode::Direct(_) => match self.layout.backend_repr {
+                BackendRepr::Scalar(scalar) => {
                     (None, vec![AbiParam::new(scalar_to_clif_type(tcx, scalar))])
                 }
-                Abi::Vector { .. } => {
+                BackendRepr::Vector { .. } => {
                     let vector_ty = crate::intrinsics::clif_vector_type(tcx, self.layout);
                     (None, vec![AbiParam::new(vector_ty)])
                 }
-                _ => unreachable!("{:?}", self.layout.abi),
+                _ => unreachable!("{:?}", self.layout.backend_repr),
             },
-            PassMode::Pair(_, _) => match self.layout.abi {
-                Abi::ScalarPair(a, b) => {
+            PassMode::Pair(_, _) => match self.layout.backend_repr {
+                BackendRepr::ScalarPair(a, b) => {
                     let a = scalar_to_clif_type(tcx, a);
                     let b = scalar_to_clif_type(tcx, b);
                     (None, vec![AbiParam::new(a), AbiParam::new(b)])
                 }
-                _ => unreachable!("{:?}", self.layout.abi),
+                _ => unreachable!("{:?}", self.layout.backend_repr),
             },
             PassMode::Cast { ref cast, .. } => {
                 (None, cast_target_to_abi_params(cast).into_iter().collect())
diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs
index a681e6d9f3cd1..99e39971b7479 100644
--- a/compiler/rustc_codegen_cranelift/src/base.rs
+++ b/compiler/rustc_codegen_cranelift/src/base.rs
@@ -290,7 +290,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
     let arg_uninhabited = fx
         .mir
         .args_iter()
-        .any(|arg| fx.layout_of(fx.monomorphize(fx.mir.local_decls[arg].ty)).abi.is_uninhabited());
+        .any(|arg| fx.layout_of(fx.monomorphize(fx.mir.local_decls[arg].ty)).is_uninhabited());
     if arg_uninhabited {
         fx.bcx.append_block_params_for_function_params(fx.block_map[START_BLOCK]);
         fx.bcx.switch_to_block(fx.block_map[START_BLOCK]);
@@ -644,9 +644,9 @@ fn codegen_stmt<'tcx>(
                                 _ => unreachable!("un op Neg for {:?}", layout.ty),
                             }
                         }
-                        UnOp::PtrMetadata => match layout.abi {
-                            Abi::Scalar(_) => CValue::zst(dest_layout),
-                            Abi::ScalarPair(_, _) => {
+                        UnOp::PtrMetadata => match layout.backend_repr {
+                            BackendRepr::Scalar(_) => CValue::zst(dest_layout),
+                            BackendRepr::ScalarPair(_, _) => {
                                 CValue::by_val(operand.load_scalar_pair(fx).1, dest_layout)
                             }
                             _ => bug!("Unexpected `PtrToMetadata` operand: {operand:?}"),
diff --git a/compiler/rustc_codegen_cranelift/src/discriminant.rs b/compiler/rustc_codegen_cranelift/src/discriminant.rs
index d462dcd63a925..45794a4266589 100644
--- a/compiler/rustc_codegen_cranelift/src/discriminant.rs
+++ b/compiler/rustc_codegen_cranelift/src/discriminant.rs
@@ -14,7 +14,7 @@ pub(crate) fn codegen_set_discriminant<'tcx>(
     variant_index: VariantIdx,
 ) {
     let layout = place.layout();
-    if layout.for_variant(fx, variant_index).abi.is_uninhabited() {
+    if layout.for_variant(fx, variant_index).is_uninhabited() {
         return;
     }
     match layout.variants {
@@ -80,7 +80,7 @@ pub(crate) fn codegen_get_discriminant<'tcx>(
 ) {
     let layout = value.layout();
 
-    if layout.abi.is_uninhabited() {
+    if layout.is_uninhabited() {
         return;
     }
 
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
index 35f0ccff3f99e..aae6794891d76 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
@@ -51,8 +51,8 @@ fn report_atomic_type_validation_error<'tcx>(
 }
 
 pub(crate) fn clif_vector_type<'tcx>(tcx: TyCtxt<'tcx>, layout: TyAndLayout<'tcx>) -> Type {
-    let (element, count) = match layout.abi {
-        Abi::Vector { element, count } => (element, count),
+    let (element, count) = match layout.backend_repr {
+        BackendRepr::Vector { element, count } => (element, count),
         _ => unreachable!(),
     };
 
@@ -505,7 +505,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
             let layout = fx.layout_of(generic_args.type_at(0));
             // Note: Can't use is_unsized here as truly unsized types need to take the fixed size
             // branch
-            let meta = if let Abi::ScalarPair(_, _) = ptr.layout().abi {
+            let meta = if let BackendRepr::ScalarPair(_, _) = ptr.layout().backend_repr {
                 Some(ptr.load_scalar_pair(fx).1)
             } else {
                 None
@@ -519,7 +519,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
             let layout = fx.layout_of(generic_args.type_at(0));
             // Note: Can't use is_unsized here as truly unsized types need to take the fixed size
             // branch
-            let meta = if let Abi::ScalarPair(_, _) = ptr.layout().abi {
+            let meta = if let BackendRepr::ScalarPair(_, _) = ptr.layout().backend_repr {
                 Some(ptr.load_scalar_pair(fx).1)
             } else {
                 None
@@ -693,7 +693,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
                     let layout = fx.layout_of(ty);
                     let msg_str = with_no_visible_paths!({
                         with_no_trimmed_paths!({
-                            if layout.abi.is_uninhabited() {
+                            if layout.is_uninhabited() {
                                 // Use this error even for the other intrinsics as it is more precise.
                                 format!("attempted to instantiate uninhabited type `{}`", ty)
                             } else if intrinsic == sym::assert_zero_valid {
diff --git a/compiler/rustc_codegen_cranelift/src/lib.rs b/compiler/rustc_codegen_cranelift/src/lib.rs
index b6f9ce8fc2988..602b1b9820023 100644
--- a/compiler/rustc_codegen_cranelift/src/lib.rs
+++ b/compiler/rustc_codegen_cranelift/src/lib.rs
@@ -92,6 +92,7 @@ mod prelude {
         StackSlotData, StackSlotKind, TrapCode, Type, Value, types,
     };
     pub(crate) use cranelift_module::{self, DataDescription, FuncId, Linkage, Module};
+    pub(crate) use rustc_abi::{BackendRepr, FIRST_VARIANT, FieldIdx, Scalar, Size, VariantIdx};
     pub(crate) use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
     pub(crate) use rustc_hir::def_id::{DefId, LOCAL_CRATE};
     pub(crate) use rustc_index::Idx;
@@ -101,7 +102,6 @@ mod prelude {
         self, FloatTy, Instance, InstanceKind, IntTy, ParamEnv, Ty, TyCtxt, UintTy,
     };
     pub(crate) use rustc_span::Span;
-    pub(crate) use rustc_target::abi::{Abi, FIRST_VARIANT, FieldIdx, Scalar, Size, VariantIdx};
 
     pub(crate) use crate::abi::*;
     pub(crate) use crate::base::{codegen_operand, codegen_place};
diff --git a/compiler/rustc_codegen_cranelift/src/value_and_place.rs b/compiler/rustc_codegen_cranelift/src/value_and_place.rs
index fd77502224e4c..900d7e69714ea 100644
--- a/compiler/rustc_codegen_cranelift/src/value_and_place.rs
+++ b/compiler/rustc_codegen_cranelift/src/value_and_place.rs
@@ -131,8 +131,8 @@ impl<'tcx> CValue<'tcx> {
 
         match self.0 {
             CValueInner::ByRef(ptr, None) => {
-                let (a_scalar, b_scalar) = match self.1.abi {
-                    Abi::ScalarPair(a, b) => (a, b),
+                let (a_scalar, b_scalar) = match self.1.backend_repr {
+                    BackendRepr::ScalarPair(a, b) => (a, b),
                     _ => unreachable!("dyn_star_force_data_on_stack({:?})", self),
                 };
                 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
@@ -164,15 +164,15 @@ impl<'tcx> CValue<'tcx> {
         }
     }
 
-    /// Load a value with layout.abi of scalar
+    /// Load a value with layout.backend_repr of scalar
     #[track_caller]
     pub(crate) fn load_scalar(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> Value {
         let layout = self.1;
         match self.0 {
             CValueInner::ByRef(ptr, None) => {
-                let clif_ty = match layout.abi {
-                    Abi::Scalar(scalar) => scalar_to_clif_type(fx.tcx, scalar),
-                    Abi::Vector { element, count } => scalar_to_clif_type(fx.tcx, element)
+                let clif_ty = match layout.backend_repr {
+                    BackendRepr::Scalar(scalar) => scalar_to_clif_type(fx.tcx, scalar),
+                    BackendRepr::Vector { element, count } => scalar_to_clif_type(fx.tcx, element)
                         .by(u32::try_from(count).unwrap())
                         .unwrap(),
                     _ => unreachable!("{:?}", layout.ty),
@@ -187,14 +187,14 @@ impl<'tcx> CValue<'tcx> {
         }
     }
 
-    /// Load a value pair with layout.abi of scalar pair
+    /// Load a value pair with layout.backend_repr of scalar pair
     #[track_caller]
     pub(crate) fn load_scalar_pair(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> (Value, Value) {
         let layout = self.1;
         match self.0 {
             CValueInner::ByRef(ptr, None) => {
-                let (a_scalar, b_scalar) = match layout.abi {
-                    Abi::ScalarPair(a, b) => (a, b),
+                let (a_scalar, b_scalar) = match layout.backend_repr {
+                    BackendRepr::ScalarPair(a, b) => (a, b),
                     _ => unreachable!("load_scalar_pair({:?})", self),
                 };
                 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
@@ -222,8 +222,8 @@ impl<'tcx> CValue<'tcx> {
         let layout = self.1;
         match self.0 {
             CValueInner::ByVal(_) => unreachable!(),
-            CValueInner::ByValPair(val1, val2) => match layout.abi {
-                Abi::ScalarPair(_, _) => {
+            CValueInner::ByValPair(val1, val2) => match layout.backend_repr {
+                BackendRepr::ScalarPair(_, _) => {
                     let val = match field.as_u32() {
                         0 => val1,
                         1 => val2,
@@ -232,7 +232,7 @@ impl<'tcx> CValue<'tcx> {
                     let field_layout = layout.field(&*fx, usize::from(field));
                     CValue::by_val(val, field_layout)
                 }
-                _ => unreachable!("value_field for ByValPair with abi {:?}", layout.abi),
+                _ => unreachable!("value_field for ByValPair with abi {:?}", layout.backend_repr),
             },
             CValueInner::ByRef(ptr, None) => {
                 let (field_ptr, field_layout) = codegen_field(fx, ptr, None, layout, field);
@@ -360,7 +360,7 @@ impl<'tcx> CValue<'tcx> {
     pub(crate) fn cast_pointer_to(self, layout: TyAndLayout<'tcx>) -> Self {
         assert!(matches!(self.layout().ty.kind(), ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..)));
         assert!(matches!(layout.ty.kind(), ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..)));
-        assert_eq!(self.layout().abi, layout.abi);
+        assert_eq!(self.layout().backend_repr, layout.backend_repr);
         CValue(self.0, layout)
     }
 }
@@ -609,8 +609,8 @@ impl<'tcx> CPlace<'tcx> {
         let dst_layout = self.layout();
         match self.inner {
             CPlaceInner::Var(_local, var) => {
-                let data = match from.1.abi {
-                    Abi::Scalar(_) => CValue(from.0, dst_layout).load_scalar(fx),
+                let data = match from.1.backend_repr {
+                    BackendRepr::Scalar(_) => CValue(from.0, dst_layout).load_scalar(fx),
                     _ => {
                         let (ptr, meta) = from.force_stack(fx);
                         assert!(meta.is_none());
@@ -621,8 +621,10 @@ impl<'tcx> CPlace<'tcx> {
                 transmute_scalar(fx, var, data, dst_ty);
             }
             CPlaceInner::VarPair(_local, var1, var2) => {
-                let (data1, data2) = match from.1.abi {
-                    Abi::ScalarPair(_, _) => CValue(from.0, dst_layout).load_scalar_pair(fx),
+                let (data1, data2) = match from.1.backend_repr {
+                    BackendRepr::ScalarPair(_, _) => {
+                        CValue(from.0, dst_layout).load_scalar_pair(fx)
+                    }
                     _ => {
                         let (ptr, meta) = from.force_stack(fx);
                         assert!(meta.is_none());
@@ -635,7 +637,9 @@ impl<'tcx> CPlace<'tcx> {
             }
             CPlaceInner::Addr(_, Some(_)) => bug!("Can't write value to unsized place {:?}", self),
             CPlaceInner::Addr(to_ptr, None) => {
-                if dst_layout.size == Size::ZERO || dst_layout.abi == Abi::Uninhabited {
+                if dst_layout.size == Size::ZERO
+                    || dst_layout.backend_repr == BackendRepr::Uninhabited
+                {
                     return;
                 }
 
@@ -646,23 +650,28 @@ impl<'tcx> CPlace<'tcx> {
                     CValueInner::ByVal(val) => {
                         to_ptr.store(fx, val, flags);
                     }
-                    CValueInner::ByValPair(val1, val2) => match from.layout().abi {
-                        Abi::ScalarPair(a_scalar, b_scalar) => {
+                    CValueInner::ByValPair(val1, val2) => match from.layout().backend_repr {
+                        BackendRepr::ScalarPair(a_scalar, b_scalar) => {
                             let b_offset =
                                 scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
                             to_ptr.store(fx, val1, flags);
                             to_ptr.offset(fx, b_offset).store(fx, val2, flags);
                         }
-                        _ => bug!("Non ScalarPair abi {:?} for ByValPair CValue", dst_layout.abi),
+                        _ => {
+                            bug!(
+                                "Non ScalarPair repr {:?} for ByValPair CValue",
+                                dst_layout.backend_repr
+                            )
+                        }
                     },
                     CValueInner::ByRef(from_ptr, None) => {
-                        match from.layout().abi {
-                            Abi::Scalar(_) => {
+                        match from.layout().backend_repr {
+                            BackendRepr::Scalar(_) => {
                                 let val = from.load_scalar(fx);
                                 to_ptr.store(fx, val, flags);
                                 return;
                             }
-                            Abi::ScalarPair(a_scalar, b_scalar) => {
+                            BackendRepr::ScalarPair(a_scalar, b_scalar) => {
                                 let b_offset =
                                     scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
                                 let (val1, val2) = from.load_scalar_pair(fx);
diff --git a/compiler/rustc_codegen_cranelift/src/vtable.rs b/compiler/rustc_codegen_cranelift/src/vtable.rs
index 14c607ccad7d7..82b6178be9dcd 100644
--- a/compiler/rustc_codegen_cranelift/src/vtable.rs
+++ b/compiler/rustc_codegen_cranelift/src/vtable.rs
@@ -47,7 +47,7 @@ pub(crate) fn get_ptr_and_method_ref<'tcx>(
     idx: usize,
 ) -> (Pointer, Value) {
     let (ptr, vtable) = 'block: {
-        if let Abi::Scalar(_) = arg.layout().abi {
+        if let BackendRepr::Scalar(_) = arg.layout().backend_repr {
             while !arg.layout().ty.is_unsafe_ptr() && !arg.layout().ty.is_ref() {
                 let (idx, _) = arg
                     .layout()
@@ -68,7 +68,7 @@ pub(crate) fn get_ptr_and_method_ref<'tcx>(
             }
         }
 
-        if let Abi::ScalarPair(_, _) = arg.layout().abi {
+        if let BackendRepr::ScalarPair(_, _) = arg.layout().backend_repr {
             let (ptr, vtable) = arg.load_scalar_pair(fx);
             (Pointer::new(ptr), vtable)
         } else {
diff --git a/compiler/rustc_codegen_gcc/src/builder.rs b/compiler/rustc_codegen_gcc/src/builder.rs
index 7c52cba096b40..e6ae7cf174d0e 100644
--- a/compiler/rustc_codegen_gcc/src/builder.rs
+++ b/compiler/rustc_codegen_gcc/src/builder.rs
@@ -1016,11 +1016,11 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
             OperandValue::Ref(place.val)
         } else if place.layout.is_gcc_immediate() {
             let load = self.load(place.layout.gcc_type(self), place.val.llval, place.val.align);
-            if let abi::Abi::Scalar(ref scalar) = place.layout.abi {
+            if let abi::BackendRepr::Scalar(ref scalar) = place.layout.backend_repr {
                 scalar_load_metadata(self, load, scalar);
             }
             OperandValue::Immediate(self.to_immediate(load, place.layout))
-        } else if let abi::Abi::ScalarPair(ref a, ref b) = place.layout.abi {
+        } else if let abi::BackendRepr::ScalarPair(ref a, ref b) = place.layout.backend_repr {
             let b_offset = a.size(self).align_to(b.align(self).abi);
 
             let mut load = |i, scalar: &abi::Scalar, align| {
diff --git a/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs b/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs
index 972d66321403d..b0298a35cb083 100644
--- a/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs
+++ b/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs
@@ -294,13 +294,13 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
             }
 
             sym::raw_eq => {
-                use rustc_target::abi::Abi::*;
+                use rustc_abi::BackendRepr::*;
                 let tp_ty = fn_args.type_at(0);
                 let layout = self.layout_of(tp_ty).layout;
-                let _use_integer_compare = match layout.abi() {
+                let _use_integer_compare = match layout.backend_repr() {
                     Scalar(_) | ScalarPair(_, _) => true,
                     Uninhabited | Vector { .. } => false,
-                    Aggregate { .. } => {
+                    Memory { .. } => {
                         // For rusty ABIs, small aggregates are actually passed
                         // as `RegKind::Integer` (see `FnAbi::adjust_for_abi`),
                         // so we re-use that same threshold here.
diff --git a/compiler/rustc_codegen_gcc/src/type_of.rs b/compiler/rustc_codegen_gcc/src/type_of.rs
index db874afe1ab9b..0efdf36da485e 100644
--- a/compiler/rustc_codegen_gcc/src/type_of.rs
+++ b/compiler/rustc_codegen_gcc/src/type_of.rs
@@ -3,7 +3,7 @@ use std::fmt::Write;
 use gccjit::{Struct, Type};
 use rustc_abi as abi;
 use rustc_abi::Primitive::*;
-use rustc_abi::{Abi, FieldsShape, Integer, PointeeInfo, Size, Variants};
+use rustc_abi::{BackendRepr, FieldsShape, Integer, PointeeInfo, Size, Variants};
 use rustc_codegen_ssa::traits::{
     BaseTypeCodegenMethods, DerivedTypeCodegenMethods, LayoutTypeCodegenMethods,
 };
@@ -60,9 +60,9 @@ fn uncached_gcc_type<'gcc, 'tcx>(
     layout: TyAndLayout<'tcx>,
     defer: &mut Option<(Struct<'gcc>, TyAndLayout<'tcx>)>,
 ) -> Type<'gcc> {
-    match layout.abi {
-        Abi::Scalar(_) => bug!("handled elsewhere"),
-        Abi::Vector { ref element, count } => {
+    match layout.backend_repr {
+        BackendRepr::Scalar(_) => bug!("handled elsewhere"),
+        BackendRepr::Vector { ref element, count } => {
             let element = layout.scalar_gcc_type_at(cx, element, Size::ZERO);
             let element =
                 // NOTE: gcc doesn't allow pointer types in vectors.
@@ -74,7 +74,7 @@ fn uncached_gcc_type<'gcc, 'tcx>(
                 };
             return cx.context.new_vector_type(element, count);
         }
-        Abi::ScalarPair(..) => {
+        BackendRepr::ScalarPair(..) => {
             return cx.type_struct(
                 &[
                     layout.scalar_pair_element_gcc_type(cx, 0),
@@ -83,7 +83,7 @@ fn uncached_gcc_type<'gcc, 'tcx>(
                 false,
             );
         }
-        Abi::Uninhabited | Abi::Aggregate { .. } => {}
+        BackendRepr::Uninhabited | BackendRepr::Memory { .. } => {}
     }
 
     let name = match *layout.ty.kind() {
@@ -176,16 +176,21 @@ pub trait LayoutGccExt<'tcx> {
 
 impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
     fn is_gcc_immediate(&self) -> bool {
-        match self.abi {
-            Abi::Scalar(_) | Abi::Vector { .. } => true,
-            Abi::ScalarPair(..) | Abi::Uninhabited | Abi::Aggregate { .. } => false,
+        match self.backend_repr {
+            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } => true,
+            BackendRepr::ScalarPair(..) | BackendRepr::Uninhabited | BackendRepr::Memory { .. } => {
+                false
+            }
         }
     }
 
     fn is_gcc_scalar_pair(&self) -> bool {
-        match self.abi {
-            Abi::ScalarPair(..) => true,
-            Abi::Uninhabited | Abi::Scalar(_) | Abi::Vector { .. } | Abi::Aggregate { .. } => false,
+        match self.backend_repr {
+            BackendRepr::ScalarPair(..) => true,
+            BackendRepr::Uninhabited
+            | BackendRepr::Scalar(_)
+            | BackendRepr::Vector { .. }
+            | BackendRepr::Memory { .. } => false,
         }
     }
 
@@ -205,7 +210,7 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
         // This must produce the same result for `repr(transparent)` wrappers as for the inner type!
         // In other words, this should generally not look at the type at all, but only at the
         // layout.
-        if let Abi::Scalar(ref scalar) = self.abi {
+        if let BackendRepr::Scalar(ref scalar) = self.backend_repr {
             // Use a different cache for scalars because pointers to DSTs
             // can be either wide or thin (data pointers of wide pointers).
             if let Some(&ty) = cx.scalar_types.borrow().get(&self.ty) {
@@ -261,7 +266,7 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
     }
 
     fn immediate_gcc_type<'gcc>(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc> {
-        if let Abi::Scalar(ref scalar) = self.abi {
+        if let BackendRepr::Scalar(ref scalar) = self.backend_repr {
             if scalar.is_bool() {
                 return cx.type_i1();
             }
@@ -299,8 +304,8 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
         // This must produce the same result for `repr(transparent)` wrappers as for the inner type!
         // In other words, this should generally not look at the type at all, but only at the
         // layout.
-        let (a, b) = match self.abi {
-            Abi::ScalarPair(ref a, ref b) => (a, b),
+        let (a, b) = match self.backend_repr {
+            BackendRepr::ScalarPair(ref a, ref b) => (a, b),
             _ => bug!("TyAndLayout::scalar_pair_element_llty({:?}): not applicable", self),
         };
         let scalar = [a, b][index];
diff --git a/compiler/rustc_codegen_llvm/src/abi.rs b/compiler/rustc_codegen_llvm/src/abi.rs
index 8a1ee48c43ca3..855ca01061190 100644
--- a/compiler/rustc_codegen_llvm/src/abi.rs
+++ b/compiler/rustc_codegen_llvm/src/abi.rs
@@ -458,7 +458,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
         match &self.ret.mode {
             PassMode::Direct(attrs) => {
                 attrs.apply_attrs_to_llfn(llvm::AttributePlace::ReturnValue, cx, llfn);
-                if let abi::Abi::Scalar(scalar) = self.ret.layout.abi {
+                if let abi::BackendRepr::Scalar(scalar) = self.ret.layout.backend_repr {
                     apply_range_attr(llvm::AttributePlace::ReturnValue, scalar);
                 }
             }
@@ -495,7 +495,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                 }
                 PassMode::Direct(attrs) => {
                     let i = apply(attrs);
-                    if let abi::Abi::Scalar(scalar) = arg.layout.abi {
+                    if let abi::BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
                         apply_range_attr(llvm::AttributePlace::Argument(i), scalar);
                     }
                 }
@@ -510,7 +510,9 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                 PassMode::Pair(a, b) => {
                     let i = apply(a);
                     let ii = apply(b);
-                    if let abi::Abi::ScalarPair(scalar_a, scalar_b) = arg.layout.abi {
+                    if let abi::BackendRepr::ScalarPair(scalar_a, scalar_b) =
+                        arg.layout.backend_repr
+                    {
                         apply_range_attr(llvm::AttributePlace::Argument(i), scalar_a);
                         apply_range_attr(llvm::AttributePlace::Argument(ii), scalar_b);
                     }
@@ -570,7 +572,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
         }
         if bx.cx.sess().opts.optimize != config::OptLevel::No
                 && llvm_util::get_version() < (19, 0, 0)
-                && let abi::Abi::Scalar(scalar) = self.ret.layout.abi
+                && let abi::BackendRepr::Scalar(scalar) = self.ret.layout.backend_repr
                 && matches!(scalar.primitive(), Int(..))
                 // If the value is a boolean, the range is 0..2 and that ultimately
                 // become 0..0 when the type becomes i1, which would be rejected
diff --git a/compiler/rustc_codegen_llvm/src/asm.rs b/compiler/rustc_codegen_llvm/src/asm.rs
index 3c30822a2e2f4..53758967552d4 100644
--- a/compiler/rustc_codegen_llvm/src/asm.rs
+++ b/compiler/rustc_codegen_llvm/src/asm.rs
@@ -880,8 +880,8 @@ fn llvm_fixup_input<'ll, 'tcx>(
 ) -> &'ll Value {
     use InlineAsmRegClass::*;
     let dl = &bx.tcx.data_layout;
-    match (reg, layout.abi) {
-        (AArch64(AArch64InlineAsmRegClass::vreg), Abi::Scalar(s)) => {
+    match (reg, layout.backend_repr) {
+        (AArch64(AArch64InlineAsmRegClass::vreg), BackendRepr::Scalar(s)) => {
             if let Primitive::Int(Integer::I8, _) = s.primitive() {
                 let vec_ty = bx.cx.type_vector(bx.cx.type_i8(), 8);
                 bx.insert_element(bx.const_undef(vec_ty), value, bx.const_i32(0))
@@ -889,7 +889,7 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 value
             }
         }
-        (AArch64(AArch64InlineAsmRegClass::vreg_low16), Abi::Scalar(s))
+        (AArch64(AArch64InlineAsmRegClass::vreg_low16), BackendRepr::Scalar(s))
             if s.primitive() != Primitive::Float(Float::F128) =>
         {
             let elem_ty = llvm_asm_scalar_type(bx.cx, s);
@@ -902,7 +902,7 @@ fn llvm_fixup_input<'ll, 'tcx>(
             }
             bx.insert_element(bx.const_undef(vec_ty), value, bx.const_i32(0))
         }
-        (AArch64(AArch64InlineAsmRegClass::vreg_low16), Abi::Vector { element, count })
+        (AArch64(AArch64InlineAsmRegClass::vreg_low16), BackendRepr::Vector { element, count })
             if layout.size.bytes() == 8 =>
         {
             let elem_ty = llvm_asm_scalar_type(bx.cx, element);
@@ -910,14 +910,14 @@ fn llvm_fixup_input<'ll, 'tcx>(
             let indices: Vec<_> = (0..count * 2).map(|x| bx.const_i32(x as i32)).collect();
             bx.shuffle_vector(value, bx.const_undef(vec_ty), bx.const_vector(&indices))
         }
-        (X86(X86InlineAsmRegClass::reg_abcd), Abi::Scalar(s))
+        (X86(X86InlineAsmRegClass::reg_abcd), BackendRepr::Scalar(s))
             if s.primitive() == Primitive::Float(Float::F64) =>
         {
             bx.bitcast(value, bx.cx.type_i64())
         }
         (
             X86(X86InlineAsmRegClass::xmm_reg | X86InlineAsmRegClass::zmm_reg),
-            Abi::Vector { .. },
+            BackendRepr::Vector { .. },
         ) if layout.size.bytes() == 64 => bx.bitcast(value, bx.cx.type_vector(bx.cx.type_f64(), 8)),
         (
             X86(
@@ -925,7 +925,7 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) if bx.sess().asm_arch == Some(InlineAsmArch::X86)
             && s.primitive() == Primitive::Float(Float::F128) =>
         {
@@ -937,7 +937,7 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) if s.primitive() == Primitive::Float(Float::F16) => {
             let value = bx.insert_element(
                 bx.const_undef(bx.type_vector(bx.type_f16(), 8)),
@@ -952,11 +952,14 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Vector { element, count: count @ (8 | 16) },
+            BackendRepr::Vector { element, count: count @ (8 | 16) },
         ) if element.primitive() == Primitive::Float(Float::F16) => {
             bx.bitcast(value, bx.type_vector(bx.type_i16(), count))
         }
-        (Arm(ArmInlineAsmRegClass::sreg | ArmInlineAsmRegClass::sreg_low16), Abi::Scalar(s)) => {
+        (
+            Arm(ArmInlineAsmRegClass::sreg | ArmInlineAsmRegClass::sreg_low16),
+            BackendRepr::Scalar(s),
+        ) => {
             if let Primitive::Int(Integer::I32, _) = s.primitive() {
                 bx.bitcast(value, bx.cx.type_f32())
             } else {
@@ -969,7 +972,7 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 | ArmInlineAsmRegClass::dreg_low8
                 | ArmInlineAsmRegClass::dreg_low16,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) => {
             if let Primitive::Int(Integer::I64, _) = s.primitive() {
                 bx.bitcast(value, bx.cx.type_f64())
@@ -986,11 +989,11 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 | ArmInlineAsmRegClass::qreg_low4
                 | ArmInlineAsmRegClass::qreg_low8,
             ),
-            Abi::Vector { element, count: count @ (4 | 8) },
+            BackendRepr::Vector { element, count: count @ (4 | 8) },
         ) if element.primitive() == Primitive::Float(Float::F16) => {
             bx.bitcast(value, bx.type_vector(bx.type_i16(), count))
         }
-        (Mips(MipsInlineAsmRegClass::reg), Abi::Scalar(s)) => {
+        (Mips(MipsInlineAsmRegClass::reg), BackendRepr::Scalar(s)) => {
             match s.primitive() {
                 // MIPS only supports register-length arithmetics.
                 Primitive::Int(Integer::I8 | Integer::I16, _) => bx.zext(value, bx.cx.type_i32()),
@@ -999,7 +1002,7 @@ fn llvm_fixup_input<'ll, 'tcx>(
                 _ => value,
             }
         }
-        (RiscV(RiscVInlineAsmRegClass::freg), Abi::Scalar(s))
+        (RiscV(RiscVInlineAsmRegClass::freg), BackendRepr::Scalar(s))
             if s.primitive() == Primitive::Float(Float::F16)
                 && !any_target_feature_enabled(bx, instance, &[sym::zfhmin, sym::zfh]) =>
         {
@@ -1022,15 +1025,15 @@ fn llvm_fixup_output<'ll, 'tcx>(
     instance: Instance<'_>,
 ) -> &'ll Value {
     use InlineAsmRegClass::*;
-    match (reg, layout.abi) {
-        (AArch64(AArch64InlineAsmRegClass::vreg), Abi::Scalar(s)) => {
+    match (reg, layout.backend_repr) {
+        (AArch64(AArch64InlineAsmRegClass::vreg), BackendRepr::Scalar(s)) => {
             if let Primitive::Int(Integer::I8, _) = s.primitive() {
                 bx.extract_element(value, bx.const_i32(0))
             } else {
                 value
             }
         }
-        (AArch64(AArch64InlineAsmRegClass::vreg_low16), Abi::Scalar(s))
+        (AArch64(AArch64InlineAsmRegClass::vreg_low16), BackendRepr::Scalar(s))
             if s.primitive() != Primitive::Float(Float::F128) =>
         {
             value = bx.extract_element(value, bx.const_i32(0));
@@ -1039,7 +1042,7 @@ fn llvm_fixup_output<'ll, 'tcx>(
             }
             value
         }
-        (AArch64(AArch64InlineAsmRegClass::vreg_low16), Abi::Vector { element, count })
+        (AArch64(AArch64InlineAsmRegClass::vreg_low16), BackendRepr::Vector { element, count })
             if layout.size.bytes() == 8 =>
         {
             let elem_ty = llvm_asm_scalar_type(bx.cx, element);
@@ -1047,14 +1050,14 @@ fn llvm_fixup_output<'ll, 'tcx>(
             let indices: Vec<_> = (0..count).map(|x| bx.const_i32(x as i32)).collect();
             bx.shuffle_vector(value, bx.const_undef(vec_ty), bx.const_vector(&indices))
         }
-        (X86(X86InlineAsmRegClass::reg_abcd), Abi::Scalar(s))
+        (X86(X86InlineAsmRegClass::reg_abcd), BackendRepr::Scalar(s))
             if s.primitive() == Primitive::Float(Float::F64) =>
         {
             bx.bitcast(value, bx.cx.type_f64())
         }
         (
             X86(X86InlineAsmRegClass::xmm_reg | X86InlineAsmRegClass::zmm_reg),
-            Abi::Vector { .. },
+            BackendRepr::Vector { .. },
         ) if layout.size.bytes() == 64 => bx.bitcast(value, layout.llvm_type(bx.cx)),
         (
             X86(
@@ -1062,7 +1065,7 @@ fn llvm_fixup_output<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) if bx.sess().asm_arch == Some(InlineAsmArch::X86)
             && s.primitive() == Primitive::Float(Float::F128) =>
         {
@@ -1074,7 +1077,7 @@ fn llvm_fixup_output<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) if s.primitive() == Primitive::Float(Float::F16) => {
             let value = bx.bitcast(value, bx.type_vector(bx.type_f16(), 8));
             bx.extract_element(value, bx.const_usize(0))
@@ -1085,11 +1088,14 @@ fn llvm_fixup_output<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Vector { element, count: count @ (8 | 16) },
+            BackendRepr::Vector { element, count: count @ (8 | 16) },
         ) if element.primitive() == Primitive::Float(Float::F16) => {
             bx.bitcast(value, bx.type_vector(bx.type_f16(), count))
         }
-        (Arm(ArmInlineAsmRegClass::sreg | ArmInlineAsmRegClass::sreg_low16), Abi::Scalar(s)) => {
+        (
+            Arm(ArmInlineAsmRegClass::sreg | ArmInlineAsmRegClass::sreg_low16),
+            BackendRepr::Scalar(s),
+        ) => {
             if let Primitive::Int(Integer::I32, _) = s.primitive() {
                 bx.bitcast(value, bx.cx.type_i32())
             } else {
@@ -1102,7 +1108,7 @@ fn llvm_fixup_output<'ll, 'tcx>(
                 | ArmInlineAsmRegClass::dreg_low8
                 | ArmInlineAsmRegClass::dreg_low16,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) => {
             if let Primitive::Int(Integer::I64, _) = s.primitive() {
                 bx.bitcast(value, bx.cx.type_i64())
@@ -1119,11 +1125,11 @@ fn llvm_fixup_output<'ll, 'tcx>(
                 | ArmInlineAsmRegClass::qreg_low4
                 | ArmInlineAsmRegClass::qreg_low8,
             ),
-            Abi::Vector { element, count: count @ (4 | 8) },
+            BackendRepr::Vector { element, count: count @ (4 | 8) },
         ) if element.primitive() == Primitive::Float(Float::F16) => {
             bx.bitcast(value, bx.type_vector(bx.type_f16(), count))
         }
-        (Mips(MipsInlineAsmRegClass::reg), Abi::Scalar(s)) => {
+        (Mips(MipsInlineAsmRegClass::reg), BackendRepr::Scalar(s)) => {
             match s.primitive() {
                 // MIPS only supports register-length arithmetics.
                 Primitive::Int(Integer::I8, _) => bx.trunc(value, bx.cx.type_i8()),
@@ -1133,7 +1139,7 @@ fn llvm_fixup_output<'ll, 'tcx>(
                 _ => value,
             }
         }
-        (RiscV(RiscVInlineAsmRegClass::freg), Abi::Scalar(s))
+        (RiscV(RiscVInlineAsmRegClass::freg), BackendRepr::Scalar(s))
             if s.primitive() == Primitive::Float(Float::F16)
                 && !any_target_feature_enabled(bx, instance, &[sym::zfhmin, sym::zfh]) =>
         {
@@ -1153,35 +1159,35 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
     instance: Instance<'_>,
 ) -> &'ll Type {
     use InlineAsmRegClass::*;
-    match (reg, layout.abi) {
-        (AArch64(AArch64InlineAsmRegClass::vreg), Abi::Scalar(s)) => {
+    match (reg, layout.backend_repr) {
+        (AArch64(AArch64InlineAsmRegClass::vreg), BackendRepr::Scalar(s)) => {
             if let Primitive::Int(Integer::I8, _) = s.primitive() {
                 cx.type_vector(cx.type_i8(), 8)
             } else {
                 layout.llvm_type(cx)
             }
         }
-        (AArch64(AArch64InlineAsmRegClass::vreg_low16), Abi::Scalar(s))
+        (AArch64(AArch64InlineAsmRegClass::vreg_low16), BackendRepr::Scalar(s))
             if s.primitive() != Primitive::Float(Float::F128) =>
         {
             let elem_ty = llvm_asm_scalar_type(cx, s);
             let count = 16 / layout.size.bytes();
             cx.type_vector(elem_ty, count)
         }
-        (AArch64(AArch64InlineAsmRegClass::vreg_low16), Abi::Vector { element, count })
+        (AArch64(AArch64InlineAsmRegClass::vreg_low16), BackendRepr::Vector { element, count })
             if layout.size.bytes() == 8 =>
         {
             let elem_ty = llvm_asm_scalar_type(cx, element);
             cx.type_vector(elem_ty, count * 2)
         }
-        (X86(X86InlineAsmRegClass::reg_abcd), Abi::Scalar(s))
+        (X86(X86InlineAsmRegClass::reg_abcd), BackendRepr::Scalar(s))
             if s.primitive() == Primitive::Float(Float::F64) =>
         {
             cx.type_i64()
         }
         (
             X86(X86InlineAsmRegClass::xmm_reg | X86InlineAsmRegClass::zmm_reg),
-            Abi::Vector { .. },
+            BackendRepr::Vector { .. },
         ) if layout.size.bytes() == 64 => cx.type_vector(cx.type_f64(), 8),
         (
             X86(
@@ -1189,7 +1195,7 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) if cx.sess().asm_arch == Some(InlineAsmArch::X86)
             && s.primitive() == Primitive::Float(Float::F128) =>
         {
@@ -1201,7 +1207,7 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) if s.primitive() == Primitive::Float(Float::F16) => cx.type_vector(cx.type_i16(), 8),
         (
             X86(
@@ -1209,11 +1215,14 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
                 | X86InlineAsmRegClass::ymm_reg
                 | X86InlineAsmRegClass::zmm_reg,
             ),
-            Abi::Vector { element, count: count @ (8 | 16) },
+            BackendRepr::Vector { element, count: count @ (8 | 16) },
         ) if element.primitive() == Primitive::Float(Float::F16) => {
             cx.type_vector(cx.type_i16(), count)
         }
-        (Arm(ArmInlineAsmRegClass::sreg | ArmInlineAsmRegClass::sreg_low16), Abi::Scalar(s)) => {
+        (
+            Arm(ArmInlineAsmRegClass::sreg | ArmInlineAsmRegClass::sreg_low16),
+            BackendRepr::Scalar(s),
+        ) => {
             if let Primitive::Int(Integer::I32, _) = s.primitive() {
                 cx.type_f32()
             } else {
@@ -1226,7 +1235,7 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
                 | ArmInlineAsmRegClass::dreg_low8
                 | ArmInlineAsmRegClass::dreg_low16,
             ),
-            Abi::Scalar(s),
+            BackendRepr::Scalar(s),
         ) => {
             if let Primitive::Int(Integer::I64, _) = s.primitive() {
                 cx.type_f64()
@@ -1243,11 +1252,11 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
                 | ArmInlineAsmRegClass::qreg_low4
                 | ArmInlineAsmRegClass::qreg_low8,
             ),
-            Abi::Vector { element, count: count @ (4 | 8) },
+            BackendRepr::Vector { element, count: count @ (4 | 8) },
         ) if element.primitive() == Primitive::Float(Float::F16) => {
             cx.type_vector(cx.type_i16(), count)
         }
-        (Mips(MipsInlineAsmRegClass::reg), Abi::Scalar(s)) => {
+        (Mips(MipsInlineAsmRegClass::reg), BackendRepr::Scalar(s)) => {
             match s.primitive() {
                 // MIPS only supports register-length arithmetics.
                 Primitive::Int(Integer::I8 | Integer::I16, _) => cx.type_i32(),
@@ -1256,7 +1265,7 @@ fn llvm_fixup_output_type<'ll, 'tcx>(
                 _ => layout.llvm_type(cx),
             }
         }
-        (RiscV(RiscVInlineAsmRegClass::freg), Abi::Scalar(s))
+        (RiscV(RiscVInlineAsmRegClass::freg), BackendRepr::Scalar(s))
             if s.primitive() == Primitive::Float(Float::F16)
                 && !any_target_feature_enabled(cx, instance, &[sym::zfhmin, sym::zfh]) =>
         {
diff --git a/compiler/rustc_codegen_llvm/src/back/lto.rs b/compiler/rustc_codegen_llvm/src/back/lto.rs
index 02149e176eabe..48beb9be2b2a1 100644
--- a/compiler/rustc_codegen_llvm/src/back/lto.rs
+++ b/compiler/rustc_codegen_llvm/src/back/lto.rs
@@ -165,13 +165,14 @@ fn get_bitcode_slice_from_object_data<'a>(
     // We drop the "__LLVM," prefix here because on Apple platforms there's a notion of "segment
     // name" which in the public API for sections gets treated as part of the section name, but
     // internally in MachOObjectFile.cpp gets treated separately.
-    let section_name = bitcode_section_name(cgcx).trim_start_matches("__LLVM,");
+    let section_name = bitcode_section_name(cgcx).to_str().unwrap().trim_start_matches("__LLVM,");
     let mut len = 0;
     let data = unsafe {
         llvm::LLVMRustGetSliceFromObjectDataByName(
             obj.as_ptr(),
             obj.len(),
             section_name.as_ptr(),
+            section_name.len(),
             &mut len,
         )
     };
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index e68ba96f14f91..bfa9e8b82a033 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -1,4 +1,4 @@
-use std::ffi::CString;
+use std::ffi::{CStr, CString};
 use std::io::{self, Write};
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
@@ -958,14 +958,13 @@ fn target_is_aix(cgcx: &CodegenContext<LlvmCodegenBackend>) -> bool {
     cgcx.opts.target_triple.triple().contains("-aix")
 }
 
-//FIXME use c string literals here too
-pub(crate) fn bitcode_section_name(cgcx: &CodegenContext<LlvmCodegenBackend>) -> &'static str {
+pub(crate) fn bitcode_section_name(cgcx: &CodegenContext<LlvmCodegenBackend>) -> &'static CStr {
     if target_is_apple(cgcx) {
-        "__LLVM,__bitcode\0"
+        c"__LLVM,__bitcode"
     } else if target_is_aix(cgcx) {
-        ".ipa\0"
+        c".ipa"
     } else {
-        ".llvmbc\0"
+        c".llvmbc"
     }
 }
 
@@ -1042,8 +1041,7 @@ unsafe fn embed_bitcode(
             );
             llvm::LLVMSetInitializer(llglobal, llconst);
 
-            let section = bitcode_section_name(cgcx);
-            llvm::LLVMSetSection(llglobal, section.as_c_char_ptr());
+            llvm::set_section(llglobal, bitcode_section_name(cgcx));
             llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage);
             llvm::LLVMSetGlobalConstant(llglobal, llvm::True);
 
@@ -1061,7 +1059,7 @@ unsafe fn embed_bitcode(
             } else {
                 c".llvmcmd"
             };
-            llvm::LLVMSetSection(llglobal, section.as_ptr());
+            llvm::set_section(llglobal, section);
             llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage);
         } else {
             // We need custom section flags, so emit module-level inline assembly.
diff --git a/compiler/rustc_codegen_llvm/src/base.rs b/compiler/rustc_codegen_llvm/src/base.rs
index 0ba8d82406a82..3279389479499 100644
--- a/compiler/rustc_codegen_llvm/src/base.rs
+++ b/compiler/rustc_codegen_llvm/src/base.rs
@@ -145,10 +145,8 @@ pub(crate) fn compile_codegen_unit(
 
 pub(crate) fn set_link_section(llval: &Value, attrs: &CodegenFnAttrs) {
     let Some(sect) = attrs.link_section else { return };
-    unsafe {
-        let buf = SmallCStr::new(sect.as_str());
-        llvm::LLVMSetSection(llval, buf.as_ptr());
-    }
+    let buf = SmallCStr::new(sect.as_str());
+    llvm::set_section(llval, &buf);
 }
 
 pub(crate) fn linkage_to_llvm(linkage: Linkage) -> llvm::Linkage {
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index 8702532c36eee..8e87869f94618 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -545,13 +545,13 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
             }
             let llval = const_llval.unwrap_or_else(|| {
                 let load = self.load(llty, place.val.llval, place.val.align);
-                if let abi::Abi::Scalar(scalar) = place.layout.abi {
+                if let abi::BackendRepr::Scalar(scalar) = place.layout.backend_repr {
                     scalar_load_metadata(self, load, scalar, place.layout, Size::ZERO);
                 }
                 load
             });
             OperandValue::Immediate(self.to_immediate(llval, place.layout))
-        } else if let abi::Abi::ScalarPair(a, b) = place.layout.abi {
+        } else if let abi::BackendRepr::ScalarPair(a, b) = place.layout.backend_repr {
             let b_offset = a.size(self).align_to(b.align(self).abi);
 
             let mut load = |i, scalar: abi::Scalar, layout, align, offset| {
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index f33da42d63e87..9778ff4918c0d 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -565,7 +565,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
             let g = llvm::LLVMAddGlobal(self.llmod, self.val_ty(array), name.as_ptr());
             llvm::LLVMSetInitializer(g, array);
             llvm::set_linkage(g, llvm::Linkage::AppendingLinkage);
-            llvm::LLVMSetSection(g, c"llvm.metadata".as_ptr());
+            llvm::set_section(g, c"llvm.metadata");
         }
     }
 }
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs b/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs
index 7947c9c8c8efd..aef8642f1998a 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs
@@ -72,7 +72,7 @@ pub(crate) fn get_or_insert_gdb_debug_scripts_section_global<'ll>(
             let section_var = cx
                 .define_global(section_var_name, llvm_type)
                 .unwrap_or_else(|| bug!("symbol `{}` is already defined", section_var_name));
-            llvm::LLVMSetSection(section_var, c".debug_gdb_scripts".as_ptr());
+            llvm::set_section(section_var, c".debug_gdb_scripts");
             llvm::LLVMSetInitializer(section_var, cx.const_bytes(section_contents));
             llvm::LLVMSetGlobalConstant(section_var, llvm::True);
             llvm::LLVMSetUnnamedAddress(section_var, llvm::UnnamedAddr::Global);
diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs
index d04b525761942..c77e00aed9ac5 100644
--- a/compiler/rustc_codegen_llvm/src/intrinsic.rs
+++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs
@@ -258,8 +258,8 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
                 self.call_intrinsic("llvm.va_copy", &[args[0].immediate(), args[1].immediate()])
             }
             sym::va_arg => {
-                match fn_abi.ret.layout.abi {
-                    abi::Abi::Scalar(scalar) => {
+                match fn_abi.ret.layout.backend_repr {
+                    abi::BackendRepr::Scalar(scalar) => {
                         match scalar.primitive() {
                             Primitive::Int(..) => {
                                 if self.cx().size_of(ret_ty).bytes() < 4 {
@@ -436,13 +436,13 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
             }
 
             sym::raw_eq => {
-                use abi::Abi::*;
+                use abi::BackendRepr::*;
                 let tp_ty = fn_args.type_at(0);
                 let layout = self.layout_of(tp_ty).layout;
-                let use_integer_compare = match layout.abi() {
+                let use_integer_compare = match layout.backend_repr() {
                     Scalar(_) | ScalarPair(_, _) => true,
                     Uninhabited | Vector { .. } => false,
-                    Aggregate { .. } => {
+                    Memory { .. } => {
                         // For rusty ABIs, small aggregates are actually passed
                         // as `RegKind::Integer` (see `FnAbi::adjust_for_abi`),
                         // so we re-use that same threshold here.
@@ -549,7 +549,8 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
                 }
 
                 let llret_ty = if ret_ty.is_simd()
-                    && let abi::Abi::Aggregate { .. } = self.layout_of(ret_ty).layout.abi
+                    && let abi::BackendRepr::Memory { .. } =
+                        self.layout_of(ret_ty).layout.backend_repr
                 {
                     let (size, elem_ty) = ret_ty.simd_size_and_type(self.tcx());
                     let elem_ll_ty = match elem_ty.kind() {
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 888d41d472668..c0ca7e5102509 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -2416,6 +2416,7 @@ unsafe extern "C" {
         data: *const u8,
         len: usize,
         name: *const u8,
+        name_len: usize,
         out_len: &mut usize,
     ) -> *const u8;
 
diff --git a/compiler/rustc_codegen_llvm/src/type_of.rs b/compiler/rustc_codegen_llvm/src/type_of.rs
index 6be4c3f034f12..2b05e24a7babf 100644
--- a/compiler/rustc_codegen_llvm/src/type_of.rs
+++ b/compiler/rustc_codegen_llvm/src/type_of.rs
@@ -1,7 +1,7 @@
 use std::fmt::Write;
 
 use rustc_abi::Primitive::{Float, Int, Pointer};
-use rustc_abi::{Abi, Align, FieldsShape, Scalar, Size, Variants};
+use rustc_abi::{Align, BackendRepr, FieldsShape, Scalar, Size, Variants};
 use rustc_codegen_ssa::traits::*;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
@@ -17,13 +17,13 @@ fn uncached_llvm_type<'a, 'tcx>(
     layout: TyAndLayout<'tcx>,
     defer: &mut Option<(&'a Type, TyAndLayout<'tcx>)>,
 ) -> &'a Type {
-    match layout.abi {
-        Abi::Scalar(_) => bug!("handled elsewhere"),
-        Abi::Vector { element, count } => {
+    match layout.backend_repr {
+        BackendRepr::Scalar(_) => bug!("handled elsewhere"),
+        BackendRepr::Vector { element, count } => {
             let element = layout.scalar_llvm_type_at(cx, element);
             return cx.type_vector(element, count);
         }
-        Abi::Uninhabited | Abi::Aggregate { .. } | Abi::ScalarPair(..) => {}
+        BackendRepr::Uninhabited | BackendRepr::Memory { .. } | BackendRepr::ScalarPair(..) => {}
     }
 
     let name = match layout.ty.kind() {
@@ -170,16 +170,21 @@ pub(crate) trait LayoutLlvmExt<'tcx> {
 
 impl<'tcx> LayoutLlvmExt<'tcx> for TyAndLayout<'tcx> {
     fn is_llvm_immediate(&self) -> bool {
-        match self.abi {
-            Abi::Scalar(_) | Abi::Vector { .. } => true,
-            Abi::ScalarPair(..) | Abi::Uninhabited | Abi::Aggregate { .. } => false,
+        match self.backend_repr {
+            BackendRepr::Scalar(_) | BackendRepr::Vector { .. } => true,
+            BackendRepr::ScalarPair(..) | BackendRepr::Uninhabited | BackendRepr::Memory { .. } => {
+                false
+            }
         }
     }
 
     fn is_llvm_scalar_pair(&self) -> bool {
-        match self.abi {
-            Abi::ScalarPair(..) => true,
-            Abi::Uninhabited | Abi::Scalar(_) | Abi::Vector { .. } | Abi::Aggregate { .. } => false,
+        match self.backend_repr {
+            BackendRepr::ScalarPair(..) => true,
+            BackendRepr::Uninhabited
+            | BackendRepr::Scalar(_)
+            | BackendRepr::Vector { .. }
+            | BackendRepr::Memory { .. } => false,
         }
     }
 
