Don't erase and rewrite the dispatcher when the cache is cleared. Fixes #9708

Common/Arm64Emitter.cpp

@@ -302,7 +302,7 @@ const u8* ARM64XEmitter::AlignCode16()
 {
 	int c = int((u64)m_code & 15);
 	if (c)
-		ReserveCodeSpace(16-c);
+		ReserveCodeSpace(16 - c);
 	return m_code;
 }
 
@@ -509,7 +509,7 @@ void ARM64XEmitter::EncodeTestBranchInst(u32 op, ARM64Reg Rt, u8 bits, const voi
 
 	distance >>= 2;
 
-	_assert_msg_(DYNA_REC, distance >= -0x3FFF && distance < 0x3FFF, "%s: Received too large distance: %llx", __FUNCTION__, distance);
+	_assert_msg_(DYNA_REC, distance >= -0x1FFF && distance < 0x1FFF, "%s: Received too large distance: %llx", __FUNCTION__, distance);
 
 	Rt = DecodeReg(Rt);
 	Write32((b64Bit << 31) | (0x36 << 24) | (op << 24) | \
@@ -3896,4 +3896,15 @@ void ARM64XEmitter::SUBSI2R(ARM64Reg Rd, ARM64Reg Rn, u64 imm, ARM64Reg scratch)
 	}
 }
 
+void ARM64CodeBlock::PoisonMemory(int offset) {
+	u32* ptr = (u32*)(region + offset);
+	u32* maxptr = (u32*)(region + region_size - offset);
+	// If our memory isn't a multiple of u32 then this won't write the last remaining bytes with anything
+	// Less than optimal, but there would be nothing we could do but throw a runtime warning anyway.
+	// AArch64: 0xD4200000 = BRK 0
+	while (ptr < maxptr)
+		*ptr++ = 0xD4200000;
+	FlushIcacheSection((u8 *)ptr, (u8 *)maxptr);
+}
+
 }  // namespace

Common/Arm64Emitter.h

@@ -985,15 +985,6 @@ private:
 class ARM64CodeBlock : public CodeBlock<ARM64XEmitter>
 {
 private:
-	void PoisonMemory() override
-	{
-		u32* ptr = (u32*)region;
-		u32* maxptr = (u32*)(region + region_size);
-		// If our memory isn't a multiple of u32 then this won't write the last remaining bytes with anything
-		// Less than optimal, but there would be nothing we could do but throw a runtime warning anyway.
-		// AArch64: 0xD4200000 = BRK 0
-		while (ptr < maxptr)
-			*ptr++ = 0xD4200000;
-	}
+	void PoisonMemory(int offset) override;
 };
 }

Common/ArmEmitter.cpp

@@ -3211,10 +3211,10 @@ void ARMXEmitter::VCVTF16F32(ARMReg Dest, ARMReg Src) {
 
 // Always clear code space with breakpoints, so that if someone accidentally executes
 // uninitialized, it just breaks into the debugger.
-void ARMXCodeBlock::PoisonMemory() {
+void ARMXCodeBlock::PoisonMemory(int offset) {
 	// TODO: this isn't right for ARM!
-	memset(region, 0xCC, region_size);
-	ResetCodePtr();
+	memset(region + offset, 0xCC, region_size - offset);
+	ResetCodePtr(offset);
 }
 
 }

Common/ArmEmitter.h

@@ -895,7 +895,7 @@ public:
 
 class ARMXCodeBlock : public CodeBlock<ARMXEmitter> {
 public:
-	void PoisonMemory() override;
+	void PoisonMemory(int offset) override;
 };
 
 // VFP Specific

Common/CodeBlock.h

@@ -42,7 +42,7 @@ template<class T> class CodeBlock : public CodeBlockCommon, public T, NonCopyabl
 private:
 	// A privately used function to set the executable RAM space to something invalid.
 	// For debugging usefulness it should be used to set the RAM to a host specific breakpoint instruction
-	virtual void PoisonMemory() = 0;
+	virtual void PoisonMemory(int offset) = 0;
 
 public:
 	CodeBlock() : writeStart_(nullptr) {}
@@ -58,14 +58,13 @@ public:
 
 	// Always clear code space with breakpoints, so that if someone accidentally executes
 	// uninitialized, it just breaks into the debugger.
-	void ClearCodeSpace() {
+	void ClearCodeSpace(int offset) {
 		if (PlatformIsWXExclusive()) {
 			ProtectMemoryPages(region, region_size, MEM_PROT_READ | MEM_PROT_WRITE);
-		} else {
-			ProtectMemoryPages(region, region_size, MEM_PROT_READ | MEM_PROT_WRITE | MEM_PROT_EXEC);
 		}
-		PoisonMemory();
-		ResetCodePtr();
+		// If not WX Exclusive, no need to call ProtectMemoryPages because we never change the protection from RWX.
+		PoisonMemory(offset);
+		ResetCodePtr(offset);
 	}
 
