From 49ae3b7867a09fefee26f1ff34890f7a3e230f28 Mon Sep 17 00:00:00 2001 From: bjorn3 <17426603+bjorn3@users.noreply.github.com> Date: Sat, 15 Jul 2023 12:38:59 +0000 Subject: [PATCH] Extract a create_wrapper_function for use in allocator shim writing This deduplicates some logic and makes it easier to follow what wrappers are produced. In the future it may allow moving the code to determine which wrappers to create to cg_ssa. --- compiler/rustc_codegen_llvm/src/allocator.rs | 182 +++++++++---------- 1 file changed, 90 insertions(+), 92 deletions(-) diff --git a/compiler/rustc_codegen_llvm/src/allocator.rs b/compiler/rustc_codegen_llvm/src/allocator.rs index ca123334fca3..48d4a9cf8036 100644 --- a/compiler/rustc_codegen_llvm/src/allocator.rs +++ b/compiler/rustc_codegen_llvm/src/allocator.rs @@ -9,7 +9,7 @@ use rustc_middle::ty::TyCtxt; use rustc_session::config::{DebugInfo, OomStrategy}; use crate::debuginfo; -use crate::llvm::{self, False, True}; +use crate::llvm::{self, Context, False, Module, True, Type}; use crate::ModuleLlvm; pub(crate) unsafe fn codegen( @@ -29,7 +29,6 @@ pub(crate) unsafe fn codegen( }; let i8 = llvm::LLVMInt8TypeInContext(llcx); let i8p = llvm::LLVMPointerTypeInContext(llcx, 0); - let void = llvm::LLVMVoidTypeInContext(llcx); if kind == AllocatorKind::Default { for method in ALLOCATOR_METHODS { @@ -54,102 +53,25 @@ pub(crate) unsafe fn codegen( panic!("invalid allocator output") } }; - let ty = llvm::LLVMFunctionType( - output.unwrap_or(void), - args.as_ptr(), - args.len() as c_uint, - False, - ); - let name = global_fn_name(method.name); - let llfn = - llvm::LLVMRustGetOrInsertFunction(llmod, name.as_ptr().cast(), name.len(), ty); - - if tcx.sess.target.default_hidden_visibility { - llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden); - } - if tcx.sess.must_emit_unwind_tables() { - let uwtable = attributes::uwtable_attr(llcx); - attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[uwtable]); - } - let callee = default_fn_name(method.name); - let callee = - llvm::LLVMRustGetOrInsertFunction(llmod, callee.as_ptr().cast(), callee.len(), ty); - llvm::LLVMRustSetVisibility(callee, llvm::Visibility::Hidden); - - let llbb = llvm::LLVMAppendBasicBlockInContext(llcx, llfn, "entry\0".as_ptr().cast()); - - let llbuilder = llvm::LLVMCreateBuilderInContext(llcx); - llvm::LLVMPositionBuilderAtEnd(llbuilder, llbb); - let args = args - .iter() - .enumerate() - .map(|(i, _)| llvm::LLVMGetParam(llfn, i as c_uint)) - .collect::>(); - let ret = llvm::LLVMRustBuildCall( - llbuilder, - ty, - callee, - args.as_ptr(), - args.len() as c_uint, - [].as_ptr(), - 0 as c_uint, - ); - llvm::LLVMSetTailCall(ret, True); - if output.is_some() { - llvm::LLVMBuildRet(llbuilder, ret); - } else { - llvm::LLVMBuildRetVoid(llbuilder); - } - llvm::LLVMDisposeBuilder(llbuilder); + let from_name = global_fn_name(method.name); + let to_name = default_fn_name(method.name); + + create_wrapper_function(tcx, llcx, llmod, &from_name, &to_name, &args, output, false); } } // rust alloc error handler - let args = [usize, usize]; // size, align - - let ty = llvm::LLVMFunctionType(void, args.as_ptr(), args.len() as c_uint, False); - let name = "__rust_alloc_error_handler"; - let llfn = llvm::LLVMRustGetOrInsertFunction(llmod, name.as_ptr().cast(), name.len(), ty); - // -> ! DIFlagNoReturn - let no_return = llvm::AttributeKind::NoReturn.create_attr(llcx); - attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[no_return]); - - if