@@ -198,7 +203,7 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyAndLayout<'tcx> {
         // This must produce the same result for `repr(transparent)` wrappers as for the inner type!
         // In other words, this should generally not look at the type at all, but only at the
         // layout.
-        if let Abi::Scalar(scalar) = self.abi {
+        if let BackendRepr::Scalar(scalar) = self.backend_repr {
             // Use a different cache for scalars because pointers to DSTs
             // can be either wide or thin (data pointers of wide pointers).
             if let Some(&llty) = cx.scalar_lltypes.borrow().get(&self.ty) {
@@ -248,13 +253,13 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyAndLayout<'tcx> {
     }
 
     fn immediate_llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> &'a Type {
-        match self.abi {
-            Abi::Scalar(scalar) => {
+        match self.backend_repr {
+            BackendRepr::Scalar(scalar) => {
                 if scalar.is_bool() {
                     return cx.type_i1();
                 }
             }
-            Abi::ScalarPair(..) => {
+            BackendRepr::ScalarPair(..) => {
                 // An immediate pair always contains just the two elements, without any padding
                 // filler, as it should never be stored to memory.
                 return cx.type_struct(
@@ -287,7 +292,7 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyAndLayout<'tcx> {
         // This must produce the same result for `repr(transparent)` wrappers as for the inner type!
         // In other words, this should generally not look at the type at all, but only at the
         // layout.
-        let Abi::ScalarPair(a, b) = self.abi else {
+        let BackendRepr::ScalarPair(a, b) = self.backend_repr else {
             bug!("TyAndLayout::scalar_pair_element_llty({:?}): not applicable", self);
         };
         let scalar = [a, b][index];
diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
index b954633f4532d..cb4c9c078b197 100644
--- a/compiler/rustc_codegen_ssa/src/base.rs
+++ b/compiler/rustc_codegen_ssa/src/base.rs
@@ -21,7 +21,7 @@ use rustc_middle::mir::BinOp;
 use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder, MonoItem};
 use rustc_middle::query::Providers;
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout};
-use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
+use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypingMode};
 use rustc_session::Session;
 use rustc_session::config::{self, CrateType, EntryFnType, OptLevel, OutputType};
 use rustc_span::symbol::sym;
@@ -119,7 +119,7 @@ pub fn validate_trivial_unsize<'tcx>(
 ) -> bool {
     match (source_data.principal(), target_data.principal()) {
         (Some(hr_source_principal), Some(hr_target_principal)) => {
-            let infcx = tcx.infer_ctxt().build();
+            let infcx = tcx.infer_ctxt().build(TypingMode::PostAnalysis);
             let universe = infcx.universe();
             let ocx = ObligationCtxt::new(&infcx);
             infcx.enter_forall(hr_target_principal, |target_principal| {
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index a17a127f01491..283740fa66438 100644
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -1532,7 +1532,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 // the load would just produce `OperandValue::Ref` instead
                 // of the `OperandValue::Immediate` we need for the call.
                 llval = bx.load(bx.backend_type(arg.layout), llval, align);
-                if let abi::Abi::Scalar(scalar) = arg.layout.abi {
+                if let abi::BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
                     if scalar.is_bool() {
                         bx.range_metadata(llval, WrappingRange { start: 0, end: 1 });
                     }
diff --git a/compiler/rustc_codegen_ssa/src/mir/constant.rs b/compiler/rustc_codegen_ssa/src/mir/constant.rs
index 15f45b226f5e4..54b9c9cc89f51 100644
--- a/compiler/rustc_codegen_ssa/src/mir/constant.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/constant.rs
@@ -1,8 +1,8 @@
+use rustc_abi::BackendRepr;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::ty::layout::HasTyCtxt;
 use rustc_middle::ty::{self, Ty};
 use rustc_middle::{bug, mir, span_bug};
-use rustc_target::abi::Abi;
 
 use super::FunctionCx;
 use crate::errors;
@@ -86,7 +86,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     .map(|field| {
                         if let Some(prim) = field.try_to_scalar() {
                             let layout = bx.layout_of(field_ty);
-                            let Abi::Scalar(scalar) = layout.abi else {
+                            let BackendRepr::Scalar(scalar) = layout.backend_repr else {
                                 bug!("from_const: invalid ByVal layout: {:#?}", layout);
                             };
                             bx.scalar_to_backend(prim, scalar, bx.immediate_backend_type(layout))
diff --git a/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs b/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs
index 146f55f95c21a..21d20475408b2 100644
--- a/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs
@@ -2,6 +2,7 @@ use std::collections::hash_map::Entry;
 use std::marker::PhantomData;
 use std::ops::Range;
 
+use rustc_abi::{BackendRepr, FieldIdx, FieldsShape, Size, VariantIdx};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::IndexVec;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
@@ -11,7 +12,6 @@ use rustc_middle::{bug, mir, ty};
 use rustc_session::config::DebugInfo;
 use rustc_span::symbol::{Symbol, kw};
 use rustc_span::{BytePos, Span, hygiene};
-use rustc_target::abi::{Abi, FieldIdx, FieldsShape, Size, VariantIdx};
 
 use super::operand::{OperandRef, OperandValue};
 use super::place::{PlaceRef, PlaceValue};
@@ -510,7 +510,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         // be marked as a `LocalVariable` for MSVC debuggers to visualize
                         // their data correctly. (See #81894 & #88625)
                         let var_ty_layout = self.cx.layout_of(var_ty);
-                        if let Abi::ScalarPair(_, _) = var_ty_layout.abi {
+                        if let BackendRepr::ScalarPair(_, _) = var_ty_layout.backend_repr {
                             VariableKind::LocalVariable
                         } else {
                             VariableKind::ArgumentVariable(arg_index)
diff --git a/compiler/rustc_codegen_ssa/src/mir/operand.rs b/compiler/rustc_codegen_ssa/src/mir/operand.rs
index 88ceff327d0aa..19101ec2d1ba3 100644
--- a/compiler/rustc_codegen_ssa/src/mir/operand.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/operand.rs
@@ -4,7 +4,7 @@ use std::fmt;
 use arrayvec::ArrayVec;
 use either::Either;
 use rustc_abi as abi;
-use rustc_abi::{Abi, Align, Size};
+use rustc_abi::{Align, BackendRepr, Size};
 use rustc_middle::bug;
 use rustc_middle::mir::interpret::{Pointer, Scalar, alloc_range};
 use rustc_middle::mir::{self, ConstValue};
@@ -163,7 +163,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
 
         let val = match val {
             ConstValue::Scalar(x) => {
-                let Abi::Scalar(scalar) = layout.abi else {
+                let BackendRepr::Scalar(scalar) = layout.backend_repr else {
                     bug!("from_const: invalid ByVal layout: {:#?}", layout);
                 };
                 let llval = bx.scalar_to_backend(x, scalar, bx.immediate_backend_type(layout));
@@ -171,7 +171,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
             }
             ConstValue::ZeroSized => return OperandRef::zero_sized(layout),
             ConstValue::Slice { data, meta } => {
-                let Abi::ScalarPair(a_scalar, _) = layout.abi else {
+                let BackendRepr::ScalarPair(a_scalar, _) = layout.backend_repr else {
                     bug!("from_const: invalid ScalarPair layout: {:#?}", layout);
                 };
                 let a = Scalar::from_pointer(
@@ -221,14 +221,14 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
         // case where some of the bytes are initialized and others are not. So, we need an extra
         // check that walks over the type of `mplace` to make sure it is truly correct to treat this
         // like a `Scalar` (or `ScalarPair`).
-        match layout.abi {
-            Abi::Scalar(s @ abi::Scalar::Initialized { .. }) => {
+        match layout.backend_repr {
+            BackendRepr::Scalar(s @ abi::Scalar::Initialized { .. }) => {
                 let size = s.size(bx);
                 assert_eq!(size, layout.size, "abi::Scalar size does not match layout size");
                 let val = read_scalar(offset, size, s, bx.immediate_backend_type(layout));
                 OperandRef { val: OperandValue::Immediate(val), layout }
             }
-            Abi::ScalarPair(
+            BackendRepr::ScalarPair(
                 a @ abi::Scalar::Initialized { .. },
                 b @ abi::Scalar::Initialized { .. },
             ) => {
@@ -322,7 +322,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
         llval: V,
         layout: TyAndLayout<'tcx>,
     ) -> Self {
-        let val = if let Abi::ScalarPair(..) = layout.abi {
+        let val = if let BackendRepr::ScalarPair(..) = layout.backend_repr {
             debug!("Operand::from_immediate_or_packed_pair: unpacking {:?} @ {:?}", llval, layout);
 
             // Deconstruct the immediate aggregate.
@@ -343,7 +343,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
         let field = self.layout.field(bx.cx(), i);
         let offset = self.layout.fields.offset(i);
 
-        let mut val = match (self.val, self.layout.abi) {
+        let mut val = match (self.val, self.layout.backend_repr) {
             // If the field is ZST, it has no data.
             _ if field.is_zst() => OperandValue::ZeroSized,
 
@@ -356,7 +356,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
             }
 
             // Extract a scalar component from a pair.
-            (OperandValue::Pair(a_llval, b_llval), Abi::ScalarPair(a, b)) => {
+            (OperandValue::Pair(a_llval, b_llval), BackendRepr::ScalarPair(a, b)) => {
                 if offset.bytes() == 0 {
                     assert_eq!(field.size, a.size(bx.cx()));
                     OperandValue::Immediate(a_llval)
@@ -368,30 +368,30 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
             }
 
             // `#[repr(simd)]` types are also immediate.
-            (OperandValue::Immediate(llval), Abi::Vector { .. }) => {
+            (OperandValue::Immediate(llval), BackendRepr::Vector { .. }) => {
                 OperandValue::Immediate(bx.extract_element(llval, bx.cx().const_usize(i as u64)))
             }
 
             _ => bug!("OperandRef::extract_field({:?}): not applicable", self),
         };
 
-        match (&mut val, field.abi) {
+        match (&mut val, field.backend_repr) {
             (OperandValue::ZeroSized, _) => {}
             (
                 OperandValue::Immediate(llval),
-                Abi::Scalar(_) | Abi::ScalarPair(..) | Abi::Vector { .. },
+                BackendRepr::Scalar(_) | BackendRepr::ScalarPair(..) | BackendRepr::Vector { .. },
             ) => {
                 // Bools in union fields needs to be truncated.
                 *llval = bx.to_immediate(*llval, field);
             }
-            (OperandValue::Pair(a, b), Abi::ScalarPair(a_abi, b_abi)) => {
+            (OperandValue::Pair(a, b), BackendRepr::ScalarPair(a_abi, b_abi)) => {
                 // Bools in union fields needs to be truncated.
                 *a = bx.to_immediate_scalar(*a, a_abi);
                 *b = bx.to_immediate_scalar(*b, b_abi);
             }
             // Newtype vector of array, e.g. #[repr(simd)] struct S([i32; 4]);
-            (OperandValue::Immediate(llval), Abi::Aggregate { sized: true }) => {
-                assert_matches!(self.layout.abi, Abi::Vector { .. });
+            (OperandValue::Immediate(llval), BackendRepr::Memory { sized: true }) => {
+                assert_matches!(self.layout.backend_repr, BackendRepr::Vector { .. });
 
                 let llfield_ty = bx.cx().backend_type(field);
 
@@ -400,7 +400,10 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
                 bx.store(*llval, llptr, field.align.abi);
                 *llval = bx.load(llfield_ty, llptr, field.align.abi);
             }
-            (OperandValue::Immediate(_), Abi::Uninhabited | Abi::Aggregate { sized: false }) => {
+            (
+                OperandValue::Immediate(_),
+                BackendRepr::Uninhabited | BackendRepr::Memory { sized: false },
+            ) => {
                 bug!()
             }
             (OperandValue::Pair(..), _) => bug!(),
@@ -494,7 +497,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandValue<V> {
                 bx.store_with_flags(val, dest.val.llval, dest.val.align, flags);
             }
             OperandValue::Pair(a, b) => {
-                let Abi::ScalarPair(a_scalar, b_scalar) = dest.layout.abi else {
+                let BackendRepr::ScalarPair(a_scalar, b_scalar) = dest.layout.backend_repr else {
                     bug!("store_with_flags: invalid ScalarPair layout: {:#?}", dest.layout);
                 };
                 let b_offset = a_scalar.size(bx).align_to(b_scalar.align(bx).abi);
@@ -645,7 +648,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     // However, some SIMD types do not actually use the vector ABI
                     // (in particular, packed SIMD types do not). Ensure we exclude those.
                     let layout = bx.layout_of(constant_ty);
-                    if let Abi::Vector { .. } = layout.abi {
+                    if let BackendRepr::Vector { .. } = layout.backend_repr {
                         let (llval, ty) = self.immediate_const_vector(bx, constant);
                         return OperandRef {
                             val: OperandValue::Immediate(llval),
diff --git a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
index 6e8c193cd7589..86cf0f9614d3e 100644
--- a/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/rvalue.rs
@@ -1136,17 +1136,17 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             OperandValueKind::ZeroSized
         } else if self.cx.is_backend_immediate(layout) {
             assert!(!self.cx.is_backend_scalar_pair(layout));
-            OperandValueKind::Immediate(match layout.abi {
-                abi::Abi::Scalar(s) => s,
-                abi::Abi::Vector { element, .. } => element,
+            OperandValueKind::Immediate(match layout.backend_repr {
+                abi::BackendRepr::Scalar(s) => s,
+                abi::BackendRepr::Vector { element, .. } => element,
                 x => span_bug!(self.mir.span, "Couldn't translate {x:?} as backend immediate"),
             })
         } else if self.cx.is_backend_scalar_pair(layout) {
-            let abi::Abi::ScalarPair(s1, s2) = layout.abi else {
+            let abi::BackendRepr::ScalarPair(s1, s2) = layout.backend_repr else {
                 span_bug!(
                     self.mir.span,
                     "Couldn't translate {:?} as backend scalar pair",
-                    layout.abi,
+                    layout.backend_repr,
                 );
             };
             OperandValueKind::Pair(s1, s2)
diff --git a/compiler/rustc_codegen_ssa/src/traits/builder.rs b/compiler/rustc_codegen_ssa/src/traits/builder.rs
index 50a5171414695..768a0439ab51b 100644
--- a/compiler/rustc_codegen_ssa/src/traits/builder.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/builder.rs
@@ -1,13 +1,13 @@
 use std::assert_matches::assert_matches;
 use std::ops::Deref;
 
+use rustc_abi::{Align, BackendRepr, Scalar, Size, WrappingRange};
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{Instance, Ty};
 use rustc_session::config::OptLevel;
 use rustc_span::Span;
 use rustc_target::abi::call::FnAbi;
-use rustc_target::abi::{Abi, Align, Scalar, Size, WrappingRange};
 
 use super::abi::AbiBuilderMethods;
 use super::asm::AsmBuilderMethods;
@@ -162,7 +162,7 @@ pub trait BuilderMethods<'a, 'tcx>:
 
     fn from_immediate(&mut self, val: Self::Value) -> Self::Value;
     fn to_immediate(&mut self, val: Self::Value, layout: TyAndLayout<'_>) -> Self::Value {
-        if let Abi::Scalar(scalar) = layout.abi {
+        if let BackendRepr::Scalar(scalar) = layout.backend_repr {
             self.to_immediate_scalar(val, scalar)
         } else {
             val
diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs
index 004fb12419f11..5210241d5e49e 100644
--- a/compiler/rustc_const_eval/src/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/check_consts/check.rs
@@ -16,7 +16,7 @@ use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::*;
 use rustc_middle::span_bug;
 use rustc_middle::ty::adjustment::PointerCoercion;
-use rustc_middle::ty::{self, Instance, InstanceKind, Ty, TypeVisitableExt};
+use rustc_middle::ty::{self, Instance, InstanceKind, Ty, TypeVisitableExt, TypingMode};
 use rustc_mir_dataflow::Analysis;
 use rustc_mir_dataflow::impls::MaybeStorageLive;
 use rustc_mir_dataflow::storage::always_storage_live_locals;
@@ -64,8 +64,7 @@ impl<'mir, 'tcx> Qualifs<'mir, 'tcx> {
             let ConstCx { tcx, body, .. } = *ccx;
 
             FlowSensitiveAnalysis::new(NeedsDrop, ccx)
-                .into_engine(tcx, body)
-                .iterate_to_fixpoint()
+                .iterate_to_fixpoint(tcx, body, None)
                 .into_results_cursor(body)
         });
 
@@ -94,8 +93,7 @@ impl<'mir, 'tcx> Qualifs<'mir, 'tcx> {
             let ConstCx { tcx, body, .. } = *ccx;
 
             FlowSensitiveAnalysis::new(NeedsNonConstDrop, ccx)
-                .into_engine(tcx, body)
-                .iterate_to_fixpoint()
+                .iterate_to_fixpoint(tcx, body, None)
                 .into_results_cursor(body)
         });
 
@@ -124,8 +122,7 @@ impl<'mir, 'tcx> Qualifs<'mir, 'tcx> {
             let ConstCx { tcx, body, .. } = *ccx;
 
             FlowSensitiveAnalysis::new(HasMutInterior, ccx)
-                .into_engine(tcx, body)
-                .iterate_to_fixpoint()
+                .iterate_to_fixpoint(tcx, body, None)
                 .into_results_cursor(body)
         });
 
@@ -240,8 +237,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
                 let always_live_locals = &always_storage_live_locals(&ccx.body);
                 let mut maybe_storage_live =
                     MaybeStorageLive::new(Cow::Borrowed(always_live_locals))
-                        .into_engine(ccx.tcx, &ccx.body)
-                        .iterate_to_fixpoint()
+                        .iterate_to_fixpoint(ccx.tcx, &ccx.body, None)
                         .into_results_cursor(&ccx.body);
 
                 // And then check all `Return` in the MIR, and if a local is "maybe live" at a
@@ -593,7 +589,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                 // Typeck only does a "non-const" check since it operates on HIR and cannot distinguish
                 // which path expressions are getting called on and which path expressions are only used
                 // as function pointers. This is required for correctness.
-                let infcx = tcx.infer_ctxt().build();
+                let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
                 let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
                 let predicates = tcx.predicates_of(callee).instantiate(tcx, fn_args);
diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs
index 3ac06ae64910c..3f977dc4b05aa 100644
--- a/compiler/rustc_const_eval/src/check_consts/ops.rs
+++ b/compiler/rustc_const_eval/src/check_consts/ops.rs
@@ -12,7 +12,7 @@ use rustc_middle::mir::CallSource;
 use rustc_middle::span_bug;
 use rustc_middle::ty::print::{PrintTraitRefExt as _, with_no_trimmed_paths};
 use rustc_middle::ty::{
-    self, Closure, FnDef, FnPtr, GenericArgKind, GenericArgsRef, Param, TraitRef, Ty,
+    self, Closure, FnDef, FnPtr, GenericArgKind, GenericArgsRef, Param, TraitRef, Ty, TypingMode,
     suggest_constraining_type_param,
 };
 use rustc_middle::util::{CallDesugaringKind, CallKind, call_kind};
@@ -116,7 +116,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
                     let obligation =
                         Obligation::new(tcx, ObligationCause::dummy(), param_env, trait_ref);
 
-                    let infcx = tcx.infer_ctxt().build();
+                    let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
                     let mut selcx = SelectionContext::new(&infcx);
                     let implsrc = selcx.select(&obligation);
 
diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
index 547030a185435..e8637ba45cf1d 100644
--- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs
+++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
@@ -114,11 +114,11 @@ impl Qualif for HasMutInterior {
             ty::TraitRef::new(cx.tcx, freeze_def_id, [ty::GenericArg::from(ty)]),
         );
 
-        let infcx = cx
-            .tcx
-            .infer_ctxt()
-            .with_opaque_type_inference(cx.body.source.def_id().expect_local())
-            .build();
+        // FIXME(#132279): This should eventually use the already defined hidden types.
+        let infcx = cx.tcx.infer_ctxt().build(ty::TypingMode::analysis_in_body(
+            cx.tcx,
+            cx.body.source.def_id().expect_local(),
+        ));
         let ocx = ObligationCtxt::new(&infcx);
         ocx.register_obligation(obligation);
         let errors = ocx.select_all_or_error();
diff --git a/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs b/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs
index 743924faa21d8..bc2661c4fc71f 100644
--- a/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs
+++ b/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs
@@ -131,7 +131,7 @@ impl<'tcx> interpret::Machine<'tcx> for DummyMachine {
         interp_ok(match bin_op {
             Eq | Ne | Lt | Le | Gt | Ge => {
                 // Types can differ, e.g. fn ptrs with different `for`.
-                assert_eq!(left.layout.abi, right.layout.abi);
+                assert_eq!(left.layout.backend_repr, right.layout.backend_repr);
                 let size = ecx.pointer_size();
                 // Just compare the bits. ScalarPairs are compared lexicographically.
                 // We thus always compare pairs and simply fill scalars up with 0.
diff --git a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
index 7319c251bbd99..81b9d73b9528c 100644
--- a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
+++ b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
@@ -1,6 +1,7 @@
 use std::sync::atomic::Ordering::Relaxed;
 
 use either::{Left, Right};
+use rustc_abi::{self as abi, BackendRepr};
 use rustc_hir::def::DefKind;
 use rustc_middle::bug;
 use rustc_middle::mir::interpret::{AllocId, ErrorHandled, InterpErrorInfo};
@@ -12,7 +13,6 @@ use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::def_id::LocalDefId;
 use rustc_span::{DUMMY_SP, Span};
-use rustc_target::abi::{self, Abi};
 use tracing::{debug, instrument, trace};
 
 use super::{CanAccessMutGlobal, CompileTimeInterpCx, CompileTimeMachine};
@@ -174,8 +174,8 @@ pub(super) fn op_to_const<'tcx>(
     // type (it's used throughout the compiler and having it work just on literals is not enough)
     // and we want it to be fast (i.e., don't go to an `Allocation` and reconstruct the `Scalar`
     // from its byte-serialized form).
-    let force_as_immediate = match op.layout.abi {
-        Abi::Scalar(abi::Scalar::Initialized { .. }) => true,
+    let force_as_immediate = match op.layout.backend_repr {
+        BackendRepr::Scalar(abi::Scalar::Initialized { .. }) => true,
         // We don't *force* `ConstValue::Slice` for `ScalarPair`. This has the advantage that if the
         // input `op` is a place, then turning it into a `ConstValue` and back into a `OpTy` will
         // not have to generate any duplicate allocations (we preserve the original `AllocId` in
diff --git a/compiler/rustc_const_eval/src/const_eval/valtrees.rs b/compiler/rustc_const_eval/src/const_eval/valtrees.rs
index 9e80e666ba91b..ea88b2ed22e2f 100644
--- a/compiler/rustc_const_eval/src/const_eval/valtrees.rs
+++ b/compiler/rustc_const_eval/src/const_eval/valtrees.rs
@@ -1,10 +1,10 @@
+use rustc_abi::{BackendRepr, VariantIdx};
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_middle::mir::interpret::{EvalToValTreeResult, GlobalId};
 use rustc_middle::ty::layout::{LayoutCx, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt};
 use rustc_middle::{bug, mir};
 use rustc_span::DUMMY_SP;
-use rustc_target::abi::{Abi, VariantIdx};
 use tracing::{debug, instrument, trace};
 
 use super::eval_queries::{mk_eval_cx_to_read_const_val, op_to_const};
@@ -117,7 +117,7 @@ fn const_to_valtree_inner<'tcx>(
             let val = ecx.read_immediate(place).unwrap();
             // We could allow wide raw pointers where both sides are integers in the future,
             // but for now we reject them.
-            if matches!(val.layout.abi, Abi::ScalarPair(..)) {
+            if matches!(val.layout.backend_repr, BackendRepr::ScalarPair(..)) {
                 return Err(ValTreeCreationError::NonSupportedType(ty));
             }
             let val = val.to_scalar();
@@ -311,7 +311,7 @@ pub fn valtree_to_const_value<'tcx>(
                 // Fast path to avoid some allocations.
                 return mir::ConstValue::ZeroSized;
             }
-            if layout.abi.is_scalar()
+            if layout.backend_repr.is_scalar()
                 && (matches!(ty.kind(), ty::Tuple(_))
                     || matches!(ty.kind(), ty::Adt(def, _) if def.is_struct()))
             {
diff --git a/compiler/rustc_const_eval/src/interpret/call.rs b/compiler/rustc_const_eval/src/interpret/call.rs
index 85d99900c6ccd..1915bf75c95ad 100644
--- a/compiler/rustc_const_eval/src/interpret/call.rs
+++ b/compiler/rustc_const_eval/src/interpret/call.rs
@@ -172,8 +172,8 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         // must be compatible. So we just accept everything with Pointer ABI as compatible,
         // even if this will accept some code that is not stably guaranteed to work.
         // This also handles function pointers.
-        let thin_pointer = |layout: TyAndLayout<'tcx>| match layout.abi {
-            abi::Abi::Scalar(s) => match s.primitive() {
+        let thin_pointer = |layout: TyAndLayout<'tcx>| match layout.backend_repr {
+            abi::BackendRepr::Scalar(s) => match s.primitive() {
                 abi::Primitive::Pointer(addr_space) => Some(addr_space),
                 _ => None,
             },
diff --git a/compiler/rustc_const_eval/src/interpret/cast.rs b/compiler/rustc_const_eval/src/interpret/cast.rs
index 64b15611316f9..60d5e904bd9ab 100644
--- a/compiler/rustc_const_eval/src/interpret/cast.rs
+++ b/compiler/rustc_const_eval/src/interpret/cast.rs
@@ -274,7 +274,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         cast_ty: Ty<'tcx>,
     ) -> InterpResult<'tcx, Scalar<M::Provenance>> {
         // Let's make sure v is sign-extended *if* it has a signed type.
-        let signed = src_layout.abi.is_signed(); // Also asserts that abi is `Scalar`.
+        let signed = src_layout.backend_repr.is_signed(); // Also asserts that abi is `Scalar`.
 
         let v = match src_layout.ty.kind() {
             Uint(_) | RawPtr(..) | FnPtr(..) => scalar.to_uint(src_layout.size)?,
diff --git a/compiler/rustc_const_eval/src/interpret/discriminant.rs b/compiler/rustc_const_eval/src/interpret/discriminant.rs
index feed08606799b..bb4ac9556ea88 100644
--- a/compiler/rustc_const_eval/src/interpret/discriminant.rs
+++ b/compiler/rustc_const_eval/src/interpret/discriminant.rs
@@ -112,7 +112,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         // Read tag and sanity-check `tag_layout`.
         let tag_val = self.read_immediate(&self.project_field(op, tag_field)?)?;
         assert_eq!(tag_layout.size, tag_val.layout.size);
-        assert_eq!(tag_layout.abi.is_signed(), tag_val.layout.abi.is_signed());
+        assert_eq!(tag_layout.backend_repr.is_signed(), tag_val.layout.backend_repr.is_signed());
         trace!("tag value: {}", tag_val);
 
         // Figure out which discriminant and variant this corresponds to.
diff --git a/compiler/rustc_const_eval/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs
index a1c773a4b8005..d81368e9fcc39 100644
--- a/compiler/rustc_const_eval/src/interpret/eval_context.rs
+++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs
@@ -9,7 +9,9 @@ use rustc_middle::query::TyCtxtAt;
 use rustc_middle::ty::layout::{
     self, FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, TyAndLayout,
 };
-use rustc_middle::ty::{self, GenericArgsRef, ParamEnv, Ty, TyCtxt, TypeFoldable, Variance};
+use rustc_middle::ty::{
+    self, GenericArgsRef, ParamEnv, Ty, TyCtxt, TypeFoldable, TypingMode, Variance,
+};
 use rustc_middle::{mir, span_bug};
 use rustc_session::Limit;
 use rustc_span::Span;
@@ -325,7 +327,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             return true;
         }
         // Slow path: spin up an inference context to check if these traits are sufficiently equal.
-        let infcx = self.tcx.infer_ctxt().build();
+        let infcx = self.tcx.infer_ctxt().build(TypingMode::from_param_env(self.param_env));
         let ocx = ObligationCtxt::new(&infcx);
         let cause = ObligationCause::dummy_with_span(self.cur_span());
         // equate the two trait refs after normalization
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index 6148123bdfeb4..80e14ee887cb1 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -563,7 +563,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             self.binary_op(mir_op.wrapping_to_overflowing().unwrap(), l, r)?.to_scalar_pair();
         interp_ok(if overflowed.to_bool()? {
             let size = l.layout.size;
-            if l.layout.abi.is_signed() {
+            if l.layout.backend_repr.is_signed() {
                 // For signed ints the saturated value depends on the sign of the first
                 // term since the sign of the second term can be inferred from this and
                 // the fact that the operation has overflowed (if either is 0 no
diff --git a/compiler/rustc_const_eval/src/interpret/operand.rs b/compiler/rustc_const_eval/src/interpret/operand.rs
index cd5e2aeca855e..43ae98e74b002 100644
--- a/compiler/rustc_const_eval/src/interpret/operand.rs
+++ b/compiler/rustc_const_eval/src/interpret/operand.rs
@@ -5,7 +5,7 @@ use std::assert_matches::assert_matches;
 
 use either::{Either, Left, Right};
 use rustc_abi as abi;
-use rustc_abi::{Abi, HasDataLayout, Size};
+use rustc_abi::{BackendRepr, HasDataLayout, Size};
 use rustc_hir::def::Namespace;
 use rustc_middle::mir::interpret::ScalarSizeMismatch;
 use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutOf, TyAndLayout};
@@ -114,9 +114,9 @@ impl<Prov: Provenance> Immediate<Prov> {
     }
 
     /// Assert that this immediate is a valid value for the given ABI.
-    pub fn assert_matches_abi(self, abi: Abi, msg: &str, cx: &impl HasDataLayout) {
+    pub fn assert_matches_abi(self, abi: BackendRepr, msg: &str, cx: &impl HasDataLayout) {
         match (self, abi) {
-            (Immediate::Scalar(scalar), Abi::Scalar(s)) => {
+            (Immediate::Scalar(scalar), BackendRepr::Scalar(s)) => {
                 assert_eq!(scalar.size(), s.size(cx), "{msg}: scalar value has wrong size");
                 if !matches!(s.primitive(), abi::Primitive::Pointer(..)) {
                     // This is not a pointer, it should not carry provenance.
@@ -126,7 +126,7 @@ impl<Prov: Provenance> Immediate<Prov> {
                     );
                 }
             }
-            (Immediate::ScalarPair(a_val, b_val), Abi::ScalarPair(a, b)) => {
+            (Immediate::ScalarPair(a_val, b_val), BackendRepr::ScalarPair(a, b)) => {
                 assert_eq!(
                     a_val.size(),
                     a.size(cx),
@@ -244,7 +244,7 @@ impl<'tcx, Prov: Provenance> std::ops::Deref for ImmTy<'tcx, Prov> {
 impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
     #[inline]
     pub fn from_scalar(val: Scalar<Prov>, layout: TyAndLayout<'tcx>) -> Self {
-        debug_assert!(layout.abi.is_scalar(), "`ImmTy::from_scalar` on non-scalar layout");
+        debug_assert!(layout.backend_repr.is_scalar(), "`ImmTy::from_scalar` on non-scalar layout");
         debug_assert_eq!(val.size(), layout.size);
         ImmTy { imm: val.into(), layout }
     }
@@ -252,7 +252,7 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
     #[inline]
     pub fn from_scalar_pair(a: Scalar<Prov>, b: Scalar<Prov>, layout: TyAndLayout<'tcx>) -> Self {
         debug_assert!(
-            matches!(layout.abi, Abi::ScalarPair(..)),
+            matches!(layout.backend_repr, BackendRepr::ScalarPair(..)),
             "`ImmTy::from_scalar_pair` on non-scalar-pair layout"
         );
         let imm = Immediate::ScalarPair(a, b);
@@ -263,9 +263,9 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
     pub fn from_immediate(imm: Immediate<Prov>, layout: TyAndLayout<'tcx>) -> Self {
         // Without a `cx` we cannot call `assert_matches_abi`.
         debug_assert!(
-            match (imm, layout.abi) {
-                (Immediate::Scalar(..), Abi::Scalar(..)) => true,
-                (Immediate::ScalarPair(..), Abi::ScalarPair(..)) => true,
+            match (imm, layout.backend_repr) {
+                (Immediate::Scalar(..), BackendRepr::Scalar(..)) => true,
+                (Immediate::ScalarPair(..), BackendRepr::ScalarPair(..)) => true,
                 (Immediate::Uninit, _) if layout.is_sized() => true,
                 _ => false,
             },
@@ -356,7 +356,11 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
     fn offset_(&self, offset: Size, layout: TyAndLayout<'tcx>, cx: &impl HasDataLayout) -> Self {
         // Verify that the input matches its type.
         if cfg!(debug_assertions) {
-            self.assert_matches_abi(self.layout.abi, "invalid input to Immediate::offset", cx);
+            self.assert_matches_abi(
+                self.layout.backend_repr,
+                "invalid input to Immediate::offset",
+                cx,
+            );
         }
         // `ImmTy` have already been checked to be in-bounds, so we can just check directly if this
         // remains in-bounds. This cannot actually be violated since projections are type-checked
@@ -370,19 +374,19 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
         );
         // This makes several assumptions about what layouts we will encounter; we match what
         // codegen does as good as we can (see `extract_field` in `rustc_codegen_ssa/src/mir/operand.rs`).
-        let inner_val: Immediate<_> = match (**self, self.layout.abi) {
+        let inner_val: Immediate<_> = match (**self, self.layout.backend_repr) {
             // If the entire value is uninit, then so is the field (can happen in ConstProp).
             (Immediate::Uninit, _) => Immediate::Uninit,
             // If the field is uninhabited, we can forget the data (can happen in ConstProp).
             // `enum S { A(!), B, C }` is an example of an enum with Scalar layout that
             // has an `Uninhabited` variant, which means this case is possible.
-            _ if layout.abi.is_uninhabited() => Immediate::Uninit,
+            _ if layout.is_uninhabited() => Immediate::Uninit,
             // the field contains no information, can be left uninit
             // (Scalar/ScalarPair can contain even aligned ZST, not just 1-ZST)
             _ if layout.is_zst() => Immediate::Uninit,
             // some fieldless enum variants can have non-zero size but still `Aggregate` ABI... try
             // to detect those here and also give them no data
-            _ if matches!(layout.abi, Abi::Aggregate { .. })
+            _ if matches!(layout.backend_repr, BackendRepr::Memory { .. })
                 && matches!(layout.variants, abi::Variants::Single { .. })
                 && matches!(&layout.fields, abi::FieldsShape::Arbitrary { offsets, .. } if offsets.len() == 0) =>
             {
@@ -394,7 +398,7 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
                 **self
             }
             // extract fields from types with `ScalarPair` ABI
-            (Immediate::ScalarPair(a_val, b_val), Abi::ScalarPair(a, b)) => {
+            (Immediate::ScalarPair(a_val, b_val), BackendRepr::ScalarPair(a, b)) => {
                 Immediate::from(if offset.bytes() == 0 {
                     a_val
                 } else {
@@ -411,7 +415,11 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
             ),
         };
         // Ensure the new layout matches the new value.
-        inner_val.assert_matches_abi(layout.abi, "invalid field type in Immediate::offset", cx);
+        inner_val.assert_matches_abi(
+            layout.backend_repr,
+            "invalid field type in Immediate::offset",
+            cx,
+        );
 
         ImmTy::from_immediate(inner_val, layout)
     }
@@ -567,8 +575,8 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         // case where some of the bytes are initialized and others are not. So, we need an extra
         // check that walks over the type of `mplace` to make sure it is truly correct to treat this
         // like a `Scalar` (or `ScalarPair`).
-        interp_ok(match mplace.layout.abi {
-            Abi::Scalar(abi::Scalar::Initialized { value: s, .. }) => {
+        interp_ok(match mplace.layout.backend_repr {
+            BackendRepr::Scalar(abi::Scalar::Initialized { value: s, .. }) => {
                 let size = s.size(self);
                 assert_eq!(size, mplace.layout.size, "abi::Scalar size does not match layout size");
                 let scalar = alloc.read_scalar(
@@ -577,7 +585,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 )?;
                 Some(ImmTy::from_scalar(scalar, mplace.layout))
             }
-            Abi::ScalarPair(
+            BackendRepr::ScalarPair(
                 abi::Scalar::Initialized { value: a, .. },
                 abi::Scalar::Initialized { value: b, .. },
             ) => {
@@ -637,9 +645,12 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         op: &impl Projectable<'tcx, M::Provenance>,
     ) -> InterpResult<'tcx, ImmTy<'tcx, M::Provenance>> {
         if !matches!(
-            op.layout().abi,
-            Abi::Scalar(abi::Scalar::Initialized { .. })
-                | Abi::ScalarPair(abi::Scalar::Initialized { .. }, abi::Scalar::Initialized { .. })
+            op.layout().backend_repr,
+            BackendRepr::Scalar(abi::Scalar::Initialized { .. })
+                | BackendRepr::ScalarPair(
+                    abi::Scalar::Initialized { .. },
+                    abi::Scalar::Initialized { .. }
+                )
         ) {
             span_bug!(self.cur_span(), "primitive read not possible for type: {}", op.layout().ty);
         }
diff --git a/compiler/rustc_const_eval/src/interpret/operator.rs b/compiler/rustc_const_eval/src/interpret/operator.rs
index 380db90748128..cf280e0c1aeb7 100644
--- a/compiler/rustc_const_eval/src/interpret/operator.rs
+++ b/compiler/rustc_const_eval/src/interpret/operator.rs
@@ -114,7 +114,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             let l_bits = left.layout.size.bits();
             // Compute the equivalent shift modulo `size` that is in the range `0..size`. (This is
             // the one MIR operator that does *not* directly map to a single LLVM operation.)
-            let (shift_amount, overflow) = if right.layout.abi.is_signed() {
+            let (shift_amount, overflow) = if right.layout.backend_repr.is_signed() {
                 let shift_amount = r_signed();
                 let rem = shift_amount.rem_euclid(l_bits.into());
                 // `rem` is guaranteed positive, so the `unwrap` cannot fail
@@ -126,7 +126,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             };
             let shift_amount = u32::try_from(shift_amount).unwrap(); // we brought this in the range `0..size` so this will always fit
             // Compute the shifted result.
-            let result = if left.layout.abi.is_signed() {
+            let result = if left.layout.backend_repr.is_signed() {
                 let l = l_signed();
                 let result = match bin_op {
                     Shl | ShlUnchecked => l.checked_shl(shift_amount).unwrap(),
@@ -147,7 +147,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             if overflow && let Some(intrinsic) = throw_ub_on_overflow {
                 throw_ub!(ShiftOverflow {
                     intrinsic,
-                    shift_amount: if right.layout.abi.is_signed() {
+                    shift_amount: if right.layout.backend_repr.is_signed() {
                         Either::Right(r_signed())
                     } else {
                         Either::Left(r_unsigned())
@@ -171,7 +171,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         let size = left.layout.size;
 
         // Operations that need special treatment for signed integers
-        if left.layout.abi.is_signed() {
+        if left.layout.backend_repr.is_signed() {
             let op: Option<fn(&i128, &i128) -> bool> = match bin_op {
                 Lt => Some(i128::lt),
                 Le => Some(i128::le),
@@ -250,7 +250,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             BitXor => ImmTy::from_uint(l ^ r, left.layout),
 
             _ => {
-                assert!(!left.layout.abi.is_signed());
+                assert!(!left.layout.backend_repr.is_signed());
                 let op: fn(u128, u128) -> (u128, bool) = match bin_op {
                     Add | AddUnchecked | AddWithOverflow => u128::overflowing_add,
                     Sub | SubUnchecked | SubWithOverflow => u128::overflowing_sub,
@@ -332,7 +332,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 }
 
                 let offset_bytes = val.to_target_isize(self)?;
-                if !right.layout.abi.is_signed() && offset_bytes < 0 {
+                if !right.layout.backend_repr.is_signed() && offset_bytes < 0 {
                     // We were supposed to do an unsigned offset but the result is negative -- this
                     // can only mean that the cast wrapped around.
                     throw_ub!(PointerArithOverflow)
diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs
index 81b926a1b65fa..139a1db60e03f 100644
--- a/compiler/rustc_const_eval/src/interpret/place.rs
+++ b/compiler/rustc_const_eval/src/interpret/place.rs
@@ -5,11 +5,11 @@
 use std::assert_matches::assert_matches;
 
 use either::{Either, Left, Right};
+use rustc_abi::{Align, BackendRepr, HasDataLayout, Size};
 use rustc_ast::Mutability;
 use rustc_middle::ty::Ty;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
 use rustc_middle::{bug, mir, span_bug};
-use rustc_target::abi::{Abi, Align, HasDataLayout, Size};
 use tracing::{instrument, trace};
 
 use super::{
@@ -659,7 +659,7 @@ where
                 // Unfortunately this is too expensive to do in release builds.
                 if cfg!(debug_assertions) {
                     src.assert_matches_abi(
-                        local_layout.abi,
+                        local_layout.backend_repr,
                         "invalid immediate for given destination place",
                         self,
                     );
@@ -683,7 +683,11 @@ where
     ) -> InterpResult<'tcx> {
         // We use the sizes from `value` below.
         // Ensure that matches the type of the place it is written to.
-        value.assert_matches_abi(layout.abi, "invalid immediate for given destination place", self);
+        value.assert_matches_abi(
+            layout.backend_repr,
+            "invalid immediate for given destination place",
+            self,
+        );
         // Note that it is really important that the type here is the right one, and matches the
         // type things are read at. In case `value` is a `ScalarPair`, we don't do any magic here
         // to handle padding properly, which is only correct if we never look at this data with the
@@ -700,7 +704,7 @@ where
                 alloc.write_scalar(alloc_range(Size::ZERO, scalar.size()), scalar)
             }
             Immediate::ScalarPair(a_val, b_val) => {
-                let Abi::ScalarPair(a, b) = layout.abi else {
+                let BackendRepr::ScalarPair(a, b) = layout.backend_repr else {
                     span_bug!(
                         self.cur_span(),
                         "write_immediate_to_mplace: invalid ScalarPair layout: {:#?}",
diff --git a/compiler/rustc_const_eval/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs
index 8b5bb1332e796..cd2c1ef36132e 100644
--- a/compiler/rustc_const_eval/src/interpret/validity.rs
+++ b/compiler/rustc_const_eval/src/interpret/validity.rs
@@ -11,6 +11,10 @@ use std::num::NonZero;
 
 use either::{Left, Right};
 use hir::def::DefKind;
+use rustc_abi::{
+    BackendRepr, FieldIdx, FieldsShape, Scalar as ScalarAbi, Size, VariantIdx, Variants,
+    WrappingRange,
+};
 use rustc_ast::Mutability;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
@@ -23,9 +27,6 @@ use rustc_middle::mir::interpret::{
 use rustc_middle::ty::layout::{LayoutCx, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{self, Ty};
 use rustc_span::symbol::{Symbol, sym};
-use rustc_target::abi::{
-    Abi, FieldIdx, FieldsShape, Scalar as ScalarAbi, Size, VariantIdx, Variants, WrappingRange,
-};
 use tracing::trace;
 
 use super::machine::AllocMap;
@@ -422,7 +423,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> {
         // Reset provenance: ensure slice tail metadata does not preserve provenance,
         // and ensure all pointers do not preserve partial provenance.
         if self.reset_provenance_and_padding {
-            if matches!(imm.layout.abi, Abi::Scalar(..)) {
+            if matches!(imm.layout.backend_repr, BackendRepr::Scalar(..)) {
                 // A thin pointer. If it has provenance, we don't have to do anything.
                 // If it does not, ensure we clear the provenance in memory.
                 if matches!(imm.to_scalar(), Scalar::Int(..)) {
@@ -981,7 +982,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> {
                     let elem = layout.field(cx, 0);
 
                     // Fast-path for large arrays of simple types that do not contain any padding.
-                    if elem.abi.is_scalar() {
+                    if elem.backend_repr.is_scalar() {
                         out.add_range(base_offset, elem.size * count);
                     } else {
                         for idx in 0..count {
@@ -1299,19 +1300,19 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValueVisitor<'tcx, M> for ValidityVisitor<'rt,
         // FIXME: We could avoid some redundant checks here. For newtypes wrapping
         // scalars, we do the same check on every "level" (e.g., first we check
         // MyNewtype and then the scalar in there).
-        match val.layout.abi {
-            Abi::Uninhabited => {
+        match val.layout.backend_repr {
+            BackendRepr::Uninhabited => {
                 let ty = val.layout.ty;
                 throw_validation_failure!(self.path, UninhabitedVal { ty });
             }
-            Abi::Scalar(scalar_layout) => {
+            BackendRepr::Scalar(scalar_layout) => {
                 if !scalar_layout.is_uninit_valid() {
                     // There is something to check here.
                     let scalar = self.read_scalar(val, ExpectedKind::InitScalar)?;
                     self.visit_scalar(scalar, scalar_layout)?;
                 }
             }
-            Abi::ScalarPair(a_layout, b_layout) => {
+            BackendRepr::ScalarPair(a_layout, b_layout) => {
                 // We can only proceed if *both* scalars need to be initialized.
                 // FIXME: find a way to also check ScalarPair when one side can be uninit but
                 // the other must be init.
@@ -1322,12 +1323,12 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValueVisitor<'tcx, M> for ValidityVisitor<'rt,
                     self.visit_scalar(b, b_layout)?;
                 }
             }
-            Abi::Vector { .. } => {
+            BackendRepr::Vector { .. } => {
                 // No checks here, we assume layout computation gets this right.
                 // (This is harder to check since Miri does not represent these as `Immediate`. We
                 // also cannot use field projections since this might be a newtype around a vector.)
             }
-            Abi::Aggregate { .. } => {
+            BackendRepr::Memory { .. } => {
                 // Nothing to do.
             }
         }
diff --git a/compiler/rustc_const_eval/src/util/check_validity_requirement.rs b/compiler/rustc_const_eval/src/util/check_validity_requirement.rs
index 7a8b976dfc4ee..f743525f35997 100644
--- a/compiler/rustc_const_eval/src/util/check_validity_requirement.rs
+++ b/compiler/rustc_const_eval/src/util/check_validity_requirement.rs
@@ -1,9 +1,9 @@
+use rustc_abi::{BackendRepr, FieldsShape, Scalar, Variants};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{
     HasTyCtxt, LayoutCx, LayoutError, LayoutOf, TyAndLayout, ValidityRequirement,
 };
 use rustc_middle::ty::{ParamEnvAnd, Ty, TyCtxt};
-use rustc_target::abi::{Abi, FieldsShape, Scalar, Variants};
 
 use crate::const_eval::{CanAccessMutGlobal, CheckAlignment, CompileTimeMachine};
 use crate::interpret::{InterpCx, MemoryKind};
@@ -111,12 +111,12 @@ fn check_validity_requirement_lax<'tcx>(
     };
 
     // Check the ABI.
-    let valid = match this.abi {
-        Abi::Uninhabited => false, // definitely UB
-        Abi::Scalar(s) => scalar_allows_raw_init(s),
-        Abi::ScalarPair(s1, s2) => scalar_allows_raw_init(s1) && scalar_allows_raw_init(s2),
-        Abi::Vector { element: s, count } => count == 0 || scalar_allows_raw_init(s),
-        Abi::Aggregate { .. } => true, // Fields are checked below.
+    let valid = match this.backend_repr {
+        BackendRepr::Uninhabited => false, // definitely UB
+        BackendRepr::Scalar(s) => scalar_allows_raw_init(s),
+        BackendRepr::ScalarPair(s1, s2) => scalar_allows_raw_init(s1) && scalar_allows_raw_init(s2),
+        BackendRepr::Vector { element: s, count } => count == 0 || scalar_allows_raw_init(s),
+        BackendRepr::Memory { .. } => true, // Fields are checked below.
     };
     if !valid {
         // This is definitely not okay.
diff --git a/compiler/rustc_const_eval/src/util/compare_types.rs b/compiler/rustc_const_eval/src/util/compare_types.rs
index 3ea54146fc787..7af977bab4d66 100644
--- a/compiler/rustc_const_eval/src/util/compare_types.rs
+++ b/compiler/rustc_const_eval/src/util/compare_types.rs
@@ -5,7 +5,7 @@
 
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::traits::ObligationCause;
-use rustc_middle::ty::{ParamEnv, Ty, TyCtxt, Variance};
+use rustc_middle::ty::{ParamEnv, Ty, TyCtxt, TypingMode, Variance};
 use rustc_trait_selection::traits::ObligationCtxt;
 
 /// Returns whether the two types are equal up to subtyping.
@@ -45,7 +45,8 @@ pub fn relate_types<'tcx>(
     }
 
     let mut builder = tcx.infer_ctxt().ignoring_regions();
-    let infcx = builder.build();
+    // FIXME(#132279): This should eventually use the already defined hidden types.
+    let infcx = builder.build(TypingMode::from_param_env(param_env));
     let ocx = ObligationCtxt::new(&infcx);
     let cause = ObligationCause::dummy();
     let src = ocx.normalize(&cause, param_env, src);
diff --git a/compiler/rustc_expand/messages.ftl b/compiler/rustc_expand/messages.ftl
index fcf3352bfc597..f26c7c1ba0bc4 100644
--- a/compiler/rustc_expand/messages.ftl
+++ b/compiler/rustc_expand/messages.ftl
@@ -74,7 +74,7 @@ expand_helper_attribute_name_invalid =
     `{$name}` cannot be a name of derive helper attribute
 
 expand_incomplete_parse =
-    macro expansion ignores token `{$token}` and any following
+    macro expansion ignores {$descr} and any tokens following
     .label = caused by the macro expansion here
     .note = the usage of `{$macro_path}!` is likely invalid in {$kind_name} context
     .suggestion_add_semi = you might be missing a semicolon here
diff --git a/compiler/rustc_expand/src/errors.rs b/compiler/rustc_expand/src/errors.rs
index 5682c574552b4..7bd7c30553913 100644
--- a/compiler/rustc_expand/src/errors.rs
+++ b/compiler/rustc_expand/src/errors.rs
@@ -275,7 +275,7 @@ pub(crate) struct UnsupportedKeyValue {
 pub(crate) struct IncompleteParse<'a> {
     #[primary_span]
     pub span: Span,
-    pub token: Cow<'a, str>,
+    pub descr: String,
     #[label]
     pub label_span: Span,
     pub macro_path: &'a ast::Path,
diff --git a/compiler/rustc_expand/src/expand.rs b/compiler/rustc_expand/src/expand.rs
index 5ffafcaa54262..04ac7891023f5 100644
--- a/compiler/rustc_expand/src/expand.rs
+++ b/compiler/rustc_expand/src/expand.rs
@@ -21,6 +21,7 @@ use rustc_errors::PResult;
 use rustc_feature::Features;
 use rustc_parse::parser::{
     AttemptLocalParseRecovery, CommaRecoveryMode, ForceCollect, Parser, RecoverColon, RecoverComma,
+    token_descr,
 };
 use rustc_parse::validate_attr;
 use rustc_session::lint::BuiltinLintDiag;
@@ -1013,7 +1014,7 @@ pub(crate) fn ensure_complete_parse<'a>(
     span: Span,
 ) {
     if parser.token != token::Eof {
-        let token = pprust::token_to_string(&parser.token);
+        let descr = token_descr(&parser.token);
         // Avoid emitting backtrace info twice.
         let def_site_span = parser.token.span.with_ctxt(SyntaxContext::root());
 
@@ -1029,7 +1030,7 @@ pub(crate) fn ensure_complete_parse<'a>(
 
         parser.dcx().emit_err(IncompleteParse {
             span: def_site_span,
-            token,
+            descr,
             label_span: span,
             macro_path,
             kind_name,
diff --git a/compiler/rustc_expand/src/mbe/diagnostics.rs b/compiler/rustc_expand/src/mbe/diagnostics.rs
index 103bbb05e7ff3..ffcce1e52f67f 100644
--- a/compiler/rustc_expand/src/mbe/diagnostics.rs
+++ b/compiler/rustc_expand/src/mbe/diagnostics.rs
@@ -2,10 +2,9 @@ use std::borrow::Cow;
 
 use rustc_ast::token::{self, Token, TokenKind};
 use rustc_ast::tokenstream::TokenStream;
-use rustc_ast_pretty::pprust;
 use rustc_errors::{Applicability, Diag, DiagCtxtHandle, DiagMessage};
 use rustc_macros::Subdiagnostic;
-use rustc_parse::parser::{Parser, Recovery};
+use rustc_parse::parser::{Parser, Recovery, token_descr};
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::Ident;
@@ -336,17 +335,11 @@ pub(super) fn annotate_doc_comment(err: &mut Diag<'_>, sm: &SourceMap, span: Spa
 /// other tokens, this is "unexpected token...".
 pub(super) fn parse_failure_msg(tok: &Token, expected_token: Option<&Token>) -> Cow<'static, str> {
     if let Some(expected_token) = expected_token {
-        Cow::from(format!(
-            "expected `{}`, found `{}`",
-            pprust::token_to_string(expected_token),
-            pprust::token_to_string(tok),
-        ))
+        Cow::from(format!("expected {}, found {}", token_descr(expected_token), token_descr(tok)))
     } else {
         match tok.kind {
             token::Eof => Cow::from("unexpected end of macro invocation"),
-            _ => {
-                Cow::from(format!("no rules expected the token `{}`", pprust::token_to_string(tok)))
-            }
+            _ => Cow::from(format!("no rules expected {}", token_descr(tok))),
         }
     }
 }
diff --git a/compiler/rustc_expand/src/mbe/macro_parser.rs b/compiler/rustc_expand/src/mbe/macro_parser.rs
index a08db612bbedb..2a8dddc1e004f 100644
--- a/compiler/rustc_expand/src/mbe/macro_parser.rs
+++ b/compiler/rustc_expand/src/mbe/macro_parser.rs
@@ -78,11 +78,10 @@ use std::rc::Rc;
 pub(crate) use NamedMatch::*;
 pub(crate) use ParseResult::*;
 use rustc_ast::token::{self, DocComment, NonterminalKind, Token};
-use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::ErrorGuaranteed;
 use rustc_lint_defs::pluralize;
-use rustc_parse::parser::{ParseNtResult, Parser};
+use rustc_parse::parser::{ParseNtResult, Parser, token_descr};
 use rustc_span::Span;
 use rustc_span::symbol::{Ident, MacroRulesNormalizedIdent};
 
