Clear F3/F2 bits

icedland · Mar 19, 2021 · 8c88ee3 · 8c88ee3
1 parent 660927c
commit 8c88ee3
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Showing 5 changed files with 16 additions and 18 deletions.
diff --git a/src/csharp/Intel/Iced/Intel/Decoder.cs b/src/csharp/Intel/Iced/Intel/Decoder.cs
@@ -454,16 +454,10 @@ public void Decode(out Instruction instruction) {
 		[MethodImpl(MethodImplOptions.AggressiveInlining)]
 		internal ulong GetCurrentInstructionPointer64() => instructionPointer + state.instructionLength;
 
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
 		internal void ClearMandatoryPrefix(ref Instruction instruction) {
 			Debug.Assert(state.Encoding == EncodingKind.Legacy);
-			switch (state.mandatoryPrefix) {
-			case MandatoryPrefixByte.PF3:
-				instruction.InternalClearHasRepePrefix();
-				break;
-			case MandatoryPrefixByte.PF2:
-				instruction.InternalClearHasRepnePrefix();
-				break;
-			}
+			instruction.InternalClearHasRepeRepnePrefix();
 		}
 
 		[MethodImpl(MethodImplOptions.AggressiveInlining)]

diff --git a/src/csharp/Intel/Iced/Intel/Instruction.cs b/src/csharp/Intel/Iced/Intel/Instruction.cs
@@ -380,6 +380,8 @@ public bool HasRepePrefix {
 		internal void InternalSetHasRepePrefix() => codeFlags = (codeFlags & ~(uint)CodeFlags.RepnePrefix) | (uint)CodeFlags.RepePrefix;
 		[MethodImpl(MethodImplOptions.AggressiveInlining)]
 		internal void InternalClearHasRepePrefix() => codeFlags &= ~(uint)CodeFlags.RepePrefix;
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		internal void InternalClearHasRepeRepnePrefix() => codeFlags &= ~((uint)CodeFlags.RepePrefix | (uint)CodeFlags.RepnePrefix);
 
 		/// <summary>
 		/// <see langword="true"/> if the instruction has the <c>REPNE</c> prefix (<c>F2</c>)

diff --git a/src/rust/iced-x86/src/decoder.rs b/src/rust/iced-x86/src/decoder.rs
@@ -1345,16 +1345,10 @@ impl<'a> Decoder<'a> {
 		((self.data_ptr - self.instr_start_data_ptr) as u64).wrapping_add(self.ip)
 	}
 
-	// It's not possible to use 'as u32' on the left side in a match arm
-	const PF3: u32 = MandatoryPrefixByte::PF3 as u32;
-	const PF2: u32 = MandatoryPrefixByte::PF2 as u32;
+	#[inline]
 	fn clear_mandatory_prefix(&mut self, instruction: &mut Instruction) {
 		debug_assert_eq!(self.state.encoding(), EncodingKind::Legacy);
-		match self.state.mandatory_prefix {
-			Decoder::PF3 => instruction_internal::internal_clear_has_repe_prefix(instruction),
-			Decoder::PF2 => instruction_internal::internal_clear_has_repne_prefix(instruction),
-			_ => {}
-		}
+		instruction_internal::internal_clear_has_repe_repne_prefix(instruction);
 	}
 
 	#[inline(always)]
@@ -1364,6 +1358,8 @@ impl<'a> Decoder<'a> {
 		}
 	}
 
+	const PF3: u32 = MandatoryPrefixByte::PF3 as u32;
+	const PF2: u32 = MandatoryPrefixByte::PF2 as u32;
 	fn set_xacquire_xrelease_core(&mut self, instruction: &mut Instruction, flags: u32) {
 		debug_assert!(!((flags & HandlerFlags::XACQUIRE_XRELEASE_NO_LOCK) == 0 && !instruction.has_lock_prefix()));
 		match self.state.mandatory_prefix {

diff --git a/src/rust/iced-x86/src/decoder/handlers_legacy.rs b/src/rust/iced-x86/src/decoder/handlers_legacy.rs
@@ -441,13 +441,13 @@ impl OpCodeHandler_MandatoryPrefix4 {
 				}
 				this.handler_f3
 			}
-			3 => {
+			_ => {
+				debug_assert_eq!(decoder.state.mandatory_prefix, 3);
 				if (this.flags & 8) != 0 {
 					decoder.clear_mandatory_prefix_f2(instruction);
 				}
 				this.handler_f2
 			}
-			_ => unreachable!(),
 		};
 		if handler.has_modrm && (this.flags & 0x10) != 0 {
 			decoder.read_modrm();

diff --git a/src/rust/iced-x86/src/instruction_internal.rs b/src/rust/iced-x86/src/instruction_internal.rs
@@ -92,6 +92,12 @@ pub(crate) fn internal_has_op_mask_or_zeroing_masking(this: &Instruction) -> boo
 	(this.code_flags & ((CodeFlags::OP_MASK_MASK << CodeFlags::OP_MASK_SHIFT) | CodeFlags::ZEROING_MASKING)) != 0
 }
 
+#[cfg(feature = "decoder")]
+#[inline]
+pub(crate) fn internal_clear_has_repe_repne_prefix(this: &mut Instruction) {
+	this.code_flags &= !(CodeFlags::REPE_PREFIX | CodeFlags::REPNE_PREFIX)
+}
+
 #[cfg(feature = "decoder")]
 #[inline]
 pub(crate) fn internal_clear_has_repe_prefix(this: &mut Instruction) {