Merge pull request #1025 from comex/blr-optimization

Opportunistically predict BLR destinations using RET.

Source/Core/Common/MemoryUtil.cpp

@@ -158,6 +158,25 @@ void FreeAlignedMemory(void* ptr)
 	}
 }
 
+void ReadProtectMemory(void* ptr, size_t size)
+{
+	bool error_occurred = false;
+
+#ifdef _WIN32
+	DWORD oldValue;
+	if (!VirtualProtect(ptr, size, PAGE_NOACCESS, &oldValue))
+		error_occurred = true;
+#else
+	int retval = mprotect(ptr, size, PROT_NONE);
+
+	if (retval != 0)
+		error_occurred = true;
+#endif
+
+	if (error_occurred)
+		PanicAlert("ReadProtectMemory failed!\n%s", GetLastErrorMsg());
+}
+
 void WriteProtectMemory(void* ptr, size_t size, bool allowExecute)
 {
 	bool error_occurred = false;

Source/Core/Common/MemoryUtil.h

@@ -12,8 +12,12 @@ void* AllocateMemoryPages(size_t size);
 void FreeMemoryPages(void* ptr, size_t size);
 void* AllocateAlignedMemory(size_t size,size_t alignment);
 void FreeAlignedMemory(void* ptr);
+void ReadProtectMemory(void* ptr, size_t size);
 void WriteProtectMemory(void* ptr, size_t size, bool executable = false);
 void UnWriteProtectMemory(void* ptr, size_t size, bool allowExecute = false);
 std::string MemUsage();
 
+void GuardMemoryMake(void* ptr, size_t size);
+void GuardMemoryUnmake(void* ptr, size_t size);
+
 inline int GetPageSize() { return 4096; }

Source/Core/Common/x64Emitter.cpp

@@ -1766,6 +1766,8 @@ void XEmitter::ANDN(int bits, X64Reg regOp1, X64Reg regOp2, OpArg arg) {WriteBMI
 void XEmitter::LOCK()  { Write8(0xF0); }
 void XEmitter::REP()   { Write8(0xF3); }
 void XEmitter::REPNE() { Write8(0xF2); }
+void XEmitter::FSOverride() { Write8(0x64); }
+void XEmitter::GSOverride() { Write8(0x65); }
 
 void XEmitter::FWAIT()
 {

Source/Core/Common/x64Emitter.h

@@ -467,6 +467,8 @@ class XEmitter
 	void LOCK();
 	void REP();
 	void REPNE();
+	void FSOverride();
+	void GSOverride();
 
 	// x87
 	enum x87StatusWordBits {

Source/Core/Core/ArmMemTools.cpp

@@ -32,9 +32,9 @@ typedef struct ucontext {
 } ucontext_t;
 #endif
 
-void sigsegv_handler(int signal, siginfo_t *info, void *raw_context)
+static void sigsegv_handler(int sig, siginfo_t *info, void *raw_context)
 {
-	if (signal != SIGSEGV)
+	if (sig != SIGSEGV)
 	{
 		// We are not interested in other signals - handle it as usual.
 		return;
@@ -47,33 +47,18 @@ void sigsegv_handler(int signal, siginfo_t *info, void *raw_context)
 		return;
 	}
 
-
 	// Get all the information we can out of the context.
 	mcontext_t *ctx = &context->uc_mcontext;
 
-	void *fault_memory_ptr = (void*)ctx->arm_r10;
-	u8 *fault_instruction_ptr = (u8 *)ctx->arm_pc;
-
-	if (!JitInterface::IsInCodeSpace(fault_instruction_ptr))
-	{
-		// Let's not prevent debugging.
-		return;
-	}
+	// comex says hello, and is most curious whether this is arm_r10 for a
+	// reason as opposed to si_addr like the x64MemTools.cpp version.  Is there
+	// even a need for this file to be architecture specific?
+	uintptr_t fault_memory_ptr = (uintptr_t)ctx->arm_r10;
 
-	u64 bad_address = (u64)fault_memory_ptr;
-	u64 memspace_bottom = (u64)Memory::base;
-	if (bad_address < memspace_bottom)
+	if (!JitInterface::HandleFault(fault_memory_ptr, ctx))
 	{
-		PanicAlertT("Exception handler - access below memory space. %08llx%08llx",
-			bad_address >> 32, bad_address);
-	}
-
-	u32 em_address = (u32)(bad_address - memspace_bottom);
-
-	const u8 *new_rip = jit->BackPatch(fault_instruction_ptr, em_address, ctx);
-	if (new_rip)
-	{
-		ctx->arm_pc = (u32) new_rip;
+		// retry and crash
+		signal(SIGSEGV, SIG_DFL);
 	}
 }
 