@@ -150,7 +149,7 @@ impl Display for MatcherLoc {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             MatcherLoc::Token { token } | MatcherLoc::SequenceSep { separator: token } => {
-                write!(f, "`{}`", pprust::token_to_string(token))
+                write!(f, "{}", token_descr(token))
             }
             MatcherLoc::MetaVarDecl { bind, kind, .. } => {
                 write!(f, "meta-variable `${bind}")?;
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
index 6d04bdf7e48ed..f830108a02f4f 100644
--- a/compiler/rustc_hir_analysis/src/check/check.rs
+++ b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -30,6 +30,7 @@ use rustc_trait_selection::traits;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_type_ir::fold::TypeFoldable;
 use tracing::{debug, instrument};
+use ty::TypingMode;
 use {rustc_attr as attr, rustc_hir as hir};
 
 use super::compare_impl_item::{check_type_bounds, compare_impl_method, compare_impl_ty};
@@ -276,7 +277,8 @@ fn check_opaque_meets_bounds<'tcx>(
     };
     let param_env = tcx.param_env(defining_use_anchor);
 
-    let infcx = tcx.infer_ctxt().with_opaque_type_inference(defining_use_anchor).build();
+    // FIXME(#132279): This should eventually use the already defined hidden types.
+    let infcx = tcx.infer_ctxt().build(TypingMode::analysis_in_body(tcx, defining_use_anchor));
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
     let args = match *origin {
@@ -1675,8 +1677,8 @@ pub(super) fn check_coroutine_obligations(
         // typeck writeback gives us predicates with their regions erased.
         // As borrowck already has checked lifetimes, we do not need to do it again.
         .ignoring_regions()
-        .with_opaque_type_inference(def_id)
-        .build();
+        // FIXME(#132279): This should eventually use the already defined hidden types.
+        .build(TypingMode::analysis_in_body(tcx, def_id));
 
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
     for (predicate, cause) in &typeck_results.coroutine_stalled_predicates {
diff --git a/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs b/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
index 9de96b7ba7760..db2c44fd29df4 100644
--- a/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
+++ b/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
@@ -17,7 +17,7 @@ use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::util::ExplicitSelf;
 use rustc_middle::ty::{
     self, GenericArgs, GenericParamDefKind, Ty, TyCtxt, TypeFoldable, TypeFolder,
-    TypeSuperFoldable, TypeVisitableExt, Upcast,
+    TypeSuperFoldable, TypeVisitableExt, TypingMode, Upcast,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::Span;
@@ -228,7 +228,7 @@ fn compare_method_predicate_entailment<'tcx>(
     let param_env = traits::normalize_param_env_or_error(tcx, param_env, normalize_cause);
     debug!(caller_bounds=?param_env.caller_bounds());
 
-    let infcx = &tcx.infer_ctxt().build();
+    let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(infcx);
 
     // Create obligations for each predicate declared by the impl
@@ -516,7 +516,7 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>(
         ObligationCause::misc(tcx.def_span(impl_m_def_id), impl_m_def_id),
     );
 
-    let infcx = &tcx.infer_ctxt().build();
+    let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(infcx);
 
     // Normalize the impl signature with fresh variables for lifetime inference.
@@ -1196,7 +1196,7 @@ fn compare_self_type<'tcx>(
         let self_arg_ty = tcx.fn_sig(method.def_id).instantiate_identity().input(0);
         let param_env = ty::ParamEnv::reveal_all();
 
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let self_arg_ty = tcx.liberate_late_bound_regions(method.def_id, self_arg_ty);
         let can_eq_self = |ty| infcx.can_eq(param_env, untransformed_self_ty, ty);
         match ExplicitSelf::determine(self_arg_ty, can_eq_self) {
@@ -1801,7 +1801,7 @@ fn compare_const_predicate_entailment<'tcx>(
         ObligationCause::misc(impl_ct_span, impl_ct_def_id),
     );
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
     let impl_ct_own_bounds = impl_ct_predicates.instantiate_own_identity();
@@ -1951,7 +1951,7 @@ fn compare_type_predicate_entailment<'tcx>(
     let param_env = traits::normalize_param_env_or_error(tcx, param_env, normalize_cause);
     debug!(caller_bounds=?param_env.caller_bounds());
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
     for (predicate, span) in impl_ty_own_bounds {
@@ -2036,7 +2036,7 @@ pub(super) fn check_type_bounds<'tcx>(
     let impl_ty_args = GenericArgs::identity_for_item(tcx, impl_ty.def_id);
     let rebased_args = impl_ty_args.rebase_onto(tcx, container_id, impl_trait_ref.args);
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
     // A synthetic impl Trait for RPITIT desugaring or assoc type for effects desugaring has no HIR,
diff --git a/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs b/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs
index 2d6b9813271e2..646c104f1f553 100644
--- a/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs
+++ b/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs
@@ -8,7 +8,7 @@ use rustc_middle::span_bug;
 use rustc_middle::traits::{ObligationCause, Reveal};
 use rustc_middle::ty::{
     self, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperVisitable, TypeVisitable,
-    TypeVisitableExt, TypeVisitor,
+    TypeVisitableExt, TypeVisitor, TypingMode,
 };
 use rustc_span::Span;
 use rustc_trait_selection::regions::InferCtxtRegionExt;
@@ -132,7 +132,7 @@ pub(super) fn check_refining_return_position_impl_trait_in_trait<'tcx>(
     let param_env = ty::ParamEnv::new(tcx.mk_clauses_from_iter(hybrid_preds), Reveal::UserFacing);
     let param_env = normalize_param_env_or_error(tcx, param_env, ObligationCause::dummy());
 
-    let ref infcx = tcx.infer_ctxt().build();
+    let ref infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new(infcx);
 
     // Normalize the bounds. This has two purposes:
diff --git a/compiler/rustc_hir_analysis/src/check/dropck.rs b/compiler/rustc_hir_analysis/src/check/dropck.rs
index 97a29b32c0158..1c9bbe627fb07 100644
--- a/compiler/rustc_hir_analysis/src/check/dropck.rs
+++ b/compiler/rustc_hir_analysis/src/check/dropck.rs
@@ -9,7 +9,7 @@ use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{RegionResolutionError, TyCtxtInferExt};
 use rustc_infer::traits::{ObligationCause, ObligationCauseCode};
 use rustc_middle::ty::util::CheckRegions;
-use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypingMode};
 use rustc_trait_selection::regions::InferCtxtRegionExt;
 use rustc_trait_selection::traits::{self, ObligationCtxt};
 
@@ -124,7 +124,7 @@ fn ensure_drop_predicates_are_implied_by_item_defn<'tcx>(
     adt_def_id: LocalDefId,
     adt_to_impl_args: GenericArgsRef<'tcx>,
 ) -> Result<(), ErrorGuaranteed> {
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
     let impl_span = tcx.def_span(drop_impl_def_id.to_def_id());
diff --git a/compiler/rustc_hir_analysis/src/check/entry.rs b/compiler/rustc_hir_analysis/src/check/entry.rs
index 7da2cd93d4e01..0beb1f98d56de 100644
--- a/compiler/rustc_hir_analysis/src/check/entry.rs
+++ b/compiler/rustc_hir_analysis/src/check/entry.rs
@@ -4,7 +4,7 @@ use rustc_hir as hir;
 use rustc_hir::Node;
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::span_bug;
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypingMode};
 use rustc_session::config::EntryFnType;
 use rustc_span::Span;
 use rustc_span::def_id::{CRATE_DEF_ID, DefId, LocalDefId};
@@ -128,7 +128,7 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) {
             tcx.dcx().emit_err(errors::MainFunctionReturnTypeGeneric { span: return_ty_span });
             return;
         };
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let cause = traits::ObligationCause::new(
             return_ty_span,
             main_diagnostics_def_id,
diff --git a/compiler/rustc_hir_analysis/src/check/mod.rs b/compiler/rustc_hir_analysis/src/check/mod.rs
index ec5a89ec9d914..e9eea36a0e66c 100644
--- a/compiler/rustc_hir_analysis/src/check/mod.rs
+++ b/compiler/rustc_hir_analysis/src/check/mod.rs
@@ -85,7 +85,7 @@ use rustc_infer::infer::{self, TyCtxtInferExt as _};
 use rustc_infer::traits::ObligationCause;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::{self, GenericArgs, GenericArgsRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArgs, GenericArgsRef, Ty, TyCtxt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_session::parse::feature_err;
 use rustc_span::def_id::CRATE_DEF_ID;
@@ -530,7 +530,7 @@ fn suggestion_signature<'tcx>(
             let ty = tcx.type_of(assoc.def_id).instantiate_identity();
             let val = tcx
                 .infer_ctxt()
-                .build()
+                .build(TypingMode::non_body_analysis())
                 .err_ctxt()
                 .ty_kind_suggestion(tcx.param_env(assoc.def_id), ty)
                 .unwrap_or_else(|| "value".to_string());
@@ -620,7 +620,7 @@ pub fn check_function_signature<'tcx>(
 
     let param_env = ty::ParamEnv::empty();
 
-    let infcx = &tcx.infer_ctxt().build();
+    let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(infcx);
 
     let actual_sig = tcx.fn_sig(fn_id).instantiate_identity();
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
index 499e42d31c97f..12ed7b89f68be 100644
--- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs
+++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -17,7 +17,7 @@ use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::trait_def::TraitSpecializationKind;
 use rustc_middle::ty::{
     self, AdtKind, GenericArgKind, GenericArgs, GenericParamDefKind, Ty, TyCtxt, TypeFoldable,
-    TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor, Upcast,
+    TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor, TypingMode, Upcast,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_session::parse::feature_err;
@@ -106,7 +106,7 @@ where
     F: for<'a> FnOnce(&WfCheckingCtxt<'a, 'tcx>) -> Result<(), ErrorGuaranteed>,
 {
     let param_env = tcx.param_env(body_def_id);
-    let infcx = &tcx.infer_ctxt().build();
+    let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(infcx);
 
     let mut wfcx = WfCheckingCtxt { ocx, span, body_def_id, param_env };
@@ -765,7 +765,7 @@ fn test_region_obligations<'tcx>(
     // Unfortunately, we have to use a new `InferCtxt` each call, because
     // region constraints get added and solved there and we need to test each
     // call individually.
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
 
     add_constraints(&infcx);
 
diff --git a/compiler/rustc_hir_analysis/src/coherence/builtin.rs b/compiler/rustc_hir_analysis/src/coherence/builtin.rs
index b4f6b5a9dd24f..5ff52376837eb 100644
--- a/compiler/rustc_hir_analysis/src/coherence/builtin.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/builtin.rs
@@ -15,7 +15,9 @@ use rustc_infer::infer::{self, RegionResolutionError, TyCtxtInferExt};
 use rustc_infer::traits::Obligation;
 use rustc_middle::ty::adjustment::CoerceUnsizedInfo;
 use rustc_middle::ty::print::PrintTraitRefExt as _;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, suggest_constraining_type_params};
+use rustc_middle::ty::{
+    self, Ty, TyCtxt, TypeVisitableExt, TypingMode, suggest_constraining_type_params,
+};
 use rustc_span::{DUMMY_SP, Span};
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::traits::misc::{
@@ -213,7 +215,7 @@ fn visit_implementation_of_dispatch_from_dyn(checker: &Checker<'_>) -> Result<()
 
     let param_env = tcx.param_env(impl_did);
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let cause = ObligationCause::misc(span, impl_did);
 
     // Later parts of the compiler rely on all DispatchFromDyn types to be ABI-compatible with raw
@@ -354,7 +356,7 @@ pub(crate) fn coerce_unsized_info<'tcx>(
 
     debug!("visit_implementation_of_coerce_unsized: {:?} -> {:?} (free)", source, target);
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let cause = ObligationCause::misc(span, impl_did);
     let check_mutbl = |mt_a: ty::TypeAndMut<'tcx>,
                        mt_b: ty::TypeAndMut<'tcx>,
diff --git a/compiler/rustc_hir_analysis/src/coherence/orphan.rs b/compiler/rustc_hir_analysis/src/coherence/orphan.rs
index 04770469132bb..8a1a887766c75 100644
--- a/compiler/rustc_hir_analysis/src/coherence/orphan.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/orphan.rs
@@ -7,7 +7,7 @@ use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
 use rustc_lint_defs::builtin::UNCOVERED_PARAM_IN_PROJECTION;
 use rustc_middle::ty::{
     self, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeSuperVisitable,
-    TypeVisitable, TypeVisitableExt, TypeVisitor,
+    TypeVisitable, TypeVisitableExt, TypeVisitor, TypingMode,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::def_id::{DefId, LocalDefId};
@@ -302,7 +302,7 @@ fn orphan_check<'tcx>(
     }
 
     // (1)  Instantiate all generic params with fresh inference vars.
-    let infcx = tcx.infer_ctxt().intercrate(true).build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::Coherence);
     let cause = traits::ObligationCause::dummy();
     let args = infcx.fresh_args_for_item(cause.span, impl_def_id.to_def_id());
     let trait_ref = trait_ref.instantiate(tcx, args);
diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs
index 3add801cf5649..cca52c5142c61 100644
--- a/compiler/rustc_hir_analysis/src/collect.rs
+++ b/compiler/rustc_hir_analysis/src/collect.rs
@@ -34,7 +34,7 @@ use rustc_infer::traits::ObligationCause;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::util::{Discr, IntTypeExt};
-use rustc_middle::ty::{self, AdtKind, Const, IsSuggestable, Ty, TyCtxt};
+use rustc_middle::ty::{self, AdtKind, Const, IsSuggestable, Ty, TyCtxt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_span::symbol::{Ident, Symbol, kw, sym};
 use rustc_span::{DUMMY_SP, Span};
@@ -1438,9 +1438,11 @@ fn infer_return_ty_for_fn_sig<'tcx>(
                     Applicability::MachineApplicable,
                 );
                 recovered_ret_ty = Some(suggestable_ret_ty);
-            } else if let Some(sugg) =
-                suggest_impl_trait(&tcx.infer_ctxt().build(), tcx.param_env(def_id), ret_ty)
-            {
+            } else if let Some(sugg) = suggest_impl_trait(
+                &tcx.infer_ctxt().build(TypingMode::non_body_analysis()),
+                tcx.param_env(def_id),
+                ret_ty,
+            ) {
                 diag.span_suggestion(
                     ty.span,
                     "replace with an appropriate return type",
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
index 0891642f2c88c..2d0c3ec28c372 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
@@ -39,7 +39,7 @@ use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
 use rustc_middle::ty::print::PrintPolyTraitRefExt as _;
 use rustc_middle::ty::{
     self, Const, GenericArgKind, GenericArgsRef, GenericParamDefKind, ParamEnv, Ty, TyCtxt,
-    TypeVisitableExt,
+    TypeVisitableExt, TypingMode,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint::builtin::AMBIGUOUS_ASSOCIATED_ITEMS;
@@ -1300,7 +1300,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             Some(infcx) => infcx,
             None => {
                 assert!(!self_ty.has_infer());
-                infcx_ = tcx.infer_ctxt().ignoring_regions().build();
+                infcx_ = tcx.infer_ctxt().ignoring_regions().build(TypingMode::non_body_analysis());
                 &infcx_
             }
         };
@@ -1492,7 +1492,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             infcx
         } else {
             assert!(!qself_ty.has_infer());
-            infcx_ = tcx.infer_ctxt().build();
+            infcx_ = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
             &infcx_
         };
 
diff --git a/compiler/rustc_hir_analysis/src/hir_wf_check.rs b/compiler/rustc_hir_analysis/src/hir_wf_check.rs
index 2fa4ca680737d..5b0165bf993da 100644
--- a/compiler/rustc_hir_analysis/src/hir_wf_check.rs
+++ b/compiler/rustc_hir_analysis/src/hir_wf_check.rs
@@ -5,7 +5,7 @@ use rustc_infer::infer::TyCtxtInferExt;
 use rustc_infer::traits::{ObligationCause, WellFormedLoc};
 use rustc_middle::bug;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::{self, TyCtxt};
+use rustc_middle::ty::{self, TyCtxt, TypingMode};
 use rustc_span::def_id::LocalDefId;
 use rustc_trait_selection::traits::{self, ObligationCtxt};
 use tracing::debug;
@@ -68,7 +68,7 @@ fn diagnostic_hir_wf_check<'tcx>(
 
     impl<'tcx> Visitor<'tcx> for HirWfCheck<'tcx> {
         fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) {
-            let infcx = self.tcx.infer_ctxt().build();
+            let infcx = self.tcx.infer_ctxt().build(TypingMode::non_body_analysis());
             let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
             let tcx_ty = self.icx.lower_ty(ty);
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
index a394fc2fbb199..b0c9aed5d8557 100644
--- a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
+++ b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
@@ -72,7 +72,9 @@ use rustc_infer::infer::TyCtxtInferExt;
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::traits::specialization_graph::Node;
 use rustc_middle::ty::trait_def::TraitSpecializationKind;
-use rustc_middle::ty::{self, GenericArg, GenericArgs, GenericArgsRef, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{
+    self, GenericArg, GenericArgs, GenericArgsRef, TyCtxt, TypeVisitableExt, TypingMode,
+};
 use rustc_span::{ErrorGuaranteed, Span};
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
@@ -195,7 +197,7 @@ fn get_impl_args(
     impl1_def_id: LocalDefId,
     impl2_node: Node,
 ) -> Result<(GenericArgsRef<'_>, GenericArgsRef<'_>), ErrorGuaranteed> {
-    let infcx = &tcx.infer_ctxt().build();
+    let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(infcx);
     let param_env = tcx.param_env(impl1_def_id);
     let impl1_span = tcx.def_span(impl1_def_id);
@@ -409,7 +411,7 @@ fn check_predicates<'tcx>(
 
     // Include the well-formed predicates of the type parameters of the impl.
     for arg in tcx.impl_trait_ref(impl1_def_id).unwrap().instantiate_identity().args {
-        let infcx = &tcx.infer_ctxt().build();
+        let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let obligations =
             wf::obligations(infcx, tcx.param_env(impl1_def_id), impl1_def_id, 0, arg, span)
                 .unwrap();
diff --git a/compiler/rustc_hir_typeck/src/typeck_root_ctxt.rs b/compiler/rustc_hir_typeck/src/typeck_root_ctxt.rs
index 18e40cfa42874..903be7e732afa 100644
--- a/compiler/rustc_hir_typeck/src/typeck_root_ctxt.rs
+++ b/compiler/rustc_hir_typeck/src/typeck_root_ctxt.rs
@@ -8,7 +8,7 @@ use rustc_hir::{HirId, HirIdMap};
 use rustc_infer::infer::{InferCtxt, InferOk, TyCtxtInferExt};
 use rustc_middle::span_bug;
 use rustc_middle::ty::visit::TypeVisitableExt;
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypingMode};
 use rustc_span::Span;
 use rustc_span::def_id::LocalDefIdMap;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
@@ -81,7 +81,8 @@ impl<'tcx> TypeckRootCtxt<'tcx> {
     pub(crate) fn new(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> Self {
         let hir_owner = tcx.local_def_id_to_hir_id(def_id).owner;
 
-        let infcx = tcx.infer_ctxt().ignoring_regions().with_opaque_type_inference(def_id).build();
+        let infcx =
+            tcx.infer_ctxt().ignoring_regions().build(TypingMode::analysis_in_body(tcx, def_id));
         let typeck_results = RefCell::new(ty::TypeckResults::new(hir_owner));
 
         TypeckRootCtxt {
diff --git a/compiler/rustc_infer/src/infer/at.rs b/compiler/rustc_infer/src/infer/at.rs
index 8c943a961e76a..3eda3e9c67e85 100644
--- a/compiler/rustc_infer/src/infer/at.rs
+++ b/compiler/rustc_infer/src/infer/at.rs
@@ -28,7 +28,7 @@
 use relate::lattice::{LatticeOp, LatticeOpKind};
 use rustc_middle::bug;
 use rustc_middle::ty::relate::solver_relating::RelateExt as NextSolverRelate;
-use rustc_middle::ty::{Const, ImplSubject};
+use rustc_middle::ty::{Const, ImplSubject, TypingMode};
 
 use super::*;
 use crate::infer::relate::type_relating::TypeRelating;
@@ -67,30 +67,48 @@ impl<'tcx> InferCtxt<'tcx> {
     /// variables in the same state. This can be used to "branch off" many tests from the same
     /// common state.
     pub fn fork(&self) -> Self {
-        self.fork_with_intercrate(self.intercrate)
+        Self {
+            tcx: self.tcx,
+            typing_mode: self.typing_mode,
+            considering_regions: self.considering_regions,
+            skip_leak_check: self.skip_leak_check,
+            inner: self.inner.clone(),
+            lexical_region_resolutions: self.lexical_region_resolutions.clone(),
+            selection_cache: self.selection_cache.clone(),
+            evaluation_cache: self.evaluation_cache.clone(),
+            reported_trait_errors: self.reported_trait_errors.clone(),
+            reported_signature_mismatch: self.reported_signature_mismatch.clone(),
+            tainted_by_errors: self.tainted_by_errors.clone(),
+            universe: self.universe.clone(),
+            next_trait_solver: self.next_trait_solver,
+            obligation_inspector: self.obligation_inspector.clone(),
+        }
     }
 
     /// Forks the inference context, creating a new inference context with the same inference
     /// variables in the same state, except possibly changing the intercrate mode. This can be
     /// used to "branch off" many tests from the same common state. Used in negative coherence.
-    pub fn fork_with_intercrate(&self, intercrate: bool) -> Self {
-        Self {
+    pub fn fork_with_typing_mode(&self, typing_mode: TypingMode<'tcx>) -> Self {
+        // Unlike `fork`, this invalidates all cache entries as they may depend on the
+        // typing mode.
+        let forked = Self {
             tcx: self.tcx,
-            defining_opaque_types: self.defining_opaque_types,
+            typing_mode,
             considering_regions: self.considering_regions,
             skip_leak_check: self.skip_leak_check,
             inner: self.inner.clone(),
             lexical_region_resolutions: self.lexical_region_resolutions.clone(),
-            selection_cache: self.selection_cache.clone(),
-            evaluation_cache: self.evaluation_cache.clone(),
+            selection_cache: Default::default(),
+            evaluation_cache: Default::default(),
             reported_trait_errors: self.reported_trait_errors.clone(),
             reported_signature_mismatch: self.reported_signature_mismatch.clone(),
             tainted_by_errors: self.tainted_by_errors.clone(),
             universe: self.universe.clone(),
-            intercrate,
             next_trait_solver: self.next_trait_solver,
             obligation_inspector: self.obligation_inspector.clone(),
-        }
+        };
+        forked.inner.borrow_mut().projection_cache().clear();
+        forked
     }
 }
 
diff --git a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
index 90d07964fdac0..c9d8ebecef050 100644
--- a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
+++ b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
@@ -46,7 +46,7 @@ impl<'tcx> InferCtxt<'tcx> {
         V: TypeFoldable<TyCtxt<'tcx>>,
     {
         let (param_env, value) = value.into_parts();
-        let param_env = self.tcx.canonical_param_env_cache.get_or_insert(
+        let canonical_param_env = self.tcx.canonical_param_env_cache.get_or_insert(
             self.tcx,
             param_env,
             query_state,
@@ -64,7 +64,7 @@ impl<'tcx> InferCtxt<'tcx> {
         );
 
         let canonical = Canonicalizer::canonicalize_with_base(
-            param_env,
+            canonical_param_env,
             value,
             Some(self),
             self.tcx,
@@ -72,7 +72,7 @@ impl<'tcx> InferCtxt<'tcx> {
             query_state,
         )
         .unchecked_map(|(param_env, value)| param_env.and(value));
-        CanonicalQueryInput { canonical, defining_opaque_types: self.defining_opaque_types() }
+        CanonicalQueryInput { canonical, typing_mode: self.typing_mode(param_env) }
     }
 
     /// Canonicalizes a query *response* `V`. When we canonicalize a
diff --git a/compiler/rustc_infer/src/infer/context.rs b/compiler/rustc_infer/src/infer/context.rs
index 0c151a11ad4e3..ecda9c6eb000a 100644
--- a/compiler/rustc_infer/src/infer/context.rs
+++ b/compiler/rustc_infer/src/infer/context.rs
@@ -1,7 +1,6 @@
 ///! Definition of `InferCtxtLike` from the librarified type layer.
-use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_hir::def_id::DefId;
 use rustc_middle::traits::ObligationCause;
-use rustc_middle::traits::solve::SolverMode;
 use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::relate::RelateResult;
 use rustc_middle::ty::relate::combine::PredicateEmittingRelation;
@@ -21,11 +20,11 @@ impl<'tcx> rustc_type_ir::InferCtxtLike for InferCtxt<'tcx> {
         self.next_trait_solver
     }
 
-    fn solver_mode(&self) -> ty::solve::SolverMode {
-        match self.intercrate {
-            true => SolverMode::Coherence,
-            false => SolverMode::Normal,
-        }
+    fn typing_mode(
+        &self,
+        param_env_for_debug_assertion: ty::ParamEnv<'tcx>,
+    ) -> ty::TypingMode<'tcx> {
+        self.typing_mode(param_env_for_debug_assertion)
     }
 
     fn universe(&self) -> ty::UniverseIndex {
@@ -91,10 +90,6 @@ impl<'tcx> rustc_type_ir::InferCtxtLike for InferCtxt<'tcx> {
         self.inner.borrow_mut().unwrap_region_constraints().opportunistic_resolve_var(self.tcx, vid)
     }
 
-    fn defining_opaque_types(&self) -> &'tcx ty::List<LocalDefId> {
-        self.defining_opaque_types()
-    }
-
     fn next_ty_infer(&self) -> Ty<'tcx> {
         self.next_ty_var(DUMMY_SP)
     }
diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs
index be43cba97f08f..fc54d69449f04 100644
--- a/compiler/rustc_infer/src/infer/mod.rs
+++ b/compiler/rustc_infer/src/infer/mod.rs
@@ -38,11 +38,12 @@ use rustc_middle::ty::fold::{
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
     self, ConstVid, FloatVid, GenericArg, GenericArgKind, GenericArgs, GenericArgsRef,
-    GenericParamDefKind, InferConst, IntVid, Ty, TyCtxt, TyVid,
+    GenericParamDefKind, InferConst, IntVid, Ty, TyCtxt, TyVid, TypingMode,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::Span;
 use rustc_span::symbol::Symbol;
+use rustc_type_ir::solve::Reveal;
 use snapshot::undo_log::InferCtxtUndoLogs;
 use tracing::{debug, instrument};
 use type_variable::TypeVariableOrigin;
@@ -243,8 +244,9 @@ impl<'tcx> InferCtxtInner<'tcx> {
 pub struct InferCtxt<'tcx> {
     pub tcx: TyCtxt<'tcx>,
 
-    /// The `DefIds` of the opaque types that may have their hidden types constrained.
-    defining_opaque_types: &'tcx ty::List<LocalDefId>,
+    /// The mode of this inference context, see the struct documentation
+    /// for more details.
+    typing_mode: TypingMode<'tcx>,
 
     /// Whether this inference context should care about region obligations in
     /// the root universe. Most notably, this is used during hir typeck as region
@@ -296,26 +298,6 @@ pub struct InferCtxt<'tcx> {
     /// bound.
     universe: Cell<ty::UniverseIndex>,
 
-    /// During coherence we have to assume that other crates may add
-    /// additional impls which we currently don't know about.
-    ///
-    /// To deal with this evaluation, we should be conservative
-    /// and consider the possibility of impls from outside this crate.
-    /// This comes up primarily when resolving ambiguity. Imagine
-    /// there is some trait reference `$0: Bar` where `$0` is an
-    /// inference variable. If `intercrate` is true, then we can never
-    /// say for sure that this reference is not implemented, even if
-    /// there are *no impls at all for `Bar`*, because `$0` could be
-    /// bound to some type that in a downstream crate that implements
-    /// `Bar`.
-    ///
-    /// Outside of coherence, we set this to false because we are only
-    /// interested in types that the user could actually have written.
-    /// In other words, we consider `$0: Bar` to be unimplemented if
-    /// there is no type that the user could *actually name* that
-    /// would satisfy it. This avoids crippling inference, basically.
-    pub intercrate: bool,
-
     next_trait_solver: bool,
 
     pub obligation_inspector: Cell<Option<ObligationInspector<'tcx>>>,
@@ -529,11 +511,8 @@ pub struct RegionObligation<'tcx> {
 /// Used to configure inference contexts before their creation.
 pub struct InferCtxtBuilder<'tcx> {
     tcx: TyCtxt<'tcx>,
-    defining_opaque_types: &'tcx ty::List<LocalDefId>,
     considering_regions: bool,
     skip_leak_check: bool,
-    /// Whether we are in coherence mode.
-    intercrate: bool,
     /// Whether we should use the new trait solver in the local inference context,
     /// which affects things like which solver is used in `predicate_may_hold`.
     next_trait_solver: bool,
@@ -544,37 +523,19 @@ impl<'tcx> TyCtxt<'tcx> {
     fn infer_ctxt(self) -> InferCtxtBuilder<'tcx> {
         InferCtxtBuilder {
             tcx: self,
-            defining_opaque_types: ty::List::empty(),
             considering_regions: true,
             skip_leak_check: false,
-            intercrate: false,
             next_trait_solver: self.next_trait_solver_globally(),
         }
     }
 }
 
 impl<'tcx> InferCtxtBuilder<'tcx> {
-    /// Whenever the `InferCtxt` should be able to handle defining uses of opaque types,
-    /// you need to call this function. Otherwise the opaque type will be treated opaquely.
-    ///
-    /// It is only meant to be called in two places, for typeck
-    /// (via `Inherited::build`) and for the inference context used
-    /// in mir borrowck.
-    pub fn with_opaque_type_inference(mut self, defining_anchor: LocalDefId) -> Self {
-        self.defining_opaque_types = self.tcx.opaque_types_defined_by(defining_anchor);
-        self
-    }
-
     pub fn with_next_trait_solver(mut self, next_trait_solver: bool) -> Self {
         self.next_trait_solver = next_trait_solver;
         self
     }
 
-    pub fn intercrate(mut self, intercrate: bool) -> Self {
-        self.intercrate = intercrate;
-        self
-    }
-
     pub fn ignoring_regions(mut self) -> Self {
         self.considering_regions = false;
         self
@@ -600,24 +561,17 @@ impl<'tcx> InferCtxtBuilder<'tcx> {
     where
         T: TypeFoldable<TyCtxt<'tcx>>,
     {
-        self.defining_opaque_types = input.defining_opaque_types;
-        let infcx = self.build();
+        let infcx = self.build(input.typing_mode);
         let (value, args) = infcx.instantiate_canonical(span, &input.canonical);
         (infcx, value, args)
     }
 
-    pub fn build(&mut self) -> InferCtxt<'tcx> {
-        let InferCtxtBuilder {
-            tcx,
-            defining_opaque_types,
-            considering_regions,
-            skip_leak_check,
-            intercrate,
-            next_trait_solver,
-        } = *self;
+    pub fn build(&mut self, typing_mode: TypingMode<'tcx>) -> InferCtxt<'tcx> {
+        let InferCtxtBuilder { tcx, considering_regions, skip_leak_check, next_trait_solver } =
+            *self;
         InferCtxt {
             tcx,
-            defining_opaque_types,
+            typing_mode,
             considering_regions,
             skip_leak_check,
             inner: RefCell::new(InferCtxtInner::new()),
@@ -628,7 +582,6 @@ impl<'tcx> InferCtxtBuilder<'tcx> {
             reported_signature_mismatch: Default::default(),
             tainted_by_errors: Cell::new(None),
             universe: Cell::new(ty::UniverseIndex::ROOT),
-            intercrate,
             next_trait_solver,
             obligation_inspector: Cell::new(None),
         }
@@ -659,14 +612,30 @@ impl<'tcx> InferCtxt<'tcx> {
         self.tcx.dcx().taintable_handle(&self.tainted_by_errors)
     }
 
-    pub fn defining_opaque_types(&self) -> &'tcx ty::List<LocalDefId> {
-        self.defining_opaque_types
-    }
-
     pub fn next_trait_solver(&self) -> bool {
         self.next_trait_solver
     }
 
+    #[inline(always)]
+    pub fn typing_mode(
+        &self,
+        param_env_for_debug_assertion: ty::ParamEnv<'tcx>,
+    ) -> TypingMode<'tcx> {
+        if cfg!(debug_assertions) {
+            match (param_env_for_debug_assertion.reveal(), self.typing_mode) {
+                (Reveal::All, TypingMode::PostAnalysis)
+                | (Reveal::UserFacing, TypingMode::Coherence | TypingMode::Analysis { .. }) => {}
+                (r, t) => unreachable!("TypingMode x Reveal mismatch: {r:?} {t:?}"),
+            }
+        }
+        self.typing_mode
+    }
+
+    #[inline(always)]
+    pub fn typing_mode_unchecked(&self) -> TypingMode<'tcx> {
+        self.typing_mode
+    }
+
     pub fn freshen<T: TypeFoldable<TyCtxt<'tcx>>>(&self, t: T) -> T {
         t.fold_with(&mut self.freshener())
     }
@@ -1029,8 +998,12 @@ impl<'tcx> InferCtxt<'tcx> {
 
     #[inline(always)]
     pub fn can_define_opaque_ty(&self, id: impl Into<DefId>) -> bool {
-        let Some(id) = id.into().as_local() else { return false };
-        self.defining_opaque_types.contains(&id)
+        match self.typing_mode_unchecked() {
+            TypingMode::Analysis { defining_opaque_types } => {
+                id.into().as_local().is_some_and(|def_id| defining_opaque_types.contains(&def_id))
+            }
+            TypingMode::Coherence | TypingMode::PostAnalysis => false,
+        }
     }
 
     pub fn ty_to_string(&self, t: Ty<'tcx>) -> String {
diff --git a/compiler/rustc_infer/src/infer/opaque_types/mod.rs b/compiler/rustc_infer/src/infer/opaque_types/mod.rs
index c38b7114e43eb..498d25aea640b 100644
--- a/compiler/rustc_infer/src/infer/opaque_types/mod.rs
+++ b/compiler/rustc_infer/src/infer/opaque_types/mod.rs
@@ -2,6 +2,7 @@ use hir::def_id::{DefId, LocalDefId};
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_data_structures::sync::Lrc;
 use rustc_hir as hir;
+use rustc_middle::bug;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::solve::Goal;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
@@ -100,7 +101,7 @@ impl<'tcx> InferCtxt<'tcx> {
         let process = |a: Ty<'tcx>, b: Ty<'tcx>| match *a.kind() {
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) if def_id.is_local() => {
                 let def_id = def_id.expect_local();
-                if self.intercrate {
+                if let ty::TypingMode::Coherence = self.typing_mode(param_env) {
                     // See comment on `insert_hidden_type` for why this is sufficient in coherence
                     return Some(self.register_hidden_type(
                         OpaqueTypeKey { def_id, args },
@@ -519,28 +520,32 @@ impl<'tcx> InferCtxt<'tcx> {
         // value being folded. In simple cases like `-> impl Foo`,
         // these are the same span, but not in cases like `-> (impl
         // Foo, impl Bar)`.
-        if self.intercrate {
-            // During intercrate we do not define opaque types but instead always
-            // force ambiguity unless the hidden type is known to not implement
-            // our trait.
-            goals.push(Goal::new(self.tcx, param_env, ty::PredicateKind::Ambiguous))
-        } else {
-            let prev = self
-                .inner
-                .borrow_mut()
-                .opaque_types()
-                .register(opaque_type_key, OpaqueHiddenType { ty: hidden_ty, span });
-            if let Some(prev) = prev {
-                goals.extend(
-                    self.at(&ObligationCause::dummy_with_span(span), param_env)
-                        .eq(DefineOpaqueTypes::Yes, prev, hidden_ty)?
-                        .obligations
-                        .into_iter()
-                        // FIXME: Shuttling between obligations and goals is awkward.
-                        .map(Goal::from),
-                );
+        match self.typing_mode(param_env) {
+            ty::TypingMode::Coherence => {
+                // During intercrate we do not define opaque types but instead always
+                // force ambiguity unless the hidden type is known to not implement
+                // our trait.
+                goals.push(Goal::new(self.tcx, param_env, ty::PredicateKind::Ambiguous));
             }
-        };
+            ty::TypingMode::Analysis { .. } => {
+                let prev = self
+                    .inner
+                    .borrow_mut()
+                    .opaque_types()
+                    .register(opaque_type_key, OpaqueHiddenType { ty: hidden_ty, span });
+                if let Some(prev) = prev {
+                    goals.extend(
+                        self.at(&ObligationCause::dummy_with_span(span), param_env)
+                            .eq(DefineOpaqueTypes::Yes, prev, hidden_ty)?
+                            .obligations
+                            .into_iter()
+                            // FIXME: Shuttling between obligations and goals is awkward.
+                            .map(Goal::from),
+                    );
+                }
+            }
+            ty::TypingMode::PostAnalysis => bug!("insert hidden type post-analysis"),
+        }
 
         Ok(())
     }
diff --git a/compiler/rustc_infer/src/infer/relate/generalize.rs b/compiler/rustc_infer/src/infer/relate/generalize.rs
index 32817dbcb2140..4c80bf4e07e8c 100644
--- a/compiler/rustc_infer/src/infer/relate/generalize.rs
+++ b/compiler/rustc_infer/src/infer/relate/generalize.rs
@@ -9,6 +9,7 @@ use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::visit::MaxUniverse;
 use rustc_middle::ty::{
     self, AliasRelationDirection, InferConst, Term, Ty, TyCtxt, TypeVisitable, TypeVisitableExt,
+    TypingMode,
 };
 use rustc_span::Span;
 use tracing::{debug, instrument, warn};
@@ -519,7 +520,10 @@ impl<'tcx> TypeRelation<TyCtxt<'tcx>> for Generalizer<'_, 'tcx> {
                             //
                             // cc trait-system-refactor-initiative#108
                             if self.infcx.next_trait_solver()
-                                && !self.infcx.intercrate
+                                && !matches!(
+                                    self.infcx.typing_mode_unchecked(),
+                                    TypingMode::Coherence
+                                )
                                 && self.in_alias
                             {
                                 inner.type_variables().equate(vid, new_var_id);
@@ -650,7 +654,10 @@ impl<'tcx> TypeRelation<TyCtxt<'tcx>> for Generalizer<'_, 'tcx> {
                             // See the comment for type inference variables
                             // for more details.
                             if self.infcx.next_trait_solver()
-                                && !self.infcx.intercrate
+                                && !matches!(
+                                    self.infcx.typing_mode_unchecked(),
+                                    TypingMode::Coherence
+                                )
                                 && self.in_alias
                             {
                                 variable_table.union(vid, new_var_id);
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index dbb8c66753236..02d22ee49bd60 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -16,6 +16,7 @@
 use std::fmt::Write;
 
 use ast::token::TokenKind;
+use rustc_abi::BackendRepr;
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_ast::visit::{FnCtxt, FnKind};
 use rustc_ast::{self as ast, *};
@@ -31,7 +32,7 @@ use rustc_middle::bug;
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::print::with_no_trimmed_paths;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, Upcast, VariantDef};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, TypingMode, Upcast, VariantDef};
 use rustc_session::lint::FutureIncompatibilityReason;
 // hardwired lints from rustc_lint_defs
 pub use rustc_session::lint::builtin::*;
@@ -40,7 +41,6 @@ use rustc_span::edition::Edition;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{Ident, Symbol, kw, sym};
 use rustc_span::{BytePos, InnerSpan, Span};
-use rustc_target::abi::Abi;
 use rustc_target::asm::InlineAsmArch;
 use rustc_trait_selection::infer::{InferCtxtExt, TyCtxtInferExt};
 use rustc_trait_selection::traits::misc::type_allowed_to_implement_copy;
@@ -604,7 +604,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations {
             && cx
                 .tcx
                 .infer_ctxt()
-                .build()
+                .build(cx.typing_mode())
                 .type_implements_trait(iter_trait, [ty], cx.param_env)
                 .must_apply_modulo_regions()
         {
@@ -648,7 +648,9 @@ fn type_implements_negative_copy_modulo_regions<'tcx>(
         predicate: pred.upcast(tcx),
     };
 
-    tcx.infer_ctxt().build().predicate_must_hold_modulo_regions(&obligation)
+    tcx.infer_ctxt()
+        .build(TypingMode::non_body_analysis())
+        .predicate_must_hold_modulo_regions(&obligation)
 }
 
 declare_lint! {
@@ -2466,7 +2468,9 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue {
 
             // Check if this ADT has a constrained layout (like `NonNull` and friends).
             if let Ok(layout) = cx.tcx.layout_of(cx.param_env.and(ty)) {
-                if let Abi::Scalar(scalar) | Abi::ScalarPair(scalar, _) = &layout.abi {
+                if let BackendRepr::Scalar(scalar) | BackendRepr::ScalarPair(scalar, _) =
+                    &layout.backend_repr
+                {
                     let range = scalar.valid_range(cx);
                     let msg = if !range.contains(0) {
                         "must be non-null"
diff --git a/compiler/rustc_lint/src/context.rs b/compiler/rustc_lint/src/context.rs
index 699088914e87e..aa7ec2659d089 100644
--- a/compiler/rustc_lint/src/context.rs
+++ b/compiler/rustc_lint/src/context.rs
@@ -14,11 +14,12 @@ use rustc_feature::Features;
 use rustc_hir::def::Res;
 use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
+use rustc_infer::traits::Reveal;
 use rustc_middle::bug;
 use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::ty::layout::{LayoutError, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::print::{PrintError, PrintTraitRefExt as _, Printer, with_no_trimmed_paths};
-use rustc_middle::ty::{self, GenericArg, RegisteredTools, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArg, RegisteredTools, Ty, TyCtxt, TypingMode};
 use rustc_session::lint::{
     BuiltinLintDiag, FutureIncompatibleInfo, Level, Lint, LintBuffer, LintExpectationId, LintId,
 };
@@ -698,6 +699,15 @@ impl LintContext for EarlyContext<'_> {
 }
 
 impl<'tcx> LateContext<'tcx> {
+    /// The typing mode of the currently visited node. Use this when
+    /// building a new `InferCtxt`.
+    pub fn typing_mode(&self) -> TypingMode<'tcx> {
+        debug_assert_eq!(self.param_env.reveal(), Reveal::UserFacing);
+        // FIXME(#132279): In case we're in a body, we should use a typing
+        // mode which reveals the opaque types defined by that body.
+        TypingMode::non_body_analysis()
+    }
+
     /// Gets the type-checking results for the current body,
     /// or `None` if outside a body.
     pub fn maybe_typeck_results(&self) -> Option<&'tcx ty::TypeckResults<'tcx>> {
diff --git a/compiler/rustc_lint/src/for_loops_over_fallibles.rs b/compiler/rustc_lint/src/for_loops_over_fallibles.rs
index fcb7a6108c0e2..cf68e41243ff3 100644
--- a/compiler/rustc_lint/src/for_loops_over_fallibles.rs
+++ b/compiler/rustc_lint/src/for_loops_over_fallibles.rs
@@ -166,7 +166,7 @@ fn suggest_question_mark<'tcx>(
     }
 
     let ty = args.type_at(0);
-    let infcx = cx.tcx.infer_ctxt().build();
+    let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
     let ocx = ObligationCtxt::new(&infcx);
 
     let body_def_id = cx.tcx.hir().body_owner_def_id(body_id);
diff --git a/compiler/rustc_lint/src/foreign_modules.rs b/compiler/rustc_lint/src/foreign_modules.rs
index abe4e3e78ee79..394ea798d3e53 100644
--- a/compiler/rustc_lint/src/foreign_modules.rs
+++ b/compiler/rustc_lint/src/foreign_modules.rs
@@ -217,7 +217,7 @@ fn structurally_same_type<'tcx>(
         // `extern` blocks cannot be generic, so we'll always get a layout here.
         let a_layout = tcx.layout_of(param_env.and(a)).unwrap();
         let b_layout = tcx.layout_of(param_env.and(b)).unwrap();
-        assert_eq!(a_layout.abi, b_layout.abi);
+        assert_eq!(a_layout.backend_repr, b_layout.backend_repr);
         assert_eq!(a_layout.size, b_layout.size);
         assert_eq!(a_layout.align, b_layout.align);
     }
diff --git a/compiler/rustc_lint/src/impl_trait_overcaptures.rs b/compiler/rustc_lint/src/impl_trait_overcaptures.rs
index cc40b67ab271d..026826021c813 100644
--- a/compiler/rustc_lint/src/impl_trait_overcaptures.rs
+++ b/compiler/rustc_lint/src/impl_trait_overcaptures.rs
@@ -15,7 +15,7 @@ use rustc_middle::ty::relate::{
     Relate, RelateResult, TypeRelation, structurally_relate_consts, structurally_relate_tys,
 };
 use rustc_middle::ty::{
-    self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor,
+    self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor, TypingMode,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint::FutureIncompatibilityReason;
@@ -184,7 +184,7 @@ fn check_fn(tcx: TyCtxt<'_>, parent_def_id: LocalDefId) {
         }),
         outlives_env: LazyCell::new(|| {
             let param_env = tcx.param_env(parent_def_id);
-            let infcx = tcx.infer_ctxt().build();
+            let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
             let ocx = ObligationCtxt::new(&infcx);
             let assumed_wf_tys = ocx.assumed_wf_types(param_env, parent_def_id).unwrap_or_default();
             let implied_bounds =
diff --git a/compiler/rustc_lint/src/non_fmt_panic.rs b/compiler/rustc_lint/src/non_fmt_panic.rs
index 51877e8a03495..cf25ec99e6713 100644
--- a/compiler/rustc_lint/src/non_fmt_panic.rs
+++ b/compiler/rustc_lint/src/non_fmt_panic.rs
@@ -157,7 +157,7 @@ fn check_panic<'tcx>(cx: &LateContext<'tcx>, f: &'tcx hir::Expr<'tcx>, arg: &'tc
                 Some(ty_def) if cx.tcx.is_lang_item(ty_def.did(), LangItem::String),
             );
 
-            let infcx = cx.tcx.infer_ctxt().build();
+            let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
             let suggest_display = is_str
                 || cx.tcx.get_diagnostic_item(sym::Display).is_some_and(|t| {
                     infcx.type_implements_trait(t, [ty], cx.param_env).may_apply()
diff --git a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
index ffbcf7f808ebe..16a1a5a72bc49 100644
--- a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
+++ b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
@@ -85,7 +85,7 @@ impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound {
         }
 
         let def_id = opaque.def_id.to_def_id();
-        let infcx = &cx.tcx.infer_ctxt().build();
+        let infcx = &cx.tcx.infer_ctxt().build(cx.typing_mode());
         // For every projection predicate in the opaque type's explicit bounds,
         // check that the type that we're assigning actually satisfies the bounds
         // of the associated type.
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index 0751d35cb9c3d..88878a018e7a6 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -1,6 +1,7 @@
 use std::iter;
 use std::ops::ControlFlow;
 
+use rustc_abi::{BackendRepr, TagEncoding, Variants, WrappingRange};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::DiagMessage;
 use rustc_hir::{Expr, ExprKind};
@@ -13,7 +14,6 @@ use rustc_session::{declare_lint, declare_lint_pass, impl_lint_pass};
 use rustc_span::def_id::LocalDefId;
 use rustc_span::symbol::sym;
 use rustc_span::{Span, Symbol, source_map};
-use rustc_target::abi::{Abi, TagEncoding, Variants, WrappingRange};
 use rustc_target::spec::abi::Abi as SpecAbi;
 use tracing::debug;
 use {rustc_ast as ast, rustc_hir as hir};
@@ -776,8 +776,8 @@ pub(crate) fn repr_nullable_ptr<'tcx>(
             bug!("should be able to compute the layout of non-polymorphic type");
         }
 
-        let field_ty_abi = &field_ty_layout.ok()?.abi;
-        if let Abi::Scalar(field_ty_scalar) = field_ty_abi {
+        let field_ty_abi = &field_ty_layout.ok()?.backend_repr;
+        if let BackendRepr::Scalar(field_ty_scalar) = field_ty_abi {
             match field_ty_scalar.valid_range(&tcx) {
                 WrappingRange { start: 0, end }
                     if end == field_ty_scalar.size(&tcx).unsigned_int_max() - 1 =>
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 20bf32d731e12..3e906f89c15c3 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -1559,8 +1559,10 @@ extern "C" LLVMModuleRef LLVMRustParseBitcodeForLTO(LLVMContextRef Context,
 extern "C" const char *LLVMRustGetSliceFromObjectDataByName(const char *data,
                                                             size_t len,
                                                             const char *name,
+                                                            size_t name_len,
                                                             size_t *out_len) {
   *out_len = 0;
+  auto Name = StringRef(name, name_len);
   auto Data = StringRef(data, len);
   auto Buffer = MemoryBufferRef(Data, ""); // The id is unused.
   file_magic Type = identify_magic(Buffer.getBuffer());
@@ -1571,8 +1573,8 @@ extern "C" const char *LLVMRustGetSliceFromObjectDataByName(const char *data,
     return nullptr;
   }
   for (const object::SectionRef &Sec : (*ObjFileOrError)->sections()) {
-    Expected<StringRef> Name = Sec.getName();
-    if (Name && *Name == name) {
+    Expected<StringRef> SecName = Sec.getName();
+    if (SecName && *SecName == Name) {
       Expected<StringRef> SectionOrError = Sec.getContents();
       if (!SectionOrError) {
         LLVMRustSetLastError(toString(SectionOrError.takeError()).c_str());
diff --git a/compiler/rustc_middle/src/query/plumbing.rs b/compiler/rustc_middle/src/query/plumbing.rs
index 564d274bc8b1e..57da5b39ba781 100644
--- a/compiler/rustc_middle/src/query/plumbing.rs
+++ b/compiler/rustc_middle/src/query/plumbing.rs
@@ -323,7 +323,7 @@ macro_rules! define_callbacks {
                 // Increase this limit if necessary, but do try to keep the size low if possible
                 #[cfg(target_pointer_width = "64")]
                 const _: () = {
-                    if mem::size_of::<Key<'static>>() > 72 {
+                    if mem::size_of::<Key<'static>>() > 80 {
                         panic!("{}", concat!(
                             "the query `",
                             stringify!($name),
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 5ae9c589ec4a5..5cbbc80ebfbb6 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -54,7 +54,6 @@ use rustc_type_ir::TyKind::*;
 use rustc_type_ir::fold::TypeFoldable;
 use rustc_type_ir::lang_items::TraitSolverLangItem;
 pub use rustc_type_ir::lift::Lift;
-use rustc_type_ir::solve::SolverMode;
 use rustc_type_ir::{CollectAndApply, Interner, TypeFlags, WithCachedTypeInfo, search_graph};
 use tracing::{debug, trace};
 
@@ -170,15 +169,8 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
         tracked.get(self)
     }
 
-    fn with_global_cache<R>(
-        self,
-        mode: SolverMode,
-        f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R,
-    ) -> R {
-        match mode {
-            SolverMode::Normal => f(&mut *self.new_solver_evaluation_cache.lock()),
-            SolverMode::Coherence => f(&mut *self.new_solver_coherence_evaluation_cache.lock()),
-        }
+    fn with_global_cache<R>(self, f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R) -> R {
+        f(&mut *self.new_solver_evaluation_cache.lock())
     }
 
     fn evaluation_is_concurrent(&self) -> bool {
@@ -629,6 +621,10 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
     ) -> ty::Binder<'tcx, T> {
         self.anonymize_bound_vars(binder)
     }
+
+    fn opaque_types_defined_by(self, defining_anchor: LocalDefId) -> Self::DefiningOpaqueTypes {
+        self.opaque_types_defined_by(defining_anchor)
+    }
 }
 
 macro_rules! bidirectional_lang_item_map {
@@ -1334,7 +1330,6 @@ pub struct GlobalCtxt<'tcx> {
 