tcx.sess.target.default_hidden_visibility { - llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden); - } - if tcx.sess.must_emit_unwind_tables() { - let uwtable = attributes::uwtable_attr(llcx); - attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[uwtable]); - } - - let callee = alloc_error_handler_name(alloc_error_handler_kind); - let callee = llvm::LLVMRustGetOrInsertFunction(llmod, callee.as_ptr().cast(), callee.len(), ty); - // -> ! DIFlagNoReturn - attributes::apply_to_llfn(callee, llvm::AttributePlace::Function, &[no_return]); - llvm::LLVMRustSetVisibility(callee, llvm::Visibility::Hidden); - - let llbb = llvm::LLVMAppendBasicBlockInContext(llcx, llfn, "entry\0".as_ptr().cast()); - - let llbuilder = llvm::LLVMCreateBuilderInContext(llcx); - llvm::LLVMPositionBuilderAtEnd(llbuilder, llbb); - let args = args - .iter() - .enumerate() - .map(|(i, _)| llvm::LLVMGetParam(llfn, i as c_uint)) - .collect::>(); - let ret = llvm::LLVMRustBuildCall( - llbuilder, - ty, - callee, - args.as_ptr(), - args.len() as c_uint, - [].as_ptr(), - 0 as c_uint, + create_wrapper_function( + tcx, + llcx, + llmod, + "__rust_alloc_error_handler", + &alloc_error_handler_name(alloc_error_handler_kind), + &[usize, usize], // size, align + None, + true, ); - llvm::LLVMSetTailCall(ret, True); - llvm::LLVMBuildRetVoid(llbuilder); - llvm::LLVMDisposeBuilder(llbuilder); // __rust_alloc_error_handler_should_panic let name = OomStrategy::SYMBOL; @@ -175,3 +97,79 @@ pub(crate) unsafe fn codegen( dbg_cx.finalize(tcx.sess); } } + +fn create_wrapper_function( + tcx: TyCtxt<'_>, + llcx: &Context, + llmod: &Module, + from_name: &str, + to_name: &str, + args: &[&Type], + output: Option<&Type>, + no_return: bool, +) { + unsafe { + let ty = llvm::LLVMFunctionType( + output.unwrap_or_else(|| llvm::LLVMVoidTypeInContext(llcx)), + args.as_ptr(), + args.len() as c_uint, + False, + ); + let llfn = llvm::LLVMRustGetOrInsertFunction( + llmod, + from_name.as_ptr().cast(), + from_name.len(), + ty, + ); + let no_return = if no_return { + // -> ! DIFlagNoReturn + let no_return = llvm::AttributeKind::NoReturn.create_attr(llcx); + attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[no_return]); + Some(no_return) + } else { + None + }; + + if tcx.sess.target.default_hidden_visibility { + llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden); + } + if tcx.sess.must_emit_unwind_tables() { + let uwtable = attributes::uwtable_attr(llcx); + attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[uwtable]); + } + + let callee = + llvm::LLVMRustGetOrInsertFunction(llmod, to_name.as_ptr().cast(), to_name.len(), ty); + if let Some(no_return) = no_return { + // -> ! DIFlagNoReturn + attributes::apply_to_llfn(callee, llvm::AttributePlace::Function, &[no_return]); + } + llvm::LLVMRustSetVisibility(callee, llvm::Visibility::Hidden); + + let llbb = llvm::LLVMAppendBasicBlockInContext(llcx, llfn, "entry\0".as_ptr().cast()); + + let llbuilder = llvm::LLVMCreateBuilderInContext(llcx); + llvm::LLVMPositionBuilderAtEnd(llbuilder, llbb); + let args = args + .iter() + .enumerate() + .map(|(i, _)| llvm::LLVMGetParam(llfn, i as c_uint)) + .collect::>(); + let ret = llvm::LLVMRustBuildCall( + llbuilder, + ty, + callee, + args.as_ptr(), + args.len() as c_uint, + [].as_ptr(), + 0 as c_uint, + ); + llvm::LLVMSetTailCall(ret, True); + if output.is_some() { + llvm::LLVMBuildRet(llbuilder, ret); + } else { + llvm::LLVMBuildRetVoid(llbuilder); + } + llvm::LLVMDisposeBuilder(llbuilder); + } +}