Stay inside block when it's branch target is itself.

Source/BasicBlock.cpp

@@ -194,7 +194,23 @@ void CBasicBlock::CompileRange(CMipsJitter* jitter)
 		return;
 	}
 
+	bool loopsOnItself = [&]() {
+		if(m_begin == m_end)
+		{
+			return false;
+		}
+		uint32 branchInstAddr = m_end - 4;
+		uint32 inst = m_context.m_pMemoryMap->GetInstruction(branchInstAddr);
+		if(m_context.m_pArch->IsInstructionBranch(&m_context, branchInstAddr, inst) != MIPS_BRANCH_NORMAL)
+		{
+			return false;
+		}
+		uint32 target = m_context.m_pArch->GetInstructionEffectiveAddress(&m_context, branchInstAddr, inst);
+		return target == m_begin;
+	}();
+
 	CompileProlog(jitter);
+	jitter->MarkFirstBlockLabel();
 
 	for(uint32 address = m_begin; address <= m_end; address += 4)
 	{
@@ -206,8 +222,8 @@ void CBasicBlock::CompileRange(CMipsJitter* jitter)
 		assert(jitter->IsStackEmpty());
 	}
 
-	jitter->MarkFinalBlockLabel();
+	jitter->MarkLastBlockLabel();
-	CompileEpilog(jitter);
+	CompileEpilog(jitter, loopsOnItself);
 }
 
 void CBasicBlock::CompileProlog(CMipsJitter* jitter)
@@ -228,7 +244,7 @@ void CBasicBlock::CompileProlog(CMipsJitter* jitter)
 #endif
 }
 
-void CBasicBlock::CompileEpilog(CMipsJitter* jitter)
+void CBasicBlock::CompileEpilog(CMipsJitter* jitter, bool loopsOnItself)
 {
 	//Update cycle quota
 	jitter->PushRel(offsetof(CMIPS, m_State.cycleQuota));
@@ -258,15 +274,28 @@ void CBasicBlock::CompileEpilog(CMipsJitter* jitter)
 		jitter->PushCst(MIPS_INVALID_PC);
 		jitter->PullRel(offsetof(CMIPS, m_State.nDelayedJumpAddr));
 
-#if !defined(AOT_BUILD_CACHE) && !defined(__EMSCRIPTEN__)
+		if(loopsOnItself)
-		jitter->PushRel(offsetof(CMIPS, m_State.nHasException));
-		jitter->PushCst(0);
-		jitter->BeginIf(Jitter::CONDITION_EQ);
 		{
-			jitter->JumpToDynamic(reinterpret_cast<void*>(&NextBlockTrampoline));
+			jitter->PushRel(offsetof(CMIPS, m_State.nHasException));
+			jitter->PushCst(0);
+			jitter->BeginIf(Jitter::CONDITION_EQ);
+			{
+				jitter->Goto(jitter->GetFirstBlockLabel());
+			}
+			jitter->EndIf();
 		}
-		jitter->EndIf();
+		else
+		{
+#if !defined(AOT_BUILD_CACHE) && !defined(__EMSCRIPTEN__)
+			jitter->PushRel(offsetof(CMIPS, m_State.nHasException));
+			jitter->PushCst(0);
+			jitter->BeginIf(Jitter::CONDITION_EQ);
+			{
+				jitter->JumpToDynamic(reinterpret_cast<void*>(&NextBlockTrampoline));
+			}
+			jitter->EndIf();
 #endif
+		}
 	}
 	jitter->Else();
 	{

Source/BasicBlock.h

@@ -102,7 +102,7 @@ protected:
 	CMIPS& m_context;
 
 	virtual void CompileProlog(CMipsJitter*);
-	virtual void CompileEpilog(CMipsJitter*);
+	virtual void CompileEpilog(CMipsJitter*, bool);
 
 private:
 	void HandleExternalFunctionReference(uintptr_t, uint32, Jitter::CCodeGen::SYMBOL_REF_TYPE);

Source/MIPSInstructionFactory.cpp

@@ -180,7 +180,7 @@ void CMIPSInstructionFactory::BranchLikely(Jitter::CONDITION condition)
 	}
 	m_codeGen->Else();
 	{
-		m_codeGen->Goto(m_codeGen->GetFinalBlockLabel());
+		m_codeGen->Goto(m_codeGen->GetLastBlockLabel());
 	}
 	m_codeGen->EndIf();
 }