     /// Caches the results of goal evaluation in the new solver.
     pub new_solver_evaluation_cache: Lock<search_graph::GlobalCache<TyCtxt<'tcx>>>,
-    pub new_solver_coherence_evaluation_cache: Lock<search_graph::GlobalCache<TyCtxt<'tcx>>>,
 
     pub canonical_param_env_cache: CanonicalParamEnvCache<'tcx>,
 
@@ -1561,7 +1556,6 @@ impl<'tcx> TyCtxt<'tcx> {
             selection_cache: Default::default(),
             evaluation_cache: Default::default(),
             new_solver_evaluation_cache: Default::default(),
-            new_solver_coherence_evaluation_cache: Default::default(),
             canonical_param_env_cache: Default::default(),
             data_layout,
             alloc_map: Lock::new(interpret::AllocMap::new()),
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index 2c7a3ffd04c8a..0560ffe058a37 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -4,8 +4,9 @@ use std::{cmp, fmt};
 
 use rustc_abi::Primitive::{self, Float, Int, Pointer};
 use rustc_abi::{
-    Abi, AddressSpace, Align, FieldsShape, HasDataLayout, Integer, LayoutCalculator, LayoutData,
-    PointeeInfo, PointerKind, ReprOptions, Scalar, Size, TagEncoding, TargetDataLayout, Variants,
+    AddressSpace, Align, BackendRepr, FieldsShape, HasDataLayout, Integer, LayoutCalculator,
+    LayoutData, PointeeInfo, PointerKind, ReprOptions, Scalar, Size, TagEncoding, TargetDataLayout,
+    Variants,
 };
 use rustc_error_messages::DiagMessage;
 use rustc_errors::{
@@ -757,7 +758,7 @@ where
                         Some(fields) => FieldsShape::Union(fields),
                         None => FieldsShape::Arbitrary { offsets: IndexVec::new(), memory_index: IndexVec::new() },
                     },
-                    abi: Abi::Uninhabited,
+                    backend_repr: BackendRepr::Uninhabited,
                     largest_niche: None,
                     align: tcx.data_layout.i8_align,
                     size: Size::ZERO,
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index b92fc864b49a7..bd32e5837b38f 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -100,7 +100,7 @@ pub use self::rvalue_scopes::RvalueScopes;
 pub use self::sty::{
     AliasTy, Article, Binder, BoundTy, BoundTyKind, BoundVariableKind, CanonicalPolyFnSig,
     CoroutineArgsExt, EarlyBinder, FnSig, InlineConstArgs, InlineConstArgsParts, ParamConst,
-    ParamTy, PolyFnSig, TyKind, TypeAndMut, UpvarArgs,
+    ParamTy, PolyFnSig, TyKind, TypeAndMut, TypingMode, UpvarArgs,
 };
 pub use self::trait_def::TraitDef;
 pub use self::typeck_results::{
diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs
index d8362ccc0a97c..a8327ebc17fee 100644
--- a/compiler/rustc_middle/src/ty/sty.rs
+++ b/compiler/rustc_middle/src/ty/sty.rs
@@ -40,6 +40,7 @@ pub type AliasTy<'tcx> = ir::AliasTy<TyCtxt<'tcx>>;
 pub type FnSig<'tcx> = ir::FnSig<TyCtxt<'tcx>>;
 pub type Binder<'tcx, T> = ir::Binder<TyCtxt<'tcx>, T>;
 pub type EarlyBinder<'tcx, T> = ir::EarlyBinder<TyCtxt<'tcx>, T>;
+pub type TypingMode<'tcx> = ir::TypingMode<TyCtxt<'tcx>>;
 
 pub trait Article {
     fn article(&self) -> &'static str;
diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
index fd949a533845e..2357dd7349057 100644
--- a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
+++ b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
@@ -13,7 +13,7 @@ use rustc_middle::ty::util::IntTypeExt;
 use rustc_middle::ty::{self, Ty, UpvarArgs};
 use rustc_span::source_map::Spanned;
 use rustc_span::{DUMMY_SP, Span};
-use rustc_target::abi::{Abi, FieldIdx, Primitive};
+use rustc_target::abi::{BackendRepr, FieldIdx, Primitive};
 use tracing::debug;
 
 use crate::build::expr::as_place::PlaceBase;
@@ -207,7 +207,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     );
                     let (op, ty) = (Operand::Move(discr), discr_ty);
 
-                    if let Abi::Scalar(scalar) = layout.unwrap().abi
+                    if let BackendRepr::Scalar(scalar) = layout.unwrap().backend_repr
                         && !scalar.is_always_valid(&this.tcx)
                         && let Primitive::Int(int_width, _signed) = scalar.primitive()
                     {
diff --git a/compiler/rustc_mir_build/src/build/mod.rs b/compiler/rustc_mir_build/src/build/mod.rs
index 8c20d2e0d3a62..e15ea4d8d8be2 100644
--- a/compiler/rustc_mir_build/src/build/mod.rs
+++ b/compiler/rustc_mir_build/src/build/mod.rs
@@ -16,7 +16,7 @@ use rustc_middle::middle::region;
 use rustc_middle::mir::*;
 use rustc_middle::query::TyCtxtAt;
 use rustc_middle::thir::{self, ExprId, LintLevel, LocalVarId, Param, ParamId, PatKind, Thir};
-use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt, TypeVisitableExt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_span::symbol::sym;
 use rustc_span::{Span, Symbol};
@@ -500,7 +500,9 @@ fn construct_fn<'tcx>(
         );
     }
 
-    let infcx = tcx.infer_ctxt().build();
+    // FIXME(#132279): This should be able to reveal opaque
+    // types defined during HIR typeck.
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let mut builder = Builder::new(
         thir,
         infcx,
@@ -578,7 +580,9 @@ fn construct_const<'a, 'tcx>(
         _ => span_bug!(tcx.def_span(def), "can't build MIR for {:?}", def),
     };
 
-    let infcx = tcx.infer_ctxt().build();
+    // FIXME(#132279): We likely want to be able to use the hidden types of
+    // opaques used by this function here.
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let mut builder =
         Builder::new(thir, infcx, def, hir_id, span, 0, const_ty, const_ty_span, None);
 
diff --git a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
index 8498df59ce653..f222a869c0344 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
@@ -79,6 +79,8 @@ enum LetSource {
     IfLetGuard,
     LetElse,
     WhileLet,
+    Else,
+    ElseIfLet,
 }
 
 struct MatchVisitor<'p, 'tcx> {
@@ -129,15 +131,20 @@ impl<'p, 'tcx> Visitor<'p, 'tcx> for MatchVisitor<'p, 'tcx> {
                 // Give a specific `let_source` for the condition.
                 let let_source = match ex.span.desugaring_kind() {
                     Some(DesugaringKind::WhileLoop) => LetSource::WhileLet,
-                    _ => LetSource::IfLet,
+                    _ => match self.let_source {
+                        LetSource::Else => LetSource::ElseIfLet,
+                        _ => LetSource::IfLet,
+                    },
                 };
                 self.with_let_source(let_source, |this| this.visit_expr(&self.thir[cond]));
                 self.with_let_source(LetSource::None, |this| {
                     this.visit_expr(&this.thir[then]);
-                    if let Some(else_) = else_opt {
-                        this.visit_expr(&this.thir[else_]);
-                    }
                 });
+                if let Some(else_) = else_opt {
+                    self.with_let_source(LetSource::Else, |this| {
+                        this.visit_expr(&this.thir[else_])
+                    });
+                }
                 return;
             }
             ExprKind::Match { scrutinee, scrutinee_hir_id: _, box ref arms, match_source } => {
@@ -573,9 +580,13 @@ impl<'p, 'tcx> MatchVisitor<'p, 'tcx> {
             // and we shouldn't lint.
             // For let guards inside a match, prefixes might use bindings of the match pattern,
             // so can't always be moved out.
+            // For `else if let`, an extra indentation level would be required to move the bindings.
             // FIXME: Add checking whether the bindings are actually used in the prefix,
             // and lint if they are not.
-            if !matches!(self.let_source, LetSource::WhileLet | LetSource::IfLetGuard) {
+            if !matches!(
+                self.let_source,
+                LetSource::WhileLet | LetSource::IfLetGuard | LetSource::ElseIfLet
+            ) {
                 // Emit the lint
                 let prefix = &chain_refutabilities[..until];
                 let span_start = prefix[0].unwrap().0;
@@ -906,8 +917,8 @@ fn report_irrefutable_let_patterns(
     }
 
     match source {
-        LetSource::None | LetSource::PlainLet => bug!(),
-        LetSource::IfLet => emit_diag!(IrrefutableLetPatternsIfLet),
+        LetSource::None | LetSource::PlainLet | LetSource::Else => bug!(),
+        LetSource::IfLet | LetSource::ElseIfLet => emit_diag!(IrrefutableLetPatternsIfLet),
         LetSource::IfLetGuard => emit_diag!(IrrefutableLetPatternsIfLetGuard),
         LetSource::LetElse => emit_diag!(IrrefutableLetPatternsLetElse),
         LetSource::WhileLet => emit_diag!(IrrefutableLetPatternsWhileLet),
diff --git a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
index 0dfa9168f7c80..c89f526aa1758 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
@@ -7,7 +7,7 @@ use rustc_infer::traits::Obligation;
 use rustc_middle::mir;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::thir::{FieldPat, Pat, PatKind};
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, ValTree};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, TypingMode, ValTree};
 use rustc_span::Span;
 use rustc_target::abi::{FieldIdx, VariantIdx};
 use rustc_trait_selection::traits::ObligationCause;
@@ -36,7 +36,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
         id: hir::HirId,
         span: Span,
     ) -> Box<Pat<'tcx>> {
-        let infcx = self.tcx.infer_ctxt().build();
+        // FIXME(#132279): We likely want to be able to reveal the hidden types
+        // of opaques defined in this function here.
+        let infcx = self.tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let mut convert = ConstToPat::new(self, id, span, infcx);
         convert.to_pat(c, ty)
     }
diff --git a/compiler/rustc_mir_dataflow/src/framework/mod.rs b/compiler/rustc_mir_dataflow/src/framework/mod.rs
index 959f1ea534090..8f81da8bb0499 100644
--- a/compiler/rustc_mir_dataflow/src/framework/mod.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/mod.rs
@@ -7,18 +7,17 @@
 //!
 //! The `impls` module contains several examples of dataflow analyses.
 //!
-//! Create an `Engine` for your analysis using the `into_engine` method on the `Analysis` trait,
-//! then call `iterate_to_fixpoint`. From there, you can use a `ResultsCursor` to inspect the
-//! fixpoint solution to your dataflow problem, or implement the `ResultsVisitor` interface and use
-//! `visit_results`. The following example uses the `ResultsCursor` approach.
+//! Then call `iterate_to_fixpoint` on your type that impls `Analysis` to get a `Results`. From
+//! there, you can use a `ResultsCursor` to inspect the fixpoint solution to your dataflow problem,
+//! or implement the `ResultsVisitor` interface and use `visit_results`. The following example uses
+//! the `ResultsCursor` approach.
 //!
 //! ```ignore (cross-crate-imports)
-//! use rustc_const_eval::dataflow::Analysis; // Makes `into_engine` available.
+//! use rustc_const_eval::dataflow::Analysis; // Makes `iterate_to_fixpoint` available.
 //!
 //! fn do_my_analysis(tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>) {
 //!     let analysis = MyAnalysis::new()
-//!         .into_engine(tcx, body)
-//!         .iterate_to_fixpoint()
+//!         .iterate_to_fixpoint(tcx, body, None)
 //!         .into_results_cursor(body);
 //!
 //!     // Print the dataflow state *after* each statement in the start block.
@@ -34,23 +33,29 @@
 
 use std::cmp::Ordering;
 
-use rustc_index::Idx;
+use rustc_data_structures::work_queue::WorkQueue;
 use rustc_index::bit_set::{BitSet, ChunkedBitSet, HybridBitSet};
-use rustc_middle::mir::{self, BasicBlock, CallReturnPlaces, Location, TerminatorEdges};
+use rustc_index::{Idx, IndexVec};
+use rustc_middle::bug;
+use rustc_middle::mir::{self, BasicBlock, CallReturnPlaces, Location, TerminatorEdges, traversal};
 use rustc_middle::ty::TyCtxt;
+use tracing::error;
+
+use self::results::write_graphviz_results;
+use super::fmt::DebugWithContext;
 
 mod cursor;
 mod direction;
-mod engine;
 pub mod fmt;
 pub mod graphviz;
 pub mod lattice;
+mod results;
 mod visitor;
 
 pub use self::cursor::ResultsCursor;
 pub use self::direction::{Backward, Direction, Forward};
-pub use self::engine::{Engine, Results};
 pub use self::lattice::{JoinSemiLattice, MaybeReachable};
+pub use self::results::Results;
 pub use self::visitor::{ResultsVisitable, ResultsVisitor, visit_results};
 
 /// Analysis domains are all bitsets of various kinds. This trait holds
@@ -223,26 +228,92 @@ pub trait Analysis<'tcx> {
 
     /* Extension methods */
 
-    /// Creates an `Engine` to find the fixpoint for this dataflow problem.
+    /// Finds the fixpoint for this dataflow problem.
     ///
     /// You shouldn't need to override this. Its purpose is to enable method chaining like so:
     ///
     /// ```ignore (cross-crate-imports)
     /// let results = MyAnalysis::new(tcx, body)
-    ///     .into_engine(tcx, body, def_id)
-    ///     .iterate_to_fixpoint()
+    ///     .iterate_to_fixpoint(tcx, body, None)
     ///     .into_results_cursor(body);
     /// ```
-    #[inline]
-    fn into_engine<'mir>(
-        self,
+    /// You can optionally add a `pass_name` to the graphviz output for this particular run of a
+    /// dataflow analysis. Some analyses are run multiple times in the compilation pipeline.
+    /// Without a `pass_name` to differentiates them, only the results for the latest run will be
+    /// saved.
+    fn iterate_to_fixpoint<'mir>(
+        mut self,
         tcx: TyCtxt<'tcx>,
         body: &'mir mir::Body<'tcx>,
-    ) -> Engine<'mir, 'tcx, Self>
+        pass_name: Option<&'static str>,
+    ) -> Results<'tcx, Self>
     where
         Self: Sized,
+        Self::Domain: DebugWithContext<Self>,
     {
-        Engine::new(tcx, body, self)
+        let mut entry_sets =
+            IndexVec::from_fn_n(|_| self.bottom_value(body), body.basic_blocks.len());
+        self.initialize_start_block(body, &mut entry_sets[mir::START_BLOCK]);
+
+        if Self::Direction::IS_BACKWARD && entry_sets[mir::START_BLOCK] != self.bottom_value(body) {
+            bug!("`initialize_start_block` is not yet supported for backward dataflow analyses");
+        }
+
+        let mut dirty_queue: WorkQueue<BasicBlock> = WorkQueue::with_none(body.basic_blocks.len());
+
+        if Self::Direction::IS_FORWARD {
+            for (bb, _) in traversal::reverse_postorder(body) {
+                dirty_queue.insert(bb);
+            }
+        } else {
+            // Reverse post-order on the reverse CFG may generate a better iteration order for
+            // backward dataflow analyses, but probably not enough to matter.
+            for (bb, _) in traversal::postorder(body) {
+                dirty_queue.insert(bb);
+            }
+        }
+
+        // `state` is not actually used between iterations;
+        // this is just an optimization to avoid reallocating
+        // every iteration.
+        let mut state = self.bottom_value(body);
+        while let Some(bb) = dirty_queue.pop() {
+            let bb_data = &body[bb];
+
+            // Set the state to the entry state of the block.
+            // This is equivalent to `state = entry_sets[bb].clone()`,
+            // but it saves an allocation, thus improving compile times.
+            state.clone_from(&entry_sets[bb]);
+
+            // Apply the block transfer function, using the cached one if it exists.
+            let edges = Self::Direction::apply_effects_in_block(&mut self, &mut state, bb, bb_data);
+
+            Self::Direction::join_state_into_successors_of(
+                &mut self,
+                body,
+                &mut state,
+                bb,
+                edges,
+                |target: BasicBlock, state: &Self::Domain| {
+                    let set_changed = entry_sets[target].join(state);
+                    if set_changed {
+                        dirty_queue.insert(target);
+                    }
+                },
+            );
+        }
+
+        let results = Results { analysis: self, entry_sets };
+
+        if tcx.sess.opts.unstable_opts.dump_mir_dataflow {
+            let (res, results) = write_graphviz_results(tcx, body, results, pass_name);
+            if let Err(e) = res {
+                error!("Failed to write graphviz dataflow results: {}", e);
+            }
+            results
+        } else {
+            results
+        }
     }
 }
 
diff --git a/compiler/rustc_mir_dataflow/src/framework/engine.rs b/compiler/rustc_mir_dataflow/src/framework/results.rs
similarity index 61%
rename from compiler/rustc_mir_dataflow/src/framework/engine.rs
rename to compiler/rustc_mir_dataflow/src/framework/results.rs
index cbd1083d037d2..366fcbf33ba3c 100644
--- a/compiler/rustc_mir_dataflow/src/framework/engine.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/results.rs
@@ -1,23 +1,19 @@
-//! A solver for dataflow problems.
+//! Dataflow analysis results.
 
 use std::ffi::OsString;
 use std::path::PathBuf;
 
-use rustc_data_structures::work_queue::WorkQueue;
 use rustc_hir::def_id::DefId;
 use rustc_index::IndexVec;
-use rustc_middle::bug;
 use rustc_middle::mir::{self, BasicBlock, create_dump_file, dump_enabled, traversal};
 use rustc_middle::ty::TyCtxt;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_span::symbol::{Symbol, sym};
-use tracing::{debug, error};
+use tracing::debug;
 use {rustc_ast as ast, rustc_graphviz as dot};
 
 use super::fmt::DebugWithContext;
-use super::{
-    Analysis, Direction, JoinSemiLattice, ResultsCursor, ResultsVisitor, graphviz, visit_results,
-};
+use super::{Analysis, ResultsCursor, ResultsVisitor, graphviz, visit_results};
 use crate::errors::{
     DuplicateValuesFor, PathMustEndInFilename, RequiresAnArgument, UnknownFormatter,
 };
@@ -65,124 +61,17 @@ where
         body: &'mir mir::Body<'tcx>,
         vis: &mut impl ResultsVisitor<'mir, 'tcx, Self, Domain = A::Domain>,
     ) {
-        let blocks = mir::traversal::reachable(body);
+        let blocks = traversal::reachable(body);
         visit_results(body, blocks.map(|(bb, _)| bb), self, vis)
     }
 }
 
-/// A solver for dataflow problems.
-pub struct Engine<'mir, 'tcx, A>
-where
-    A: Analysis<'tcx>,
-{
-    tcx: TyCtxt<'tcx>,
-    body: &'mir mir::Body<'tcx>,
-    entry_sets: IndexVec<BasicBlock, A::Domain>,
-    pass_name: Option<&'static str>,
-    analysis: A,
-}
-
-impl<'mir, 'tcx, A, D> Engine<'mir, 'tcx, A>
-where
-    A: Analysis<'tcx, Domain = D>,
-    D: Clone + JoinSemiLattice,
-{
-    /// Creates a new `Engine` to solve a dataflow problem with an arbitrary transfer
-    /// function.
-    pub(crate) fn new(tcx: TyCtxt<'tcx>, body: &'mir mir::Body<'tcx>, analysis: A) -> Self {
-        let mut entry_sets =
-            IndexVec::from_fn_n(|_| analysis.bottom_value(body), body.basic_blocks.len());
-        analysis.initialize_start_block(body, &mut entry_sets[mir::START_BLOCK]);
-
-        if A::Direction::IS_BACKWARD && entry_sets[mir::START_BLOCK] != analysis.bottom_value(body)
-        {
-            bug!("`initialize_start_block` is not yet supported for backward dataflow analyses");
-        }
-
-        Engine { analysis, tcx, body, pass_name: None, entry_sets }
-    }
-
-    /// Adds an identifier to the graphviz output for this particular run of a dataflow analysis.
-    ///
-    /// Some analyses are run multiple times in the compilation pipeline. Give them a `pass_name`
-    /// to differentiate them. Otherwise, only the results for the latest run will be saved.
-    pub fn pass_name(mut self, name: &'static str) -> Self {
-        self.pass_name = Some(name);
-        self
-    }
-
-    /// Computes the fixpoint for this dataflow problem and returns it.
-    pub fn iterate_to_fixpoint(self) -> Results<'tcx, A>
-    where
-        A::Domain: DebugWithContext<A>,
-    {
-        let Engine { mut analysis, body, mut entry_sets, tcx, pass_name } = self;
-
-        let mut dirty_queue: WorkQueue<BasicBlock> = WorkQueue::with_none(body.basic_blocks.len());
-
-        if A::Direction::IS_FORWARD {
-            for (bb, _) in traversal::reverse_postorder(body) {
-                dirty_queue.insert(bb);
-            }
-        } else {
-            // Reverse post-order on the reverse CFG may generate a better iteration order for
-            // backward dataflow analyses, but probably not enough to matter.
-            for (bb, _) in traversal::postorder(body) {
-                dirty_queue.insert(bb);
-            }
-        }
-
-        // `state` is not actually used between iterations;
-        // this is just an optimization to avoid reallocating
-        // every iteration.
-        let mut state = analysis.bottom_value(body);
-        while let Some(bb) = dirty_queue.pop() {
-            let bb_data = &body[bb];
-
-            // Set the state to the entry state of the block.
-            // This is equivalent to `state = entry_sets[bb].clone()`,
-            // but it saves an allocation, thus improving compile times.
-            state.clone_from(&entry_sets[bb]);
-
-            // Apply the block transfer function, using the cached one if it exists.
-            let edges =
-                A::Direction::apply_effects_in_block(&mut analysis, &mut state, bb, bb_data);
-
-            A::Direction::join_state_into_successors_of(
-                &mut analysis,
-                body,
-                &mut state,
-                bb,
-                edges,
-                |target: BasicBlock, state: &A::Domain| {
-                    let set_changed = entry_sets[target].join(state);
-                    if set_changed {
-                        dirty_queue.insert(target);
-                    }
-                },
-            );
-        }
-
-        let results = Results { analysis, entry_sets };
-
-        if tcx.sess.opts.unstable_opts.dump_mir_dataflow {
-            let (res, results) = write_graphviz_results(tcx, body, results, pass_name);
-            if let Err(e) = res {
-                error!("Failed to write graphviz dataflow results: {}", e);
-            }
-            results
-        } else {
-            results
-        }
-    }
-}
-
 // Graphviz
 
 /// Writes a DOT file containing the results of a dataflow analysis if the user requested it via
 /// `rustc_mir` attributes and `-Z dump-mir-dataflow`. The `Result` in and the `Results` out are
 /// the same.
-fn write_graphviz_results<'tcx, A>(
+pub(super) fn write_graphviz_results<'tcx, A>(
     tcx: TyCtxt<'tcx>,
     body: &mir::Body<'tcx>,
     results: Results<'tcx, A>,
diff --git a/compiler/rustc_mir_dataflow/src/lib.rs b/compiler/rustc_mir_dataflow/src/lib.rs
index b284f0308f979..b404e3bfb72c3 100644
--- a/compiler/rustc_mir_dataflow/src/lib.rs
+++ b/compiler/rustc_mir_dataflow/src/lib.rs
@@ -18,9 +18,9 @@ pub use self::drop_flag_effects::{
     move_path_children_matching, on_all_children_bits, on_lookup_result_bits,
 };
 pub use self::framework::{
-    Analysis, Backward, Direction, Engine, Forward, GenKill, JoinSemiLattice, MaybeReachable,
-    Results, ResultsCursor, ResultsVisitable, ResultsVisitor, SwitchIntEdgeEffects, fmt, graphviz,
-    lattice, visit_results,
+    Analysis, Backward, Direction, Forward, GenKill, JoinSemiLattice, MaybeReachable, Results,
+    ResultsCursor, ResultsVisitable, ResultsVisitor, SwitchIntEdgeEffects, fmt, graphviz, lattice,
+    visit_results,
 };
 use self::move_paths::MoveData;
 
diff --git a/compiler/rustc_mir_dataflow/src/rustc_peek.rs b/compiler/rustc_mir_dataflow/src/rustc_peek.rs
index 5727517bd612a..99d0ccde1052c 100644
--- a/compiler/rustc_mir_dataflow/src/rustc_peek.rs
+++ b/compiler/rustc_mir_dataflow/src/rustc_peek.rs
@@ -43,31 +43,28 @@ pub fn sanity_check<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>) {
     let move_data = MoveData::gather_moves(body, tcx, |_| true);
 
     if has_rustc_mir_with(tcx, def_id, sym::rustc_peek_maybe_init).is_some() {
-        let flow_inits = MaybeInitializedPlaces::new(tcx, body, &move_data)
-            .into_engine(tcx, body)
-            .iterate_to_fixpoint();
+        let flow_inits =
+            MaybeInitializedPlaces::new(tcx, body, &move_data).iterate_to_fixpoint(tcx, body, None);
 
         sanity_check_via_rustc_peek(tcx, flow_inits.into_results_cursor(body));
     }
 
     if has_rustc_mir_with(tcx, def_id, sym::rustc_peek_maybe_uninit).is_some() {
         let flow_uninits = MaybeUninitializedPlaces::new(tcx, body, &move_data)
-            .into_engine(tcx, body)
-            .iterate_to_fixpoint();
+            .iterate_to_fixpoint(tcx, body, None);
 
         sanity_check_via_rustc_peek(tcx, flow_uninits.into_results_cursor(body));
     }
 
     if has_rustc_mir_with(tcx, def_id, sym::rustc_peek_definite_init).is_some() {
-        let flow_def_inits = DefinitelyInitializedPlaces::new(body, &move_data)
-            .into_engine(tcx, body)
-            .iterate_to_fixpoint();
+        let flow_def_inits =
+            DefinitelyInitializedPlaces::new(body, &move_data).iterate_to_fixpoint(tcx, body, None);
 
         sanity_check_via_rustc_peek(tcx, flow_def_inits.into_results_cursor(body));
     }
 
     if has_rustc_mir_with(tcx, def_id, sym::rustc_peek_liveness).is_some() {
-        let flow_liveness = MaybeLiveLocals.into_engine(tcx, body).iterate_to_fixpoint();
+        let flow_liveness = MaybeLiveLocals.iterate_to_fixpoint(tcx, body, None);
 
         sanity_check_via_rustc_peek(tcx, flow_liveness.into_results_cursor(body));
     }
diff --git a/compiler/rustc_mir_dataflow/src/value_analysis.rs b/compiler/rustc_mir_dataflow/src/value_analysis.rs
index f7d4a082779b7..80151b8ba2dec 100644
--- a/compiler/rustc_mir_dataflow/src/value_analysis.rs
+++ b/compiler/rustc_mir_dataflow/src/value_analysis.rs
@@ -858,7 +858,7 @@ impl<'tcx> Map<'tcx> {
             // Allocate a value slot if it doesn't have one, and the user requested one.
             assert!(place_info.value_index.is_none());
             if let Ok(layout) = tcx.layout_of(param_env.and(place_info.ty))
-                && layout.abi.is_scalar()
+                && layout.backend_repr.is_scalar()
             {
                 place_info.value_index = Some(self.value_count.into());
                 self.value_count += 1;
diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs
index cd29105897778..6d5665b43317f 100644
--- a/compiler/rustc_mir_transform/src/coroutine.rs
+++ b/compiler/rustc_mir_transform/src/coroutine.rs
@@ -64,7 +64,7 @@ use rustc_index::{Idx, IndexVec};
 use rustc_middle::mir::visit::{MutVisitor, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::{
-    self, CoroutineArgs, CoroutineArgsExt, GenericArgsRef, InstanceKind, Ty, TyCtxt,
+    self, CoroutineArgs, CoroutineArgsExt, GenericArgsRef, InstanceKind, Ty, TyCtxt, TypingMode,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_mir_dataflow::Analysis;
@@ -666,14 +666,13 @@ fn locals_live_across_suspend_points<'tcx>(
     // Calculate when MIR locals have live storage. This gives us an upper bound of their
     // lifetimes.
     let mut storage_live = MaybeStorageLive::new(std::borrow::Cow::Borrowed(always_live_locals))
-        .into_engine(tcx, body)
-        .iterate_to_fixpoint()
+        .iterate_to_fixpoint(tcx, body, None)
         .into_results_cursor(body);
 
     // Calculate the MIR locals which have been previously
     // borrowed (even if they are still active).
     let borrowed_locals_results =
-        MaybeBorrowedLocals.into_engine(tcx, body).pass_name("coroutine").iterate_to_fixpoint();
+        MaybeBorrowedLocals.iterate_to_fixpoint(tcx, body, Some("coroutine"));
 
     let mut borrowed_locals_cursor = borrowed_locals_results.clone().into_results_cursor(body);
 
@@ -681,16 +680,12 @@ fn locals_live_across_suspend_points<'tcx>(
     // for.
     let mut requires_storage_cursor =
         MaybeRequiresStorage::new(borrowed_locals_results.into_results_cursor(body))
-            .into_engine(tcx, body)
-            .iterate_to_fixpoint()
+            .iterate_to_fixpoint(tcx, body, None)
             .into_results_cursor(body);
 
     // Calculate the liveness of MIR locals ignoring borrows.
-    let mut liveness = MaybeLiveLocals
-        .into_engine(tcx, body)
-        .pass_name("coroutine")
-        .iterate_to_fixpoint()
-        .into_results_cursor(body);
+    let mut liveness =
+        MaybeLiveLocals.iterate_to_fixpoint(tcx, body, Some("coroutine")).into_results_cursor(body);
 
     let mut storage_liveness_map = IndexVec::from_elem(None, &body.basic_blocks);
     let mut live_locals_at_suspension_points = Vec::new();
@@ -1501,7 +1496,11 @@ fn check_field_tys_sized<'tcx>(
         return;
     }
 
-    let infcx = tcx.infer_ctxt().ignoring_regions().build();
+    // FIXME(#132279): @lcnr believes that we may want to support coroutines
+    // whose `Sized`-ness relies on the hidden types of opaques defined by the
+    // parent function. In this case we'd have to be able to reveal only these
+    // opaques here.
+    let infcx = tcx.infer_ctxt().ignoring_regions().build(TypingMode::non_body_analysis());
     let param_env = tcx.param_env(def_id);
 
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
index 002216f50f2d1..c084b20772faa 100644
--- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
+++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
@@ -2,6 +2,7 @@
 //!
 //! Currently, this pass only propagates scalar values.
 
+use rustc_abi::{BackendRepr, FIRST_VARIANT, FieldIdx, Size, VariantIdx};
 use rustc_const_eval::const_eval::{DummyMachine, throw_machine_stop_str};
 use rustc_const_eval::interpret::{
     ImmTy, Immediate, InterpCx, OpTy, PlaceTy, Projectable, interp_ok,
@@ -20,7 +21,6 @@ use rustc_mir_dataflow::value_analysis::{
 };
 use rustc_mir_dataflow::{Analysis, Results, ResultsVisitor};
 use rustc_span::DUMMY_SP;
-use rustc_target::abi::{Abi, FIRST_VARIANT, FieldIdx, Size, VariantIdx};
 use tracing::{debug, debug_span, instrument};
 
 // These constants are somewhat random guesses and have not been optimized.
@@ -59,7 +59,7 @@ impl<'tcx> crate::MirPass<'tcx> for DataflowConstProp {
         // Perform the actual dataflow analysis.
         let analysis = ConstAnalysis::new(tcx, body, map);
         let mut results = debug_span!("analyze")
-            .in_scope(|| analysis.wrap().into_engine(tcx, body).iterate_to_fixpoint());
+            .in_scope(|| analysis.wrap().iterate_to_fixpoint(tcx, body, None));
 
         // Collect results and patch the body afterwards.
         let mut visitor = Collector::new(tcx, &body.local_decls);
@@ -457,7 +457,7 @@ impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> {
                     // a pair and sometimes not. But as a hack we always return a pair
                     // and just make the 2nd component `Bottom` when it does not exist.
                     Some(val) => {
-                        if matches!(val.layout.abi, Abi::ScalarPair(..)) {
+                        if matches!(val.layout.backend_repr, BackendRepr::ScalarPair(..)) {
                             let (val, overflow) = val.to_scalar_pair();
                             (FlatSet::Elem(val), FlatSet::Elem(overflow))
                         } else {
@@ -470,7 +470,7 @@ impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> {
             // Exactly one side is known, attempt some algebraic simplifications.
             (FlatSet::Elem(const_arg), _) | (_, FlatSet::Elem(const_arg)) => {
                 let layout = const_arg.layout;
-                if !matches!(layout.abi, rustc_target::abi::Abi::Scalar(..)) {
+                if !matches!(layout.backend_repr, rustc_target::abi::BackendRepr::Scalar(..)) {
                     return (FlatSet::Top, FlatSet::Top);
                 }
 
@@ -589,13 +589,13 @@ impl<'a, 'tcx> Collector<'a, 'tcx> {
         }
 
         let place = map.find(place.as_ref())?;
-        if layout.abi.is_scalar()
+        if layout.backend_repr.is_scalar()
             && let Some(value) = propagatable_scalar(place, state, map)
         {
             return Some(Const::Val(ConstValue::Scalar(value), ty));
         }
 
-        if matches!(layout.abi, Abi::Scalar(..) | Abi::ScalarPair(..)) {
+        if matches!(layout.backend_repr, BackendRepr::Scalar(..) | BackendRepr::ScalarPair(..)) {
             let alloc_id = ecx
                 .intern_with_temp_alloc(layout, |ecx, dest| {
                     try_write_constant(ecx, dest, place, ty, state, map)
@@ -641,7 +641,7 @@ fn try_write_constant<'tcx>(
     }
 
     // Fast path for scalars.
-    if layout.abi.is_scalar()
+    if layout.backend_repr.is_scalar()
         && let Some(value) = propagatable_scalar(place, state, map)
     {
         return ecx.write_immediate(Immediate::Scalar(value), dest);
diff --git a/compiler/rustc_mir_transform/src/dead_store_elimination.rs b/compiler/rustc_mir_transform/src/dead_store_elimination.rs
index edffe6ce78f67..2898f82e25c38 100644
--- a/compiler/rustc_mir_transform/src/dead_store_elimination.rs
+++ b/compiler/rustc_mir_transform/src/dead_store_elimination.rs
@@ -37,8 +37,7 @@ fn eliminate<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
     always_live.union(&borrowed_locals);
 
     let mut live = MaybeTransitiveLiveLocals::new(&always_live)
-        .into_engine(tcx, body)
-        .iterate_to_fixpoint()
+        .iterate_to_fixpoint(tcx, body, None)
         .into_results_cursor(body);
 
     // For blocks with a call terminator, if an argument copy can be turned into a move,
diff --git a/compiler/rustc_mir_transform/src/dest_prop.rs b/compiler/rustc_mir_transform/src/dest_prop.rs
index ad83c0295baec..beeab0d4a666b 100644
--- a/compiler/rustc_mir_transform/src/dest_prop.rs
+++ b/compiler/rustc_mir_transform/src/dest_prop.rs
@@ -169,10 +169,7 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
 
         let borrowed = rustc_mir_dataflow::impls::borrowed_locals(body);
 
-        let live = MaybeLiveLocals
-            .into_engine(tcx, body)
-            .pass_name("MaybeLiveLocals-DestinationPropagation")
-            .iterate_to_fixpoint();
+        let live = MaybeLiveLocals.iterate_to_fixpoint(tcx, body, Some("MaybeLiveLocals-DestProp"));
         let points = DenseLocationMap::new(body);
         let mut live = save_as_intervals(&points, body, live);
 
diff --git a/compiler/rustc_mir_transform/src/elaborate_drops.rs b/compiler/rustc_mir_transform/src/elaborate_drops.rs
index 30e1ac05e039c..58e1db194380f 100644
--- a/compiler/rustc_mir_transform/src/elaborate_drops.rs
+++ b/compiler/rustc_mir_transform/src/elaborate_drops.rs
@@ -64,18 +64,14 @@ impl<'tcx> crate::MirPass<'tcx> for ElaborateDrops {
 
             let mut inits = MaybeInitializedPlaces::new(tcx, body, &env.move_data)
                 .skipping_unreachable_unwind()
-                .into_engine(tcx, body)
-                .pass_name("elaborate_drops")
-                .iterate_to_fixpoint()
+                .iterate_to_fixpoint(tcx, body, Some("elaborate_drops"))
                 .into_results_cursor(body);
             let dead_unwinds = compute_dead_unwinds(body, &mut inits);
 
             let uninits = MaybeUninitializedPlaces::new(tcx, body, &env.move_data)
                 .mark_inactive_variants_as_uninit()
                 .skipping_unreachable_unwind(dead_unwinds)
-                .into_engine(tcx, body)
-                .pass_name("elaborate_drops")
-                .iterate_to_fixpoint()
+                .iterate_to_fixpoint(tcx, body, Some("elaborate_drops"))
                 .into_results_cursor(body);
 
             let drop_flags = IndexVec::from_elem(None, &env.move_data.move_paths);
diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs
index 79c62372df028..8a646d8cbfef5 100644
--- a/compiler/rustc_mir_transform/src/gvn.rs
+++ b/compiler/rustc_mir_transform/src/gvn.rs
@@ -85,6 +85,7 @@
 use std::borrow::Cow;
 
 use either::Either;
+use rustc_abi::{self as abi, BackendRepr, FIRST_VARIANT, FieldIdx, Primitive, Size, VariantIdx};
 use rustc_const_eval::const_eval::DummyMachine;
 use rustc_const_eval::interpret::{
     ImmTy, Immediate, InterpCx, MemPlaceMeta, MemoryKind, OpTy, Projectable, Scalar,
@@ -103,7 +104,6 @@ use rustc_middle::ty::layout::{HasParamEnv, LayoutOf};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::DUMMY_SP;
 use rustc_span::def_id::DefId;
-use rustc_target::abi::{self, Abi, FIRST_VARIANT, FieldIdx, Primitive, Size, VariantIdx};
 use smallvec::SmallVec;
 use tracing::{debug, instrument, trace};
 
@@ -427,7 +427,10 @@ impl<'body, 'tcx> VnState<'body, 'tcx> {
                     };
                     let ptr_imm = Immediate::new_pointer_with_meta(data, meta, &self.ecx);
                     ImmTy::from_immediate(ptr_imm, ty).into()
-                } else if matches!(ty.abi, Abi::Scalar(..) | Abi::ScalarPair(..)) {
+                } else if matches!(
+                    ty.backend_repr,
+                    BackendRepr::Scalar(..) | BackendRepr::ScalarPair(..)
+                ) {
                     let dest = self.ecx.allocate(ty, MemoryKind::Stack).discard_err()?;
                     let variant_dest = if let Some(variant) = variant {
                         self.ecx.project_downcast(&dest, variant).discard_err()?
@@ -573,12 +576,12 @@ impl<'body, 'tcx> VnState<'body, 'tcx> {
                     // limited transmutes: it only works between types with the same layout, and
                     // cannot transmute pointers to integers.
                     if value.as_mplace_or_imm().is_right() {
-                        let can_transmute = match (value.layout.abi, to.abi) {
-                            (Abi::Scalar(s1), Abi::Scalar(s2)) => {
+                        let can_transmute = match (value.layout.backend_repr, to.backend_repr) {
+                            (BackendRepr::Scalar(s1), BackendRepr::Scalar(s2)) => {
                                 s1.size(&self.ecx) == s2.size(&self.ecx)
                                     && !matches!(s1.primitive(), Primitive::Pointer(..))
                             }
-                            (Abi::ScalarPair(a1, b1), Abi::ScalarPair(a2, b2)) => {
+                            (BackendRepr::ScalarPair(a1, b1), BackendRepr::ScalarPair(a2, b2)) => {
                                 a1.size(&self.ecx) == a2.size(&self.ecx) &&
                                 b1.size(&self.ecx) == b2.size(&self.ecx) &&
                                 // The alignment of the second component determines its offset, so that also needs to match.
@@ -1241,7 +1244,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> {
 
         let as_bits = |value| {
             let constant = self.evaluated[value].as_ref()?;
-            if layout.abi.is_scalar() {
+            if layout.backend_repr.is_scalar() {
                 let scalar = self.ecx.read_scalar(constant).discard_err()?;
                 scalar.to_bits(constant.layout.size).discard_err()
             } else {
@@ -1497,12 +1500,12 @@ fn op_to_prop_const<'tcx>(
 
     // Do not synthetize too large constants. Codegen will just memcpy them, which we'd like to
     // avoid.
-    if !matches!(op.layout.abi, Abi::Scalar(..) | Abi::ScalarPair(..)) {
+    if !matches!(op.layout.backend_repr, BackendRepr::Scalar(..) | BackendRepr::ScalarPair(..)) {
         return None;
     }
 
     // If this constant has scalar ABI, return it as a `ConstValue::Scalar`.
-    if let Abi::Scalar(abi::Scalar::Initialized { .. }) = op.layout.abi
+    if let BackendRepr::Scalar(abi::Scalar::Initialized { .. }) = op.layout.backend_repr
         && let Some(scalar) = ecx.read_scalar(op).discard_err()
     {
         if !scalar.try_to_scalar_int().is_ok() {
diff --git a/compiler/rustc_mir_transform/src/known_panics_lint.rs b/compiler/rustc_mir_transform/src/known_panics_lint.rs
index 08923748eb275..0604665642aba 100644
--- a/compiler/rustc_mir_transform/src/known_panics_lint.rs
+++ b/compiler/rustc_mir_transform/src/known_panics_lint.rs
@@ -4,6 +4,7 @@
 
 use std::fmt::Debug;
 
+use rustc_abi::{BackendRepr, FieldIdx, HasDataLayout, Size, TargetDataLayout, VariantIdx};
 use rustc_const_eval::const_eval::DummyMachine;
 use rustc_const_eval::interpret::{
     ImmTy, InterpCx, InterpResult, Projectable, Scalar, format_interp_error, interp_ok,
@@ -19,7 +20,6 @@ use rustc_middle::mir::*;
 use rustc_middle::ty::layout::{LayoutError, LayoutOf, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::{self, ConstInt, ParamEnv, ScalarInt, Ty, TyCtxt, TypeVisitableExt};
 use rustc_span::Span;
-use rustc_target::abi::{Abi, FieldIdx, HasDataLayout, Size, TargetDataLayout, VariantIdx};
 use tracing::{debug, instrument, trace};
 
 use crate::errors::{AssertLint, AssertLintKind};
@@ -557,7 +557,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                 let right = self.use_ecx(|this| this.ecx.read_immediate(&right))?;
 
                 let val = self.use_ecx(|this| this.ecx.binary_op(bin_op, &left, &right))?;
-                if matches!(val.layout.abi, Abi::ScalarPair(..)) {
+                if matches!(val.layout.backend_repr, BackendRepr::ScalarPair(..)) {
                     // FIXME `Value` should properly support pairs in `Immediate`... but currently
                     // it does not.
                     let (val, overflow) = val.to_pair(&self.ecx);
@@ -651,9 +651,9 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                     let to = self.ecx.layout_of(to).ok()?;
                     // `offset` for immediates only supports scalar/scalar-pair ABIs,
                     // so bail out if the target is not one.
-                    match (value.layout.abi, to.abi) {
-                        (Abi::Scalar(..), Abi::Scalar(..)) => {}
-                        (Abi::ScalarPair(..), Abi::ScalarPair(..)) => {}
+                    match (value.layout.backend_repr, to.backend_repr) {
+                        (BackendRepr::Scalar(..), BackendRepr::Scalar(..)) => {}
+                        (BackendRepr::ScalarPair(..), BackendRepr::ScalarPair(..)) => {}
                         _ => return None,
                     }
 
diff --git a/compiler/rustc_mir_transform/src/lint.rs b/compiler/rustc_mir_transform/src/lint.rs
index 23733994a8b4a..d8ff1cfc90b58 100644
--- a/compiler/rustc_mir_transform/src/lint.rs
+++ b/compiler/rustc_mir_transform/src/lint.rs
@@ -17,13 +17,11 @@ pub(super) fn lint_body<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>, when: String
     let always_live_locals = &always_storage_live_locals(body);
 
     let maybe_storage_live = MaybeStorageLive::new(Cow::Borrowed(always_live_locals))
-        .into_engine(tcx, body)
-        .iterate_to_fixpoint()
+        .iterate_to_fixpoint(tcx, body, None)
         .into_results_cursor(body);
 
     let maybe_storage_dead = MaybeStorageDead::new(Cow::Borrowed(always_live_locals))
-        .into_engine(tcx, body)
-        .iterate_to_fixpoint()
+        .iterate_to_fixpoint(tcx, body, None)
         .into_results_cursor(body);
 
     let mut lint = Lint {
diff --git a/compiler/rustc_mir_transform/src/ref_prop.rs b/compiler/rustc_mir_transform/src/ref_prop.rs
index 53e53d9d5ba8b..b11b503e8d430 100644
--- a/compiler/rustc_mir_transform/src/ref_prop.rs
+++ b/compiler/rustc_mir_transform/src/ref_prop.rs
@@ -126,8 +126,7 @@ fn compute_replacement<'tcx>(
     // Compute `MaybeStorageDead` dataflow to check that we only replace when the pointee is
     // definitely live.
     let mut maybe_dead = MaybeStorageDead::new(Cow::Owned(always_live_locals))
-        .into_engine(tcx, body)
-        .iterate_to_fixpoint()
+        .iterate_to_fixpoint(tcx, body, None)
         .into_results_cursor(body);
 
     // Map for each local to the pointee.
diff --git a/compiler/rustc_mir_transform/src/remove_uninit_drops.rs b/compiler/rustc_mir_transform/src/remove_uninit_drops.rs
index 09969a4c7cc7f..55dd96100b0a6 100644
--- a/compiler/rustc_mir_transform/src/remove_uninit_drops.rs
+++ b/compiler/rustc_mir_transform/src/remove_uninit_drops.rs
@@ -22,9 +22,7 @@ impl<'tcx> crate::MirPass<'tcx> for RemoveUninitDrops {
         let move_data = MoveData::gather_moves(body, tcx, |ty| ty.needs_drop(tcx, param_env));
 
         let mut maybe_inits = MaybeInitializedPlaces::new(tcx, body, &move_data)
-            .into_engine(tcx, body)
-            .pass_name("remove_uninit_drops")
-            .iterate_to_fixpoint()
+            .iterate_to_fixpoint(tcx, body, Some("remove_uninit_drops"))
             .into_results_cursor(body);
 
         let mut to_remove = vec![];
diff --git a/compiler/rustc_mir_transform/src/validate.rs b/compiler/rustc_mir_transform/src/validate.rs
index 25e68f44456b8..77356723c466b 100644
--- a/compiler/rustc_mir_transform/src/validate.rs
+++ b/compiler/rustc_mir_transform/src/validate.rs
@@ -12,7 +12,7 @@ use rustc_middle::mir::*;
 use rustc_middle::ty::adjustment::PointerCoercion;
 use rustc_middle::ty::{
     self, CoroutineArgsExt, InstanceKind, ParamEnv, ScalarInt, Ty, TyCtxt, TypeVisitableExt,
-    Variance,
+    TypingMode, Variance,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_target::abi::{FIRST_VARIANT, Size};
@@ -606,7 +606,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             return true;
         }
 
-        let infcx = self.tcx.infer_ctxt().build();
+        let infcx = self.tcx.infer_ctxt().build(TypingMode::from_param_env(self.param_env));
         let ocx = ObligationCtxt::new(&infcx);
         ocx.register_obligation(Obligation::new(
             self.tcx,
diff --git a/compiler/rustc_next_trait_solver/src/delegate.rs b/compiler/rustc_next_trait_solver/src/delegate.rs
index 4da1e7fa711b5..f7fbfed5b8e38 100644
--- a/compiler/rustc_next_trait_solver/src/delegate.rs
+++ b/compiler/rustc_next_trait_solver/src/delegate.rs
@@ -1,7 +1,7 @@
 use std::ops::Deref;
 
 use rustc_type_ir::fold::TypeFoldable;
-use rustc_type_ir::solve::{Certainty, Goal, NoSolution, SolverMode};
+use rustc_type_ir::solve::{Certainty, Goal, NoSolution};
 use rustc_type_ir::{self as ty, InferCtxtLike, Interner};
 
 pub trait SolverDelegate: Deref<Target = <Self as SolverDelegate>::Infcx> + Sized {
@@ -15,7 +15,6 @@ pub trait SolverDelegate: Deref<Target = <Self as SolverDelegate>::Infcx> + Size
 
     fn build_with_canonical<V>(
         cx: Self::Interner,
-        solver_mode: SolverMode,
         canonical: &ty::CanonicalQueryInput<Self::Interner, V>,
     ) -> (Self, V, ty::CanonicalVarValues<Self::Interner>)
     where
@@ -93,7 +92,6 @@ pub trait SolverDelegate: Deref<Target = <Self as SolverDelegate>::Infcx> + Size
 
     fn fetch_eligible_assoc_item(
         &self,
-        param_env: <Self::Interner as Interner>::ParamEnv,
         goal_trait_ref: ty::TraitRef<Self::Interner>,
         trait_assoc_def_id: <Self::Interner as Interner>::DefId,
         impl_def_id: <Self::Interner as Interner>::DefId,
diff --git a/compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs b/compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs
index f6a5f20a639ec..ebf7372926f8a 100644
--- a/compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs
@@ -8,14 +8,14 @@ use rustc_type_ir::inherent::*;
 use rustc_type_ir::lang_items::TraitSolverLangItem;
 use rustc_type_ir::solve::inspect;
 use rustc_type_ir::visit::TypeVisitableExt as _;
-use rustc_type_ir::{self as ty, Interner, Upcast as _, elaborate};
+use rustc_type_ir::{self as ty, Interner, TypingMode, Upcast as _, elaborate};
 use tracing::{debug, instrument};
 
 use crate::delegate::SolverDelegate;
 use crate::solve::inspect::ProbeKind;
 use crate::solve::{
     BuiltinImplSource, CandidateSource, CanonicalResponse, Certainty, EvalCtxt, Goal, GoalSource,
-    MaybeCause, NoSolution, QueryResult, SolverMode,
+    MaybeCause, NoSolution, QueryResult,
 };
 
 /// A candidate is a possible way to prove a goal.
@@ -328,11 +328,12 @@ where
 
         let mut candidates = vec![];
 
-        if self.solver_mode() == SolverMode::Coherence {
+        if let TypingMode::Coherence = self.typing_mode(goal.param_env) {
             if let Ok(candidate) = self.consider_coherence_unknowable_candidate(goal) {
                 return vec![candidate];
             }
         }
+
         self.assemble_impl_candidates(goal, &mut candidates);
 
         self.assemble_builtin_impl_candidates(goal, &mut candidates);
@@ -343,8 +344,11 @@ where
 
         self.assemble_param_env_candidates(goal, &mut candidates);
 
-        if self.solver_mode() == SolverMode::Normal {
-            self.discard_impls_shadowed_by_env(goal, &mut candidates);
+        match self.typing_mode(goal.param_env) {
+            TypingMode::Coherence => {}
+            TypingMode::Analysis { .. } | TypingMode::PostAnalysis => {
+                self.discard_impls_shadowed_by_env(goal, &mut candidates);
+            }
         }
 
         candidates
diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
index e2fd0dd2a25fa..2f50070d43883 100644
--- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/canonical.rs
@@ -55,6 +55,7 @@ where
         &self,
         goal: Goal<I, T>,
     ) -> (Vec<I::GenericArg>, CanonicalInput<I, T>) {
+        let param_env_for_debug_assertion = goal.param_env;
         let opaque_types = self.delegate.clone_opaque_types_for_query_response();
         let (goal, opaque_types) =
             (goal, opaque_types).fold_with(&mut EagerResolver::new(self.delegate));
@@ -73,7 +74,7 @@ where
         );
         let query_input = ty::CanonicalQueryInput {
             canonical,
-            defining_opaque_types: self.delegate.defining_opaque_types(),
+            typing_mode: self.typing_mode(param_env_for_debug_assertion),
         };
         (orig_values, query_input)
     }
diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
index 7608253882a27..8685896715e1e 100644
--- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs
@@ -10,7 +10,7 @@ use rustc_type_ir::inherent::*;
 use rustc_type_ir::relate::Relate;
 use rustc_type_ir::relate::solver_relating::RelateExt;
 use rustc_type_ir::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor};
-use rustc_type_ir::{self as ty, CanonicalVarValues, InferCtxtLike, Interner};
+use rustc_type_ir::{self as ty, CanonicalVarValues, InferCtxtLike, Interner, TypingMode};
 use rustc_type_ir_macros::{Lift_Generic, TypeFoldable_Generic, TypeVisitable_Generic};
 use tracing::{instrument, trace};
 
