From c8bb3cc50e32e957609ee190dd5f35b9a349f640 Mon Sep 17 00:00:00 2001
From: gdkchan <gab.dark.100@gmail.com>
Date: Sun, 13 Dec 2020 12:19:38 -0300
Subject: [PATCH] Fix register read after write on STREX implementation (#1801)
* Fix register read after write on STREX implementation
* PTC version update
---
.../Instructions/InstEmitMemoryExHelper.cs | 19 ++++++++++++++++++-
ARMeilleure/Translation/PTC/Ptc.cs | 2 +-
2 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/ARMeilleure/Instructions/InstEmitMemoryExHelper.cs b/ARMeilleure/Instructions/InstEmitMemoryExHelper.cs
index 5b890dd395..317e4276ee 100644
--- a/ARMeilleure/Instructions/InstEmitMemoryExHelper.cs
+++ b/ARMeilleure/Instructions/InstEmitMemoryExHelper.cs
@@ -48,6 +48,18 @@ namespace ARMeilleure.Instructions
Operand exValuePtr = context.Add(arg0, Const((long)NativeContext.GetExclusiveValueOffset()));
context.Store(exAddrPtr, context.BitwiseAnd(address, Const(address.Type, GetExclusiveAddressMask())));
+
+ // Make sure the unused higher bits of the value are cleared.
+ if (size < 3)
+ {
+ context.Store(exValuePtr, Const(0UL));
+ }
+ if (size < 4)
+ {
+ context.Store(context.Add(exValuePtr, Const(exValuePtr.Type, 8L)), Const(0UL));
+ }
+
+ // Store the new exclusive value.
context.Store(exValuePtr, value);
return value;
@@ -74,6 +86,11 @@ namespace ARMeilleure.Instructions
if (exclusive)
{
+ // We overwrite one of the register (Rs),
+ // keep a copy of the values to ensure we are working with the correct values.
+ address = context.Copy(address);
+ value = context.Copy(value);
+
void SetRs(Operand value)
{
if (a32)
@@ -98,7 +115,7 @@ namespace ARMeilleure.Instructions
Operand lblExit = Label();
- SetRs(exFailed);
+ SetRs(Const(1));
context.BranchIfTrue(lblExit, exFailed);
diff --git a/ARMeilleure/Translation/PTC/Ptc.cs b/ARMeilleure/Translation/PTC/Ptc.cs
index 2145f350ff..05dd352ebf 100644
--- a/ARMeilleure/Translation/PTC/Ptc.cs
+++ b/ARMeilleure/Translation/PTC/Ptc.cs
@@ -21,7 +21,7 @@ namespace ARMeilleure.Translation.PTC
{
private const string HeaderMagic = "PTChd";
- private const int InternalVersion = 1783; //! To be incremented manually for each change to the ARMeilleure project.
+ private const int InternalVersion = 1801; //! To be incremented manually for each change to the ARMeilleure project.
private const string ActualDir = "0";
private const string BackupDir = "1";