Source/MipsJitter.cpp

@@ -4,6 +4,7 @@
 
 CMipsJitter::CMipsJitter(Jitter::CCodeGen* codeGen)
     : CJitter(codeGen)
+    , m_firstBlockLabel(-1)
     , m_lastBlockLabel(-1)
 {
 	for(unsigned int i = 0; i < 4; i++)
@@ -17,6 +18,7 @@ CMipsJitter::CMipsJitter(Jitter::CCodeGen* codeGen)
 void CMipsJitter::Begin()
 {
 	CJitter::Begin();
+	m_firstBlockLabel = -1;
 	m_lastBlockLabel = -1;
 }
 
@@ -63,7 +65,13 @@ void CMipsJitter::PushRel64(size_t offset)
 	}
 }
 
-Jitter::CJitter::LABEL CMipsJitter::GetFinalBlockLabel()
+Jitter::CJitter::LABEL CMipsJitter::GetFirstBlockLabel()
+{
+	assert(m_firstBlockLabel != -1);
+	return m_firstBlockLabel;
+}
+
+Jitter::CJitter::LABEL CMipsJitter::GetLastBlockLabel()
 {
 	if(m_lastBlockLabel == -1)
 	{
@@ -72,7 +80,13 @@ Jitter::CJitter::LABEL CMipsJitter::GetFinalBlockLabel()
 	return m_lastBlockLabel;
 }
 
-void CMipsJitter::MarkFinalBlockLabel()
+void CMipsJitter::MarkFirstBlockLabel()
+{
+	m_firstBlockLabel = CreateLabel();
+	MarkLabel(m_firstBlockLabel);
+}
+
+void CMipsJitter::MarkLastBlockLabel()
 {
 	if(m_lastBlockLabel != -1)
 	{

Source/MipsJitter.h

@@ -15,8 +15,11 @@ public:
 
 	void SetVariableAsConstant(size_t, uint32);
 
-	LABEL GetFinalBlockLabel();
+	LABEL GetFirstBlockLabel();
-	void MarkFinalBlockLabel();
+	LABEL GetLastBlockLabel();
+
+	void MarkFirstBlockLabel();
+	void MarkLastBlockLabel();
 
 private:
 	struct VARIABLESTATUS
@@ -31,5 +34,6 @@ private:
 	void SetVariableStatus(size_t, const VARIABLESTATUS&);
 
 	VariableStatusMap m_variableStatus;
-	LABEL m_lastBlockLabel;
+	LABEL m_firstBlockLabel = -1;
+	LABEL m_lastBlockLabel = -1;
 };

Source/ee/EeBasicBlock.cpp

@@ -1,6 +1,6 @@
 #include "EeBasicBlock.h"
 
-void CEeBasicBlock::CompileEpilog(CMipsJitter* jitter)
+void CEeBasicBlock::CompileEpilog(CMipsJitter* jitter, bool loopsOnItself)
 {
 	if(IsIdleLoopBlock())
 	{
@@ -8,7 +8,7 @@ void CEeBasicBlock::CompileEpilog(CMipsJitter* jitter)
 		jitter->PullRel(offsetof(CMIPS, m_State.nHasException));
 	}
 
-	CBasicBlock::CompileEpilog(jitter);
+	CBasicBlock::CompileEpilog(jitter, loopsOnItself);
 }
 
 bool CEeBasicBlock::IsIdleLoopBlock() const

Source/ee/EeBasicBlock.h

@@ -8,7 +8,7 @@ public:
 	using CBasicBlock::CBasicBlock;
 
 protected:
-	void CompileEpilog(CMipsJitter*) override;
+	void CompileEpilog(CMipsJitter*, bool) override;
 
 private:
 	bool IsIdleLoopBlock() const;

Source/ee/VuBasicBlock.cpp

@@ -217,7 +217,7 @@ void CVuBasicBlock::CompileRange(CMipsJitter* jitter)
 		jitter->PullRel(offsetof(CMIPS, m_State.pipeTime));
 	}
 
-	CompileEpilog(jitter);
+	CompileEpilog(jitter, false);
 }
 
 bool CVuBasicBlock::IsConditionalBranch(uint32 opcodeLo)