@@ -21,7 +21,6 @@ use crate::solve::search_graph::SearchGraph;
 use crate::solve::{
     CanonicalInput, Certainty, FIXPOINT_STEP_LIMIT, Goal, GoalEvaluationKind, GoalSource,
     HasChanged, NestedNormalizationGoals, NoSolution, PredefinedOpaquesData, QueryResult,
-    SolverMode,
 };
 
 pub(super) mod canonical;
@@ -215,8 +214,8 @@ where
     D: SolverDelegate<Interner = I>,
     I: Interner,
 {
-    pub(super) fn solver_mode(&self) -> SolverMode {
-        self.search_graph.solver_mode()
+    pub(super) fn typing_mode(&self, param_env_for_debug_assertion: I::ParamEnv) -> TypingMode<I> {
+        self.delegate.typing_mode(param_env_for_debug_assertion)
     }
 
     pub(super) fn set_is_normalizes_to_goal(&mut self) {
@@ -232,7 +231,7 @@ where
         generate_proof_tree: GenerateProofTree,
         f: impl FnOnce(&mut EvalCtxt<'_, D>) -> R,
     ) -> (R, Option<inspect::GoalEvaluation<I>>) {
-        let mut search_graph = SearchGraph::new(delegate.solver_mode(), root_depth);
+        let mut search_graph = SearchGraph::new(root_depth);
 
         let mut ecx = EvalCtxt {
             delegate,
@@ -279,7 +278,7 @@ where
         f: impl FnOnce(&mut EvalCtxt<'_, D>, Goal<I, I::Predicate>) -> R,
     ) -> R {
         let (ref delegate, input, var_values) =
-            SolverDelegate::build_with_canonical(cx, search_graph.solver_mode(), &canonical_input);
+            SolverDelegate::build_with_canonical(cx, &canonical_input);
 
         let mut ecx = EvalCtxt {
             delegate,
@@ -942,21 +941,11 @@ where
 
     pub(super) fn fetch_eligible_assoc_item(
         &self,
-        param_env: I::ParamEnv,
         goal_trait_ref: ty::TraitRef<I>,
         trait_assoc_def_id: I::DefId,
         impl_def_id: I::DefId,
     ) -> Result<Option<I::DefId>, NoSolution> {
-        self.delegate.fetch_eligible_assoc_item(
-            param_env,
-            goal_trait_ref,
-            trait_assoc_def_id,
-            impl_def_id,
-        )
-    }
-
-    pub(super) fn can_define_opaque_ty(&self, def_id: I::LocalDefId) -> bool {
-        self.delegate.defining_opaque_types().contains(&def_id)
+        self.delegate.fetch_eligible_assoc_item(goal_trait_ref, trait_assoc_def_id, impl_def_id)
     }
 
     pub(super) fn insert_hidden_type(
diff --git a/compiler/rustc_next_trait_solver/src/solve/normalizes_to/mod.rs b/compiler/rustc_next_trait_solver/src/solve/normalizes_to/mod.rs
index 7287cdf74bf45..129744b4db7e5 100644
--- a/compiler/rustc_next_trait_solver/src/solve/normalizes_to/mod.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/normalizes_to/mod.rs
@@ -6,7 +6,7 @@ mod weak_types;
 use rustc_type_ir::fast_reject::DeepRejectCtxt;
 use rustc_type_ir::inherent::*;
 use rustc_type_ir::lang_items::TraitSolverLangItem;
-use rustc_type_ir::{self as ty, Interner, NormalizesTo, Upcast as _};
+use rustc_type_ir::{self as ty, Interner, NormalizesTo, TypingMode, Upcast as _};
 use tracing::instrument;
 
 use crate::delegate::SolverDelegate;
@@ -15,7 +15,7 @@ use crate::solve::assembly::{self, Candidate};
 use crate::solve::inspect::ProbeKind;
 use crate::solve::{
     BuiltinImplSource, CandidateSource, Certainty, EvalCtxt, Goal, GoalSource, MaybeCause,
-    NoSolution, QueryResult, Reveal,
+    NoSolution, QueryResult,
 };
 
 impl<D, I> EvalCtxt<'_, D>
@@ -71,21 +71,21 @@ where
                 Ok(())
             }
             ty::AliasTermKind::OpaqueTy => {
-                match param_env.reveal() {
-                    // In user-facing mode, paques are only rigid if we may not define it.
-                    Reveal::UserFacing => {
+                match self.typing_mode(param_env) {
+                    // Opaques are never rigid outside of analysis mode.
+                    TypingMode::Coherence | TypingMode::PostAnalysis => Err(NoSolution),
+                    // During analysis, opaques are only rigid if we may not define it.
+                    TypingMode::Analysis { defining_opaque_types } => {
                         if rigid_alias
                             .def_id
                             .as_local()
-                            .is_some_and(|def_id| self.can_define_opaque_ty(def_id))
+                            .is_some_and(|def_id| defining_opaque_types.contains(&def_id))
                         {
                             Err(NoSolution)
                         } else {
                             Ok(())
                         }
                     }
-                    // Opaques are never rigid in reveal-all mode.
-                    Reveal::All => Err(NoSolution),
                 }
             }
             // FIXME(generic_const_exprs): we would need to support generic consts here
@@ -252,7 +252,6 @@ where
             // return ambiguity this would otherwise be incomplete, resulting in
             // unsoundness during coherence (#105782).
             let Some(target_item_def_id) = ecx.fetch_eligible_assoc_item(
-                goal.param_env,
                 goal_trait_ref,
                 goal.predicate.def_id(),
                 impl_def_id,
diff --git a/compiler/rustc_next_trait_solver/src/solve/normalizes_to/opaque_types.rs b/compiler/rustc_next_trait_solver/src/solve/normalizes_to/opaque_types.rs
index f8d51f304f332..d1d701695ab83 100644
--- a/compiler/rustc_next_trait_solver/src/solve/normalizes_to/opaque_types.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/normalizes_to/opaque_types.rs
@@ -4,12 +4,10 @@
 
 use rustc_index::bit_set::GrowableBitSet;
 use rustc_type_ir::inherent::*;
-use rustc_type_ir::{self as ty, Interner};
+use rustc_type_ir::{self as ty, Interner, TypingMode};
 
 use crate::delegate::SolverDelegate;
-use crate::solve::{
-    Certainty, EvalCtxt, Goal, NoSolution, QueryResult, Reveal, SolverMode, inspect,
-};
+use crate::solve::{Certainty, EvalCtxt, Goal, NoSolution, QueryResult, inspect};
 
 impl<D, I> EvalCtxt<'_, D>
 where
@@ -24,17 +22,27 @@ where
         let opaque_ty = goal.predicate.alias;
         let expected = goal.predicate.term.as_type().expect("no such thing as an opaque const");
 
-        match (goal.param_env.reveal(), self.solver_mode()) {
-            (Reveal::UserFacing, SolverMode::Normal) => {
-                let Some(opaque_ty_def_id) = opaque_ty.def_id.as_local() else {
+        match self.typing_mode(goal.param_env) {
+            TypingMode::Coherence => {
+                // An impossible opaque type bound is the only way this goal will fail
+                // e.g. assigning `impl Copy := NotCopy`
+                self.add_item_bounds_for_hidden_type(
+                    opaque_ty.def_id,
+                    opaque_ty.args,
+                    goal.param_env,
+                    expected,
+                );
+                self.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS)
+            }
+            TypingMode::Analysis { defining_opaque_types } => {
+                let Some(def_id) = opaque_ty.def_id.as_local() else {
                     return Err(NoSolution);
                 };
-                // FIXME: at some point we should call queries without defining
-                // new opaque types but having the existing opaque type definitions.
-                // This will require moving this below "Prefer opaques registered already".
-                if !self.can_define_opaque_ty(opaque_ty_def_id) {
+
+                if !defining_opaque_types.contains(&def_id) {
                     return Err(NoSolution);
                 }
+
                 // FIXME: This may have issues when the args contain aliases...
                 match uses_unique_placeholders_ignoring_regions(self.cx(), opaque_ty.args) {
                     Err(NotUniqueParam::NotParam(param)) if param.is_non_region_infer() => {
@@ -48,8 +56,7 @@ where
                     Ok(()) => {}
                 }
                 // Prefer opaques registered already.
-                let opaque_type_key =
-                    ty::OpaqueTypeKey { def_id: opaque_ty_def_id, args: opaque_ty.args };
+                let opaque_type_key = ty::OpaqueTypeKey { def_id, args: opaque_ty.args };
                 // FIXME: This also unifies the previous hidden type with the expected.
                 //
                 // If that fails, we insert `expected` as a new hidden type instead of
@@ -69,7 +76,7 @@ where
                             }
                             ecx.eq(goal.param_env, candidate_ty, expected)?;
                             ecx.add_item_bounds_for_hidden_type(
-                                candidate_key.def_id.into(),
+                                def_id.into(),
                                 candidate_key.args,
                                 goal.param_env,
                                 candidate_ty,
@@ -82,25 +89,14 @@ where
                 // FIXME: should we use `inject_hidden_type_unchecked` here?
                 self.insert_hidden_type(opaque_type_key, goal.param_env, expected)?;
                 self.add_item_bounds_for_hidden_type(
-                    opaque_ty.def_id,
+                    def_id.into(),
                     opaque_ty.args,
                     goal.param_env,
                     expected,
                 );
                 self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
             }
-            (Reveal::UserFacing, SolverMode::Coherence) => {
-                // An impossible opaque type bound is the only way this goal will fail
-                // e.g. assigning `impl Copy := NotCopy`
-                self.add_item_bounds_for_hidden_type(
-                    opaque_ty.def_id,
-                    opaque_ty.args,
-                    goal.param_env,
-                    expected,
-                );
-                self.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS)
-            }
-            (Reveal::All, _) => {
+            TypingMode::PostAnalysis => {
                 // FIXME: Add an assertion that opaque type storage is empty.
                 let actual = cx.type_of(opaque_ty.def_id).instantiate(cx, opaque_ty.args);
                 self.eq(goal.param_env, expected, actual)?;
diff --git a/compiler/rustc_next_trait_solver/src/solve/trait_goals.rs b/compiler/rustc_next_trait_solver/src/solve/trait_goals.rs
index 08cc89d950e22..e23e475a2a62a 100644
--- a/compiler/rustc_next_trait_solver/src/solve/trait_goals.rs
+++ b/compiler/rustc_next_trait_solver/src/solve/trait_goals.rs
@@ -6,7 +6,7 @@ use rustc_type_ir::fast_reject::DeepRejectCtxt;
 use rustc_type_ir::inherent::*;
 use rustc_type_ir::lang_items::TraitSolverLangItem;
 use rustc_type_ir::visit::TypeVisitableExt as _;
-use rustc_type_ir::{self as ty, Interner, TraitPredicate, Upcast as _, elaborate};
+use rustc_type_ir::{self as ty, Interner, TraitPredicate, TypingMode, Upcast as _, elaborate};
 use tracing::{instrument, trace};
 
 use crate::delegate::SolverDelegate;
@@ -15,7 +15,7 @@ use crate::solve::assembly::{self, Candidate};
 use crate::solve::inspect::ProbeKind;
 use crate::solve::{
     BuiltinImplSource, CandidateSource, Certainty, EvalCtxt, Goal, GoalSource, MaybeCause,
-    NoSolution, QueryResult, Reveal, SolverMode,
+    NoSolution, QueryResult,
 };
 
 impl<D, I> assembly::GoalKind<D> for TraitPredicate<I>
@@ -67,9 +67,9 @@ where
         let maximal_certainty = match (impl_polarity, goal.predicate.polarity) {
             // In intercrate mode, this is ambiguous. But outside of intercrate,
             // it's not a real impl.
-            (ty::ImplPolarity::Reservation, _) => match ecx.solver_mode() {
-                SolverMode::Coherence => Certainty::AMBIGUOUS,
-                SolverMode::Normal => return Err(NoSolution),
+            (ty::ImplPolarity::Reservation, _) => match ecx.typing_mode(goal.param_env) {
+                TypingMode::Coherence => Certainty::AMBIGUOUS,
+                TypingMode::Analysis { .. } | TypingMode::PostAnalysis => return Err(NoSolution),
             },
 
             // Impl matches polarity
@@ -167,30 +167,26 @@ where
             return result;
         }
 
-        // Don't call `type_of` on a local TAIT that's in the defining scope,
-        // since that may require calling `typeck` on the same item we're
+        // We only look into opaque types during analysis for opaque types
+        // outside of their defining scope. Doing so for opaques in the
+        // defining scope may require calling `typeck` on the same item we're
         // currently type checking, which will result in a fatal cycle that
         // ideally we want to avoid, since we can make progress on this goal
         // via an alias bound or a locally-inferred hidden type instead.
-        //
-        // Also, don't call `type_of` on a TAIT in `Reveal::All` mode, since
-        // we already normalize the self type in
-        // `assemble_candidates_after_normalizing_self_ty`, and we'd
-        // just be registering an identical candidate here.
-        //
-        // We always return `Err(NoSolution)` here in `SolverMode::Coherence`
-        // since we'll always register an ambiguous candidate in
-        // `assemble_candidates_after_normalizing_self_ty` due to normalizing
-        // the TAIT.
         if let ty::Alias(ty::Opaque, opaque_ty) = goal.predicate.self_ty().kind() {
-            if matches!(goal.param_env.reveal(), Reveal::All)
-                || matches!(ecx.solver_mode(), SolverMode::Coherence)
-                || opaque_ty
-                    .def_id
-                    .as_local()
-                    .is_some_and(|def_id| ecx.can_define_opaque_ty(def_id))
-            {
-                return Err(NoSolution);
+            match ecx.typing_mode(goal.param_env) {
+                TypingMode::Coherence | TypingMode::PostAnalysis => {
+                    unreachable!("rigid opaque outside of analysis: {goal:?}");
+                }
+                TypingMode::Analysis { defining_opaque_types } => {
+                    if opaque_ty
+                        .def_id
+                        .as_local()
+                        .is_some_and(|def_id| defining_opaque_types.contains(&def_id))
+                    {
+                        return Err(NoSolution);
+                    }
+                }
             }
         }
 
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index 77ad4fdeeb17b..50a8b6542df4f 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -424,7 +424,7 @@ impl TokenDescription {
     }
 }
 
-pub(super) fn token_descr(token: &Token) -> String {
+pub fn token_descr(token: &Token) -> String {
     let name = pprust::token_to_string(token).to_string();
 
     let kind = match (TokenDescription::from_token(token), &token.kind) {
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index 8c4592cbb369f..0a2926c040447 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -25,7 +25,7 @@ use rustc_middle::middle::resolve_bound_vars::ObjectLifetimeDefault;
 use rustc_middle::query::Providers;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::{self, TyCtxt};
+use rustc_middle::ty::{self, TyCtxt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint::builtin::{
     CONFLICTING_REPR_HINTS, INVALID_DOC_ATTRIBUTES, INVALID_MACRO_EXPORT_ARGUMENTS,
@@ -2267,7 +2267,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
         let def_id = hir_id.expect_owner().def_id;
         let param_env = ty::ParamEnv::empty();
 
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
         let span = tcx.def_span(def_id);
diff --git a/compiler/rustc_passes/src/layout_test.rs b/compiler/rustc_passes/src/layout_test.rs
index 0b6cf82ca8b46..986dce5b56dcf 100644
--- a/compiler/rustc_passes/src/layout_test.rs
+++ b/compiler/rustc_passes/src/layout_test.rs
@@ -2,6 +2,7 @@ use rustc_abi::{HasDataLayout, TargetDataLayout};
 use rustc_ast::Attribute;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LocalDefId;
+use rustc_middle::infer::canonical::ir::TypingMode;
 use rustc_middle::span_bug;
 use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers};
 use rustc_middle::ty::{self, ParamEnv, Ty, TyCtxt};
@@ -54,7 +55,7 @@ pub fn ensure_wf<'tcx>(
         param_env,
         pred,
     );
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
     let ocx = traits::ObligationCtxt::new_with_diagnostics(&infcx);
     ocx.register_obligation(obligation);
     let errors = ocx.select_all_or_error();
@@ -81,8 +82,12 @@ fn dump_layout_of(tcx: TyCtxt<'_>, item_def_id: LocalDefId, attr: &Attribute) {
             let meta_items = attr.meta_item_list().unwrap_or_default();
             for meta_item in meta_items {
                 match meta_item.name_or_empty() {
+                    // FIXME: this never was about ABI and now this dump arg is confusing
                     sym::abi => {
-                        tcx.dcx().emit_err(LayoutAbi { span, abi: format!("{:?}", ty_layout.abi) });
+                        tcx.dcx().emit_err(LayoutAbi {
+                            span,
+                            abi: format!("{:?}", ty_layout.backend_repr),
+                        });
                     }
 
                     sym::align => {
diff --git a/compiler/rustc_smir/src/rustc_smir/convert/abi.rs b/compiler/rustc_smir/src/rustc_smir/convert/abi.rs
index 410bf0f40f467..af24fd23f50b9 100644
--- a/compiler/rustc_smir/src/rustc_smir/convert/abi.rs
+++ b/compiler/rustc_smir/src/rustc_smir/convert/abi.rs
@@ -56,7 +56,7 @@ impl<'tcx> Stable<'tcx> for rustc_abi::LayoutData<rustc_abi::FieldIdx, rustc_abi
         LayoutShape {
             fields: self.fields.stable(tables),
             variants: self.variants.stable(tables),
-            abi: self.abi.stable(tables),
+            abi: self.backend_repr.stable(tables),
             abi_align: self.align.abi.stable(tables),
             size: self.size.stable(tables),
         }
@@ -196,20 +196,20 @@ impl<'tcx> Stable<'tcx> for rustc_abi::TagEncoding<rustc_abi::VariantIdx> {
     }
 }
 
-impl<'tcx> Stable<'tcx> for rustc_abi::Abi {
+impl<'tcx> Stable<'tcx> for rustc_abi::BackendRepr {
     type T = ValueAbi;
 
     fn stable(&self, tables: &mut Tables<'_>) -> Self::T {
         match *self {
-            rustc_abi::Abi::Uninhabited => ValueAbi::Uninhabited,
-            rustc_abi::Abi::Scalar(scalar) => ValueAbi::Scalar(scalar.stable(tables)),
-            rustc_abi::Abi::ScalarPair(first, second) => {
+            rustc_abi::BackendRepr::Uninhabited => ValueAbi::Uninhabited,
+            rustc_abi::BackendRepr::Scalar(scalar) => ValueAbi::Scalar(scalar.stable(tables)),
+            rustc_abi::BackendRepr::ScalarPair(first, second) => {
                 ValueAbi::ScalarPair(first.stable(tables), second.stable(tables))
             }
-            rustc_abi::Abi::Vector { element, count } => {
+            rustc_abi::BackendRepr::Vector { element, count } => {
                 ValueAbi::Vector { element: element.stable(tables), count }
             }
-            rustc_abi::Abi::Aggregate { sized } => ValueAbi::Aggregate { sized },
+            rustc_abi::BackendRepr::Memory { sized } => ValueAbi::Aggregate { sized },
         }
     }
 }
diff --git a/compiler/rustc_target/src/callconv/loongarch.rs b/compiler/rustc_target/src/callconv/loongarch.rs
index ffec76370d026..d1234c3cc91d4 100644
--- a/compiler/rustc_target/src/callconv/loongarch.rs
+++ b/compiler/rustc_target/src/callconv/loongarch.rs
@@ -1,5 +1,7 @@
 use crate::abi::call::{ArgAbi, ArgExtension, CastTarget, FnAbi, PassMode, Reg, RegKind, Uniform};
-use crate::abi::{self, Abi, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
+use crate::abi::{
+    self, BackendRepr, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout,
+};
 use crate::spec::HasTargetSpec;
 use crate::spec::abi::Abi as SpecAbi;
 
@@ -21,8 +23,8 @@ enum FloatConv {
 struct CannotUseFpConv;
 
 fn is_loongarch_aggregate<Ty>(arg: &ArgAbi<'_, Ty>) -> bool {
-    match arg.layout.abi {
-        Abi::Vector { .. } => true,
+    match arg.layout.backend_repr {
+        BackendRepr::Vector { .. } => true,
         _ => arg.layout.is_aggregate(),
     }
 }
@@ -38,8 +40,8 @@ fn should_use_fp_conv_helper<'a, Ty, C>(
 where
     Ty: TyAbiInterface<'a, C> + Copy,
 {
-    match arg_layout.abi {
-        Abi::Scalar(scalar) => match scalar.primitive() {
+    match arg_layout.backend_repr {
+        BackendRepr::Scalar(scalar) => match scalar.primitive() {
             abi::Int(..) | abi::Pointer(_) => {
                 if arg_layout.size.bits() > xlen {
                     return Err(CannotUseFpConv);
@@ -77,8 +79,8 @@ where
                 }
             }
         },
-        Abi::Vector { .. } | Abi::Uninhabited => return Err(CannotUseFpConv),
-        Abi::ScalarPair(..) | Abi::Aggregate { .. } => match arg_layout.fields {
+        BackendRepr::Vector { .. } | BackendRepr::Uninhabited => return Err(CannotUseFpConv),
+        BackendRepr::ScalarPair(..) | BackendRepr::Memory { .. } => match arg_layout.fields {
             FieldsShape::Primitive => {
                 unreachable!("aggregates can't have `FieldsShape::Primitive`")
             }
@@ -311,7 +313,7 @@ fn classify_arg<'a, Ty, C>(
 }
 
 fn extend_integer_width<Ty>(arg: &mut ArgAbi<'_, Ty>, xlen: u64) {
-    if let Abi::Scalar(scalar) = arg.layout.abi {
+    if let BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
         if let abi::Int(i, _) = scalar.primitive() {
             // 32-bit integers are always sign-extended
             if i.size().bits() == 32 && xlen > 32 {
diff --git a/compiler/rustc_target/src/callconv/mips64.rs b/compiler/rustc_target/src/callconv/mips64.rs
index 2c3258c8d42d4..5bdf4c2ad77f0 100644
--- a/compiler/rustc_target/src/callconv/mips64.rs
+++ b/compiler/rustc_target/src/callconv/mips64.rs
@@ -5,7 +5,7 @@ use crate::abi::{self, HasDataLayout, Size, TyAbiInterface};
 
 fn extend_integer_width_mips<Ty>(arg: &mut ArgAbi<'_, Ty>, bits: u64) {
     // Always sign extend u32 values on 64-bit mips
-    if let abi::Abi::Scalar(scalar) = arg.layout.abi {
+    if let abi::BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
         if let abi::Int(i, signed) = scalar.primitive() {
             if !signed && i.size().bits() == 32 {
                 if let PassMode::Direct(ref mut attrs) = arg.mode {
@@ -24,8 +24,8 @@ where
     Ty: TyAbiInterface<'a, C> + Copy,
     C: HasDataLayout,
 {
-    match ret.layout.field(cx, i).abi {
-        abi::Abi::Scalar(scalar) => match scalar.primitive() {
+    match ret.layout.field(cx, i).backend_repr {
+        abi::BackendRepr::Scalar(scalar) => match scalar.primitive() {
             abi::Float(abi::F32) => Some(Reg::f32()),
             abi::Float(abi::F64) => Some(Reg::f64()),
             _ => None,
@@ -109,7 +109,7 @@ where
                 let offset = arg.layout.fields.offset(i);
 
                 // We only care about aligned doubles
-                if let abi::Abi::Scalar(scalar) = field.abi {
+                if let abi::BackendRepr::Scalar(scalar) = field.backend_repr {
                     if scalar.primitive() == abi::Float(abi::F64) {
                         if offset.is_aligned(dl.f64_align.abi) {
                             // Insert enough integers to cover [last_offset, offset)
diff --git a/compiler/rustc_target/src/callconv/mod.rs b/compiler/rustc_target/src/callconv/mod.rs
index 25b001b57e8a8..8c3df9c426b0a 100644
--- a/compiler/rustc_target/src/callconv/mod.rs
+++ b/compiler/rustc_target/src/callconv/mod.rs
@@ -6,7 +6,8 @@ use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 
 use crate::abi::{
-    self, Abi, AddressSpace, Align, HasDataLayout, Pointer, Size, TyAbiInterface, TyAndLayout,
+    self, AddressSpace, Align, BackendRepr, HasDataLayout, Pointer, Size, TyAbiInterface,
+    TyAndLayout,
 };
 use crate::spec::abi::Abi as SpecAbi;
 use crate::spec::{self, HasTargetSpec, HasWasmCAbiOpt, HasX86AbiOpt, WasmCAbi};
@@ -350,15 +351,17 @@ impl<'a, Ty> ArgAbi<'a, Ty> {
         layout: TyAndLayout<'a, Ty>,
         scalar_attrs: impl Fn(&TyAndLayout<'a, Ty>, abi::Scalar, Size) -> ArgAttributes,
     ) -> Self {
-        let mode = match layout.abi {
-            Abi::Uninhabited => PassMode::Ignore,
-            Abi::Scalar(scalar) => PassMode::Direct(scalar_attrs(&layout, scalar, Size::ZERO)),
-            Abi::ScalarPair(a, b) => PassMode::Pair(
+        let mode = match layout.backend_repr {
+            BackendRepr::Uninhabited => PassMode::Ignore,
+            BackendRepr::Scalar(scalar) => {
+                PassMode::Direct(scalar_attrs(&layout, scalar, Size::ZERO))
+            }
+            BackendRepr::ScalarPair(a, b) => PassMode::Pair(
                 scalar_attrs(&layout, a, Size::ZERO),
                 scalar_attrs(&layout, b, a.size(cx).align_to(b.align(cx).abi)),
             ),
-            Abi::Vector { .. } => PassMode::Direct(ArgAttributes::new()),
-            Abi::Aggregate { .. } => Self::indirect_pass_mode(&layout),
+            BackendRepr::Vector { .. } => PassMode::Direct(ArgAttributes::new()),
+            BackendRepr::Memory { .. } => Self::indirect_pass_mode(&layout),
         };
         ArgAbi { layout, mode }
     }
@@ -460,7 +463,7 @@ impl<'a, Ty> ArgAbi<'a, Ty> {
 
     pub fn extend_integer_width_to(&mut self, bits: u64) {
         // Only integers have signedness
-        if let Abi::Scalar(scalar) = self.layout.abi {
+        if let BackendRepr::Scalar(scalar) = self.layout.backend_repr {
             if let abi::Int(i, signed) = scalar.primitive() {
                 if i.size().bits() < bits {
                     if let PassMode::Direct(ref mut attrs) = self.mode {
@@ -512,7 +515,7 @@ impl<'a, Ty> ArgAbi<'a, Ty> {
             // That elevates any type difference to an ABI difference since we just use the
             // full Rust type as the LLVM argument/return type.
             if matches!(self.mode, PassMode::Direct(..))
-                && matches!(self.layout.abi, Abi::Aggregate { .. })
+                && matches!(self.layout.backend_repr, BackendRepr::Memory { .. })
             {
                 // For aggregates in `Direct` mode to be compatible, the types need to be equal.
                 self.layout.ty == other.layout.ty
@@ -791,8 +794,8 @@ impl<'a, Ty> FnAbi<'a, Ty> {
                 continue;
             }
 
-            match arg.layout.abi {
-                Abi::Aggregate { .. } => {}
+            match arg.layout.backend_repr {
+                BackendRepr::Memory { .. } => {}
 
                 // This is a fun case! The gist of what this is doing is
                 // that we want callers and callees to always agree on the
@@ -813,7 +816,9 @@ impl<'a, Ty> FnAbi<'a, Ty> {
                 // Note that the intrinsic ABI is exempt here as
                 // that's how we connect up to LLVM and it's unstable
                 // anyway, we control all calls to it in libstd.
-                Abi::Vector { .. } if abi != SpecAbi::RustIntrinsic && spec.simd_types_indirect => {
+                BackendRepr::Vector { .. }
+                    if abi != SpecAbi::RustIntrinsic && spec.simd_types_indirect =>
+                {
                     arg.make_indirect();
                     continue;
                 }
diff --git a/compiler/rustc_target/src/callconv/riscv.rs b/compiler/rustc_target/src/callconv/riscv.rs
index f96169e6a618f..c0298edb5ab77 100644
--- a/compiler/rustc_target/src/callconv/riscv.rs
+++ b/compiler/rustc_target/src/callconv/riscv.rs
@@ -4,8 +4,10 @@
 // Reference: Clang RISC-V ELF psABI lowering code
 // https://github.com/llvm/llvm-project/blob/8e780252a7284be45cf1ba224cabd884847e8e92/clang/lib/CodeGen/TargetInfo.cpp#L9311-L9773
 
+use rustc_abi::{BackendRepr, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
+
+use crate::abi;
 use crate::abi::call::{ArgAbi, ArgExtension, CastTarget, FnAbi, PassMode, Reg, RegKind, Uniform};
-use crate::abi::{self, Abi, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
 use crate::spec::HasTargetSpec;
 use crate::spec::abi::Abi as SpecAbi;
 
@@ -27,8 +29,8 @@ enum FloatConv {
 struct CannotUseFpConv;
 
 fn is_riscv_aggregate<Ty>(arg: &ArgAbi<'_, Ty>) -> bool {
-    match arg.layout.abi {
-        Abi::Vector { .. } => true,
+    match arg.layout.backend_repr {
+        BackendRepr::Vector { .. } => true,
         _ => arg.layout.is_aggregate(),
     }
 }
@@ -44,8 +46,8 @@ fn should_use_fp_conv_helper<'a, Ty, C>(
 where
     Ty: TyAbiInterface<'a, C> + Copy,
 {
-    match arg_layout.abi {
-        Abi::Scalar(scalar) => match scalar.primitive() {
+    match arg_layout.backend_repr {
+        BackendRepr::Scalar(scalar) => match scalar.primitive() {
             abi::Int(..) | abi::Pointer(_) => {
                 if arg_layout.size.bits() > xlen {
                     return Err(CannotUseFpConv);
@@ -83,8 +85,8 @@ where
                 }
             }
         },
-        Abi::Vector { .. } | Abi::Uninhabited => return Err(CannotUseFpConv),
-        Abi::ScalarPair(..) | Abi::Aggregate { .. } => match arg_layout.fields {
+        BackendRepr::Vector { .. } | BackendRepr::Uninhabited => return Err(CannotUseFpConv),
+        BackendRepr::ScalarPair(..) | BackendRepr::Memory { .. } => match arg_layout.fields {
             FieldsShape::Primitive => {
                 unreachable!("aggregates can't have `FieldsShape::Primitive`")
             }
@@ -317,7 +319,7 @@ fn classify_arg<'a, Ty, C>(
 }
 
 fn extend_integer_width<Ty>(arg: &mut ArgAbi<'_, Ty>, xlen: u64) {
-    if let Abi::Scalar(scalar) = arg.layout.abi {
+    if let BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
         if let abi::Int(i, _) = scalar.primitive() {
             // 32-bit integers are always sign-extended
             if i.size().bits() == 32 && xlen > 32 {
diff --git a/compiler/rustc_target/src/callconv/sparc64.rs b/compiler/rustc_target/src/callconv/sparc64.rs
index 835353f76fc9a..313d8730399b2 100644
--- a/compiler/rustc_target/src/callconv/sparc64.rs
+++ b/compiler/rustc_target/src/callconv/sparc64.rs
@@ -109,11 +109,11 @@ where
         return data;
     }
 
-    match layout.abi {
-        abi::Abi::Scalar(scalar) => {
+    match layout.backend_repr {
+        abi::BackendRepr::Scalar(scalar) => {
             data = arg_scalar(cx, &scalar, offset, data);
         }
-        abi::Abi::Aggregate { .. } => {
+        abi::BackendRepr::Memory { .. } => {
             for i in 0..layout.fields.count() {
                 if offset < layout.fields.offset(i) {
                     offset = layout.fields.offset(i);
@@ -122,7 +122,7 @@ where
             }
         }
         _ => {
-            if let abi::Abi::ScalarPair(scalar1, scalar2) = &layout.abi {
+            if let abi::BackendRepr::ScalarPair(scalar1, scalar2) = &layout.backend_repr {
                 data = arg_scalar_pair(cx, scalar1, scalar2, offset, data);
             }
         }
diff --git a/compiler/rustc_target/src/callconv/x86.rs b/compiler/rustc_target/src/callconv/x86.rs
index e907beecb381a..a5af975d4d24d 100644
--- a/compiler/rustc_target/src/callconv/x86.rs
+++ b/compiler/rustc_target/src/callconv/x86.rs
@@ -1,6 +1,6 @@
 use crate::abi::call::{ArgAttribute, FnAbi, PassMode, Reg, RegKind};
 use crate::abi::{
-    Abi, AddressSpace, Align, Float, HasDataLayout, Pointer, TyAbiInterface, TyAndLayout,
+    AddressSpace, Align, BackendRepr, Float, HasDataLayout, Pointer, TyAbiInterface, TyAndLayout,
 };
 use crate::spec::HasTargetSpec;
 use crate::spec::abi::Abi as SpecAbi;
@@ -105,10 +105,12 @@ where
             where
                 Ty: TyAbiInterface<'a, C> + Copy,
             {
-                match layout.abi {
-                    Abi::Uninhabited | Abi::Scalar(_) | Abi::ScalarPair(..) => false,
-                    Abi::Vector { .. } => true,
-                    Abi::Aggregate { .. } => {
+                match layout.backend_repr {
+                    BackendRepr::Uninhabited
+                    | BackendRepr::Scalar(_)
+                    | BackendRepr::ScalarPair(..) => false,
+                    BackendRepr::Vector { .. } => true,
+                    BackendRepr::Memory { .. } => {
                         for i in 0..layout.fields.count() {
                             if contains_vector(cx, layout.field(cx, i)) {
                                 return true;
@@ -223,9 +225,9 @@ where
         // Intrinsics themselves are not actual "real" functions, so theres no need to change their ABIs.
         && abi != SpecAbi::RustIntrinsic
     {
-        let has_float = match fn_abi.ret.layout.abi {
-            Abi::Scalar(s) => matches!(s.primitive(), Float(_)),
-            Abi::ScalarPair(s1, s2) => {
+        let has_float = match fn_abi.ret.layout.backend_repr {
+            BackendRepr::Scalar(s) => matches!(s.primitive(), Float(_)),
+            BackendRepr::ScalarPair(s1, s2) => {
                 matches!(s1.primitive(), Float(_)) || matches!(s2.primitive(), Float(_))
             }
             _ => false, // anyway not passed via registers on x86
diff --git a/compiler/rustc_target/src/callconv/x86_64.rs b/compiler/rustc_target/src/callconv/x86_64.rs
index 9910e623ac9b5..bd101b23ea16b 100644
--- a/compiler/rustc_target/src/callconv/x86_64.rs
+++ b/compiler/rustc_target/src/callconv/x86_64.rs
@@ -1,8 +1,10 @@
 // The classification code for the x86_64 ABI is taken from the clay language
 // https://github.com/jckarter/clay/blob/db0bd2702ab0b6e48965cd85f8859bbd5f60e48e/compiler/externals.cpp
 
+use rustc_abi::{BackendRepr, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
+
+use crate::abi;
 use crate::abi::call::{ArgAbi, CastTarget, FnAbi, Reg, RegKind};
-use crate::abi::{self, Abi, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
 
 /// Classification of "eightbyte" components.
 // N.B., the order of the variants is from general to specific,
@@ -46,17 +48,17 @@ where
             return Ok(());
         }
 
-        let mut c = match layout.abi {
-            Abi::Uninhabited => return Ok(()),
+        let mut c = match layout.backend_repr {
+            BackendRepr::Uninhabited => return Ok(()),
 
-            Abi::Scalar(scalar) => match scalar.primitive() {
+            BackendRepr::Scalar(scalar) => match scalar.primitive() {
                 abi::Int(..) | abi::Pointer(_) => Class::Int,
                 abi::Float(_) => Class::Sse,
             },
 
-            Abi::Vector { .. } => Class::Sse,
+            BackendRepr::Vector { .. } => Class::Sse,
 
-            Abi::ScalarPair(..) | Abi::Aggregate { .. } => {
+            BackendRepr::ScalarPair(..) | BackendRepr::Memory { .. } => {
                 for i in 0..layout.fields.count() {
                     let field_off = off + layout.fields.offset(i);
                     classify(cx, layout.field(cx, i), cls, field_off)?;
diff --git a/compiler/rustc_target/src/callconv/x86_win64.rs b/compiler/rustc_target/src/callconv/x86_win64.rs
index e5a20b248e43b..83d94cb11bafd 100644
--- a/compiler/rustc_target/src/callconv/x86_win64.rs
+++ b/compiler/rustc_target/src/callconv/x86_win64.rs
@@ -1,25 +1,28 @@
+use rustc_abi::{BackendRepr, Float, Primitive};
+
 use crate::abi::call::{ArgAbi, FnAbi, Reg};
-use crate::abi::{Abi, Float, Primitive};
 use crate::spec::HasTargetSpec;
 
 // Win64 ABI: https://docs.microsoft.com/en-us/cpp/build/parameter-passing
 
 pub(crate) fn compute_abi_info<Ty>(cx: &impl HasTargetSpec, fn_abi: &mut FnAbi<'_, Ty>) {
     let fixup = |a: &mut ArgAbi<'_, Ty>| {
-        match a.layout.abi {
-            Abi::Uninhabited | Abi::Aggregate { sized: false } => {}
-            Abi::ScalarPair(..) | Abi::Aggregate { sized: true } => match a.layout.size.bits() {
-                8 => a.cast_to(Reg::i8()),
-                16 => a.cast_to(Reg::i16()),
-                32 => a.cast_to(Reg::i32()),
-                64 => a.cast_to(Reg::i64()),
-                _ => a.make_indirect(),
-            },
-            Abi::Vector { .. } => {
+        match a.layout.backend_repr {
+            BackendRepr::Uninhabited | BackendRepr::Memory { sized: false } => {}
+            BackendRepr::ScalarPair(..) | BackendRepr::Memory { sized: true } => {
+                match a.layout.size.bits() {
+                    8 => a.cast_to(Reg::i8()),
+                    16 => a.cast_to(Reg::i16()),
+                    32 => a.cast_to(Reg::i32()),
+                    64 => a.cast_to(Reg::i64()),
+                    _ => a.make_indirect(),
+                }
+            }
+            BackendRepr::Vector { .. } => {
                 // FIXME(eddyb) there should be a size cap here
                 // (probably what clang calls "illegal vectors").
             }
-            Abi::Scalar(scalar) => {
+            BackendRepr::Scalar(scalar) => {
                 // Match what LLVM does for `f128` so that `compiler-builtins` builtins match up
                 // with what LLVM expects.
                 if a.layout.size.bytes() > 8
diff --git a/compiler/rustc_target/src/callconv/xtensa.rs b/compiler/rustc_target/src/callconv/xtensa.rs
index e1728b08a396b..9d313d1650032 100644
--- a/compiler/rustc_target/src/callconv/xtensa.rs
+++ b/compiler/rustc_target/src/callconv/xtensa.rs
@@ -6,7 +6,7 @@
 //! Section 2.3 from the Xtensa programmers guide.
 
 use crate::abi::call::{ArgAbi, FnAbi, Reg, Uniform};
-use crate::abi::{Abi, HasDataLayout, Size, TyAbiInterface};
+use crate::abi::{BackendRepr, HasDataLayout, Size, TyAbiInterface};
 use crate::spec::HasTargetSpec;
 
 const NUM_ARG_GPRS: u64 = 6;
@@ -114,8 +114,8 @@ where
 }
 
 fn is_xtensa_aggregate<'a, Ty>(arg: &ArgAbi<'a, Ty>) -> bool {
-    match arg.layout.abi {
-        Abi::Vector { .. } => true,
+    match arg.layout.backend_repr {
+        BackendRepr::Vector { .. } => true,
         _ => arg.layout.is_aggregate(),
     }
 }
diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs
index 5793ac2fc313c..c53689b211d2a 100644
--- a/compiler/rustc_trait_selection/src/solve/delegate.rs
+++ b/compiler/rustc_trait_selection/src/solve/delegate.rs
@@ -7,13 +7,13 @@ use rustc_infer::infer::canonical::{
     Canonical, CanonicalExt as _, CanonicalQueryInput, CanonicalVarInfo, CanonicalVarValues,
 };
 use rustc_infer::infer::{InferCtxt, RegionVariableOrigin, TyCtxtInferExt};
+use rustc_infer::traits::ObligationCause;
 use rustc_infer::traits::solve::Goal;
-use rustc_infer::traits::{ObligationCause, Reveal};
 use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt as _};
 use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span};
-use rustc_type_ir::solve::{Certainty, NoSolution, SolverMode};
-use tracing::trace;
+use rustc_type_ir::TypingMode;
+use rustc_type_ir::solve::{Certainty, NoSolution};
 
 use crate::traits::specialization_graph;
 
@@ -47,7 +47,6 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate<
 
     fn build_with_canonical<V>(
         interner: TyCtxt<'tcx>,
-        solver_mode: SolverMode,
         canonical: &CanonicalQueryInput<'tcx, V>,
     ) -> (Self, V, CanonicalVarValues<'tcx>)
     where
@@ -56,10 +55,6 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate<
         let (infcx, value, vars) = interner
             .infer_ctxt()
             .with_next_trait_solver(true)
-            .intercrate(match solver_mode {
-                SolverMode::Normal => false,
-                SolverMode::Coherence => true,
-            })
             .build_with_canonical(DUMMY_SP, canonical);
         (SolverDelegate(infcx), value, vars)
     }
@@ -195,7 +190,6 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate<
 
     fn fetch_eligible_assoc_item(
         &self,
-        param_env: ty::ParamEnv<'tcx>,
         goal_trait_ref: ty::TraitRef<'tcx>,
         trait_assoc_def_id: DefId,
         impl_def_id: DefId,
@@ -211,12 +205,12 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate<
             // and the obligation is monomorphic, otherwise passes such as
             // transmute checking and polymorphic MIR optimizations could
             // get a result which isn't correct for all monomorphizations.
-            if param_env.reveal() == Reveal::All {
-                let poly_trait_ref = self.resolve_vars_if_possible(goal_trait_ref);
-                !poly_trait_ref.still_further_specializable()
-            } else {
-                trace!(?node_item.item.def_id, "not eligible due to default");
-                false
+            match self.typing_mode_unchecked() {
+                TypingMode::Coherence | TypingMode::Analysis { .. } => false,
+                TypingMode::PostAnalysis => {
+                    let poly_trait_ref = self.resolve_vars_if_possible(goal_trait_ref);
+                    !poly_trait_ref.still_further_specializable()
+                }
             }
         };
 
diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
index 934fe9ec47c0e..52ba5621d3191 100644
--- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs
+++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
@@ -10,6 +10,7 @@ use rustc_infer::infer::DefineOpaqueTypes;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::ty::{Region, RegionVid};
 use tracing::debug;
+use ty::TypingMode;
 
 use super::*;
 use crate::errors::UnableToConstructConstantValue;
@@ -79,7 +80,7 @@ impl<'tcx> AutoTraitFinder<'tcx> {
 
         let trait_ref = ty::TraitRef::new(tcx, trait_did, [ty]);
 
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let mut selcx = SelectionContext::new(&infcx);
         for polarity in [ty::PredicatePolarity::Positive, ty::PredicatePolarity::Negative] {
             let result = selcx.select(&Obligation::new(
@@ -99,7 +100,7 @@ impl<'tcx> AutoTraitFinder<'tcx> {
             }
         }
 
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let mut fresh_preds = FxIndexSet::default();
 
         // Due to the way projections are handled by SelectionContext, we need to run
diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs
index f8fb297e36c4b..3cd11d7c8e8de 100644
--- a/compiler/rustc_trait_selection/src/traits/coherence.rs
+++ b/compiler/rustc_trait_selection/src/traits/coherence.rs
@@ -18,7 +18,7 @@ use rustc_middle::traits::solve::{CandidateSource, Certainty, Goal};
 use rustc_middle::traits::specialization_graph::OverlapMode;
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
 use rustc_middle::ty::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor};
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypingMode};
 pub use rustc_next_trait_solver::coherence::*;
 use rustc_next_trait_solver::solve::SolverDelegateEvalExt;
 use rustc_span::symbol::sym;
@@ -195,9 +195,8 @@ fn overlap<'tcx>(
     let infcx = tcx
         .infer_ctxt()
         .skip_leak_check(skip_leak_check.is_yes())
-        .intercrate(true)
         .with_next_trait_solver(tcx.next_trait_solver_in_coherence())
-        .build();
+        .build(TypingMode::Coherence);
     let selcx = &mut SelectionContext::new(&infcx);
     if track_ambiguity_causes.is_yes() {
         selcx.enable_tracking_intercrate_ambiguity_causes();
@@ -419,7 +418,7 @@ fn impl_intersection_has_negative_obligation(
 
     // N.B. We need to unify impl headers *with* intercrate mode, even if proving negative predicates
     // do not need intercrate mode enabled.
-    let ref infcx = tcx.infer_ctxt().intercrate(true).with_next_trait_solver(true).build();
+    let ref infcx = tcx.infer_ctxt().with_next_trait_solver(true).build(TypingMode::Coherence);
     let root_universe = infcx.universe();
     assert_eq!(root_universe, ty::UniverseIndex::ROOT);
 
@@ -570,7 +569,9 @@ fn try_prove_negated_where_clause<'tcx>(
     // the *existence* of a negative goal, not the non-existence of a positive goal.
     // Without this, we over-eagerly register coherence ambiguity candidates when
     // impl candidates do exist.
-    let ref infcx = root_infcx.fork_with_intercrate(false);
+    // FIXME(#132279): `TypingMode::non_body_analysis` is a bit questionable here as it
+    // would cause us to reveal opaque types to leak their auto traits.
+    let ref infcx = root_infcx.fork_with_typing_mode(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new(infcx);
     ocx.register_obligation(Obligation::new(
         infcx.tcx,
@@ -714,7 +715,10 @@ impl<'a, 'tcx> ProofTreeVisitor<'tcx> for AmbiguityCausesVisitor<'a, 'tcx> {
 
             // It is only relevant that a goal is unknowable if it would have otherwise
             // failed.
-            let non_intercrate_infcx = infcx.fork_with_intercrate(false);
+            // FIXME(#132279): Forking with `TypingMode::non_body_analysis` is a bit questionable
+            // as it would allow us to reveal opaque types, potentially causing unexpected
+            // cycles.
+            let non_intercrate_infcx = infcx.fork_with_typing_mode(TypingMode::non_body_analysis());
             if non_intercrate_infcx.predicate_may_hold(&Obligation::new(
                 infcx.tcx,
                 ObligationCause::dummy(),
diff --git a/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs b/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs
index a068f25fe35ec..0eaacbcfbea64 100644
--- a/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs
+++ b/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs
@@ -14,11 +14,11 @@ use rustc_middle::query::Providers;
 use rustc_middle::ty::{
     self, EarlyBinder, ExistentialPredicateStableCmpExt as _, GenericArgs, Ty, TyCtxt,
     TypeFoldable, TypeFolder, TypeSuperFoldable, TypeSuperVisitable, TypeVisitable,
-    TypeVisitableExt, TypeVisitor, Upcast,
+    TypeVisitableExt, TypeVisitor, TypingMode, Upcast,
 };
 use rustc_span::Span;
 use rustc_span::symbol::Symbol;
-use rustc_target::abi::Abi;
+use rustc_target::abi::BackendRepr;
 use smallvec::SmallVec;
 use tracing::{debug, instrument};
 
@@ -523,8 +523,8 @@ fn check_receiver_correct<'tcx>(tcx: TyCtxt<'tcx>, trait_def_id: DefId, method:
 
     // e.g., `Rc<()>`
     let unit_receiver_ty = receiver_for_self_ty(tcx, receiver_ty, tcx.types.unit, method_def_id);
-    match tcx.layout_of(param_env.and(unit_receiver_ty)).map(|l| l.abi) {
-        Ok(Abi::Scalar(..)) => (),
+    match tcx.layout_of(param_env.and(unit_receiver_ty)).map(|l| l.backend_repr) {
+        Ok(BackendRepr::Scalar(..)) => (),
         abi => {
             tcx.dcx().span_delayed_bug(
                 tcx.def_span(method_def_id),
@@ -538,8 +538,8 @@ fn check_receiver_correct<'tcx>(tcx: TyCtxt<'tcx>, trait_def_id: DefId, method:
     // e.g., `Rc<dyn Trait>`
     let trait_object_receiver =
         receiver_for_self_ty(tcx, receiver_ty, trait_object_ty, method_def_id);
-    match tcx.layout_of(param_env.and(trait_object_receiver)).map(|l| l.abi) {
-        Ok(Abi::ScalarPair(..)) => (),
+    match tcx.layout_of(param_env.and(trait_object_receiver)).map(|l| l.backend_repr) {
+        Ok(BackendRepr::ScalarPair(..)) => (),
         abi => {
             tcx.dcx().span_delayed_bug(
                 tcx.def_span(method_def_id),
@@ -718,7 +718,7 @@ fn receiver_is_dispatchable<'tcx>(
         Obligation::new(tcx, ObligationCause::dummy(), param_env, predicate)
     };
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     // the receiver is dispatchable iff the obligation holds
     infcx.predicate_must_hold_modulo_regions(&obligation)
 }
diff --git a/compiler/rustc_trait_selection/src/traits/effects.rs b/compiler/rustc_trait_selection/src/traits/effects.rs
index bd8c04b765570..60b3357810a65 100644
--- a/compiler/rustc_trait_selection/src/traits/effects.rs
+++ b/compiler/rustc_trait_selection/src/traits/effects.rs
@@ -1,8 +1,9 @@
 use rustc_hir as hir;
 use rustc_infer::infer::{BoundRegionConversionTime, DefineOpaqueTypes, InferCtxt};
 use rustc_infer::traits::{ImplSource, Obligation, PredicateObligation};
+use rustc_middle::span_bug;
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
-use rustc_middle::{span_bug, ty};
+use rustc_middle::ty::{self, TypingMode};
 use rustc_type_ir::solve::NoSolution;
 use thin_vec::ThinVec;
 
@@ -19,7 +20,7 @@ pub fn evaluate_host_effect_obligation<'tcx>(
     selcx: &mut SelectionContext<'_, 'tcx>,
     obligation: &HostEffectObligation<'tcx>,
 ) -> Result<ThinVec<PredicateObligation<'tcx>>, EvaluationFailure> {
-    if selcx.infcx.intercrate {
+    if matches!(selcx.infcx.typing_mode(obligation.param_env), TypingMode::Coherence) {
         span_bug!(
             obligation.cause.span,
             "should not select host obligation in old solver in intercrate mode"
diff --git a/compiler/rustc_trait_selection/src/traits/fulfill.rs b/compiler/rustc_trait_selection/src/traits/fulfill.rs
index e3ad21e352a06..29e60e3c428bc 100644
--- a/compiler/rustc_trait_selection/src/traits/fulfill.rs
+++ b/compiler/rustc_trait_selection/src/traits/fulfill.rs
@@ -13,7 +13,7 @@ use rustc_middle::bug;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::ty::abstract_const::NotConstEvaluatable;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::{self, Binder, Const, GenericArgsRef, TypeVisitableExt};
+use rustc_middle::ty::{self, Binder, Const, GenericArgsRef, TypeVisitableExt, TypingMode};
 use thin_vec::ThinVec;
 use tracing::{debug, debug_span, instrument};
 
@@ -760,7 +760,9 @@ impl<'a, 'tcx> FulfillProcessor<'a, 'tcx> {
         stalled_on: &mut Vec<TyOrConstInferVar>,
     ) -> ProcessResult<PendingPredicateObligation<'tcx>, FulfillmentErrorCode<'tcx>> {
         let infcx = self.selcx.infcx;
-        if obligation.predicate.is_global() && !self.selcx.is_intercrate() {
+        if obligation.predicate.is_global()
+            && !matches!(infcx.typing_mode(obligation.param_env), TypingMode::Coherence)
+        {
             // no type variables present, can use evaluation for better caching.
             // FIXME: consider caching errors too.
             if infcx.predicate_must_hold_considering_regions(obligation) {
@@ -813,11 +815,13 @@ impl<'a, 'tcx> FulfillProcessor<'a, 'tcx> {
         stalled_on: &mut Vec<TyOrConstInferVar>,
     ) -> ProcessResult<PendingPredicateObligation<'tcx>, FulfillmentErrorCode<'tcx>> {
         let tcx = self.selcx.tcx();
-
-        if obligation.predicate.is_global() && !self.selcx.is_intercrate() {
+        let infcx = self.selcx.infcx;
+        if obligation.predicate.is_global()
+            && !matches!(infcx.typing_mode(obligation.param_env), TypingMode::Coherence)
+        {
             // no type variables present, can use evaluation for better caching.
             // FIXME: consider caching errors too.
-            if self.selcx.infcx.predicate_must_hold_considering_regions(obligation) {
+            if infcx.predicate_must_hold_considering_regions(obligation) {
                 if let Some(key) = ProjectionCacheKey::from_poly_projection_obligation(
                     &mut self.selcx,
                     &project_obligation,
@@ -825,8 +829,7 @@ impl<'a, 'tcx> FulfillProcessor<'a, 'tcx> {
                     // If `predicate_must_hold_considering_regions` succeeds, then we've
                     // evaluated all sub-obligations. We can therefore mark the 'root'
                     // obligation as complete, and skip evaluating sub-obligations.
-                    self.selcx
-                        .infcx
+                    infcx
                         .inner
                         .borrow_mut()
                         .projection_cache()
diff --git a/compiler/rustc_trait_selection/src/traits/misc.rs b/compiler/rustc_trait_selection/src/traits/misc.rs
index 3e65194577e0d..3b17fa6b03285 100644
--- a/compiler/rustc_trait_selection/src/traits/misc.rs
+++ b/compiler/rustc_trait_selection/src/traits/misc.rs
@@ -8,7 +8,7 @@ use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir as hir;
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{RegionResolutionError, TyCtxtInferExt};
-use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt, TypeVisitableExt, TypingMode};
 
 use super::outlives_bounds::InferCtxtExt;
 use crate::regions::InferCtxtRegionExt;
@@ -143,7 +143,7 @@ pub fn type_allowed_to_implement_const_param_ty<'tcx>(
     let mut infringing_inner_tys = vec![];
     for inner_ty in inner_tys {
         // We use an ocx per inner ty for better diagnostics
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         let ocx = traits::ObligationCtxt::new_with_diagnostics(&infcx);
 
         ocx.register_bound(
@@ -200,7 +200,7 @@ pub fn all_fields_implement_trait<'tcx>(
     for variant in adt.variants() {
         for field in &variant.fields {
             // Do this per-field to get better error messages.
-            let infcx = tcx.infer_ctxt().build();
+            let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
             let ocx = traits::ObligationCtxt::new_with_diagnostics(&infcx);
 
             let unnormalized_ty = field.ty(tcx, args);
diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs
index f5d9b50359c13..1c84f2171bcac 100644
--- a/compiler/rustc_trait_selection/src/traits/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/mod.rs
@@ -34,7 +34,8 @@ use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::visit::{TypeVisitable, TypeVisitableExt};
 use rustc_middle::ty::{
-    self, GenericArgs, GenericArgsRef, Ty, TyCtxt, TypeFolder, TypeSuperVisitable, Upcast,
+    self, GenericArgs, GenericArgsRef, Ty, TyCtxt, TypeFolder, TypeSuperVisitable, TypingMode,
+    Upcast,
 };
 use rustc_span::Span;
 use rustc_span::def_id::DefId;
@@ -274,7 +275,7 @@ fn do_normalize_predicates<'tcx>(
     // by wfcheck anyway, so I'm not sure we have to check
     // them here too, and we will remove this function when
     // we move over to lazy normalization *anyway*.
-    let infcx = tcx.infer_ctxt().ignoring_regions().build();
+    let infcx = tcx.infer_ctxt().ignoring_regions().build(TypingMode::non_body_analysis());
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
     let predicates = ocx.normalize(&cause, elaborated_env, predicates);
 