@@ -86,4 +71,7 @@ void InstallExceptionHandler()
 	sigemptyset(&sa.sa_mask);
 	sigaction(SIGSEGV, &sa, nullptr);
 }
+
+void UninstallExceptionHandler() {}
+
 }  // namespace

Source/Core/Core/CMakeLists.txt

@@ -195,9 +195,10 @@ if(_M_X86)
 			PowerPC/Jit64/Jit_Paired.cpp
 			PowerPC/Jit64/JitRegCache.cpp
 			PowerPC/Jit64/Jit_SystemRegisters.cpp
-			PowerPC/JitCommon/JitBackpatch.cpp
 			PowerPC/JitCommon/JitAsmCommon.cpp
-			PowerPC/JitCommon/Jit_Util.cpp)
+			PowerPC/JitCommon/JitBackpatch.cpp
+			PowerPC/JitCommon/Jit_Util.cpp
+			PowerPC/JitCommon/TrampolineCache.cpp)
 elseif(_M_ARM_32)
 	set(SRCS ${SRCS}
 			ArmMemTools.cpp

Source/Core/Core/Core.cpp

@@ -277,6 +277,10 @@ static void CpuThread()
 	if (!_CoreParameter.bCPUThread)
 		g_video_backend->Video_Cleanup();
 
+	#if _M_X86_64 || _M_ARM_32
+	EMM::UninstallExceptionHandler();
+	#endif
+
 	return;
 }
 

Source/Core/Core/Core.vcxproj

@@ -229,6 +229,7 @@
     <ClCompile Include="PowerPC\JitCommon\JitBase.cpp" />
     <ClCompile Include="PowerPC\JitCommon\JitCache.cpp" />
     <ClCompile Include="PowerPC\JitCommon\Jit_Util.cpp" />
+    <ClCompile Include="PowerPC\JitCommon\TrampolineCache.cpp" />
     <ClCompile Include="PowerPC\JitInterface.cpp" />
     <ClCompile Include="PowerPC\PowerPC.cpp" />
     <ClCompile Include="PowerPC\PPCAnalyst.cpp" />
@@ -406,6 +407,7 @@
     <ClInclude Include="PowerPC\JitCommon\JitBase.h" />
     <ClInclude Include="PowerPC\JitCommon\JitCache.h" />
     <ClInclude Include="PowerPC\JitCommon\Jit_Util.h" />
+    <ClInclude Include="PowerPC\JitCommon\TrampolineCache.h" />
     <ClInclude Include="PowerPC\JitInterface.h" />
     <ClInclude Include="PowerPC\PowerPC.h" />
     <ClInclude Include="PowerPC\PPCAnalyst.h" />
@@ -464,4 +466,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
+</Project>

Source/Core/Core/Core.vcxproj.filters

@@ -640,6 +640,9 @@
     <ClCompile Include="PowerPC\JitCommon\JitCache.cpp">
       <Filter>PowerPC\JitCommon</Filter>
     </ClCompile>
+    <ClCompile Include="PowerPC\JitCommon\TrampolineCache.cpp">
+      <Filter>PowerPC\JitCommon</Filter>
+    </ClCompile>
     <ClCompile Include="PowerPC\Jit64IL\IR_X86.cpp">
       <Filter>PowerPC\JitIL</Filter>
     </ClCompile>
@@ -1182,6 +1185,9 @@
     <ClInclude Include="PowerPC\JitCommon\JitCache.h">
       <Filter>PowerPC\JitCommon</Filter>
     </ClInclude>
+    <ClInclude Include="PowerPC\JitCommon\TrampolineCache.h">
+      <Filter>PowerPC\JitCommon</Filter>
+    </ClInclude>
     <ClInclude Include="PowerPC\Jit64IL\JitIL.h">
       <Filter>PowerPC\JitIL</Filter>
     </ClInclude>
@@ -1204,4 +1210,4 @@
   <ItemGroup>
     <Text Include="CMakeLists.txt" />
   </ItemGroup>
-</Project>
+</Project>

Source/Core/Core/MemTools.h

@@ -11,4 +11,5 @@ namespace EMM
 {
 	typedef u32 EAddr;
 	void InstallExceptionHandler();
+	void UninstallExceptionHandler();
 }