 	// BeginWrite/EndWrite assume that we keep appending.
@@ -109,8 +108,8 @@ public:
 		return T::GetCodePointer();
 	}
 
-	void ResetCodePtr() {
-		T::SetCodePointer(region);
+	void ResetCodePtr(int offset) {
+		T::SetCodePointer(region + offset);
 	}
 
 	size_t GetSpaceLeft() const {

Common/MemoryUtil.cpp

@@ -17,6 +17,8 @@
 
 #include "ppsspp_config.h"
 
+#include "base/logging.h"
+
 #include "Common.h"
 #include "MemoryUtil.h"
 #include "StringUtils.h"

Common/Thunk.cpp

@@ -101,7 +101,7 @@ void ThunkManager::Init()
 void ThunkManager::Reset()
 {
 	thunks.clear();
-	ResetCodePtr();
+	ResetCodePtr(0);
 }
 
 void ThunkManager::Shutdown()

Common/x64Emitter.cpp

@@ -1980,9 +1980,9 @@ void XEmitter::FNSTSW_AX() { Write8(0xDF); Write8(0xE0); }
 
 void XEmitter::RDTSC() { Write8(0x0F); Write8(0x31); }
 
-void XCodeBlock::PoisonMemory() {
+void XCodeBlock::PoisonMemory(int offset) {
 	// x86/64: 0xCC = breakpoint
-	memset(region, 0xCC, region_size);
+	memset(region + offset, 0xCC, region_size - offset);
 }
 
 }

Common/x64Emitter.h

@@ -1061,7 +1061,7 @@ public:
 
 class XCodeBlock : public CodeBlock<XEmitter> {
 public:
-	void PoisonMemory() override;
+	void PoisonMemory(int offset) override;
 };
 
 }  // namespace

Core/MIPS/ARM/ArmJit.cpp

@@ -152,7 +152,7 @@ void ArmJit::FlushPrefixV()
 void ArmJit::ClearCache()
 {
 	blocks.Clear();
-	ClearCodeSpace();
+	ClearCodeSpace(0);
 	GenerateFixedCode();
 }
 

Core/MIPS/ARM64/Arm64Asm.cpp

@@ -318,10 +318,11 @@ void Arm64Jit::GenerateFixedCode(const JitOptions &jo) {
 		}
 	}
 
-	// Don't forget to zap the instruction cache! This must stay at the end of this function.
-	FlushIcache();
 	// Let's spare the pre-generated code from unprotect-reprotect.
 	AlignCodePage();
+	jitStartOffset = (int)(GetCodePtr() - start);
+	// Don't forget to zap the instruction cache! This must stay at the end of this function.
+	FlushIcache();
 	EndWrite();
 }
 

Core/MIPS/ARM64/Arm64Jit.cpp

@@ -142,8 +142,7 @@ void Arm64Jit::FlushPrefixV() {
 void Arm64Jit::ClearCache() {
 	ILOG("ARM64Jit: Clearing the cache!");
 	blocks.Clear();
-	ClearCodeSpace();
-	GenerateFixedCode(jo);
+	ClearCodeSpace(jitStartOffset);
 }
 
 void Arm64Jit::InvalidateCacheAt(u32 em_address, int length) {

Core/MIPS/ARM64/Arm64Jit.h

@@ -280,6 +280,8 @@ public:
 	const u8 *applyRoundingMode;
 	const u8 *updateRoundingMode;
 
+	int jitStartOffset;
+
 	// Indexed by FPCR FZ:RN bits for convenience.  Uses SCRATCH2.
 	const u8 *convertS0ToSCRATCH1[8];
 };

Core/MIPS/x86/Jit.cpp

@@ -219,7 +219,7 @@ void Jit::UpdateRoundingMode() {
 void Jit::ClearCache()
 {
 	blocks.Clear();
-	ClearCodeSpace();
+	ClearCodeSpace(0);
 	GenerateFixedCode(jo);
 }
 

Core/MIPS/x86/JitSafeMem.cpp

@@ -448,7 +448,7 @@ void JitSafeMemFuncs::Init(ThunkManager *thunks) {
 }
 
 void JitSafeMemFuncs::Shutdown() {
-	ResetCodePtr();
+	ResetCodePtr(0);
 	FreeCodeSpace();
 }
 

GPU/Common/VertexDecoderCommon.cpp

@@ -1281,5 +1281,5 @@ VertexDecoderJitCache::VertexDecoderJitCache()
 }
 
 void VertexDecoderJitCache::Clear() {
-	ClearCodeSpace();
+	ClearCodeSpace(0);
 }