@@ -475,11 +476,11 @@ pub fn normalize_param_env_or_error<'tcx>(
 
 /// Normalizes the predicates and checks whether they hold in an empty environment. If this
 /// returns true, then either normalize encountered an error or one of the predicates did not
-/// hold. Used when creating vtables to check for unsatisfiable methods.
+/// hold. Used when creating vtables to check for unsatisfiable methods. This should not be
+/// used during analysis.
 pub fn impossible_predicates<'tcx>(tcx: TyCtxt<'tcx>, predicates: Vec<ty::Clause<'tcx>>) -> bool {
     debug!("impossible_predicates(predicates={:?})", predicates);
-
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::PostAnalysis);
     let param_env = ty::ParamEnv::reveal_all();
     let ocx = ObligationCtxt::new(&infcx);
     let predicates = ocx.normalize(&ObligationCause::dummy(), param_env, predicates);
@@ -568,8 +569,11 @@ fn is_impossible_associated_item(
     // since that method *may* have some substitutions where the predicates hold.
     //
     // This replicates the logic we use in coherence.
-    let infcx =
-        tcx.infer_ctxt().ignoring_regions().with_next_trait_solver(true).intercrate(true).build();
+    let infcx = tcx
+        .infer_ctxt()
+        .ignoring_regions()
+        .with_next_trait_solver(true)
+        .build(TypingMode::Coherence);
     let param_env = ty::ParamEnv::empty();
     let fresh_args = infcx.fresh_args_for_item(tcx.def_span(impl_def_id), impl_def_id);
 
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 0803dd74b89bb..a75c07c2e8c6e 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -334,11 +334,6 @@ pub(super) fn opt_normalize_projection_term<'a, 'b, 'tcx>(
 ) -> Result<Option<Term<'tcx>>, InProgress> {
     let infcx = selcx.infcx;
     debug_assert!(!selcx.infcx.next_trait_solver());
-    // Don't use the projection cache in intercrate mode -
-    // the `infcx` may be re-used between intercrate in non-intercrate
-    // mode, which could lead to using incorrect cache results.
-    let use_cache = !selcx.is_intercrate();
-
     let projection_term = infcx.resolve_vars_if_possible(projection_term);
     let cache_key = ProjectionCacheKey::new(projection_term, param_env);
 
@@ -349,13 +344,8 @@ pub(super) fn opt_normalize_projection_term<'a, 'b, 'tcx>(
     // would not benefit from caching when proving `T: Trait<U=Foo>`
     // bounds. It might be the case that we want two distinct caches,
     // or else another kind of cache entry.
-
-    let cache_result = if use_cache {
-        infcx.inner.borrow_mut().projection_cache().try_start(cache_key)
-    } else {
-        Ok(())
-    };
-    match cache_result {
+    let cache_entry = infcx.inner.borrow_mut().projection_cache().try_start(cache_key);
+    match cache_entry {
         Ok(()) => debug!("no cache"),
         Err(ProjectionCacheEntry::Ambiguous) => {
             // If we found ambiguity the last time, that means we will continue
@@ -378,10 +368,7 @@ pub(super) fn opt_normalize_projection_term<'a, 'b, 'tcx>(
             // Cache that normalizing this projection resulted in a cycle. This
             // should ensure that, unless this happens within a snapshot that's
             // rolled back, fulfillment or evaluation will notice the cycle.
-
-            if use_cache {
-                infcx.inner.borrow_mut().projection_cache().recur(cache_key);
-            }
+            infcx.inner.borrow_mut().projection_cache().recur(cache_key);
             return Err(InProgress);
         }
         Err(ProjectionCacheEntry::Recur) => {
@@ -445,26 +432,20 @@ pub(super) fn opt_normalize_projection_term<'a, 'b, 'tcx>(
             let mut deduped = SsoHashSet::with_capacity(result.obligations.len());
             result.obligations.retain(|obligation| deduped.insert(obligation.clone()));
 
-            if use_cache {
-                infcx.inner.borrow_mut().projection_cache().insert_term(cache_key, result.clone());
-            }
+            infcx.inner.borrow_mut().projection_cache().insert_term(cache_key, result.clone());
             obligations.extend(result.obligations);
             Ok(Some(result.value))
         }
         Ok(Projected::NoProgress(projected_ty)) => {
             let result =
                 Normalized { value: projected_ty, obligations: PredicateObligations::new() };
-            if use_cache {
-                infcx.inner.borrow_mut().projection_cache().insert_term(cache_key, result.clone());
-            }
+            infcx.inner.borrow_mut().projection_cache().insert_term(cache_key, result.clone());
             // No need to extend `obligations`.
             Ok(Some(result.value))
         }
         Err(ProjectionError::TooManyCandidates) => {
             debug!("opt_normalize_projection_type: too many candidates");
-            if use_cache {
-                infcx.inner.borrow_mut().projection_cache().ambiguous(cache_key);
-            }
+            infcx.inner.borrow_mut().projection_cache().ambiguous(cache_key);
             Ok(None)
         }
         Err(ProjectionError::TraitSelectionError(_)) => {
@@ -473,10 +454,7 @@ pub(super) fn opt_normalize_projection_term<'a, 'b, 'tcx>(
             // just return `ty::err` but add the obligation `T :
             // Trait`, which when processed will cause the error to be
             // reported later
-
-            if use_cache {
-                infcx.inner.borrow_mut().projection_cache().error(cache_key);
-            }
+            infcx.inner.borrow_mut().projection_cache().error(cache_key);
             let result = normalize_to_error(selcx, param_env, projection_term, cause, depth);
             obligations.extend(result.obligations);
             Ok(Some(result.value))
diff --git a/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs b/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs
index bb44645a4ce1c..9e1a2a3e7d286 100644
--- a/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs
@@ -87,7 +87,6 @@ impl<'tcx> InferCtxt<'tcx> {
                 Ok(result)
             })
         } else {
-            assert!(!self.intercrate);
             let c_pred =
                 self.canonicalize_query(param_env.and(obligation.predicate), &mut _orig_values);
             self.tcx.at(obligation.cause.span).evaluate_obligation(c_pred)
diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
index e027586563ecc..03fde1d159890 100644
--- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
@@ -16,7 +16,7 @@ use rustc_infer::traits::{
     Obligation, ObligationCause, PolyTraitObligation, PredicateObligations, SelectionError,
 };
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
-use rustc_middle::ty::{self, ToPolyTraitRef, Ty, TypeVisitableExt};
+use rustc_middle::ty::{self, ToPolyTraitRef, Ty, TypeVisitableExt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use tracing::{debug, instrument, trace};
 
@@ -790,7 +790,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                         //
                         // Note that this is only sound as projection candidates of opaque types
                         // are always applicable for auto traits.
-                    } else if self.infcx.intercrate {
+                    } else if let TypingMode::Coherence =
+                        self.infcx.typing_mode(obligation.param_env)
+                    {
                         // We do not emit auto trait candidates for opaque types in coherence.
                         // Doing so can result in weird dependency cycles.
                         candidates.ambiguous = true;
@@ -930,7 +932,10 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
     ) -> Option<ty::PolyExistentialTraitRef<'tcx>> {
         // Don't drop any candidates in intercrate mode, as it's incomplete.
         // (Not that it matters, since `Unsize` is not a stable trait.)
-        if self.infcx.intercrate {
+        //
+        // FIXME(@lcnr): This should probably only trigger during analysis,
+        // disabling candidates during codegen is also questionable.
+        if let TypingMode::Coherence = self.infcx.typing_mode(param_env) {
             return None;
         }
 
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index 635d3bc99b1ad..b1e5e5263151e 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -2,6 +2,7 @@
 //!
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/traits/resolution.html#selection
 
+use std::assert_matches::assert_matches;
 use std::cell::{Cell, RefCell};
 use std::fmt::{self, Display};
 use std::ops::ControlFlow;
@@ -28,7 +29,7 @@ use rustc_middle::ty::error::TypeErrorToStringExt;
 use rustc_middle::ty::print::{PrintTraitRefExt as _, with_no_trimmed_paths};
 use rustc_middle::ty::{
     self, GenericArgsRef, PolyProjectionPredicate, Ty, TyCtxt, TypeFoldable, TypeVisitableExt,
-    Upcast,
+    TypingMode, Upcast,
 };
 use rustc_span::Symbol;
 use rustc_span::symbol::sym;
@@ -222,7 +223,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
     /// Enables tracking of intercrate ambiguity causes. See
     /// the documentation of [`Self::intercrate_ambiguity_causes`] for more.
     pub fn enable_tracking_intercrate_ambiguity_causes(&mut self) {
-        assert!(self.is_intercrate());
+        assert_matches!(self.infcx.typing_mode_unchecked(), TypingMode::Coherence);
         assert!(self.intercrate_ambiguity_causes.is_none());
         self.intercrate_ambiguity_causes = Some(FxIndexSet::default());
         debug!("selcx: enable_tracking_intercrate_ambiguity_causes");
@@ -234,7 +235,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
     pub fn take_intercrate_ambiguity_causes(
         &mut self,
     ) -> FxIndexSet<IntercrateAmbiguityCause<'tcx>> {
-        assert!(self.is_intercrate());
+        assert_matches!(self.infcx.typing_mode_unchecked(), TypingMode::Coherence);
         self.intercrate_ambiguity_causes.take().unwrap_or_default()
     }
 
@@ -242,10 +243,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         self.infcx.tcx
     }
 
-    pub fn is_intercrate(&self) -> bool {
-        self.infcx.intercrate
-    }
-
     ///////////////////////////////////////////////////////////////////////////
     // Selection
     //
@@ -1029,7 +1026,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         previous_stack: TraitObligationStackList<'o, 'tcx>,
         mut obligation: PolyTraitObligation<'tcx>,
     ) -> Result<EvaluationResult, OverflowError> {
-        if !self.is_intercrate()
+        if !matches!(self.infcx.typing_mode(obligation.param_env), TypingMode::Coherence)
             && obligation.is_global()
             && obligation.param_env.caller_bounds().iter().all(|bound| bound.has_param())
         {
@@ -1312,14 +1309,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         param_env: ty::ParamEnv<'tcx>,
         trait_pred: ty::PolyTraitPredicate<'tcx>,
     ) -> Option<EvaluationResult> {
-        // Neither the global nor local cache is aware of intercrate
-        // mode, so don't do any caching. In particular, we might
-        // re-use the same `InferCtxt` with both an intercrate
-        // and non-intercrate `SelectionContext`
-        if self.is_intercrate() {
-            return None;
-        }
-
         let tcx = self.tcx();
         if self.can_use_global_caches(param_env) {
             if let Some(res) = tcx.evaluation_cache.get(&(param_env, trait_pred), tcx) {
@@ -1342,14 +1331,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             return;
         }
 
-        // Neither the global nor local cache is aware of intercrate
-        // mode, so don't do any caching. In particular, we might
-        // re-use the same `InferCtxt` with both an intercrate
-        // and non-intercrate `SelectionContext`
-        if self.is_intercrate() {
-            return;
-        }
-
         if self.can_use_global_caches(param_env) && !trait_pred.has_infer() {
             debug!(?trait_pred, ?result, "insert_evaluation_cache global");
             // This may overwrite the cache with the same value
@@ -1476,13 +1457,14 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
     }
 
     fn is_knowable<'o>(&mut self, stack: &TraitObligationStack<'o, 'tcx>) -> Result<(), Conflict> {
-        debug!("is_knowable(intercrate={:?})", self.is_intercrate());
-
-        if !self.is_intercrate() {
-            return Ok(());
+        let obligation = &stack.obligation;
+        match self.infcx.typing_mode(obligation.param_env) {
+            TypingMode::Coherence => {}
+            TypingMode::Analysis { .. } | TypingMode::PostAnalysis => return Ok(()),
         }
 
-        let obligation = &stack.obligation;
+        debug!("is_knowable()");
+
         let predicate = self.infcx.resolve_vars_if_possible(obligation.predicate);
 
         // Okay to skip binder because of the nature of the
@@ -1502,25 +1484,24 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             return false;
         }
 
-        // Avoid using the global cache during coherence and just rely
-        // on the local cache. This effectively disables caching
-        // during coherence. It is really just a simplification to
-        // avoid us having to fear that coherence results "pollute"
-        // the master cache. Since coherence executes pretty quickly,
-        // it's not worth going to more trouble to increase the
-        // hit-rate, I don't think.
-        if self.is_intercrate() {
-            return false;
-        }
-
-        // Avoid using the global cache when we're defining opaque types
-        // as their hidden type may impact the result of candidate selection.
-        if !self.infcx.defining_opaque_types().is_empty() {
-            return false;
+        match self.infcx.typing_mode(param_env) {
+            // Avoid using the global cache during coherence and just rely
+            // on the local cache. It is really just a simplification to
+            // avoid us having to fear that coherence results "pollute"
+            // the master cache. Since coherence executes pretty quickly,
+            // it's not worth going to more trouble to increase the
+            // hit-rate, I don't think.
+            TypingMode::Coherence => false,
+            // Avoid using the global cache when we're defining opaque types
+            // as their hidden type may impact the result of candidate selection.
+            TypingMode::Analysis { defining_opaque_types } => defining_opaque_types.is_empty(),
+            // The global cache is only used if there are no opaque types in
+            // the defining scope or we're outside of analysis.
+            //
+            // FIXME(#132279): This is still incorrect as we treat opaque types
+            // and default associated items differently between these two modes.
+            TypingMode::PostAnalysis => true,
         }
-
-        // Otherwise, we can use the global cache.
-        true
     }
 
     fn check_candidate_cache(
@@ -1528,13 +1509,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         param_env: ty::ParamEnv<'tcx>,
         cache_fresh_trait_pred: ty::PolyTraitPredicate<'tcx>,
     ) -> Option<SelectionResult<'tcx, SelectionCandidate<'tcx>>> {
-        // Neither the global nor local cache is aware of intercrate
-        // mode, so don't do any caching. In particular, we might
-        // re-use the same `InferCtxt` with both an intercrate
-        // and non-intercrate `SelectionContext`
-        if self.is_intercrate() {
-            return None;
-        }
         let tcx = self.tcx();
         let pred = cache_fresh_trait_pred.skip_binder();
 
@@ -1566,13 +1540,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         &self,
         result: &SelectionResult<'tcx, SelectionCandidate<'tcx>>,
     ) -> bool {
-        // Neither the global nor local cache is aware of intercrate
-        // mode, so don't do any caching. In particular, we might
-        // re-use the same `InferCtxt` with both an intercrate
-        // and non-intercrate `SelectionContext`
-        if self.is_intercrate() {
-            return false;
-        }
         match result {
             Ok(Some(SelectionCandidate::ParamCandidate(trait_ref))) => !trait_ref.has_infer(),
             _ => true,
@@ -2541,7 +2508,9 @@ impl<'tcx> SelectionContext<'_, 'tcx> {
             })?;
         nested_obligations.extend(obligations);
 
-        if !self.is_intercrate() && impl_trait_header.polarity == ty::ImplPolarity::Reservation {
+        if impl_trait_header.polarity == ty::ImplPolarity::Reservation
+            && !matches!(self.infcx.typing_mode(obligation.param_env), TypingMode::Coherence)
+        {
             debug!("reservation impls only apply in intercrate mode");
             return Err(());
         }
diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
index 0e45f7a195f04..5bf3dbcbc3273 100644
--- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
@@ -19,7 +19,9 @@ use rustc_infer::infer::DefineOpaqueTypes;
 use rustc_middle::bug;
 use rustc_middle::query::LocalCrate;
 use rustc_middle::ty::print::PrintTraitRefExt as _;
-use rustc_middle::ty::{self, GenericArgsRef, ImplSubject, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{
+    self, GenericArgsRef, ImplSubject, Ty, TyCtxt, TypeVisitableExt, TypingMode,
+};
 use rustc_session::lint::builtin::{COHERENCE_LEAK_CHECK, ORDER_DEPENDENT_TRAIT_OBJECTS};
 use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, sym};
 use specialization_graph::GraphExt;
@@ -184,7 +186,7 @@ pub(super) fn specializes(tcx: TyCtxt<'_>, (impl1_def_id, impl2_def_id): (DefId,
     let penv = tcx.param_env(impl1_def_id);
 
     // Create an infcx, taking the predicates of impl1 as assumptions:
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
 
     // Attempt to prove that impl2 applies, given all of the above.
     fulfill_implication(
diff --git a/compiler/rustc_trait_selection/src/traits/vtable.rs b/compiler/rustc_trait_selection/src/traits/vtable.rs
index ed221e2a1835f..bb56d6eaf544f 100644
--- a/compiler/rustc_trait_selection/src/traits/vtable.rs
+++ b/compiler/rustc_trait_selection/src/traits/vtable.rs
@@ -9,7 +9,8 @@ use rustc_infer::traits::util::PredicateSet;
 use rustc_middle::bug;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::{
-    self, GenericArgs, GenericParamDefKind, Ty, TyCtxt, TypeVisitableExt, Upcast, VtblEntry,
+    self, GenericArgs, GenericParamDefKind, Ty, TyCtxt, TypeVisitableExt, TypingMode, Upcast,
+    VtblEntry,
 };
 use rustc_span::{DUMMY_SP, Span, sym};
 use smallvec::{SmallVec, smallvec};
@@ -439,7 +440,7 @@ fn trait_refs_are_compatible<'tcx>(
         return false;
     }
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::PostAnalysis);
     let param_env = ty::ParamEnv::reveal_all();
     let ocx = ObligationCtxt::new(&infcx);
     let hr_source_principal =
diff --git a/compiler/rustc_traits/src/codegen.rs b/compiler/rustc_traits/src/codegen.rs
index 1118219824652..d8c1c50d79a85 100644
--- a/compiler/rustc_traits/src/codegen.rs
+++ b/compiler/rustc_traits/src/codegen.rs
@@ -6,7 +6,7 @@
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::bug;
 use rustc_middle::traits::CodegenObligationError;
-use rustc_middle::ty::{self, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, TyCtxt, TypeVisitableExt, TypingMode};
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::traits::{
     ImplSource, Obligation, ObligationCause, ObligationCtxt, ScrubbedTraitError, SelectionContext,
@@ -30,7 +30,7 @@ pub(crate) fn codegen_select_candidate<'tcx>(
 
     // Do the initial selection for the obligation. This yields the
     // shallow result we are looking for -- that is, what specific impl.
-    let infcx = tcx.infer_ctxt().ignoring_regions().build();
+    let infcx = tcx.infer_ctxt().ignoring_regions().build(TypingMode::from_param_env(param_env));
     let mut selcx = SelectionContext::new(&infcx);
 
     let obligation_cause = ObligationCause::dummy();
diff --git a/compiler/rustc_traits/src/normalize_erasing_regions.rs b/compiler/rustc_traits/src/normalize_erasing_regions.rs
index 3e2794f6489f8..d79059a39a1d1 100644
--- a/compiler/rustc_traits/src/normalize_erasing_regions.rs
+++ b/compiler/rustc_traits/src/normalize_erasing_regions.rs
@@ -1,7 +1,7 @@
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::query::Providers;
 use rustc_middle::traits::query::NoSolution;
-use rustc_middle::ty::{self, ParamEnvAnd, TyCtxt, TypeFoldable, TypeVisitableExt};
+use rustc_middle::ty::{self, ParamEnvAnd, TyCtxt, TypeFoldable, TypeVisitableExt, TypingMode};
 use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
 use rustc_trait_selection::traits::{Normalized, ObligationCause};
 use tracing::debug;
@@ -22,7 +22,7 @@ fn try_normalize_after_erasing_regions<'tcx, T: TypeFoldable<TyCtxt<'tcx>> + Par
     goal: ParamEnvAnd<'tcx, T>,
 ) -> Result<T, NoSolution> {
     let ParamEnvAnd { param_env, value } = goal;
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
     let cause = ObligationCause::dummy();
     match infcx.at(&cause, param_env).query_normalize(value) {
         Ok(Normalized { value: normalized_value, obligations: normalized_obligations }) => {
diff --git a/compiler/rustc_ty_utils/src/abi.rs b/compiler/rustc_ty_utils/src/abi.rs
index 48149a08de881..722ef5f456982 100644
--- a/compiler/rustc_ty_utils/src/abi.rs
+++ b/compiler/rustc_ty_utils/src/abi.rs
@@ -1,7 +1,7 @@
 use std::iter;
 
 use rustc_abi::Primitive::Pointer;
-use rustc_abi::{Abi, PointerKind, Scalar, Size};
+use rustc_abi::{BackendRepr, PointerKind, Scalar, Size};
 use rustc_hir as hir;
 use rustc_hir::lang_items::LangItem;
 use rustc_middle::bug;
@@ -469,7 +469,7 @@ fn fn_abi_sanity_check<'tcx>(
                 // careful. Scalar/ScalarPair is fine, since backends will generally use
                 // `layout.abi` and ignore everything else. We should just reject `Aggregate`
                 // entirely here, but some targets need to be fixed first.
-                if matches!(arg.layout.abi, Abi::Aggregate { .. }) {
+                if matches!(arg.layout.backend_repr, BackendRepr::Memory { .. }) {
                     // For an unsized type we'd only pass the sized prefix, so there is no universe
                     // in which we ever want to allow this.
                     assert!(
@@ -500,7 +500,7 @@ fn fn_abi_sanity_check<'tcx>(
                 // Similar to `Direct`, we need to make sure that backends use `layout.abi` and
                 // ignore the rest of the layout.
                 assert!(
-                    matches!(arg.layout.abi, Abi::ScalarPair(..)),
+                    matches!(arg.layout.backend_repr, BackendRepr::ScalarPair(..)),
                     "PassMode::Pair for type {}",
                     arg.layout.ty
                 );
@@ -658,9 +658,9 @@ fn fn_abi_adjust_for_abi<'tcx>(
         fn unadjust<'tcx>(arg: &mut ArgAbi<'tcx, Ty<'tcx>>) {
             // This still uses `PassMode::Pair` for ScalarPair types. That's unlikely to be intended,
             // but who knows what breaks if we change this now.
-            if matches!(arg.layout.abi, Abi::Aggregate { .. }) {
+            if matches!(arg.layout.backend_repr, BackendRepr::Memory { .. }) {
                 assert!(
-                    arg.layout.abi.is_sized(),
+                    arg.layout.backend_repr.is_sized(),
                     "'unadjusted' ABI does not support unsized arguments"
                 );
             }
@@ -731,8 +731,8 @@ fn make_thin_self_ptr<'tcx>(
         // FIXME (mikeyhew) change this to use &own if it is ever added to the language
         Ty::new_mut_ptr(tcx, layout.ty)
     } else {
-        match layout.abi {
-            Abi::ScalarPair(..) | Abi::Scalar(..) => (),
+        match layout.backend_repr {
+            BackendRepr::ScalarPair(..) | BackendRepr::Scalar(..) => (),
             _ => bug!("receiver type has unsupported layout: {:?}", layout),
         }
 
diff --git a/compiler/rustc_ty_utils/src/common_traits.rs b/compiler/rustc_ty_utils/src/common_traits.rs
index 51b908881eb49..c26b41d896005 100644
--- a/compiler/rustc_ty_utils/src/common_traits.rs
+++ b/compiler/rustc_ty_utils/src/common_traits.rs
@@ -3,7 +3,7 @@
 use rustc_hir::lang_items::LangItem;
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypingMode};
 use rustc_trait_selection::traits;
 
 fn is_copy_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
@@ -29,7 +29,7 @@ fn is_item_raw<'tcx>(
 ) -> bool {
     let (param_env, ty) = query.into_parts();
     let trait_def_id = tcx.require_lang_item(item, None);
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
     traits::type_known_to_meet_bound_modulo_regions(&infcx, param_env, ty, trait_def_id)
 }
 
diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs
index 9b764133f2c6a..e258b6dae0b46 100644
--- a/compiler/rustc_ty_utils/src/instance.rs
+++ b/compiler/rustc_ty_utils/src/instance.rs
@@ -6,7 +6,7 @@ use rustc_middle::bug;
 use rustc_middle::query::Providers;
 use rustc_middle::traits::{BuiltinImplSource, CodegenObligationError};
 use rustc_middle::ty::util::AsyncDropGlueMorphology;
-use rustc_middle::ty::{self, GenericArgsRef, Instance, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, GenericArgsRef, Instance, TyCtxt, TypeVisitableExt, TypingMode};
 use rustc_span::sym;
 use rustc_trait_selection::traits;
 use rustc_type_ir::ClosureKind;
@@ -130,7 +130,7 @@ fn resolve_associated_item<'tcx>(
                 .unwrap_or_else(|| {
                     bug!("{:?} not found in {:?}", trait_item_id, impl_data.impl_def_id);
                 });
-            let infcx = tcx.infer_ctxt().build();
+            let infcx = tcx.infer_ctxt().build(TypingMode::PostAnalysis);
             let param_env = param_env.with_reveal_all_normalized(tcx);
             let args = rcvr_args.rebase_onto(tcx, trait_def_id, impl_data.args);
             let args = translate_args(
diff --git a/compiler/rustc_ty_utils/src/layout.rs b/compiler/rustc_ty_utils/src/layout.rs
index 94b80e2694d8d..5ca7afe245396 100644
--- a/compiler/rustc_ty_utils/src/layout.rs
+++ b/compiler/rustc_ty_utils/src/layout.rs
@@ -5,8 +5,9 @@ use hir::def_id::DefId;
 use rustc_abi::Integer::{I8, I32};
 use rustc_abi::Primitive::{self, Float, Int, Pointer};
 use rustc_abi::{
-    Abi, AbiAndPrefAlign, AddressSpace, Align, FieldsShape, HasDataLayout, LayoutCalculatorError,
-    LayoutData, Niche, ReprOptions, Scalar, Size, StructKind, TagEncoding, Variants, WrappingRange,
+    AbiAndPrefAlign, AddressSpace, Align, BackendRepr, FieldsShape, HasDataLayout,
+    LayoutCalculatorError, LayoutData, Niche, ReprOptions, Scalar, Size, StructKind, TagEncoding,
+    Variants, WrappingRange,
 };
 use rustc_index::bit_set::BitSet;
 use rustc_index::{IndexSlice, IndexVec};
@@ -173,7 +174,9 @@ fn layout_of_uncached<'tcx>(
             let mut layout = LayoutData::clone(&layout.0);
             match *pat {
                 ty::PatternKind::Range { start, end, include_end } => {
-                    if let Abi::Scalar(scalar) | Abi::ScalarPair(scalar, _) = &mut layout.abi {
+                    if let BackendRepr::Scalar(scalar) | BackendRepr::ScalarPair(scalar, _) =
+                        &mut layout.backend_repr
+                    {
                         if let Some(start) = start {
                             scalar.valid_range_mut().start = start
                                 .try_to_bits(tcx, param_env)
@@ -275,7 +278,7 @@ fn layout_of_uncached<'tcx>(
                     return Ok(tcx.mk_layout(LayoutData::scalar(cx, data_ptr)));
                 }
 
-                let Abi::Scalar(metadata) = metadata_layout.abi else {
+                let BackendRepr::Scalar(metadata) = metadata_layout.backend_repr else {
                     return Err(error(cx, LayoutError::Unknown(pointee)));
                 };
 
@@ -330,9 +333,9 @@ fn layout_of_uncached<'tcx>(
                 .ok_or_else(|| error(cx, LayoutError::SizeOverflow(ty)))?;
 
             let abi = if count != 0 && ty.is_privately_uninhabited(tcx, param_env) {
-                Abi::Uninhabited
+                BackendRepr::Uninhabited
             } else {
-                Abi::Aggregate { sized: true }
+                BackendRepr::Memory { sized: true }
             };
 
             let largest_niche = if count != 0 { element.largest_niche } else { None };
@@ -340,7 +343,7 @@ fn layout_of_uncached<'tcx>(
             tcx.mk_layout(LayoutData {
                 variants: Variants::Single { index: FIRST_VARIANT },
                 fields: FieldsShape::Array { stride: element.size, count },
-                abi,
+                backend_repr: abi,
                 largest_niche,
                 align: element.align,
                 size,
@@ -353,7 +356,7 @@ fn layout_of_uncached<'tcx>(
             tcx.mk_layout(LayoutData {
                 variants: Variants::Single { index: FIRST_VARIANT },
                 fields: FieldsShape::Array { stride: element.size, count: 0 },
-                abi: Abi::Aggregate { sized: false },
+                backend_repr: BackendRepr::Memory { sized: false },
                 largest_niche: None,
                 align: element.align,
                 size: Size::ZERO,
@@ -364,7 +367,7 @@ fn layout_of_uncached<'tcx>(
         ty::Str => tcx.mk_layout(LayoutData {
             variants: Variants::Single { index: FIRST_VARIANT },
             fields: FieldsShape::Array { stride: Size::from_bytes(1), count: 0 },
-            abi: Abi::Aggregate { sized: false },
+            backend_repr: BackendRepr::Memory { sized: false },
             largest_niche: None,
             align: dl.i8_align,
             size: Size::ZERO,
@@ -384,8 +387,8 @@ fn layout_of_uncached<'tcx>(
                 &ReprOptions::default(),
                 StructKind::AlwaysSized,
             )?;
-            match unit.abi {
-                Abi::Aggregate { ref mut sized } => *sized = false,
+            match unit.backend_repr {
+                BackendRepr::Memory { ref mut sized } => *sized = false,
                 _ => bug!(),
             }
             tcx.mk_layout(unit)
@@ -500,7 +503,7 @@ fn layout_of_uncached<'tcx>(
 
             // Compute the ABI of the element type:
             let e_ly = cx.layout_of(e_ty)?;
-            let Abi::Scalar(e_abi) = e_ly.abi else {
+            let BackendRepr::Scalar(e_abi) = e_ly.backend_repr else {
                 // This error isn't caught in typeck, e.g., if
                 // the element type of the vector is generic.
                 tcx.dcx().emit_fatal(NonPrimitiveSimdType { ty, e_ty });
@@ -516,12 +519,12 @@ fn layout_of_uncached<'tcx>(
                 // Non-power-of-two vectors have padding up to the next power-of-two.
                 // If we're a packed repr, remove the padding while keeping the alignment as close
                 // to a vector as possible.
-                (Abi::Aggregate { sized: true }, AbiAndPrefAlign {
+                (BackendRepr::Memory { sized: true }, AbiAndPrefAlign {
                     abi: Align::max_for_offset(size),
                     pref: dl.vector_align(size).pref,
                 })
             } else {
-                (Abi::Vector { element: e_abi, count: e_len }, dl.vector_align(size))
+                (BackendRepr::Vector { element: e_abi, count: e_len }, dl.vector_align(size))
             };
             let size = size.align_to(align.abi);
 
@@ -535,7 +538,7 @@ fn layout_of_uncached<'tcx>(
             tcx.mk_layout(LayoutData {
                 variants: Variants::Single { index: FIRST_VARIANT },
                 fields,
-                abi,
+                backend_repr: abi,
                 largest_niche: e_ly.largest_niche,
                 size,
                 align,
@@ -985,10 +988,12 @@ fn coroutine_layout<'tcx>(
 
     size = size.align_to(align.abi);
 
-    let abi = if prefix.abi.is_uninhabited() || variants.iter().all(|v| v.abi.is_uninhabited()) {
-        Abi::Uninhabited
+    let abi = if prefix.backend_repr.is_uninhabited()
+        || variants.iter().all(|v| v.backend_repr.is_uninhabited())
+    {
+        BackendRepr::Uninhabited
     } else {
-        Abi::Aggregate { sized: true }
+        BackendRepr::Memory { sized: true }
     };
 
     let layout = tcx.mk_layout(LayoutData {
@@ -999,7 +1004,7 @@ fn coroutine_layout<'tcx>(
             variants,
         },
         fields: outer_fields,
-        abi,
+        backend_repr: abi,
         // Suppress niches inside coroutines. If the niche is inside a field that is aliased (due to
         // self-referentiality), getting the discriminant can cause aliasing violations.
         // `UnsafeCell` blocks niches for the same reason, but we don't yet have `UnsafePinned` that
diff --git a/compiler/rustc_ty_utils/src/layout/invariant.rs b/compiler/rustc_ty_utils/src/layout/invariant.rs
index 3db5a4f1805c6..f43feb552b289 100644
--- a/compiler/rustc_ty_utils/src/layout/invariant.rs
+++ b/compiler/rustc_ty_utils/src/layout/invariant.rs
@@ -66,12 +66,12 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
 
     fn check_layout_abi<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLayout<'tcx>) {
         // Verify the ABI mandated alignment and size.
-        let align = layout.abi.inherent_align(cx).map(|align| align.abi);
-        let size = layout.abi.inherent_size(cx);
+        let align = layout.backend_repr.inherent_align(cx).map(|align| align.abi);
+        let size = layout.backend_repr.inherent_size(cx);
         let Some((align, size)) = align.zip(size) else {
             assert_matches!(
-                layout.layout.abi(),
-                Abi::Uninhabited | Abi::Aggregate { .. },
+                layout.layout.backend_repr(),
+                BackendRepr::Uninhabited | BackendRepr::Memory { .. },
                 "ABI unexpectedly missing alignment and/or size in {layout:#?}"
             );
             return;
@@ -88,12 +88,12 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
         );
 
         // Verify per-ABI invariants
-        match layout.layout.abi() {
-            Abi::Scalar(_) => {
+        match layout.layout.backend_repr() {
+            BackendRepr::Scalar(_) => {
                 // Check that this matches the underlying field.
                 let inner = skip_newtypes(cx, layout);
                 assert!(
-                    matches!(inner.layout.abi(), Abi::Scalar(_)),
+                    matches!(inner.layout.backend_repr(), BackendRepr::Scalar(_)),
                     "`Scalar` type {} is newtype around non-`Scalar` type {}",
                     layout.ty,
                     inner.ty
@@ -132,7 +132,7 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
                             "`Scalar` field with bad align in {inner:#?}",
                         );
                         assert!(
-                            matches!(field.abi, Abi::Scalar(_)),
+                            matches!(field.backend_repr, BackendRepr::Scalar(_)),
                             "`Scalar` field with bad ABI in {inner:#?}",
                         );
                     }
@@ -141,11 +141,11 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
                     }
                 }
             }
-            Abi::ScalarPair(scalar1, scalar2) => {
+            BackendRepr::ScalarPair(scalar1, scalar2) => {
                 // Check that the underlying pair of fields matches.
                 let inner = skip_newtypes(cx, layout);
                 assert!(
-                    matches!(inner.layout.abi(), Abi::ScalarPair(..)),
+                    matches!(inner.layout.backend_repr(), BackendRepr::ScalarPair(..)),
                     "`ScalarPair` type {} is newtype around non-`ScalarPair` type {}",
                     layout.ty,
                     inner.ty
@@ -208,8 +208,8 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
                     "`ScalarPair` first field with bad align in {inner:#?}",
                 );
                 assert_matches!(
-                    field1.abi,
-                    Abi::Scalar(_),
+                    field1.backend_repr,
+                    BackendRepr::Scalar(_),
                     "`ScalarPair` first field with bad ABI in {inner:#?}",
                 );
                 let field2_offset = size1.align_to(align2);
@@ -226,16 +226,16 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
                     "`ScalarPair` second field with bad align in {inner:#?}",
                 );
                 assert_matches!(
-                    field2.abi,
-                    Abi::Scalar(_),
+                    field2.backend_repr,
+                    BackendRepr::Scalar(_),
                     "`ScalarPair` second field with bad ABI in {inner:#?}",
                 );
             }
-            Abi::Vector { element, .. } => {
+            BackendRepr::Vector { element, .. } => {
                 assert!(align >= element.align(cx).abi); // just sanity-checking `vector_align`.
                 // FIXME: Do some kind of check of the inner type, like for Scalar and ScalarPair.
             }
-            Abi::Uninhabited | Abi::Aggregate { .. } => {} // Nothing to check.
+            BackendRepr::Uninhabited | BackendRepr::Memory { .. } => {} // Nothing to check.
         }
     }
 
@@ -274,13 +274,13 @@ pub(super) fn partially_check_layout<'tcx>(cx: &LayoutCx<'tcx>, layout: &TyAndLa
             // The top-level ABI and the ABI of the variants should be coherent.
             let scalar_coherent =
                 |s1: Scalar, s2: Scalar| s1.size(cx) == s2.size(cx) && s1.align(cx) == s2.align(cx);
-            let abi_coherent = match (layout.abi, variant.abi) {
-                (Abi::Scalar(s1), Abi::Scalar(s2)) => scalar_coherent(s1, s2),
-                (Abi::ScalarPair(a1, b1), Abi::ScalarPair(a2, b2)) => {
+            let abi_coherent = match (layout.backend_repr, variant.backend_repr) {
+                (BackendRepr::Scalar(s1), BackendRepr::Scalar(s2)) => scalar_coherent(s1, s2),
+                (BackendRepr::ScalarPair(a1, b1), BackendRepr::ScalarPair(a2, b2)) => {
                     scalar_coherent(a1, a2) && scalar_coherent(b1, b2)
                 }
-                (Abi::Uninhabited, _) => true,
-                (Abi::Aggregate { .. }, _) => true,
+                (BackendRepr::Uninhabited, _) => true,
+                (BackendRepr::Memory { .. }, _) => true,
                 _ => false,
             };
             if !abi_coherent {
diff --git a/compiler/rustc_ty_utils/src/structural_match.rs b/compiler/rustc_ty_utils/src/structural_match.rs
index 1ead7b731e76c..0b4efab1d9c44 100644
--- a/compiler/rustc_ty_utils/src/structural_match.rs
+++ b/compiler/rustc_ty_utils/src/structural_match.rs
@@ -1,7 +1,7 @@
 use rustc_hir::lang_items::LangItem;
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypingMode};
 use rustc_trait_selection::traits::{ObligationCause, ObligationCtxt};
 
 /// This method returns true if and only if `adt_ty` itself has been marked as
@@ -11,7 +11,7 @@ use rustc_trait_selection::traits::{ObligationCause, ObligationCtxt};
 /// Note that this does *not* recursively check if the substructure of `adt_ty`
 /// implements the trait.
 fn has_structural_eq_impl<'tcx>(tcx: TyCtxt<'tcx>, adt_ty: Ty<'tcx>) -> bool {
-    let infcx = &tcx.infer_ctxt().build();
+    let infcx = &tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let cause = ObligationCause::dummy();
 
     let ocx = ObligationCtxt::new(infcx);
diff --git a/compiler/rustc_type_ir/src/canonical.rs b/compiler/rustc_type_ir/src/canonical.rs
index 3fb7d87bcc4bc..24b2ebc1fbe79 100644
--- a/compiler/rustc_type_ir/src/canonical.rs
+++ b/compiler/rustc_type_ir/src/canonical.rs
@@ -8,7 +8,7 @@ use rustc_macros::{HashStable_NoContext, TyDecodable, TyEncodable};
 use rustc_type_ir_macros::{Lift_Generic, TypeFoldable_Generic, TypeVisitable_Generic};
 
 use crate::inherent::*;
-use crate::{self as ty, Interner, UniverseIndex};
+use crate::{self as ty, Interner, TypingMode, UniverseIndex};
 
 #[derive_where(Clone; I: Interner, V: Clone)]
 #[derive_where(Hash; I: Interner, V: Hash)]
@@ -19,7 +19,7 @@ use crate::{self as ty, Interner, UniverseIndex};
 #[cfg_attr(feature = "nightly", derive(TyEncodable, TyDecodable, HashStable_NoContext))]
 pub struct CanonicalQueryInput<I: Interner, V> {
     pub canonical: Canonical<I, V>,
-    pub defining_opaque_types: I::DefiningOpaqueTypes,
+    pub typing_mode: TypingMode<I>,
 }
 
 /// A "canonicalized" type `V` is one where all free inference
diff --git a/compiler/rustc_type_ir/src/infer_ctxt.rs b/compiler/rustc_type_ir/src/infer_ctxt.rs
index 7c6a3c65ebfb4..22223e4a8900a 100644
--- a/compiler/rustc_type_ir/src/infer_ctxt.rs
+++ b/compiler/rustc_type_ir/src/infer_ctxt.rs
@@ -1,9 +1,68 @@
+use derive_where::derive_where;
+#[cfg(feature = "nightly")]
+use rustc_macros::{HashStable_NoContext, TyDecodable, TyEncodable};
+
 use crate::fold::TypeFoldable;
+use crate::inherent::*;
 use crate::relate::RelateResult;
 use crate::relate::combine::PredicateEmittingRelation;
-use crate::solve::SolverMode;
+use crate::solve::Reveal;
 use crate::{self as ty, Interner};
 
+/// The current typing mode of an inference context. We unfortunately have some
+/// slightly different typing rules depending on the current context. See the
+/// doc comment for each variant for how and why they are used.
+#[derive_where(Clone, Copy, Hash, PartialEq, Eq, Debug; I: Interner)]
+#[cfg_attr(feature = "nightly", derive(TyEncodable, TyDecodable, HashStable_NoContext))]
+pub enum TypingMode<I: Interner> {
+    /// When checking whether impls overlap, we check whether any obligations
+    /// are guaranteed to never hold when unifying the impls. This requires us
+    /// to be complete: we must never fail to prove something which may actually
+    /// hold.
+    ///
+    /// In this typing mode we bail with ambiguity in case its not knowable
+    /// whether a trait goal may hold, e.g. because the trait may get implemented
+    /// in a downstream or sibling crate.
+    ///
+    /// We also have to be careful when generalizing aliases inside of higher-ranked
+    /// types to not unnecessarily constrain any inference variables.
+    Coherence,
+    /// Analysis includes type inference, checking that items are well-formed, and
+    /// pretty much everything else which may emit proper type errors to the user.
+    ///
+    /// We only normalize opaque types which may get defined by the current body,
+    /// which are stored in `defining_opaque_types`.
+    Analysis { defining_opaque_types: I::DefiningOpaqueTypes },
+    /// After analysis, mostly during codegen and MIR optimizations, we're able to
+    /// reveal all opaque types.
+    PostAnalysis,
+}
+
+impl<I: Interner> TypingMode<I> {
+    /// Analysis outside of a body does not define any opaque types.
+    pub fn non_body_analysis() -> TypingMode<I> {
+        TypingMode::Analysis { defining_opaque_types: Default::default() }
+    }
+
+    /// While typechecking a body, we need to be able to define the opaque
+    /// types defined by that body.
+    pub fn analysis_in_body(cx: I, body_def_id: I::LocalDefId) -> TypingMode<I> {
+        TypingMode::Analysis { defining_opaque_types: cx.opaque_types_defined_by(body_def_id) }
+    }
+
+    /// FIXME(#132279): Using this function is questionable as the `param_env`
+    /// does not track `defining_opaque_types` and whether we're in coherence mode.
+    /// Many uses of this function should also use a not-yet implemented typing mode
+    /// which reveals already defined opaque types in the future. This function will
+    /// get completely removed at some point.
+    pub fn from_param_env(param_env: I::ParamEnv) -> TypingMode<I> {
+        match param_env.reveal() {
+            Reveal::UserFacing => TypingMode::non_body_analysis(),
+            Reveal::All => TypingMode::PostAnalysis,
+        }
+    }
+}
+
 pub trait InferCtxtLike: Sized {
     type Interner: Interner;
     fn cx(&self) -> Self::Interner;
@@ -16,7 +75,10 @@ pub trait InferCtxtLike: Sized {
         true
     }
 
-    fn solver_mode(&self) -> SolverMode;
+    fn typing_mode(
+        &self,
+        param_env_for_debug_assertion: <Self::Interner as Interner>::ParamEnv,
+    ) -> TypingMode<Self::Interner>;
 
     fn universe(&self) -> ty::UniverseIndex;
     fn create_next_universe(&self) -> ty::UniverseIndex;
@@ -43,8 +105,6 @@ pub trait InferCtxtLike: Sized {
         vid: ty::RegionVid,
     ) -> <Self::Interner as Interner>::Region;
 
-    fn defining_opaque_types(&self) -> <Self::Interner as Interner>::DefiningOpaqueTypes;
-
     fn next_ty_infer(&self) -> <Self::Interner as Interner>::Ty;
     fn next_const_infer(&self) -> <Self::Interner as Interner>::Const;
     fn fresh_args_for_item(
diff --git a/compiler/rustc_type_ir/src/interner.rs b/compiler/rustc_type_ir/src/interner.rs
index 6a8113b38b7bd..36ddddccfa253 100644
--- a/compiler/rustc_type_ir/src/interner.rs
+++ b/compiler/rustc_type_ir/src/interner.rs
@@ -11,9 +11,7 @@ use crate::inherent::*;
 use crate::ir_print::IrPrint;
 use crate::lang_items::TraitSolverLangItem;
 use crate::relate::Relate;
-use crate::solve::{
-    CanonicalInput, ExternalConstraintsData, PredefinedOpaquesData, QueryResult, SolverMode,
-};
+use crate::solve::{CanonicalInput, ExternalConstraintsData, PredefinedOpaquesData, QueryResult};
 use crate::visit::{Flags, TypeSuperVisitable, TypeVisitable};
 use crate::{self as ty, search_graph};
 
@@ -130,11 +128,7 @@ pub trait Interner:
     type Clause: Clause<Self>;
     type Clauses: Copy + Debug + Hash + Eq + TypeSuperVisitable<Self> + Flags;
 
-    fn with_global_cache<R>(
-        self,
-        mode: SolverMode,
-        f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R,
-    ) -> R;
+    fn with_global_cache<R>(self, f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R) -> R;
 
     fn evaluation_is_concurrent(&self) -> bool;
 
@@ -298,6 +292,11 @@ pub trait Interner:
         self,
         binder: ty::Binder<Self, T>,
     ) -> ty::Binder<Self, T>;
+
+    fn opaque_types_defined_by(
+        self,
+        defining_anchor: Self::LocalDefId,
+    ) -> Self::DefiningOpaqueTypes;
 }
 
 /// Imagine you have a function `F: FnOnce(&[T]) -> R`, plus an iterator `iter`
@@ -414,12 +413,8 @@ impl<I: Interner> search_graph::Cx for I {
     fn with_cached_task<T>(self, task: impl FnOnce() -> T) -> (T, I::DepNodeIndex) {
         I::with_cached_task(self, task)
     }
-    fn with_global_cache<R>(
-        self,
-        mode: SolverMode,
-        f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R,
-    ) -> R {
-        I::with_global_cache(self, mode, f)
+    fn with_global_cache<R>(self, f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R) -> R {
+        I::with_global_cache(self, f)
     }
     fn evaluation_is_concurrent(&self) -> bool {
         self.evaluation_is_concurrent()
diff --git a/compiler/rustc_type_ir/src/relate/combine.rs b/compiler/rustc_type_ir/src/relate/combine.rs
index 17a3912730f57..53751f7711a71 100644
--- a/compiler/rustc_type_ir/src/relate/combine.rs
+++ b/compiler/rustc_type_ir/src/relate/combine.rs
@@ -6,9 +6,9 @@ use super::{
 };
 use crate::error::TypeError;
 use crate::inherent::*;
-use crate::solve::{Goal, SolverMode};
+use crate::solve::Goal;
 use crate::visit::TypeVisitableExt as _;
-use crate::{self as ty, InferCtxtLike, Interner, Upcast};
+use crate::{self as ty, InferCtxtLike, Interner, TypingMode, Upcast};
 
 pub trait PredicateEmittingRelation<Infcx, I = <Infcx as InferCtxtLike>::Interner>:
     TypeRelation<I>
@@ -128,19 +128,19 @@ where
         }
 
         (ty::Alias(ty::Opaque, _), _) | (_, ty::Alias(ty::Opaque, _)) => {
-            match infcx.solver_mode() {
-                SolverMode::Normal => {
-                    assert!(!infcx.next_trait_solver());
-                    structurally_relate_tys(relation, a, b)
-                }
+            assert!(!infcx.next_trait_solver());
+            match infcx.typing_mode(relation.param_env()) {
                 // During coherence, opaque types should be treated as *possibly*
-                // equal to any other type (except for possibly itinfcx). This is an
+                // equal to any other type. This is an
                 // extremely heavy hammer, but can be relaxed in a forwards-compatible
                 // way later.
-                SolverMode::Coherence => {
+                TypingMode::Coherence => {
                     relation.register_predicates([ty::Binder::dummy(ty::PredicateKind::Ambiguous)]);
                     Ok(a)
                 }
+                TypingMode::Analysis { .. } | TypingMode::PostAnalysis => {
+                    structurally_relate_tys(relation, a, b)
+                }
             }
         }
 
diff --git a/compiler/rustc_type_ir/src/search_graph/mod.rs b/compiler/rustc_type_ir/src/search_graph/mod.rs
index 3fd2bb61ba583..5010fc09adc39 100644
--- a/compiler/rustc_type_ir/src/search_graph/mod.rs
+++ b/compiler/rustc_type_ir/src/search_graph/mod.rs
@@ -22,7 +22,6 @@ use rustc_index::{Idx, IndexVec};
 use tracing::debug;
 
 use crate::data_structures::HashMap;
-use crate::solve::SolverMode;
 
 mod global_cache;
 use global_cache::CacheData;
@@ -48,11 +47,7 @@ pub trait Cx: Copy {
     fn get_tracked<T: Debug + Clone>(self, tracked: &Self::Tracked<T>) -> T;
     fn with_cached_task<T>(self, task: impl FnOnce() -> T) -> (T, Self::DepNodeIndex);
 
-    fn with_global_cache<R>(
-        self,
-        mode: SolverMode,
-        f: impl FnOnce(&mut GlobalCache<Self>) -> R,
-    ) -> R;
+    fn with_global_cache<R>(self, f: impl FnOnce(&mut GlobalCache<Self>) -> R) -> R;
 
     fn evaluation_is_concurrent(&self) -> bool;
 }
@@ -358,7 +353,6 @@ struct ProvisionalCacheEntry<X: Cx> {
 }
 
 pub struct SearchGraph<D: Delegate<Cx = X>, X: Cx = <D as Delegate>::Cx> {
-    mode: SolverMode,
     root_depth: AvailableDepth,
     /// The stack of goals currently being computed.
     ///
@@ -374,9 +368,8 @@ pub struct SearchGraph<D: Delegate<Cx = X>, X: Cx = <D as Delegate>::Cx> {
 }
 
 impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
-    pub fn new(mode: SolverMode, root_depth: usize) -> SearchGraph<D> {
+    pub fn new(root_depth: usize) -> SearchGraph<D> {
         Self {
-            mode,
             root_depth: AvailableDepth(root_depth),
             stack: Default::default(),
             provisional_cache: Default::default(),
@@ -384,10 +377,6 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
         }
     }
 
-    pub fn solver_mode(&self) -> SolverMode {
-        self.mode
-    }
-
     /// Lazily update the stack entry for the parent goal.
     /// This behavior is shared between actually evaluating goals
     /// and using existing global cache entries to make sure they
@@ -829,7 +818,7 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
         input: X::Input,
         available_depth: AvailableDepth,
     ) -> Option<X::Result> {
-        cx.with_global_cache(self.mode, |cache| {
+        cx.with_global_cache(|cache| {
             cache
                 .get(cx, input, available_depth, |nested_goals| {
                     Self::candidate_is_applicable(
@@ -852,7 +841,7 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
         input: X::Input,
         available_depth: AvailableDepth,
     ) -> Option<X::Result> {
-        cx.with_global_cache(self.mode, |cache| {
+        cx.with_global_cache(|cache| {
             let CacheData { result, additional_depth, encountered_overflow, nested_goals } = cache
                 .get(cx, input, available_depth, |nested_goals| {
                     Self::candidate_is_applicable(
@@ -1041,7 +1030,7 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
     ) {
         let additional_depth = final_entry.reached_depth.as_usize() - self.stack.len();
         debug!(?final_entry, ?result, "insert global cache");
-        cx.with_global_cache(self.mode, |cache| {
+        cx.with_global_cache(|cache| {
             cache.insert(
                 cx,
                 input,
diff --git a/compiler/rustc_type_ir/src/solve/mod.rs b/compiler/rustc_type_ir/src/solve/mod.rs
index b3f8390bbf062..fe4558730513a 100644
--- a/compiler/rustc_type_ir/src/solve/mod.rs
+++ b/compiler/rustc_type_ir/src/solve/mod.rs
@@ -58,19 +58,6 @@ pub enum Reveal {
     All,
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub enum SolverMode {
-    /// Ordinary trait solving, using everywhere except for coherence.
-    Normal,
-    /// Trait solving during coherence. There are a few notable differences
-    /// between coherence and ordinary trait solving.
-    ///
-    /// Most importantly, trait solving during coherence must not be incomplete,
-    /// i.e. return `Err(NoSolution)` for goals for which a solution exists.
-    /// This means that we must not make any guesses or arbitrary choices.
-    Coherence,
-}
-
 pub type CanonicalInput<I, T = <I as Interner>::Predicate> =
     ty::CanonicalQueryInput<I, QueryInput<I, T>>;
 pub type CanonicalResponse<I> = Canonical<I, Response<I>>;
diff --git a/src/doc/rustc/src/platform-support/aix.md b/src/doc/rustc/src/platform-support/aix.md
index c3ce71a183568..5a198062b9529 100644
--- a/src/doc/rustc/src/platform-support/aix.md
+++ b/src/doc/rustc/src/platform-support/aix.md
@@ -6,8 +6,8 @@ Rust for AIX operating system, currently only 64-bit PowerPC is supported.
 
