From c553c42d63daad7aafbd2996da1f05ce2a911635 Mon Sep 17 00:00:00 2001
From: Pierre Bourdon <delroth@gmail.com>
Date: Sat, 19 Jan 2013 05:09:00 +0100
Subject: [PATCH] Implement backpatch support for 16 bit loads

---
 Source/Core/Core/Src/PowerPC/JitCommon/JitBackpatch.cpp | 7 +++++--
 Source/Core/Core/Src/PowerPC/JitCommon/Jit_Util.cpp     | 7 ++++---
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/Source/Core/Core/Src/PowerPC/JitCommon/JitBackpatch.cpp b/Source/Core/Core/Src/PowerPC/JitCommon/JitBackpatch.cpp
index 9337f87b77..e2d9b50d42 100644
--- a/Source/Core/Core/Src/PowerPC/JitCommon/JitBackpatch.cpp
+++ b/Source/Core/Core/Src/PowerPC/JitCommon/JitBackpatch.cpp
@@ -90,6 +90,10 @@ const u8 *TrampolineCache::GetReadTrampoline(const InstructionInfo &info)
 	case 4:
 		CALL(thunks.ProtectFunction((void *)&Memory::Read_U32, 1));
 		break;
+	case 2:
+		CALL(thunks.ProtectFunction((void *)&Memory::Read_U16, 1));
+		SHL(32, R(EAX), Imm8(16));
+		break;
 	}
 	ABI_PopAllCallerSavedRegsAndAdjustStack();
 	if (dataReg != EAX) {
@@ -176,7 +180,7 @@ const u8 *JitBase::BackPatch(u8 *codePtr, int accessType, u32 emAddress, void *c
 					   codePtr, emAddress);
 	}*/
 
-	if (info.operandSize != 4) {
+	if (info.operandSize == 1) {
 		BackPatchError(StringFromFormat("BackPatch - no support for operand size %i", info.operandSize), codePtr, emAddress);
 	}
 
@@ -188,7 +192,6 @@ const u8 *JitBase::BackPatch(u8 *codePtr, int accessType, u32 emAddress, void *c
 		PanicAlert("BackPatch : Currently only supporting reads."
 		           "\n\nAttempted to write to %08x.", emAddress);
 
-	// In the first iteration, we assume that all accesses are 32-bit. We also only deal with reads.
 	if (accessType == 0)
 	{
 		XEmitter emitter(codePtr);
diff --git a/Source/Core/Core/Src/PowerPC/JitCommon/Jit_Util.cpp b/Source/Core/Core/Src/PowerPC/JitCommon/Jit_Util.cpp
index 4cfc3ab934..f43604fa9b 100644
--- a/Source/Core/Core/Src/PowerPC/JitCommon/Jit_Util.cpp
+++ b/Source/Core/Core/Src/PowerPC/JitCommon/Jit_Util.cpp
@@ -120,12 +120,13 @@ void EmuCodeBlock::SafeLoadToEAX(const Gen::OpArg & opAddress, int accessSize, s
 {
 #if defined(_M_X64)
 #ifdef ENABLE_MEM_CHECK
-	if (accessSize == 32 && !Core::g_CoreStartupParameter.bMMU && !Core::g_CoreStartupParameter.bEnableDebugging)
+	if (accessSize != 8 && !Core::g_CoreStartupParameter.bMMU && !Core::g_CoreStartupParameter.bEnableDebugging)
 #else
-	if (accessSize == 32 && !Core::g_CoreStartupParameter.bMMU)
+	if (accessSize != 8 && !Core::g_CoreStartupParameter.bMMU)
 #endif
 	{
-		// BackPatch only supports 32-bits accesses
+		// We don't support 8 bit loads backpatching at the moment, but they
+		// are very rare.
 		UnsafeLoadToEAX(opAddress, accessSize, offset, signExtend);
 	}
 	else