 ## Target maintainers
 
-- QIU Chaofan `qiucofan@cn.ibm.com`, https://github.com/ecnelises
-- Kai LUO, `lkail@cn.ibm.com`, https://github.com/bzEq
+- David Tenty `daltenty@ibm.com`, https://github.com/daltenty
+- Chris Cambly, `ccambly@ca.ibm.com`, https://github.com/gilamn5tr
 
 ## Requirements
 
diff --git a/src/doc/rustc/src/platform-support/fuchsia.md b/src/doc/rustc/src/platform-support/fuchsia.md
index 0622f4dd564de..489f46e1cb98d 100644
--- a/src/doc/rustc/src/platform-support/fuchsia.md
+++ b/src/doc/rustc/src/platform-support/fuchsia.md
@@ -7,17 +7,9 @@ updatable, and performant.
 
 ## Target maintainers
 
-The [Fuchsia team]:
+See [`fuchsia.toml`] in the `team` repository for current target maintainers.
 
-- Tyler Mandry ([@tmandry](https://github.com/tmandry))
-- David Koloski ([@djkoloski](https://github.com/djkoloski))
-- Julia Ryan ([@P1n3appl3](https://github.com/P1n3appl3))
-- Erick Tryzelaar ([@erickt](https://github.com/erickt))
-
-As the team evolves over time, the specific members listed here may differ from
-the members reported by the API. The API should be considered to be
-authoritative if this occurs. Instead of pinging individual members, use
-`@rustbot ping fuchsia` to contact the team on GitHub.
+[`fuchsia.toml`]: https://github.com/rust-lang/team/blob/master/teams/fuchsia.toml
 
 ## Table of contents
 
diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs
index 1f3cb4a61b895..a6d9676dd84ad 100644
--- a/src/librustdoc/clean/blanket_impl.rs
+++ b/src/librustdoc/clean/blanket_impl.rs
@@ -1,7 +1,7 @@
 use rustc_hir as hir;
 use rustc_infer::infer::{DefineOpaqueTypes, InferOk, TyCtxtInferExt};
 use rustc_infer::traits;
-use rustc_middle::ty::{self, Upcast};
+use rustc_middle::ty::{self, TypingMode, Upcast};
 use rustc_span::DUMMY_SP;
 use rustc_span::def_id::DefId;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
@@ -38,7 +38,7 @@ pub(crate) fn synthesize_blanket_impls(
             if !matches!(trait_ref.skip_binder().self_ty().kind(), ty::Param(_)) {
                 continue;
             }
-            let infcx = tcx.infer_ctxt().build();
+            let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
             let args = infcx.fresh_args_for_item(DUMMY_SP, item_def_id);
             let impl_ty = ty.instantiate(tcx, args);
             let param_env = ty::ParamEnv::empty();
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index ea349f878e0ef..87b629078ff8e 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -45,7 +45,7 @@ use rustc_hir::def_id::{DefId, DefIdMap, DefIdSet, LOCAL_CRATE, LocalDefId};
 use rustc_hir_analysis::lower_ty;
 use rustc_middle::metadata::Reexport;
 use rustc_middle::middle::resolve_bound_vars as rbv;
-use rustc_middle::ty::{self, AdtKind, GenericArgsRef, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, AdtKind, GenericArgsRef, Ty, TyCtxt, TypeVisitableExt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_span::ExpnKind;
 use rustc_span::hygiene::{AstPass, MacroKind};
@@ -1863,7 +1863,7 @@ fn normalize<'tcx>(
     use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
 
     // Try to normalize `<X as Y>::T` to a type
-    let infcx = cx.tcx.infer_ctxt().build();
+    let infcx = cx.tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let normalized = infcx
         .at(&ObligationCause::dummy(), cx.param_env)
         .query_normalize(ty)
@@ -2399,7 +2399,7 @@ pub(crate) fn clean_variant_def_with_args<'tcx>(
     use rustc_trait_selection::infer::TyCtxtInferExt;
     use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
 
-    let infcx = cx.tcx.infer_ctxt().build();
+    let infcx = cx.tcx.infer_ctxt().build(TypingMode::non_body_analysis());
     let kind = match variant.ctor_kind() {
         Some(CtorKind::Const) => VariantKind::CLike,
         Some(CtorKind::Fn) => VariantKind::Tuple(
diff --git a/src/librustdoc/html/format.rs b/src/librustdoc/html/format.rs
index 8e8e5c6ade8cb..47c21d89177bf 100644
--- a/src/librustdoc/html/format.rs
+++ b/src/librustdoc/html/format.rs
@@ -20,8 +20,7 @@ use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_metadata::creader::{CStore, LoadedMacro};
-use rustc_middle::ty;
-use rustc_middle::ty::TyCtxt;
+use rustc_middle::ty::{self, TyCtxt, TypingMode};
 use rustc_span::symbol::kw;
 use rustc_span::{Symbol, sym};
 use rustc_target::spec::abi::Abi;
@@ -613,7 +612,7 @@ fn generate_item_def_id_path(
     // No need to try to infer the actual parent item if it's not an associated item from the `impl`
     // block.
     if def_id != original_def_id && matches!(tcx.def_kind(def_id), DefKind::Impl { .. }) {
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::non_body_analysis());
         def_id = infcx
             .at(&ObligationCause::dummy(), tcx.param_env(def_id))
             .query_normalize(ty::Binder::dummy(tcx.type_of(def_id).instantiate_identity()))
diff --git a/src/tools/clippy/clippy_lints/src/eta_reduction.rs b/src/tools/clippy/clippy_lints/src/eta_reduction.rs
index cabc659225828..6ca599ed36113 100644
--- a/src/tools/clippy/clippy_lints/src/eta_reduction.rs
+++ b/src/tools/clippy/clippy_lints/src/eta_reduction.rs
@@ -9,7 +9,8 @@ use rustc_hir::{BindingMode, Expr, ExprKind, FnRetTy, Param, PatKind, QPath, Saf
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::{
-    self, Binder, ClosureKind, FnSig, GenericArg, GenericArgKind, List, Region, Ty, TypeVisitableExt, TypeckResults,
+    self, Binder, ClosureKind, FnSig, GenericArg, GenericArgKind, List, Region, Ty, TypeVisitableExt,
+    TypeckResults,
 };
 use rustc_session::declare_lint_pass;
 use rustc_span::symbol::sym;
@@ -203,7 +204,7 @@ fn check_clousure<'tcx>(cx: &LateContext<'tcx>, outer_receiver: Option<&Expr<'tc
                             // 'cuz currently nothing changes after deleting this check.
                             local_used_in(cx, l, args) || local_used_after_expr(cx, l, expr)
                         }) {
-                            match cx.tcx.infer_ctxt().build().err_ctxt().type_implements_fn_trait(
+                            match cx.tcx.infer_ctxt().build(cx.typing_mode()).err_ctxt().type_implements_fn_trait(
                                 cx.param_env,
                                 Binder::bind_with_vars(callee_ty_adjusted, List::empty()),
                                 ty::PredicatePolarity::Positive,
diff --git a/src/tools/clippy/clippy_lints/src/functions/must_use.rs b/src/tools/clippy/clippy_lints/src/functions/must_use.rs
index cfd11e9339fb7..c74ba088b78e6 100644
--- a/src/tools/clippy/clippy_lints/src/functions/must_use.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/must_use.rs
@@ -117,7 +117,7 @@ fn check_needless_must_use(
     } else if attr.value_str().is_none() && is_must_use_ty(cx, return_ty(cx, item_id)) {
         // Ignore async functions unless Future::Output type is a must_use type
         if sig.header.is_async() {
-            let infcx = cx.tcx.infer_ctxt().build();
+            let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
             if let Some(future_ty) = infcx.err_ctxt().get_impl_future_output_ty(return_ty(cx, item_id))
                 && !is_must_use_ty(cx, future_ty)
             {
diff --git a/src/tools/clippy/clippy_lints/src/future_not_send.rs b/src/tools/clippy/clippy_lints/src/future_not_send.rs
index a4dbe134f3650..cf08c16458bd5 100644
--- a/src/tools/clippy/clippy_lints/src/future_not_send.rs
+++ b/src/tools/clippy/clippy_lints/src/future_not_send.rs
@@ -74,7 +74,7 @@ impl<'tcx> LateLintPass<'tcx> for FutureNotSend {
             if is_future {
                 let send_trait = cx.tcx.get_diagnostic_item(sym::Send).unwrap();
                 let span = decl.output.span();
-                let infcx = cx.tcx.infer_ctxt().build();
+                let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
                 let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
                 let cause = traits::ObligationCause::misc(span, fn_def_id);
                 ocx.register_bound(cause, cx.param_env, ret_ty, send_trait);
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
index cfa1fdb81372f..82549413fa918 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
@@ -568,7 +568,7 @@ fn can_change_type<'a>(cx: &LateContext<'a>, mut expr: &'a Expr<'a>, mut ty: Ty<
                             let obligation = Obligation::new(cx.tcx, ObligationCause::dummy(), cx.param_env, predicate);
                             !cx.tcx
                                 .infer_ctxt()
-                                .build()
+                                .build(cx.typing_mode())
                                 .predicate_must_hold_modulo_regions(&obligation)
                         }) {
                             return false;
diff --git a/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs b/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs
index f6db12ed84e86..f7fa31d83aa4a 100644
--- a/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs
@@ -278,7 +278,7 @@ fn needless_borrow_count<'tcx>(
 
             let predicate = EarlyBinder::bind(predicate).instantiate(cx.tcx, &args_with_referent_ty[..]);
             let obligation = Obligation::new(cx.tcx, ObligationCause::dummy(), cx.param_env, predicate);
-            let infcx = cx.tcx.infer_ctxt().build();
+            let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
             infcx.predicate_must_hold_modulo_regions(&obligation)
         })
     };
diff --git a/src/tools/clippy/clippy_lints/src/no_effect.rs b/src/tools/clippy/clippy_lints/src/no_effect.rs
index 392cfcb813e85..2e5195d459f4d 100644
--- a/src/tools/clippy/clippy_lints/src/no_effect.rs
+++ b/src/tools/clippy/clippy_lints/src/no_effect.rs
@@ -160,7 +160,7 @@ impl NoEffect {
                                 // Remove `impl Future<Output = T>` to get `T`
                                 if cx.tcx.ty_is_opaque_future(ret_ty)
                                     && let Some(true_ret_ty) =
-                                        cx.tcx.infer_ctxt().build().err_ctxt().get_impl_future_output_ty(ret_ty)
+                                        cx.tcx.infer_ctxt().build(cx.typing_mode()).err_ctxt().get_impl_future_output_ty(ret_ty)
                                 {
                                     ret_ty = true_ret_ty;
                                 }
diff --git a/src/tools/clippy/clippy_lints/src/ptr.rs b/src/tools/clippy/clippy_lints/src/ptr.rs
index f5fcf521b96cc..a548c6ef3b1fd 100644
--- a/src/tools/clippy/clippy_lints/src/ptr.rs
+++ b/src/tools/clippy/clippy_lints/src/ptr.rs
@@ -695,7 +695,7 @@ fn matches_preds<'tcx>(
     ty: Ty<'tcx>,
     preds: &'tcx [ty::PolyExistentialPredicate<'tcx>],
 ) -> bool {
-    let infcx = cx.tcx.infer_ctxt().build();
+    let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
     preds
         .iter()
         .all(|&p| match cx.tcx.instantiate_bound_regions_with_erased(p) {
diff --git a/src/tools/clippy/clippy_lints/src/useless_conversion.rs b/src/tools/clippy/clippy_lints/src/useless_conversion.rs
index ec3a693d2efec..3b05abc546f47 100644
--- a/src/tools/clippy/clippy_lints/src/useless_conversion.rs
+++ b/src/tools/clippy/clippy_lints/src/useless_conversion.rs
@@ -114,7 +114,7 @@ fn into_iter_bound<'tcx>(
                     if !cx
                         .tcx
                         .infer_ctxt()
-                        .build()
+                        .build(cx.typing_mode())
                         .predicate_must_hold_modulo_regions(&obligation)
                     {
                         return None;
diff --git a/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs b/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs
index a00196c4b511d..6b3078f52aff5 100644
--- a/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs
+++ b/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs
@@ -185,9 +185,7 @@ impl<'b, 'tcx> PossibleBorrowerMap<'b, 'tcx> {
             vis.into_map(cx)
         };
         let maybe_storage_live_result = MaybeStorageLive::new(Cow::Owned(BitSet::new_empty(mir.local_decls.len())))
-            .into_engine(cx.tcx, mir)
-            .pass_name("redundant_clone")
-            .iterate_to_fixpoint()
+            .iterate_to_fixpoint(cx.tcx, mir, Some("redundant_clone"))
             .into_results_cursor(mir);
         let mut vis = PossibleBorrowerVisitor::new(cx, mir, possible_origin);
         vis.visit_body(mir);
diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
index 46739862de6b2..dbadc8432f630 100644
--- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
+++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
@@ -17,7 +17,7 @@ use rustc_middle::mir::{
 };
 use rustc_middle::traits::{BuiltinImplSource, ImplSource, ObligationCause};
 use rustc_middle::ty::adjustment::PointerCoercion;
-use rustc_middle::ty::{self, GenericArgKind, TraitRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArgKind, TraitRef, Ty, TyCtxt, TypingMode};
 use rustc_span::Span;
 use rustc_span::symbol::sym;
 use rustc_trait_selection::traits::{ObligationCtxt, SelectionContext};
@@ -420,7 +420,7 @@ fn is_ty_const_destruct<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, body: &Body<'tcx>
             TraitRef::new(tcx, tcx.require_lang_item(LangItem::Destruct, Some(body.span)), [ty]),
         );
 
-        let infcx = tcx.infer_ctxt().build();
+        let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(obligation.param_env));
         let mut selcx = SelectionContext::new(&infcx);
         let Some(impl_src) = selcx.select(&obligation).ok().flatten() else {
             return false;
diff --git a/src/tools/clippy/clippy_utils/src/ty.rs b/src/tools/clippy/clippy_utils/src/ty.rs
index 07c3d0eada005..c618bfe4488c1 100644
--- a/src/tools/clippy/clippy_utils/src/ty.rs
+++ b/src/tools/clippy/clippy_utils/src/ty.rs
@@ -19,7 +19,7 @@ use rustc_middle::ty::layout::ValidityRequirement;
 use rustc_middle::ty::{
     self, AdtDef, AliasTy, AssocItem, AssocKind, Binder, BoundRegion, FnSig, GenericArg, GenericArgKind,
     GenericArgsRef, GenericParamDefKind, IntTy, ParamEnv, Region, RegionKind, TraitRef, Ty, TyCtxt, TypeSuperVisitable,
-    TypeVisitable, TypeVisitableExt, TypeVisitor, UintTy, Upcast, VariantDef, VariantDiscr,
+    TypeVisitable, TypeVisitableExt, TypeVisitor, UintTy, Upcast, VariantDef, VariantDiscr, TypingMode,
 };
 use rustc_span::symbol::Ident;
 use rustc_span::{DUMMY_SP, Span, Symbol, sym};
@@ -268,7 +268,7 @@ pub fn implements_trait_with_env_from_iter<'tcx>(
         return false;
     }
 
-    let infcx = tcx.infer_ctxt().build();
+    let infcx = tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
     let args = args
         .into_iter()
         .map(|arg| arg.into().unwrap_or_else(|| infcx.next_ty_var(DUMMY_SP).into()))
@@ -362,7 +362,7 @@ fn is_normalizable_helper<'tcx>(
     }
     // prevent recursive loops, false-negative is better than endless loop leading to stack overflow
     cache.insert(ty, false);
-    let infcx = cx.tcx.infer_ctxt().build();
+    let infcx = cx.tcx.infer_ctxt().build(TypingMode::from_param_env(param_env));
     let cause = ObligationCause::dummy();
     let result = if infcx.at(&cause, param_env).query_normalize(ty).is_ok() {
         match ty.kind() {
@@ -1268,7 +1268,7 @@ pub fn make_normalized_projection_with_regions<'tcx>(
         let cause = ObligationCause::dummy();
         match tcx
             .infer_ctxt()
-            .build()
+            .build(TypingMode::from_param_env(param_env))
             .at(&cause, param_env)
             .query_normalize(Ty::new_projection_from_args(tcx, ty.def_id, ty.args))
         {
@@ -1284,7 +1284,7 @@ pub fn make_normalized_projection_with_regions<'tcx>(
 
 pub fn normalize_with_regions<'tcx>(tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
     let cause = ObligationCause::dummy();
-    match tcx.infer_ctxt().build().at(&cause, param_env).query_normalize(ty) {
+    match tcx.infer_ctxt().build(TypingMode::from_param_env(param_env)).at(&cause, param_env).query_normalize(ty) {
         Ok(ty) => ty.value,
         Err(_) => ty,
     }
diff --git a/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs b/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs
index fdc7a675fb713..47fe41d9ecdd8 100644
--- a/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs
+++ b/src/tools/miri/src/borrow_tracker/stacked_borrows/mod.rs
@@ -9,11 +9,11 @@ use std::cell::RefCell;
 use std::fmt::Write;
 use std::{cmp, mem};
 
+use rustc_abi::{BackendRepr, Size};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::mir::{Mutability, RetagKind};
 use rustc_middle::ty::layout::HasParamEnv;
 use rustc_middle::ty::{self, Ty};
-use rustc_target::abi::{Abi, Size};
 
 use self::diagnostics::{RetagCause, RetagInfo};
 pub use self::item::{Item, Permission};
@@ -972,7 +972,10 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                             RetagFields::OnlyScalar => {
                                 // Matching `ArgAbi::new` at the time of writing, only fields of
                                 // `Scalar` and `ScalarPair` ABI are considered.
-                                matches!(place.layout.abi, Abi::Scalar(..) | Abi::ScalarPair(..))
+                                matches!(
+                                    place.layout.backend_repr,
+                                    BackendRepr::Scalar(..) | BackendRepr::ScalarPair(..)
+                                )
                             }
                         };
                         if recurse {
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
index acfb76030f5ff..40467aa4bc1be 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
@@ -1,8 +1,8 @@
+use rustc_abi::{BackendRepr, Size};
 use rustc_middle::mir::{Mutability, RetagKind};
 use rustc_middle::ty::layout::HasParamEnv;
 use rustc_middle::ty::{self, Ty};
 use rustc_span::def_id::DefId;
-use rustc_target::abi::{Abi, Size};
 
 use crate::borrow_tracker::{GlobalState, GlobalStateInner, ProtectorKind};
 use crate::concurrency::data_race::NaReadType;
@@ -495,7 +495,10 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                             RetagFields::OnlyScalar => {
                                 // Matching `ArgAbi::new` at the time of writing, only fields of
                                 // `Scalar` and `ScalarPair` ABI are considered.
-                                matches!(place.layout.abi, Abi::Scalar(..) | Abi::ScalarPair(..))
+                                matches!(
+                                    place.layout.backend_repr,
+                                    BackendRepr::Scalar(..) | BackendRepr::ScalarPair(..)
+                                )
                             }
                         };
                         if recurse {
diff --git a/src/tools/miri/src/helpers.rs b/src/tools/miri/src/helpers.rs
index d35cbf242f5d1..17f664da85382 100644
--- a/src/tools/miri/src/helpers.rs
+++ b/src/tools/miri/src/helpers.rs
@@ -349,8 +349,12 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         i: impl Into<i128>,
         dest: &impl Writeable<'tcx, Provenance>,
     ) -> InterpResult<'tcx> {
-        assert!(dest.layout().abi.is_scalar(), "write_int on non-scalar type {}", dest.layout().ty);
-        let val = if dest.layout().abi.is_signed() {
+        assert!(
+            dest.layout().backend_repr.is_scalar(),
+            "write_int on non-scalar type {}",
+            dest.layout().ty
+        );
+        let val = if dest.layout().backend_repr.is_signed() {
             Scalar::from_int(i, dest.layout().size)
         } else {
             // `unwrap` can only fail here if `i` is negative
diff --git a/src/tools/miri/src/lib.rs b/src/tools/miri/src/lib.rs
index 938d1ca319e0f..f903ccbc25a74 100644
--- a/src/tools/miri/src/lib.rs
+++ b/src/tools/miri/src/lib.rs
@@ -55,6 +55,7 @@ extern crate either;
 extern crate tracing;
 
 // The rustc crates we need
+extern crate rustc_abi;
 extern crate rustc_apfloat;
 extern crate rustc_ast;
 extern crate rustc_attr;
diff --git a/src/tools/miri/src/operator.rs b/src/tools/miri/src/operator.rs
index 8e06f4258d614..608e23fc1108a 100644
--- a/src/tools/miri/src/operator.rs
+++ b/src/tools/miri/src/operator.rs
@@ -23,7 +23,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         interp_ok(match bin_op {
             Eq | Ne | Lt | Le | Gt | Ge => {
-                assert_eq!(left.layout.abi, right.layout.abi); // types can differ, e.g. fn ptrs with different `for`
+                assert_eq!(left.layout.backend_repr, right.layout.backend_repr); // types can differ, e.g. fn ptrs with different `for`
                 let size = this.pointer_size();
                 // Just compare the bits. ScalarPairs are compared lexicographically.
                 // We thus always compare pairs and simply fill scalars up with 0.
diff --git a/src/tools/miri/src/shims/native_lib.rs b/src/tools/miri/src/shims/native_lib.rs
index 3f282017bb79d..525bcd381d52c 100644
--- a/src/tools/miri/src/shims/native_lib.rs
+++ b/src/tools/miri/src/shims/native_lib.rs
@@ -5,7 +5,7 @@ use libffi::high::call as ffi;
 use libffi::low::CodePtr;
 use rustc_middle::ty::{self as ty, IntTy, UintTy};
 use rustc_span::Symbol;
-use rustc_target::abi::{Abi, HasDataLayout};
+use rustc_abi::{BackendRepr, HasDataLayout};
 
 use crate::*;
 
@@ -149,7 +149,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         // Get the function arguments, and convert them to `libffi`-compatible form.
         let mut libffi_args = Vec::<CArg>::with_capacity(args.len());
         for arg in args.iter() {
-            if !matches!(arg.layout.abi, Abi::Scalar(_)) {
+            if !matches!(arg.layout.backend_repr, BackendRepr::Scalar(_)) {
                 throw_unsup_format!("only scalar argument types are support for native calls")
             }
             libffi_args.push(imm_to_carg(this.read_immediate(arg)?, this)?);
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/layout.rs b/src/tools/rust-analyzer/crates/hir-ty/src/layout.rs
index 9f4cc98993e24..c5fa20bc8acbc 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/layout.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/layout.rs
@@ -6,7 +6,7 @@ use base_db::ra_salsa::Cycle;
 use chalk_ir::{AdtId, FloatTy, IntTy, TyKind, UintTy};
 use hir_def::{
     layout::{
-        Abi, FieldsShape, Float, Integer, LayoutCalculator, LayoutCalculatorError, LayoutData,
+        BackendRepr, FieldsShape, Float, Integer, LayoutCalculator, LayoutCalculatorError, LayoutData,
         Primitive, ReprOptions, Scalar, Size, StructKind, TargetDataLayout, WrappingRange,
     },
     LocalFieldId, StructId,
@@ -168,7 +168,7 @@ fn layout_of_simd_ty(
 
     // Compute the ABI of the element type:
     let e_ly = db.layout_of_ty(e_ty, env)?;
-    let Abi::Scalar(e_abi) = e_ly.abi else {
+    let BackendRepr::Scalar(e_abi) = e_ly.backend_repr else {
         return Err(LayoutError::Unknown);
     };
 
@@ -190,7 +190,7 @@ fn layout_of_simd_ty(
     Ok(Arc::new(Layout {
         variants: Variants::Single { index: struct_variant_idx() },
         fields,
-        abi: Abi::Vector { element: e_abi, count: e_len },
+        backend_repr: BackendRepr::Vector { element: e_abi, count: e_len },
         largest_niche: e_ly.largest_niche,
         size,
         align,
@@ -294,10 +294,10 @@ pub fn layout_of_ty_query(
                 .checked_mul(count, dl)
                 .ok_or(LayoutError::BadCalc(LayoutCalculatorError::SizeOverflow))?;
 
-            let abi = if count != 0 && matches!(element.abi, Abi::Uninhabited) {
-                Abi::Uninhabited
+            let backend_repr = if count != 0 && matches!(element.backend_repr, BackendRepr::Uninhabited) {
+                BackendRepr::Uninhabited
             } else {
-                Abi::Aggregate { sized: true }
+                BackendRepr::Memory { sized: true }
             };
 
             let largest_niche = if count != 0 { element.largest_niche } else { None };
@@ -305,7 +305,7 @@ pub fn layout_of_ty_query(
             Layout {
                 variants: Variants::Single { index: struct_variant_idx() },
                 fields: FieldsShape::Array { stride: element.size, count },
-                abi,
+                backend_repr,
                 largest_niche,
                 align: element.align,
                 size,
@@ -318,7 +318,7 @@ pub fn layout_of_ty_query(
             Layout {
                 variants: Variants::Single { index: struct_variant_idx() },
                 fields: FieldsShape::Array { stride: element.size, count: 0 },
-                abi: Abi::Aggregate { sized: false },
+                backend_repr: BackendRepr::Memory { sized: false },
                 largest_niche: None,
                 align: element.align,
                 size: Size::ZERO,
@@ -329,7 +329,7 @@ pub fn layout_of_ty_query(
         TyKind::Str => Layout {
             variants: Variants::Single { index: struct_variant_idx() },
             fields: FieldsShape::Array { stride: Size::from_bytes(1), count: 0 },
-            abi: Abi::Aggregate { sized: false },
+            backend_repr: BackendRepr::Memory { sized: false },
             largest_niche: None,
             align: dl.i8_align,
             size: Size::ZERO,
@@ -379,8 +379,8 @@ pub fn layout_of_ty_query(
         TyKind::Never => cx.calc.layout_of_never_type(),
         TyKind::Dyn(_) | TyKind::Foreign(_) => {
             let mut unit = layout_of_unit(&cx)?;
-            match &mut unit.abi {
-                Abi::Aggregate { sized } => *sized = false,
+            match &mut unit.backend_repr {
+                BackendRepr::Memory { sized } => *sized = false,
                 _ => return Err(LayoutError::Unknown),
             }
             unit
diff --git a/tests/ui/abi/c-zst.other-linux.stderr b/tests/ui/abi/c-zst.other-linux.stderr
index 5a656e6ea66e0..2965979b26ddf 100644
--- a/tests/ui/abi/c-zst.other-linux.stderr
+++ b/tests/ui/abi/c-zst.other-linux.stderr
@@ -9,7 +9,7 @@ error: fn_abi_of(pass_zst) = FnAbi {
                                abi: $SOME_ALIGN,
                                pref: $SOME_ALIGN,
                            },
-                           abi: Aggregate {
+                           abi: Memory {
                                sized: true,
                            },
                            fields: Arbitrary {
@@ -36,7 +36,7 @@ error: fn_abi_of(pass_zst) = FnAbi {
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/abi/debug.stderr b/tests/ui/abi/debug.stderr
index 7365839da89dc..aa51c42c58dc4 100644
--- a/tests/ui/abi/debug.stderr
+++ b/tests/ui/abi/debug.stderr
@@ -235,7 +235,7 @@ error: fn_abi_of(test_generic) = FnAbi {
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -317,7 +317,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -387,7 +387,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -426,7 +426,7 @@ error: ABIs are not compatible
                                abi: $SOME_ALIGN,
                                pref: $SOME_ALIGN,
                            },
-                           abi: Aggregate {
+                           abi: Memory {
                                sized: true,
                            },
                            fields: Array {
@@ -464,7 +464,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -497,7 +497,7 @@ error: ABIs are not compatible
                                abi: $SOME_ALIGN,
                                pref: $SOME_ALIGN,
                            },
-                           abi: Aggregate {
+                           abi: Memory {
                                sized: true,
                            },
                            fields: Array {
@@ -535,7 +535,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -610,7 +610,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -680,7 +680,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -756,7 +756,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -826,7 +826,7 @@ error: ABIs are not compatible
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -929,7 +929,7 @@ error: fn_abi_of(assoc_test) = FnAbi {
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/abi/sysv64-zst.stderr b/tests/ui/abi/sysv64-zst.stderr
index 8b0b84dfa0699..8e1791e27d27c 100644
--- a/tests/ui/abi/sysv64-zst.stderr
+++ b/tests/ui/abi/sysv64-zst.stderr
@@ -9,7 +9,7 @@ error: fn_abi_of(pass_zst) = FnAbi {
                                abi: $SOME_ALIGN,
                                pref: $SOME_ALIGN,
                            },
-                           abi: Aggregate {
+                           abi: Memory {
                                sized: true,
                            },
                            fields: Arbitrary {
@@ -36,7 +36,7 @@ error: fn_abi_of(pass_zst) = FnAbi {
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/abi/win64-zst.other.stderr b/tests/ui/abi/win64-zst.other.stderr
index 15db141cb5748..5f99feeccb03b 100644
--- a/tests/ui/abi/win64-zst.other.stderr
+++ b/tests/ui/abi/win64-zst.other.stderr
@@ -9,7 +9,7 @@ error: fn_abi_of(pass_zst) = FnAbi {
                                abi: $SOME_ALIGN,
                                pref: $SOME_ALIGN,
                            },
-                           abi: Aggregate {
+                           abi: Memory {
                                sized: true,
                            },
                            fields: Arbitrary {
@@ -36,7 +36,7 @@ error: fn_abi_of(pass_zst) = FnAbi {
                            abi: $SOME_ALIGN,
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/array-slice-vec/vec-macro-with-comma-only.rs b/tests/ui/array-slice-vec/vec-macro-with-comma-only.rs
index 574a53c58feac..0f99f6b1b1e07 100644
--- a/tests/ui/array-slice-vec/vec-macro-with-comma-only.rs
+++ b/tests/ui/array-slice-vec/vec-macro-with-comma-only.rs
@@ -1,3 +1,3 @@
 pub fn main() {
-    vec![,]; //~ ERROR no rules expected the token `,`
+    vec![,]; //~ ERROR no rules expected `,`
 }
diff --git a/tests/ui/array-slice-vec/vec-macro-with-comma-only.stderr b/tests/ui/array-slice-vec/vec-macro-with-comma-only.stderr
index b3f953af6d278..d76d493eca839 100644
--- a/tests/ui/array-slice-vec/vec-macro-with-comma-only.stderr
+++ b/tests/ui/array-slice-vec/vec-macro-with-comma-only.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `,`
+error: no rules expected `,`
   --> $DIR/vec-macro-with-comma-only.rs:2:10
    |
 LL |     vec![,];
diff --git a/tests/ui/editions/edition-keywords-2015-2015-parsing.rs b/tests/ui/editions/edition-keywords-2015-2015-parsing.rs
index 07104bdf217d0..4751d280467cb 100644
--- a/tests/ui/editions/edition-keywords-2015-2015-parsing.rs
+++ b/tests/ui/editions/edition-keywords-2015-2015-parsing.rs
@@ -13,8 +13,8 @@ pub fn check_async() {
     let mut r#async = 1; // OK
 
     r#async = consumes_async!(async); // OK
-    r#async = consumes_async!(r#async); //~ ERROR no rules expected the token `r#async`
-    r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
+    r#async = consumes_async!(r#async); //~ ERROR no rules expected `r#async`
+    r#async = consumes_async_raw!(async); //~ ERROR no rules expected `async`
     r#async = consumes_async_raw!(r#async); // OK
 
     if passes_ident!(async) == 1 {} // OK
diff --git a/tests/ui/editions/edition-keywords-2015-2015-parsing.stderr b/tests/ui/editions/edition-keywords-2015-2015-parsing.stderr
index 39944622d07b9..2519a9fded2ee 100644
--- a/tests/ui/editions/edition-keywords-2015-2015-parsing.stderr
+++ b/tests/ui/editions/edition-keywords-2015-2015-parsing.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `r#async`
+error: no rules expected `r#async`
   --> $DIR/edition-keywords-2015-2015-parsing.rs:16:31
    |
 LL |     r#async = consumes_async!(r#async);
@@ -10,7 +10,7 @@ note: while trying to match `async`
 LL |     (async) => (1)
    |      ^^^^^
 
-error: no rules expected the token `async`
+error: no rules expected `async`
   --> $DIR/edition-keywords-2015-2015-parsing.rs:17:35
    |
 LL |     r#async = consumes_async_raw!(async);
diff --git a/tests/ui/editions/edition-keywords-2015-2018-parsing.rs b/tests/ui/editions/edition-keywords-2015-2018-parsing.rs
index 3c294f95cd265..4404ea26fb30d 100644
--- a/tests/ui/editions/edition-keywords-2015-2018-parsing.rs
+++ b/tests/ui/editions/edition-keywords-2015-2018-parsing.rs
@@ -13,8 +13,8 @@ pub fn check_async() {
     let mut r#async = 1; // OK
 
     r#async = consumes_async!(async); // OK
-    r#async = consumes_async!(r#async); //~ ERROR no rules expected the token `r#async`
-    r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
+    r#async = consumes_async!(r#async); //~ ERROR no rules expected `r#async`
+    r#async = consumes_async_raw!(async); //~ ERROR no rules expected `async`
     r#async = consumes_async_raw!(r#async); // OK
 
     if passes_ident!(async) == 1 {} // OK
diff --git a/tests/ui/editions/edition-keywords-2015-2018-parsing.stderr b/tests/ui/editions/edition-keywords-2015-2018-parsing.stderr
index fa83908e6666e..0c0e573841519 100644
--- a/tests/ui/editions/edition-keywords-2015-2018-parsing.stderr
+++ b/tests/ui/editions/edition-keywords-2015-2018-parsing.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `r#async`
+error: no rules expected `r#async`
   --> $DIR/edition-keywords-2015-2018-parsing.rs:16:31
    |
 LL |     r#async = consumes_async!(r#async);
@@ -10,7 +10,7 @@ note: while trying to match `async`
 LL |     (async) => (1)
    |      ^^^^^
 
-error: no rules expected the token `async`
+error: no rules expected `async`
   --> $DIR/edition-keywords-2015-2018-parsing.rs:17:35
    |
 LL |     r#async = consumes_async_raw!(async);
diff --git a/tests/ui/editions/edition-keywords-2018-2015-parsing.rs b/tests/ui/editions/edition-keywords-2018-2015-parsing.rs
index 5918454327409..c346be5085601 100644
--- a/tests/ui/editions/edition-keywords-2018-2015-parsing.rs
+++ b/tests/ui/editions/edition-keywords-2018-2015-parsing.rs
@@ -17,8 +17,8 @@ pub fn check_async() {
     let mut r#async = 1; // OK
 
     r#async = consumes_async!(async); // OK
-    r#async = consumes_async!(r#async); //~ ERROR no rules expected the token `r#async`
-    r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
+    r#async = consumes_async!(r#async); //~ ERROR no rules expected `r#async`
+    r#async = consumes_async_raw!(async); //~ ERROR no rules expected keyword `async`
     r#async = consumes_async_raw!(r#async); // OK
 
     if passes_ident!(async) == 1 {} // FIXME: Edition hygiene bug, async here is 2018 and reserved
diff --git a/tests/ui/editions/edition-keywords-2018-2015-parsing.stderr b/tests/ui/editions/edition-keywords-2018-2015-parsing.stderr
index 42db75f665973..aed5837abeafe 100644
--- a/tests/ui/editions/edition-keywords-2018-2015-parsing.stderr
+++ b/tests/ui/editions/edition-keywords-2018-2015-parsing.stderr
@@ -20,19 +20,19 @@ help: escape `async` to use it as an identifier
 LL |     module::r#async();
    |             ++
 
-error: no rules expected the token `r#async`
+error: no rules expected `r#async`
   --> $DIR/edition-keywords-2018-2015-parsing.rs:20:31
    |
 LL |     r#async = consumes_async!(r#async);
    |                               ^^^^^^^ no rules expected this token in macro call
    |
-note: while trying to match `async`
+note: while trying to match keyword `async`
   --> $DIR/auxiliary/edition-kw-macro-2015.rs:17:6
    |
 LL |     (async) => (1)
    |      ^^^^^
 
-error: no rules expected the token `async`
+error: no rules expected keyword `async`
   --> $DIR/edition-keywords-2018-2015-parsing.rs:21:35
    |
 LL |     r#async = consumes_async_raw!(async);
diff --git a/tests/ui/editions/edition-keywords-2018-2018-parsing.rs b/tests/ui/editions/edition-keywords-2018-2018-parsing.rs
index 4975246fa9423..b75b68b3febbd 100644
--- a/tests/ui/editions/edition-keywords-2018-2018-parsing.rs
+++ b/tests/ui/editions/edition-keywords-2018-2018-parsing.rs
@@ -24,8 +24,8 @@ pub fn check_async() {
     let mut r#async = 1; // OK
 
     r#async = consumes_async!(async); // OK
-    r#async = consumes_async!(r#async); //~ ERROR no rules expected the token `r#async`
-    r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
+    r#async = consumes_async!(r#async); //~ ERROR no rules expected `r#async`
+    r#async = consumes_async_raw!(async); //~ ERROR no rules expected keyword `async`
     r#async = consumes_async_raw!(r#async); // OK
 
     if passes_ident!(async) == 1 {} // FIXME: Edition hygiene bug, async here is 2018 and reserved
diff --git a/tests/ui/editions/edition-keywords-2018-2018-parsing.stderr b/tests/ui/editions/edition-keywords-2018-2018-parsing.stderr
index 4bbe1597233cf..6503e9cc73cf1 100644
--- a/tests/ui/editions/edition-keywords-2018-2018-parsing.stderr
+++ b/tests/ui/editions/edition-keywords-2018-2018-parsing.stderr
@@ -20,19 +20,19 @@ help: escape `async` to use it as an identifier
 LL |     module::r#async();
    |             ++
 
-error: no rules expected the token `r#async`
+error: no rules expected `r#async`
   --> $DIR/edition-keywords-2018-2018-parsing.rs:27:31
    |
 LL |     r#async = consumes_async!(r#async);
    |                               ^^^^^^^ no rules expected this token in macro call
    |
-note: while trying to match `async`
+note: while trying to match keyword `async`
   --> $DIR/auxiliary/edition-kw-macro-2018.rs:17:6
    |
 LL |     (async) => (1)
    |      ^^^^^
 
-error: no rules expected the token `async`
+error: no rules expected keyword `async`
   --> $DIR/edition-keywords-2018-2018-parsing.rs:28:35
    |
 LL |     r#async = consumes_async_raw!(async);
diff --git a/tests/ui/fail-simple.rs b/tests/ui/fail-simple.rs
index cd81a5d0a0fc6..55e547ee72b0f 100644
--- a/tests/ui/fail-simple.rs
+++ b/tests/ui/fail-simple.rs
@@ -1,3 +1,3 @@
 fn main() {
-    panic!(@); //~ ERROR no rules expected the token `@`
+    panic!(@); //~ ERROR no rules expected `@`
 }
diff --git a/tests/ui/fail-simple.stderr b/tests/ui/fail-simple.stderr
index 39fec3e2517b2..50c350b3ef55e 100644
--- a/tests/ui/fail-simple.stderr
+++ b/tests/ui/fail-simple.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `@`
+error: no rules expected `@`
   --> $DIR/fail-simple.rs:2:12
    |
 LL |     panic!(@);
diff --git a/tests/ui/layout/debug.stderr b/tests/ui/layout/debug.stderr
index c9715a8e14632..bd31665dac1f7 100644
--- a/tests/ui/layout/debug.stderr
+++ b/tests/ui/layout/debug.stderr
@@ -10,7 +10,7 @@ error: layout_of(E) = Layout {
                abi: Align(4 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -48,7 +48,7 @@ error: layout_of(E) = Layout {
                            abi: Align(1 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -150,7 +150,7 @@ error: layout_of(U) = Layout {
                abi: Align(4 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -337,7 +337,7 @@ error: layout_of(V) = Layout {
                abi: Align(2 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -361,7 +361,7 @@ error: layout_of(W) = Layout {
                abi: Align(2 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -385,7 +385,7 @@ error: layout_of(Y) = Layout {
                abi: Align(2 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -409,7 +409,7 @@ error: layout_of(P1) = Layout {
                abi: Align(1 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -433,7 +433,7 @@ error: layout_of(P2) = Layout {
                abi: Align(1 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -457,7 +457,7 @@ error: layout_of(P3) = Layout {
                abi: Align(1 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
@@ -481,7 +481,7 @@ error: layout_of(P4) = Layout {
                abi: Align(1 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Union(
diff --git a/tests/ui/layout/enum-scalar-pair-int-ptr.rs b/tests/ui/layout/enum-scalar-pair-int-ptr.rs
index 885cc3e37dfd6..ebb3fdb1514c3 100644
--- a/tests/ui/layout/enum-scalar-pair-int-ptr.rs
+++ b/tests/ui/layout/enum-scalar-pair-int-ptr.rs
@@ -18,7 +18,7 @@ enum ScalarPairPointerWithInt { //~ERROR: abi: ScalarPair
 // of a different size. (Assumes that no target has 8 bit pointers, which
 // feels pretty safe.)
 #[rustc_layout(abi)]
-enum NotScalarPairPointerWithSmallerInt { //~ERROR: abi: Aggregate
+enum NotScalarPairPointerWithSmallerInt { //~ERROR: abi: Memory
     A(u8),
     B(Box<()>),
 }
diff --git a/tests/ui/layout/enum-scalar-pair-int-ptr.stderr b/tests/ui/layout/enum-scalar-pair-int-ptr.stderr
index b25eda628cd6a..357c8182ebd6f 100644
--- a/tests/ui/layout/enum-scalar-pair-int-ptr.stderr
+++ b/tests/ui/layout/enum-scalar-pair-int-ptr.stderr
@@ -4,7 +4,7 @@ error: abi: ScalarPair(Initialized { value: Int(I?, false), valid_range: $VALID_
 LL | enum ScalarPairPointerWithInt {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: abi: Aggregate { sized: true }
+error: abi: Memory { sized: true }
   --> $DIR/enum-scalar-pair-int-ptr.rs:21:1
    |
 LL | enum NotScalarPairPointerWithSmallerInt {
diff --git a/tests/ui/layout/hexagon-enum.stderr b/tests/ui/layout/hexagon-enum.stderr
index a2ad4a1ab58ad..59fe667923f11 100644
--- a/tests/ui/layout/hexagon-enum.stderr
+++ b/tests/ui/layout/hexagon-enum.stderr
@@ -48,7 +48,7 @@ error: layout_of(A) = Layout {
                            abi: Align(1 bytes),
                            pref: Align(1 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -122,7 +122,7 @@ error: layout_of(B) = Layout {
                            abi: Align(1 bytes),
                            pref: Align(1 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -196,7 +196,7 @@ error: layout_of(C) = Layout {
                            abi: Align(2 bytes),
                            pref: Align(2 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -270,7 +270,7 @@ error: layout_of(P) = Layout {
                            abi: Align(4 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -344,7 +344,7 @@ error: layout_of(T) = Layout {
                            abi: Align(4 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/layout/issue-96158-scalarpair-payload-might-be-uninit.stderr b/tests/ui/layout/issue-96158-scalarpair-payload-might-be-uninit.stderr
index d3ba1a295b1bc..ca041fb539b93 100644
--- a/tests/ui/layout/issue-96158-scalarpair-payload-might-be-uninit.stderr
+++ b/tests/ui/layout/issue-96158-scalarpair-payload-might-be-uninit.stderr
@@ -90,7 +90,7 @@ error: layout_of(MissingPayloadField) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -489,7 +489,7 @@ error: layout_of(NicheFirst) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -509,7 +509,7 @@ error: layout_of(NicheFirst) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -641,7 +641,7 @@ error: layout_of(NicheSecond) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -661,7 +661,7 @@ error: layout_of(NicheSecond) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/layout/issue-96185-overaligned-enum.stderr b/tests/ui/layout/issue-96185-overaligned-enum.stderr
index c539eb453d915..bc40a2aa482ed 100644
--- a/tests/ui/layout/issue-96185-overaligned-enum.stderr
+++ b/tests/ui/layout/issue-96185-overaligned-enum.stderr
@@ -4,7 +4,7 @@ error: layout_of(Aligned1) = Layout {
                abi: Align(8 bytes),
                pref: $PREF_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -42,7 +42,7 @@ error: layout_of(Aligned1) = Layout {
                            abi: Align(8 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -64,7 +64,7 @@ error: layout_of(Aligned1) = Layout {
                            abi: Align(8 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -142,7 +142,7 @@ error: layout_of(Aligned2) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -164,7 +164,7 @@ error: layout_of(Aligned2) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/layout/struct.rs b/tests/ui/layout/struct.rs
index d072d123b0d4a..309624e667cc9 100644
--- a/tests/ui/layout/struct.rs
+++ b/tests/ui/layout/struct.rs
@@ -6,7 +6,7 @@
 #![crate_type = "lib"]
 
 #[rustc_layout(abi)]
-struct AlignedZstPreventsScalar(i16, [i32; 0]); //~ERROR: abi: Aggregate
+struct AlignedZstPreventsScalar(i16, [i32; 0]); //~ERROR: abi: Memory
 
 #[rustc_layout(abi)]
 struct AlignedZstButStillScalar(i32, [i16; 0]); //~ERROR: abi: Scalar
diff --git a/tests/ui/layout/struct.stderr b/tests/ui/layout/struct.stderr
index b61c9a99cce6a..7bc9af61ed48e 100644
--- a/tests/ui/layout/struct.stderr
+++ b/tests/ui/layout/struct.stderr
@@ -1,4 +1,4 @@
-error: abi: Aggregate { sized: true }
+error: abi: Memory { sized: true }
   --> $DIR/struct.rs:9:1
    |
 LL | struct AlignedZstPreventsScalar(i16, [i32; 0]);
diff --git a/tests/ui/layout/thumb-enum.stderr b/tests/ui/layout/thumb-enum.stderr
index 6f6ab49820676..bf043af586b1c 100644
--- a/tests/ui/layout/thumb-enum.stderr
+++ b/tests/ui/layout/thumb-enum.stderr
@@ -48,7 +48,7 @@ error: layout_of(A) = Layout {
                            abi: Align(1 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -122,7 +122,7 @@ error: layout_of(B) = Layout {
                            abi: Align(1 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -196,7 +196,7 @@ error: layout_of(C) = Layout {
                            abi: Align(2 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -270,7 +270,7 @@ error: layout_of(P) = Layout {
                            abi: Align(4 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -344,7 +344,7 @@ error: layout_of(T) = Layout {
                            abi: Align(4 bytes),
                            pref: Align(4 bytes),
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/layout/zero-sized-array-enum-niche.stderr b/tests/ui/layout/zero-sized-array-enum-niche.stderr
index ee34cfdfb0db0..d61408098df7f 100644
--- a/tests/ui/layout/zero-sized-array-enum-niche.stderr
+++ b/tests/ui/layout/zero-sized-array-enum-niche.stderr
@@ -4,7 +4,7 @@ error: layout_of(Result<[u32; 0], bool>) = Layout {
                abi: Align(4 bytes),
                pref: $PREF_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -42,7 +42,7 @@ error: layout_of(Result<[u32; 0], bool>) = Layout {
                            abi: Align(4 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -66,7 +66,7 @@ error: layout_of(Result<[u32; 0], bool>) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -109,7 +109,7 @@ error: layout_of(MultipleAlignments) = Layout {
                abi: Align(4 bytes),
                pref: $PREF_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -147,7 +147,7 @@ error: layout_of(MultipleAlignments) = Layout {
                            abi: Align(2 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -171,7 +171,7 @@ error: layout_of(MultipleAlignments) = Layout {
                            abi: Align(4 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -195,7 +195,7 @@ error: layout_of(MultipleAlignments) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -238,7 +238,7 @@ error: layout_of(Result<[u32; 0], Packed<NonZero<u16>>>) = Layout {
                abi: Align(4 bytes),
                pref: $PREF_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -276,7 +276,7 @@ error: layout_of(Result<[u32; 0], Packed<NonZero<u16>>>) = Layout {
                            abi: Align(4 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -300,7 +300,7 @@ error: layout_of(Result<[u32; 0], Packed<NonZero<u16>>>) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -343,7 +343,7 @@ error: layout_of(Result<[u32; 0], Packed<U16IsZero>>) = Layout {
                abi: Align(4 bytes),
                pref: $PREF_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -385,7 +385,7 @@ error: layout_of(Result<[u32; 0], Packed<U16IsZero>>) = Layout {
                            abi: Align(4 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -409,7 +409,7 @@ error: layout_of(Result<[u32; 0], Packed<U16IsZero>>) = Layout {
                            abi: Align(1 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/macros/assert-trailing-junk.with-generic-asset.stderr b/tests/ui/macros/assert-trailing-junk.with-generic-asset.stderr
index 1e73320e43912..7582c8e8659bc 100644
--- a/tests/ui/macros/assert-trailing-junk.with-generic-asset.stderr
+++ b/tests/ui/macros/assert-trailing-junk.with-generic-asset.stderr
@@ -10,7 +10,7 @@ error: expected one of `,`, `.`, `?`, or an operator, found `some`
 LL |     assert!(true some extra junk);
    |                  ^^^^ expected one of `,`, `.`, `?`, or an operator
 
-error: no rules expected the token `blah`
+error: no rules expected `blah`
   --> $DIR/assert-trailing-junk.rs:15:30
    |
 LL |     assert!(true, "whatever" blah);
@@ -28,7 +28,7 @@ LL |     assert!(true "whatever" blah);
    |                 |
    |                 help: try adding a comma
 
-error: no rules expected the token `blah`
+error: no rules expected `blah`
   --> $DIR/assert-trailing-junk.rs:18:29
    |
 LL |     assert!(true "whatever" blah);
diff --git a/tests/ui/macros/assert-trailing-junk.without-generic-asset.stderr b/tests/ui/macros/assert-trailing-junk.without-generic-asset.stderr
index 1e73320e43912..7582c8e8659bc 100644
--- a/tests/ui/macros/assert-trailing-junk.without-generic-asset.stderr
+++ b/tests/ui/macros/assert-trailing-junk.without-generic-asset.stderr
@@ -10,7 +10,7 @@ error: expected one of `,`, `.`, `?`, or an operator, found `some`
 LL |     assert!(true some extra junk);
    |                  ^^^^ expected one of `,`, `.`, `?`, or an operator
 
-error: no rules expected the token `blah`
+error: no rules expected `blah`
   --> $DIR/assert-trailing-junk.rs:15:30
    |
 LL |     assert!(true, "whatever" blah);
@@ -28,7 +28,7 @@ LL |     assert!(true "whatever" blah);
    |                 |
    |                 help: try adding a comma
 
-error: no rules expected the token `blah`
+error: no rules expected `blah`
   --> $DIR/assert-trailing-junk.rs:18:29
    |
 LL |     assert!(true "whatever" blah);
diff --git a/tests/ui/macros/best-failure.rs b/tests/ui/macros/best-failure.rs
index bbdd465d5ec96..1b73066c8749d 100644
--- a/tests/ui/macros/best-failure.rs
+++ b/tests/ui/macros/best-failure.rs
@@ -2,7 +2,7 @@ macro_rules! number {
     (neg false, $self:ident) => { $self };
     ($signed:tt => $ty:ty;) => {
         number!(neg $signed, $self);
-        //~^ ERROR no rules expected the token `$`
+        //~^ ERROR no rules expected `$`
     };
 }
 
diff --git a/tests/ui/macros/best-failure.stderr b/tests/ui/macros/best-failure.stderr
index c5f8b9abc19a1..914ff7fd8207f 100644
--- a/tests/ui/macros/best-failure.stderr
+++ b/tests/ui/macros/best-failure.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `$`
+error: no rules expected `$`
   --> $DIR/best-failure.rs:4:30
    |
 LL | macro_rules! number {
diff --git a/tests/ui/macros/expr_2021_inline_const.edi2021.stderr b/tests/ui/macros/expr_2021_inline_const.edi2021.stderr
index 22d662aaaf2f9..bf7eb3888b33e 100644
--- a/tests/ui/macros/expr_2021_inline_const.edi2021.stderr
+++ b/tests/ui/macros/expr_2021_inline_const.edi2021.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `const`
+error: no rules expected keyword `const`
   --> $DIR/expr_2021_inline_const.rs:23:12
    |
 LL | macro_rules! m2021 {
@@ -13,7 +13,7 @@ note: while trying to match meta-variable `$e:expr_2021`
 LL |     ($e:expr_2021) => {
    |      ^^^^^^^^^^^^
 
-error: no rules expected the token `const`
+error: no rules expected keyword `const`
   --> $DIR/expr_2021_inline_const.rs:24:12
    |
 LL | macro_rules! m2024 {
diff --git a/tests/ui/macros/expr_2021_inline_const.edi2024.stderr b/tests/ui/macros/expr_2021_inline_const.edi2024.stderr
index 2555e4f757a52..1028ddc4267fc 100644
--- a/tests/ui/macros/expr_2021_inline_const.edi2024.stderr
+++ b/tests/ui/macros/expr_2021_inline_const.edi2024.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `const`
+error: no rules expected keyword `const`
   --> $DIR/expr_2021_inline_const.rs:23:12
    |
 LL | macro_rules! m2021 {
diff --git a/tests/ui/macros/expr_2021_inline_const.rs b/tests/ui/macros/expr_2021_inline_const.rs
index 39a542fe4d94a..312256f1879c3 100644
--- a/tests/ui/macros/expr_2021_inline_const.rs
+++ b/tests/ui/macros/expr_2021_inline_const.rs
@@ -20,8 +20,8 @@ macro_rules! test {
 }
 
 fn main() {
-    m2021!(const { 1 }); //~ ERROR: no rules expected the token `const`
-    m2024!(const { 1 }); //[edi2021]~ ERROR: no rules expected the token `const`
+    m2021!(const { 1 }); //~ ERROR: no rules expected keyword `const`
+    m2024!(const { 1 }); //[edi2021]~ ERROR: no rules expected keyword `const`
 
     test!(expr);
 }
diff --git a/tests/ui/macros/expr_2024_underscore_expr.edi2021.stderr b/tests/ui/macros/expr_2024_underscore_expr.edi2021.stderr
index 34df20a69ef51..7b3ca54bb7132 100644
--- a/tests/ui/macros/expr_2024_underscore_expr.edi2021.stderr
+++ b/tests/ui/macros/expr_2024_underscore_expr.edi2021.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `_`
+error: no rules expected reserved identifier `_`
   --> $DIR/expr_2024_underscore_expr.rs:19:12
    |
 LL | macro_rules! m2021 {
@@ -13,7 +13,7 @@ note: while trying to match meta-variable `$e:expr_2021`
 LL |     ($e:expr_2021) => {
    |      ^^^^^^^^^^^^
 
-error: no rules expected the token `_`
+error: no rules expected reserved identifier `_`
   --> $DIR/expr_2024_underscore_expr.rs:20:12
    |
 LL | macro_rules! m2024 {
diff --git a/tests/ui/macros/expr_2024_underscore_expr.edi2024.stderr b/tests/ui/macros/expr_2024_underscore_expr.edi2024.stderr
index 372c5d8637c9f..59104dafa1816 100644
--- a/tests/ui/macros/expr_2024_underscore_expr.edi2024.stderr
+++ b/tests/ui/macros/expr_2024_underscore_expr.edi2024.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `_`
+error: no rules expected reserved identifier `_`
   --> $DIR/expr_2024_underscore_expr.rs:19:12
    |
 LL | macro_rules! m2021 {
diff --git a/tests/ui/macros/expr_2024_underscore_expr.rs b/tests/ui/macros/expr_2024_underscore_expr.rs
index 86e3137450685..6f8ec139109bb 100644
--- a/tests/ui/macros/expr_2024_underscore_expr.rs
+++ b/tests/ui/macros/expr_2024_underscore_expr.rs
@@ -16,6 +16,6 @@ macro_rules! m2024 {
 }
 
 fn main() {
-    m2021!(_); //~ ERROR: no rules expected the token `_`
-    m2024!(_); //[edi2021]~ ERROR: no rules expected the token `_`
+    m2021!(_); //~ ERROR: no rules expected reserved identifier `_`
+    m2024!(_); //[edi2021]~ ERROR: no rules expected reserved identifier `_`
 }
diff --git a/tests/ui/macros/issue-118786.rs b/tests/ui/macros/issue-118786.rs
index a41372e4ea840..a73b737fe07e4 100644
--- a/tests/ui/macros/issue-118786.rs
+++ b/tests/ui/macros/issue-118786.rs
@@ -5,7 +5,7 @@
 macro_rules! make_macro {
     ($macro_name:tt) => {
         macro_rules! $macro_name {
-        //~^ ERROR macro expansion ignores token `{` and any following
+        //~^ ERROR macro expansion ignores `{` and any tokens following
         //~| ERROR cannot find macro `macro_rules` in this scope
         //~| put a macro name here
             () => {}
diff --git a/tests/ui/macros/issue-118786.stderr b/tests/ui/macros/issue-118786.stderr
index 256b742ee160b..7fa5c2b83ddd8 100644
--- a/tests/ui/macros/issue-118786.stderr
+++ b/tests/ui/macros/issue-118786.stderr
@@ -13,7 +13,7 @@ help: add a semicolon
 LL |         macro_rules! $macro_name; {
    |                                 +
 
-error: macro expansion ignores token `{` and any following
+error: macro expansion ignores `{` and any tokens following
   --> $DIR/issue-118786.rs:7:34
    |
 LL |         macro_rules! $macro_name {
diff --git a/tests/ui/macros/issue-30007.rs b/tests/ui/macros/issue-30007.rs
index 918a821bae925..e36e47a3e7c23 100644
--- a/tests/ui/macros/issue-30007.rs
+++ b/tests/ui/macros/issue-30007.rs
@@ -1,5 +1,5 @@
 macro_rules! t {
-    () => ( String ; );     //~ ERROR macro expansion ignores token `;`
+    () => ( String ; );     //~ ERROR macro expansion ignores `;`
 }
 
 fn main() {
diff --git a/tests/ui/macros/issue-30007.stderr b/tests/ui/macros/issue-30007.stderr
index f303221cf8aa8..129733ed69aba 100644
--- a/tests/ui/macros/issue-30007.stderr
+++ b/tests/ui/macros/issue-30007.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `;` and any following
+error: macro expansion ignores `;` and any tokens following
   --> $DIR/issue-30007.rs:2:20
    |
 LL |     () => ( String ; );
diff --git a/tests/ui/macros/issue-54441.rs b/tests/ui/macros/issue-54441.rs
index b24d7e1f6bee5..37ab4e636475b 100644
--- a/tests/ui/macros/issue-54441.rs
+++ b/tests/ui/macros/issue-54441.rs
@@ -1,6 +1,6 @@
 macro_rules! m {
     () => {
-        let //~ ERROR macro expansion ignores token `let` and any following
+        let //~ ERROR macro expansion ignores keyword `let` and any tokens following
     };
 }
 
diff --git a/tests/ui/macros/issue-54441.stderr b/tests/ui/macros/issue-54441.stderr
index fb2c103139b97..f5f8b8ca2b266 100644
--- a/tests/ui/macros/issue-54441.stderr
+++ b/tests/ui/macros/issue-54441.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `let` and any following
+error: macro expansion ignores keyword `let` and any tokens following
   --> $DIR/issue-54441.rs:3:9
    |
 LL |         let
diff --git a/tests/ui/macros/macro-at-most-once-rep-2015.rs b/tests/ui/macros/macro-at-most-once-rep-2015.rs
index 8f2531a25aeaf..08967b82531c9 100644
--- a/tests/ui/macros/macro-at-most-once-rep-2015.rs
+++ b/tests/ui/macros/macro-at-most-once-rep-2015.rs
@@ -22,21 +22,21 @@ macro_rules! barstar {
 pub fn main() {
     foo!();
     foo!(a);
-    foo!(a?); //~ ERROR no rules expected the token `?`
-    foo!(a?a); //~ ERROR no rules expected the token `?`
-    foo!(a?a?a); //~ ERROR no rules expected the token `?`
+    foo!(a?); //~ ERROR no rules expected `?`
+    foo!(a?a); //~ ERROR no rules expected `?`
+    foo!(a?a?a); //~ ERROR no rules expected `?`
 
     barplus!(); //~ERROR unexpected end of macro invocation
     barplus!(a); //~ERROR unexpected end of macro invocation
-    barplus!(a?); //~ ERROR no rules expected the token `?`
-    barplus!(a?a); //~ ERROR no rules expected the token `?`
+    barplus!(a?); //~ ERROR no rules expected `?`
+    barplus!(a?a); //~ ERROR no rules expected `?`
     barplus!(a+);
     barplus!(+);
 
     barstar!(); //~ERROR unexpected end of macro invocation
     barstar!(a); //~ERROR unexpected end of macro invocation
-    barstar!(a?); //~ ERROR no rules expected the token `?`
-    barstar!(a?a); //~ ERROR no rules expected the token `?`
+    barstar!(a?); //~ ERROR no rules expected `?`
+    barstar!(a?a); //~ ERROR no rules expected `?`
     barstar!(a*);
     barstar!(*);
 }
diff --git a/tests/ui/macros/macro-at-most-once-rep-2015.stderr b/tests/ui/macros/macro-at-most-once-rep-2015.stderr
index 7c45b85bc8d4e..7f161cdc8d0b4 100644
--- a/tests/ui/macros/macro-at-most-once-rep-2015.stderr
+++ b/tests/ui/macros/macro-at-most-once-rep-2015.stderr
@@ -4,7 +4,7 @@ error: the `?` macro repetition operator does not take a separator
 LL |     ($(a),?) => {};
    |          ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:25:11
    |
 LL | macro_rules! foo {
@@ -15,7 +15,7 @@ LL |     foo!(a?);
    |
    = note: while trying to match sequence end
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:26:11
    |
 LL | macro_rules! foo {
@@ -26,7 +26,7 @@ LL |     foo!(a?a);
    |
    = note: while trying to match sequence end
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:27:11
    |
 LL | macro_rules! foo {
@@ -67,7 +67,7 @@ note: while trying to match `+`
 LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:31:15
    |
 LL | macro_rules! barplus {
@@ -82,7 +82,7 @@ note: while trying to match `+`
 LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:32:15
    |
 LL | macro_rules! barplus {
@@ -127,7 +127,7 @@ note: while trying to match `*`
 LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:38:15
    |
 LL | macro_rules! barstar {
@@ -142,7 +142,7 @@ note: while trying to match `*`
 LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:39:15
    |
 LL | macro_rules! barstar {
diff --git a/tests/ui/macros/macro-at-most-once-rep-2018.rs b/tests/ui/macros/macro-at-most-once-rep-2018.rs
index 7f43055ded6f4..98fbb2ad20733 100644
--- a/tests/ui/macros/macro-at-most-once-rep-2018.rs
+++ b/tests/ui/macros/macro-at-most-once-rep-2018.rs
@@ -22,21 +22,21 @@ macro_rules! barstar {
 pub fn main() {
     foo!();
     foo!(a);
-    foo!(a?); //~ ERROR no rules expected the token `?`
-    foo!(a?a); //~ ERROR no rules expected the token `?`
-    foo!(a?a?a); //~ ERROR no rules expected the token `?`
+    foo!(a?); //~ ERROR no rules expected `?`
+    foo!(a?a); //~ ERROR no rules expected `?`
+    foo!(a?a?a); //~ ERROR no rules expected `?`
 
     barplus!(); //~ERROR unexpected end of macro invocation
     barplus!(a); //~ERROR unexpected end of macro invocation
-    barplus!(a?); //~ ERROR no rules expected the token `?`
-    barplus!(a?a); //~ ERROR no rules expected the token `?`
+    barplus!(a?); //~ ERROR no rules expected `?`
+    barplus!(a?a); //~ ERROR no rules expected `?`
     barplus!(a+);
     barplus!(+);
 
     barstar!(); //~ERROR unexpected end of macro invocation
     barstar!(a); //~ERROR unexpected end of macro invocation
-    barstar!(a?); //~ ERROR no rules expected the token `?`
-    barstar!(a?a); //~ ERROR no rules expected the token `?`
+    barstar!(a?); //~ ERROR no rules expected `?`
+    barstar!(a?a); //~ ERROR no rules expected `?`
     barstar!(a*);
     barstar!(*);
 }
diff --git a/tests/ui/macros/macro-at-most-once-rep-2018.stderr b/tests/ui/macros/macro-at-most-once-rep-2018.stderr
index 696520b28268a..f165a199b10b9 100644
--- a/tests/ui/macros/macro-at-most-once-rep-2018.stderr
+++ b/tests/ui/macros/macro-at-most-once-rep-2018.stderr
@@ -4,7 +4,7 @@ error: the `?` macro repetition operator does not take a separator
 LL |     ($(a),?) => {};
    |          ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:25:11
    |
 LL | macro_rules! foo {
@@ -15,7 +15,7 @@ LL |     foo!(a?);
    |
    = note: while trying to match sequence end
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:26:11
    |
 LL | macro_rules! foo {
@@ -26,7 +26,7 @@ LL |     foo!(a?a);
    |
    = note: while trying to match sequence end
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:27:11
    |
 LL | macro_rules! foo {
@@ -67,7 +67,7 @@ note: while trying to match `+`
 LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:31:15
    |
 LL | macro_rules! barplus {
@@ -82,7 +82,7 @@ note: while trying to match `+`
 LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:32:15
    |
 LL | macro_rules! barplus {
@@ -127,7 +127,7 @@ note: while trying to match `*`
 LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:38:15
    |
 LL | macro_rules! barstar {
@@ -142,7 +142,7 @@ note: while trying to match `*`
 LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
    |           ^
 
-error: no rules expected the token `?`
+error: no rules expected `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:39:15
    |
 LL | macro_rules! barstar {
diff --git a/tests/ui/macros/macro-context.rs b/tests/ui/macros/macro-context.rs
index d09fdf118e6f4..a31470263a0a5 100644
--- a/tests/ui/macros/macro-context.rs
+++ b/tests/ui/macros/macro-context.rs
@@ -1,9 +1,9 @@
 // (typeof used because it's surprisingly hard to find an unparsed token after a stmt)
 macro_rules! m {
     () => ( i ; typeof );   //~ ERROR expected expression, found reserved keyword `typeof`
-                            //~| ERROR macro expansion ignores token `typeof`
-                            //~| ERROR macro expansion ignores token `;`
-                            //~| ERROR macro expansion ignores token `;`
+                            //~| ERROR macro expansion ignores reserved keyword `typeof`
+                            //~| ERROR macro expansion ignores `;`
+                            //~| ERROR macro expansion ignores `;`
                             //~| ERROR cannot find type `i` in this scope
                             //~| ERROR cannot find value `i` in this scope
                             //~| WARN trailing semicolon in macro
diff --git a/tests/ui/macros/macro-context.stderr b/tests/ui/macros/macro-context.stderr
index 7785f41594627..4820a43f00c79 100644
--- a/tests/ui/macros/macro-context.stderr
+++ b/tests/ui/macros/macro-context.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `;` and any following
+error: macro expansion ignores `;` and any tokens following
   --> $DIR/macro-context.rs:3:15
    |
 LL |     () => ( i ; typeof );
@@ -9,7 +9,7 @@ LL |     let a: m!();
    |
    = note: the usage of `m!` is likely invalid in type context
 
-error: macro expansion ignores token `typeof` and any following
+error: macro expansion ignores reserved keyword `typeof` and any tokens following
   --> $DIR/macro-context.rs:3:17
    |
 LL |     () => ( i ; typeof );
@@ -20,7 +20,7 @@ LL |     let i = m!();
    |
    = note: the usage of `m!` is likely invalid in expression context
 
-error: macro expansion ignores token `;` and any following
+error: macro expansion ignores `;` and any tokens following
   --> $DIR/macro-context.rs:3:15
    |
 LL |     () => ( i ; typeof );
diff --git a/tests/ui/macros/macro-in-expression-context.fixed b/tests/ui/macros/macro-in-expression-context.fixed
index f4d04ca37bf5b..7c830707ffd9d 100644
--- a/tests/ui/macros/macro-in-expression-context.fixed
+++ b/tests/ui/macros/macro-in-expression-context.fixed
@@ -11,7 +11,7 @@ macro_rules! foo {
         //~| NOTE `#[warn(semicolon_in_expressions_from_macros)]` on by default
         assert_eq!("B", "B");
     }
-    //~^^ ERROR macro expansion ignores token `assert_eq` and any following
+    //~^^ ERROR macro expansion ignores `assert_eq` and any tokens following
     //~| NOTE the usage of `foo!` is likely invalid in expression context
 }
 
diff --git a/tests/ui/macros/macro-in-expression-context.rs b/tests/ui/macros/macro-in-expression-context.rs
index 8921a05637725..da95017aa5f74 100644
--- a/tests/ui/macros/macro-in-expression-context.rs
+++ b/tests/ui/macros/macro-in-expression-context.rs
@@ -11,7 +11,7 @@ macro_rules! foo {
         //~| NOTE `#[warn(semicolon_in_expressions_from_macros)]` on by default
         assert_eq!("B", "B");
     }
-    //~^^ ERROR macro expansion ignores token `assert_eq` and any following
+    //~^^ ERROR macro expansion ignores `assert_eq` and any tokens following
     //~| NOTE the usage of `foo!` is likely invalid in expression context
 }
 
diff --git a/tests/ui/macros/macro-in-expression-context.stderr b/tests/ui/macros/macro-in-expression-context.stderr
index 2eee63f307af9..43419f2678c22 100644
--- a/tests/ui/macros/macro-in-expression-context.stderr
+++ b/tests/ui/macros/macro-in-expression-context.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `assert_eq` and any following
+error: macro expansion ignores `assert_eq` and any tokens following
   --> $DIR/macro-in-expression-context.rs:12:9
    |
 LL |         assert_eq!("B", "B");
diff --git a/tests/ui/macros/macro-non-lifetime.rs b/tests/ui/macros/macro-non-lifetime.rs
index 26e1f2afa91bb..3defffd29604a 100644
--- a/tests/ui/macros/macro-non-lifetime.rs
+++ b/tests/ui/macros/macro-non-lifetime.rs
@@ -4,5 +4,5 @@ macro_rules! m { ($x:lifetime) => { } }
 
 fn main() {
     m!(a);
-    //~^ ERROR no rules expected the token `a`
+    //~^ ERROR no rules expected `a`
 }
diff --git a/tests/ui/macros/macro-non-lifetime.stderr b/tests/ui/macros/macro-non-lifetime.stderr
index 9ff3d741c01d2..35040a2229bd3 100644
--- a/tests/ui/macros/macro-non-lifetime.stderr
+++ b/tests/ui/macros/macro-non-lifetime.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `a`
+error: no rules expected `a`
   --> $DIR/macro-non-lifetime.rs:6:8
    |
 LL | macro_rules! m { ($x:lifetime) => { } }
diff --git a/tests/ui/macros/missing-comma.rs b/tests/ui/macros/missing-comma.rs
index 92f8a77950583..64cfb0db31a0b 100644
--- a/tests/ui/macros/missing-comma.rs
+++ b/tests/ui/macros/missing-comma.rs
@@ -19,16 +19,16 @@ fn main() {
     println!("{}" a);
     //~^ ERROR expected `,`, found `a`
     foo!(a b);
-    //~^ ERROR no rules expected the token `b`
+    //~^ ERROR no rules expected `b`
     foo!(a, b, c, d e);
-    //~^ ERROR no rules expected the token `e`
+    //~^ ERROR no rules expected `e`
     foo!(a, b, c d, e);
-    //~^ ERROR no rules expected the token `d`
+    //~^ ERROR no rules expected `d`
     foo!(a, b, c d e);
-    //~^ ERROR no rules expected the token `d`
+    //~^ ERROR no rules expected `d`
     bar!(Level::Error, );
     //~^ ERROR unexpected end of macro invocation
     check!(<str as Debug>::fmt, "fmt");
     check!(<str as Debug>::fmt, "fmt",);
-    //~^ ERROR no rules expected the token `,`
+    //~^ ERROR no rules expected `,`
 }
diff --git a/tests/ui/macros/missing-comma.stderr b/tests/ui/macros/missing-comma.stderr
index 81877a29ed8ae..9913ba3491927 100644
--- a/tests/ui/macros/missing-comma.stderr
+++ b/tests/ui/macros/missing-comma.stderr
@@ -4,7 +4,7 @@ error: expected `,`, found `a`
 LL |     println!("{}" a);
    |                   ^ expected `,`
 
-error: no rules expected the token `b`
+error: no rules expected `b`
   --> $DIR/missing-comma.rs:21:12
    |
 LL | macro_rules! foo {
@@ -21,7 +21,7 @@ note: while trying to match meta-variable `$a:ident`
 LL |     ($a:ident) => ();
    |      ^^^^^^^^
 
-error: no rules expected the token `e`
+error: no rules expected `e`
   --> $DIR/missing-comma.rs:23:21
    |
 LL | macro_rules! foo {
@@ -38,7 +38,7 @@ note: while trying to match meta-variable `$d:ident`
 LL |     ($a:ident, $b:ident, $c:ident, $d:ident) => ();
    |                                    ^^^^^^^^
 
-error: no rules expected the token `d`
+error: no rules expected `d`
   --> $DIR/missing-comma.rs:25:18
    |
 LL | macro_rules! foo {
@@ -55,7 +55,7 @@ note: while trying to match meta-variable `$c:ident`
 LL |     ($a:ident, $b:ident, $c:ident) => ();
    |                          ^^^^^^^^
 
-error: no rules expected the token `d`
+error: no rules expected `d`
   --> $DIR/missing-comma.rs:27:18
    |
 LL | macro_rules! foo {
@@ -85,7 +85,7 @@ note: while trying to match meta-variable `$arg:tt`
 LL |     ($lvl:expr, $($arg:tt)+) => {}
    |                   ^^^^^^^
 
-error: no rules expected the token `,`
+error: no rules expected `,`
   --> $DIR/missing-comma.rs:32:38
    |
 LL | macro_rules! check {
diff --git a/tests/ui/macros/nonterminal-matching.rs b/tests/ui/macros/nonterminal-matching.rs
index 5f0d6b2f90eee..a655b66510311 100644
--- a/tests/ui/macros/nonterminal-matching.rs
+++ b/tests/ui/macros/nonterminal-matching.rs
@@ -16,7 +16,7 @@ macro complex_nonterminal($nt_item: item) {
         struct S;
     }
 
-    n!(a $nt_item b); //~ ERROR no rules expected the token `enum E {}`
+    n!(a $nt_item b); //~ ERROR no rules expected item `enum E {}`
 }
 
 simple_nonterminal!(a, 'a, (x, y, z)); // OK
@@ -29,10 +29,10 @@ macro_rules! foo {
     (ident $x:ident) => { bar!(ident $x); };
     (lifetime $x:lifetime) => { bar!(lifetime $x); };
     (tt $x:tt) => { bar!(tt $x); };
-    (expr $x:expr) => { bar!(expr $x); }; //~ ERROR: no rules expected the token `3`
-    (literal $x:literal) => { bar!(literal $x); }; //~ ERROR: no rules expected the token `4`
-    (path $x:path) => { bar!(path $x); }; //~ ERROR: no rules expected the token `a::b::c`
-    (stmt $x:stmt) => { bar!(stmt $x); }; //~ ERROR: no rules expected the token `let abc = 0`
+    (expr $x:expr) => { bar!(expr $x); }; //~ ERROR: no rules expected expression `3`
+    (literal $x:literal) => { bar!(literal $x); }; //~ ERROR: no rules expected literal `4`
+    (path $x:path) => { bar!(path $x); }; //~ ERROR: no rules expected path `a::b::c`
+    (stmt $x:stmt) => { bar!(stmt $x); }; //~ ERROR: no rules expected statement `let abc = 0`
 }
 
 macro_rules! bar {
diff --git a/tests/ui/macros/nonterminal-matching.stderr b/tests/ui/macros/nonterminal-matching.stderr
index 3ee88b5f52ef9..e283dfcb8fdc4 100644
--- a/tests/ui/macros/nonterminal-matching.stderr
+++ b/tests/ui/macros/nonterminal-matching.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `enum E {}`
+error: no rules expected item `enum E {}`
   --> $DIR/nonterminal-matching.rs:19:10
    |
 LL |     macro n(a $nt_item b) {
@@ -10,7 +10,7 @@ LL |     n!(a $nt_item b);
 LL | complex_nonterminal!(enum E {});
    | ------------------------------- in this macro invocation
    |
-note: while trying to match `enum E {}`
+note: while trying to match item `enum E {}`
   --> $DIR/nonterminal-matching.rs:15:15
    |
 LL |     macro n(a $nt_item b) {
@@ -23,7 +23,7 @@ LL | complex_nonterminal!(enum E {});
    = help: try using `:tt` instead in the macro definition
    = note: this error originates in the macro `complex_nonterminal` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: no rules expected the token `3`
+error: no rules expected expression `3`
   --> $DIR/nonterminal-matching.rs:32:35
    |
 LL |     (expr $x:expr) => { bar!(expr $x); };
@@ -45,7 +45,7 @@ LL |     (expr 3) => {};
    = help: try using `:tt` instead in the macro definition
    = note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: no rules expected the token `4`
+error: no rules expected literal `4`
   --> $DIR/nonterminal-matching.rs:33:44
    |
 LL |     (literal $x:literal) => { bar!(literal $x); };
@@ -67,7 +67,7 @@ LL |     (literal 4) => {};
    = help: try using `:tt` instead in the macro definition
    = note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: no rules expected the token `a::b::c`
+error: no rules expected path `a::b::c`
   --> $DIR/nonterminal-matching.rs:34:35
    |
 LL |     (path $x:path) => { bar!(path $x); };
@@ -89,7 +89,7 @@ LL |     (path a::b::c) => {};
    = help: try using `:tt` instead in the macro definition
    = note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: no rules expected the token `let abc = 0`
+error: no rules expected statement `let abc = 0`
   --> $DIR/nonterminal-matching.rs:35:35
    |
 LL |     (stmt $x:stmt) => { bar!(stmt $x); };
@@ -101,7 +101,7 @@ LL | macro_rules! bar {
 LL | foo!(stmt let abc = 0);
    | ---------------------- in this macro invocation
    |
-note: while trying to match `let`
+note: while trying to match keyword `let`
   --> $DIR/nonterminal-matching.rs:45:11
    |
 LL |     (stmt let abc = 0) => {};
diff --git a/tests/ui/macros/syntax-error-recovery.rs b/tests/ui/macros/syntax-error-recovery.rs
index f6178c137db97..016e4def28497 100644
--- a/tests/ui/macros/syntax-error-recovery.rs
+++ b/tests/ui/macros/syntax-error-recovery.rs
@@ -10,7 +10,7 @@ macro_rules! values {
     };
 }
 //~^^^^^ ERROR expected one of `(`, `,`, `=`, `{`, or `}`, found type `(String)`
-//~| ERROR macro expansion ignores token `(String)` and any following
+//~| ERROR macro expansion ignores type `(String)` and any tokens following
 
 values!(STRING(1) as (String) => cfg(test),);
 //~^ ERROR expected one of `!` or `::`, found `<eof>`
diff --git a/tests/ui/macros/syntax-error-recovery.stderr b/tests/ui/macros/syntax-error-recovery.stderr
index 6218bf43a1ef2..3cfbd8ce82b56 100644
--- a/tests/ui/macros/syntax-error-recovery.stderr
+++ b/tests/ui/macros/syntax-error-recovery.stderr
@@ -10,7 +10,7 @@ LL | values!(STRING(1) as (String) => cfg(test),);
    = help: enum variants can be `Variant`, `Variant = <integer>`, `Variant(Type, ..., TypeN)` or `Variant { fields: Types }`
    = note: this error originates in the macro `values` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: macro expansion ignores token `(String)` and any following
+error: macro expansion ignores type `(String)` and any tokens following
   --> $DIR/syntax-error-recovery.rs:7:26
    |
 LL |                 $token $($inner)? = $value,
diff --git a/tests/ui/macros/trace_faulty_macros.stderr b/tests/ui/macros/trace_faulty_macros.stderr
index 66d7b76bb0726..10ad3faab1612 100644
--- a/tests/ui/macros/trace_faulty_macros.stderr
+++ b/tests/ui/macros/trace_faulty_macros.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `bcd`
+error: no rules expected `bcd`
   --> $DIR/trace_faulty_macros.rs:7:26
    |
 LL | macro_rules! my_faulty_macro {
diff --git a/tests/ui/offset-of/offset-of-arg-count.rs b/tests/ui/offset-of/offset-of-arg-count.rs
index c86e61a61a725..f4c8b91d7daee 100644
--- a/tests/ui/offset-of/offset-of-arg-count.rs
+++ b/tests/ui/offset-of/offset-of-arg-count.rs
@@ -3,7 +3,7 @@ use std::mem::offset_of;
 fn main() {
     offset_of!(NotEnoughArguments); //~ ERROR unexpected end of macro invocation
     offset_of!(NotEnoughArgumentsWithAComma, ); //~ ERROR unexpected end of macro invocation
-    offset_of!(Container, field, too many arguments); //~ ERROR no rules expected the token `too`
+    offset_of!(Container, field, too many arguments); //~ ERROR no rules expected `too`
     offset_of!(S, f); // compiles fine
     offset_of!(S, f,); // also compiles fine
     offset_of!(S, f.); //~ ERROR unexpected token: `)`
diff --git a/tests/ui/offset-of/offset-of-arg-count.stderr b/tests/ui/offset-of/offset-of-arg-count.stderr
index 4cb24b3d034b6..0772bb18e0c62 100644
--- a/tests/ui/offset-of/offset-of-arg-count.stderr
+++ b/tests/ui/offset-of/offset-of-arg-count.stderr
@@ -16,7 +16,7 @@ LL |     offset_of!(NotEnoughArgumentsWithAComma, );
 note: while trying to match meta-variable `$fields:expr`
   --> $SRC_DIR/core/src/mem/mod.rs:LL:COL
 
-error: no rules expected the token `too`
+error: no rules expected `too`
   --> $DIR/offset-of-arg-count.rs:6:34
    |
 LL |     offset_of!(Container, field, too many arguments);
diff --git a/tests/ui/offset-of/offset-of-tuple.stderr b/tests/ui/offset-of/offset-of-tuple.stderr
index dd20859e04e1b..38ce49c9179ba 100644
--- a/tests/ui/offset-of/offset-of-tuple.stderr
+++ b/tests/ui/offset-of/offset-of-tuple.stderr
@@ -76,7 +76,7 @@ error: suffixes on a tuple index are invalid
 LL |     offset_of!((u8, u8), 1_u8);
    |                          ^^^^ invalid suffix `u8`
 
-error: no rules expected the token `+`
+error: no rules expected `+`
   --> $DIR/offset-of-tuple.rs:11:26
    |
 LL |     offset_of!((u8, u8), +1);
diff --git a/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.rs b/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.rs
index 7a94c96b79d89..fb227bf0e915f 100644
--- a/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.rs
+++ b/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.rs
@@ -9,5 +9,5 @@ macro_rules! accept_pat {
     ($p:pat) => {};
 }
 
-accept_pat!(p | q); //~ ERROR no rules expected the token `|`
-accept_pat!(|p| q); //~ ERROR no rules expected the token `|`
+accept_pat!(p | q); //~ ERROR no rules expected `|`
+accept_pat!(|p| q); //~ ERROR no rules expected `|`
diff --git a/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr b/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr
index acc2099bbc6a8..47dac84ee4947 100644
--- a/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr
+++ b/tests/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `|`
+error: no rules expected `|`
   --> $DIR/or-patterns-syntactic-fail-2018.rs:12:15
    |
 LL | macro_rules! accept_pat {
@@ -13,7 +13,7 @@ note: while trying to match meta-variable `$p:pat`
 LL |     ($p:pat) => {};
    |      ^^^^^^
 
-error: no rules expected the token `|`
+error: no rules expected `|`
   --> $DIR/or-patterns-syntactic-fail-2018.rs:13:13
    |
 LL | macro_rules! accept_pat {
diff --git a/tests/ui/parser/macro/macro-doc-comments-1.rs b/tests/ui/parser/macro/macro-doc-comments-1.rs
index 8d8103bb1e065..1aaa993e0721d 100644
--- a/tests/ui/parser/macro/macro-doc-comments-1.rs
+++ b/tests/ui/parser/macro/macro-doc-comments-1.rs
@@ -4,6 +4,6 @@ macro_rules! outer {
 
 outer! {
     //! Inner
-} //~^ ERROR no rules expected the token `!`
+} //~^ ERROR no rules expected `!`
 
 fn main() { }
diff --git a/tests/ui/parser/macro/macro-doc-comments-1.stderr b/tests/ui/parser/macro/macro-doc-comments-1.stderr
index 9d2d1bc00725a..6b7e758980c2b 100644
--- a/tests/ui/parser/macro/macro-doc-comments-1.stderr
+++ b/tests/ui/parser/macro/macro-doc-comments-1.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `!`
+error: no rules expected `!`
   --> $DIR/macro-doc-comments-1.rs:6:5
    |
 LL | macro_rules! outer {
diff --git a/tests/ui/parser/macro/macro-doc-comments-2.rs b/tests/ui/parser/macro/macro-doc-comments-2.rs
index 8f33720ae80eb..2bee2435ef872 100644
--- a/tests/ui/parser/macro/macro-doc-comments-2.rs
+++ b/tests/ui/parser/macro/macro-doc-comments-2.rs
@@ -4,6 +4,6 @@ macro_rules! inner {
 
 inner! {
     /// Outer
-} //~^ ERROR no rules expected the token `[`
+} //~^ ERROR no rules expected `[`
 
 fn main() { }
diff --git a/tests/ui/parser/macro/macro-doc-comments-2.stderr b/tests/ui/parser/macro/macro-doc-comments-2.stderr
index 22efd995b463c..02c12bf959114 100644
--- a/tests/ui/parser/macro/macro-doc-comments-2.stderr
+++ b/tests/ui/parser/macro/macro-doc-comments-2.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `[`
+error: no rules expected `[`
   --> $DIR/macro-doc-comments-2.rs:6:5
    |
 LL | macro_rules! inner {
diff --git a/tests/ui/parser/macro/macro-expand-to-match-arm.rs b/tests/ui/parser/macro/macro-expand-to-match-arm.rs
index db38fa0d7bc65..0e27836b718bc 100644
--- a/tests/ui/parser/macro/macro-expand-to-match-arm.rs
+++ b/tests/ui/parser/macro/macro-expand-to-match-arm.rs
@@ -1,7 +1,7 @@
 macro_rules! arm {
     ($pattern:pat => $block:block) => {
         $pattern => $block
-        //~^ ERROR macro expansion ignores token `=>` and any following
+        //~^ ERROR macro expansion ignores `=>` and any tokens following
         //~| NOTE the usage of `arm!` is likely invalid in pattern context
         //~| NOTE macros cannot expand to match arms
     };
diff --git a/tests/ui/parser/macro/macro-expand-to-match-arm.stderr b/tests/ui/parser/macro/macro-expand-to-match-arm.stderr
index e3e7ff89c8134..1927d80fd724c 100644
--- a/tests/ui/parser/macro/macro-expand-to-match-arm.stderr
+++ b/tests/ui/parser/macro/macro-expand-to-match-arm.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `=>` and any following
+error: macro expansion ignores `=>` and any tokens following
   --> $DIR/macro-expand-to-match-arm.rs:3:18
    |
 LL |         $pattern => $block
diff --git a/tests/ui/parser/macro/macro-incomplete-parse.rs b/tests/ui/parser/macro/macro-incomplete-parse.rs
index 544e4aa7b1b09..612196aa4b276 100644
--- a/tests/ui/parser/macro/macro-incomplete-parse.rs
+++ b/tests/ui/parser/macro/macro-incomplete-parse.rs
@@ -2,7 +2,7 @@ macro_rules! ignored_item {
     () => {
         fn foo() {}
         fn bar() {}
-        , //~ ERROR macro expansion ignores token `,`
+        , //~ ERROR macro expansion ignores `,`
     }
 }
 
@@ -13,7 +13,7 @@ macro_rules! ignored_expr {
 }
 
 macro_rules! ignored_pat {
-    () => ( 1, 2 ) //~ ERROR macro expansion ignores token `,`
+    () => ( 1, 2 ) //~ ERROR macro expansion ignores `,`
 }
 
 ignored_item!();
diff --git a/tests/ui/parser/macro/macro-incomplete-parse.stderr b/tests/ui/parser/macro/macro-incomplete-parse.stderr
index 707417b725e9f..096b5f718ae1c 100644
--- a/tests/ui/parser/macro/macro-incomplete-parse.stderr
+++ b/tests/ui/parser/macro/macro-incomplete-parse.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `,` and any following
+error: macro expansion ignores `,` and any tokens following
   --> $DIR/macro-incomplete-parse.rs:5:9
    |
 LL |         ,
@@ -20,7 +20,7 @@ LL |     ignored_expr!();
    |
    = note: this error originates in the macro `ignored_expr` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: macro expansion ignores token `,` and any following
+error: macro expansion ignores `,` and any tokens following
   --> $DIR/macro-incomplete-parse.rs:16:14
    |
 LL |     () => ( 1, 2 )
diff --git a/tests/ui/parser/macro/trait-non-item-macros.rs b/tests/ui/parser/macro/trait-non-item-macros.rs
index 97fb564bf6479..e93000193b6e3 100644
--- a/tests/ui/parser/macro/trait-non-item-macros.rs
+++ b/tests/ui/parser/macro/trait-non-item-macros.rs
@@ -1,7 +1,7 @@
 macro_rules! bah {
     ($a:expr) => {
         $a
-    }; //~^ ERROR macro expansion ignores token `2` and any following
+    }; //~^ ERROR macro expansion ignores expression `2` and any tokens following
 }
 
 trait Bar {
diff --git a/tests/ui/parser/macro/trait-non-item-macros.stderr b/tests/ui/parser/macro/trait-non-item-macros.stderr
index db20e6b24aa03..1a82848377895 100644
--- a/tests/ui/parser/macro/trait-non-item-macros.stderr
+++ b/tests/ui/parser/macro/trait-non-item-macros.stderr
@@ -1,4 +1,4 @@
-error: macro expansion ignores token `2` and any following
+error: macro expansion ignores expression `2` and any tokens following
   --> $DIR/trait-non-item-macros.rs:3:9
    |
 LL |         $a
diff --git a/tests/ui/proc-macro/attr-invalid-exprs.rs b/tests/ui/proc-macro/attr-invalid-exprs.rs
index 3d8806ee80030..ec0b79469a457 100644
--- a/tests/ui/proc-macro/attr-invalid-exprs.rs
+++ b/tests/ui/proc-macro/attr-invalid-exprs.rs
@@ -13,7 +13,7 @@ fn main() {
     //~^ ERROR expected expression, found end of macro arguments
 
     let _ = #[duplicate] "Hello, world!";
-    //~^ ERROR macro expansion ignores token `,` and any following
+    //~^ ERROR macro expansion ignores `,` and any tokens following
 
     let _ = {
         #[no_output]
@@ -22,7 +22,7 @@ fn main() {
 
     let _ = {
         #[duplicate]
-        //~^ ERROR macro expansion ignores token `,` and any following
+        //~^ ERROR macro expansion ignores `,` and any tokens following
         "Hello, world!"
     };
 }
diff --git a/tests/ui/proc-macro/attr-invalid-exprs.stderr b/tests/ui/proc-macro/attr-invalid-exprs.stderr
index f96939bb6efce..0d500c871453f 100644
--- a/tests/ui/proc-macro/attr-invalid-exprs.stderr
+++ b/tests/ui/proc-macro/attr-invalid-exprs.stderr
@@ -4,7 +4,7 @@ error: expected expression, found end of macro arguments
 LL |     let _ = #[no_output] "Hello, world!";
    |             ^^^^^^^^^^^^
 
-error: macro expansion ignores token `,` and any following
+error: macro expansion ignores `,` and any tokens following
   --> $DIR/attr-invalid-exprs.rs:15:13
    |
 LL |     let _ = #[duplicate] "Hello, world!";
@@ -16,7 +16,7 @@ help: you might be missing a semicolon here
 LL |     let _ = #[duplicate]; "Hello, world!";
    |                         +
 
-error: macro expansion ignores token `,` and any following
+error: macro expansion ignores `,` and any tokens following
   --> $DIR/attr-invalid-exprs.rs:24:9
    |
 LL |         #[duplicate]
diff --git a/tests/ui/proc-macro/expand-expr.rs b/tests/ui/proc-macro/expand-expr.rs
index 5f7375d7450d6..e06ddc51a297e 100644
--- a/tests/ui/proc-macro/expand-expr.rs
+++ b/tests/ui/proc-macro/expand-expr.rs
@@ -114,8 +114,8 @@ expand_expr_fail!(echo_pm!($)); //~ ERROR: expected expression, found `$`
 
 // We get errors reported and recover during macro expansion if the macro
 // doesn't produce a valid expression.
-expand_expr_is!("string", echo_tts!("string"; hello)); //~ ERROR: macro expansion ignores token `hello` and any following
-expand_expr_is!("string", echo_pm!("string"; hello)); //~ ERROR: macro expansion ignores token `;` and any following
+expand_expr_is!("string", echo_tts!("string"; hello)); //~ ERROR: macro expansion ignores `hello` and any tokens following
+expand_expr_is!("string", echo_pm!("string"; hello)); //~ ERROR: macro expansion ignores `;` and any tokens following
 
 // For now, fail if a non-literal expression is expanded.
 expand_expr_fail!(arbitrary_expression() + "etc");
diff --git a/tests/ui/proc-macro/expand-expr.stderr b/tests/ui/proc-macro/expand-expr.stderr
index 2b92472e5ab75..8b1df177cfa6d 100644
--- a/tests/ui/proc-macro/expand-expr.stderr
+++ b/tests/ui/proc-macro/expand-expr.stderr
@@ -22,7 +22,7 @@ error: expected expression, found `$`
 LL | expand_expr_fail!(echo_pm!($));
    |                            ^ expected expression
 
-error: macro expansion ignores token `hello` and any following
+error: macro expansion ignores `hello` and any tokens following
   --> $DIR/expand-expr.rs:117:47
    |
 LL | expand_expr_is!("string", echo_tts!("string"; hello));
@@ -34,7 +34,7 @@ help: you might be missing a semicolon here
 LL | expand_expr_is!("string", echo_tts!("string"; hello););
    |                                                     +
 
-error: macro expansion ignores token `;` and any following
+error: macro expansion ignores `;` and any tokens following
   --> $DIR/expand-expr.rs:118:44
    |
 LL | expand_expr_is!("string", echo_pm!("string"; hello));
diff --git a/tests/ui/repr/repr-c-dead-variants.aarch64-unknown-linux-gnu.stderr b/tests/ui/repr/repr-c-dead-variants.aarch64-unknown-linux-gnu.stderr
index e2e57fe0e7311..64a0cb7f31a14 100644
--- a/tests/ui/repr/repr-c-dead-variants.aarch64-unknown-linux-gnu.stderr
+++ b/tests/ui/repr/repr-c-dead-variants.aarch64-unknown-linux-gnu.stderr
@@ -190,7 +190,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                abi: Align(8 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -254,7 +254,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                            abi: Align(8 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/repr/repr-c-dead-variants.armebv7r-none-eabi.stderr b/tests/ui/repr/repr-c-dead-variants.armebv7r-none-eabi.stderr
index 6ecdab1cc140c..5c4daa6d51977 100644
--- a/tests/ui/repr/repr-c-dead-variants.armebv7r-none-eabi.stderr
+++ b/tests/ui/repr/repr-c-dead-variants.armebv7r-none-eabi.stderr
@@ -190,7 +190,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                abi: Align(8 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -254,7 +254,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                            abi: Align(8 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/repr/repr-c-dead-variants.i686-pc-windows-msvc.stderr b/tests/ui/repr/repr-c-dead-variants.i686-pc-windows-msvc.stderr
index e2e57fe0e7311..64a0cb7f31a14 100644
--- a/tests/ui/repr/repr-c-dead-variants.i686-pc-windows-msvc.stderr
+++ b/tests/ui/repr/repr-c-dead-variants.i686-pc-windows-msvc.stderr
@@ -190,7 +190,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                abi: Align(8 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -254,7 +254,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                            abi: Align(8 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/repr/repr-c-dead-variants.x86_64-unknown-linux-gnu.stderr b/tests/ui/repr/repr-c-dead-variants.x86_64-unknown-linux-gnu.stderr
index e2e57fe0e7311..64a0cb7f31a14 100644
--- a/tests/ui/repr/repr-c-dead-variants.x86_64-unknown-linux-gnu.stderr
+++ b/tests/ui/repr/repr-c-dead-variants.x86_64-unknown-linux-gnu.stderr
@@ -190,7 +190,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                abi: Align(8 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -254,7 +254,7 @@ error: layout_of(DeadBranchHasOtherField) = Layout {
                            abi: Align(8 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/repr/repr-c-int-dead-variants.stderr b/tests/ui/repr/repr-c-int-dead-variants.stderr
index f7df576df248b..75005a64523a3 100644
--- a/tests/ui/repr/repr-c-int-dead-variants.stderr
+++ b/tests/ui/repr/repr-c-int-dead-variants.stderr
@@ -190,7 +190,7 @@ error: layout_of(DeadBranchHasOtherFieldU8) = Layout {
                abi: Align(8 bytes),
                pref: $SOME_ALIGN,
            },
-           abi: Aggregate {
+           abi: Memory {
                sized: true,
            },
            fields: Arbitrary {
@@ -254,7 +254,7 @@ error: layout_of(DeadBranchHasOtherFieldU8) = Layout {
                            abi: Align(8 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs
index b8c0eb3e6d6d7..4b2fc4a03b620 100644
--- a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs
+++ b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs
@@ -68,7 +68,7 @@ fn _macros() {
         _ => {}
     }
     use_expr!(let 0 = 1);
-    //~^ ERROR no rules expected the token `let`
+    //~^ ERROR no rules expected keyword `let`
 }
 
 fn main() {}
diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr
index 2341dbbbdbd00..1c710b04897cb 100644
--- a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr
+++ b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr
@@ -131,7 +131,7 @@ LL |     use_expr!((let 0 = 1));
    |
    = note: only supported directly in conditions of `if` and `while` expressions
 
-error: no rules expected the token `let`
+error: no rules expected keyword `let`
   --> $DIR/feature-gate.rs:70:15
    |
 LL |     macro_rules! use_expr {
diff --git a/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.rs b/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.rs
index bca7564efd83f..2087fc42cf102 100644
--- a/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.rs
+++ b/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.rs
@@ -54,7 +54,7 @@ fn _macros() {
     #[cfg(FALSE)] (let 0 = 1);
     //~^ ERROR expected expression, found `let` statement
     use_expr!(let 0 = 1);
-    //~^ ERROR no rules expected the token `let`
+    //~^ ERROR no rules expected keyword `let`
 }
 
 fn main() {}
diff --git a/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.stderr b/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.stderr
index 2b1a49be3daa5..7c874ae78a8ad 100644
--- a/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.stderr
+++ b/tests/ui/rfcs/rfc-2497-if-let-chains/feature-gate.stderr
@@ -14,7 +14,7 @@ LL |     noop_expr!((let 0 = 1));
    |
    = note: only supported directly in conditions of `if` and `while` expressions
 
-error: no rules expected the token `let`
+error: no rules expected keyword `let`
   --> $DIR/feature-gate.rs:56:15
    |
 LL |     macro_rules! use_expr {
diff --git a/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.disallowed.stderr b/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.disallowed.stderr
index be4a523155825..130d0296c5ece 100644
--- a/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.disallowed.stderr
+++ b/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.disallowed.stderr
@@ -111,5 +111,23 @@ LL |     while let Some(ref first) = opt && let second = first && let _third = s
    = note: these patterns will always match
    = help: consider moving them into the body
 
-error: aborting due to 12 previous errors
+error: trailing irrefutable pattern in let chain
+  --> $DIR/irrefutable-lets.rs:87:12
+   |
+LL |         && let x = &opt
+   |            ^^^^^^^^^^^^
+   |
+   = note: this pattern will always match
+   = help: consider moving it into the body
+
+error: leading irrefutable pattern in let chain
+  --> $DIR/irrefutable-lets.rs:93:12
+   |
+LL |         if let x = opt.clone().map(|_| 1)
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this pattern will always match
+   = help: consider moving it outside of the construct
+
+error: aborting due to 14 previous errors
 
diff --git a/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.rs b/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.rs
index bd4df337614a0..e7d69f89773ee 100644
--- a/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.rs
+++ b/tests/ui/rfcs/rfc-2497-if-let-chains/irrefutable-lets.rs
@@ -75,4 +75,24 @@ fn main() {
         && let Range { start: local_start, end: _ } = first
         && let None = local_start {
     }
+
+    // No error. An extra nesting level would be required for the `else if`.
+    if opt == Some(None..None) {
+    } else if let x = opt.clone().map(|_| 1)
+        && x == Some(1)
+    {}
+
+    if opt == Some(None..None) {
+    } else if opt.is_some()
+        && let x = &opt
+        //[disallowed]~^ ERROR trailing irrefutable pattern in let chain
+    {}
+
+    if opt == Some(None..None) {
+    } else {
+        if let x = opt.clone().map(|_| 1)
+        //[disallowed]~^ ERROR leading irrefutable pattern in let chain
+            && x == Some(1)
+        {}
+    }
 }
diff --git a/tests/ui/type/pattern_types/range_patterns.stderr b/tests/ui/type/pattern_types/range_patterns.stderr
index 8465e1b7ff275..7bd0d826cab71 100644
--- a/tests/ui/type/pattern_types/range_patterns.stderr
+++ b/tests/ui/type/pattern_types/range_patterns.stderr
@@ -124,7 +124,7 @@ error: layout_of(Option<(u32) is 1..=>) = Layout {
                            abi: Align(1 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
@@ -232,7 +232,7 @@ error: layout_of(Option<NonZero<u32>>) = Layout {
                            abi: Align(1 bytes),
                            pref: $SOME_ALIGN,
                        },
-                       abi: Aggregate {
+                       abi: Memory {
                            sized: true,
                        },
                        fields: Arbitrary {
diff --git a/tests/ui/underscore-ident-matcher.rs b/tests/ui/underscore-ident-matcher.rs
index bddc8c80a7b96..77ec70d43d54e 100644
--- a/tests/ui/underscore-ident-matcher.rs
+++ b/tests/ui/underscore-ident-matcher.rs
@@ -5,5 +5,5 @@ macro_rules! identity {
 }
 
 fn main() {
-    let identity!(_) = 10; //~ ERROR no rules expected the token `_`
+    let identity!(_) = 10; //~ ERROR no rules expected reserved identifier `_`
 }
diff --git a/tests/ui/underscore-ident-matcher.stderr b/tests/ui/underscore-ident-matcher.stderr
index a663f34cde1b1..0c3f980cf6c71 100644
--- a/tests/ui/underscore-ident-matcher.stderr
+++ b/tests/ui/underscore-ident-matcher.stderr
@@ -1,4 +1,4 @@
-error: no rules expected the token `_`
+error: no rules expected reserved identifier `_`
   --> $DIR/underscore-ident-matcher.rs:8:19
    |
 LL | macro_rules! identity {