Use faster CheckGatherPipe from JIT.

We don't need to profile explicit calls to CheckGatherPipe: we aleady know
where they are. Skip profiling, and explciitly insert an exception check.

While I'm here, get rid of unused code in JitIL.

Source/Core/Core/HW/GPFifo.cpp

@@ -55,37 +55,50 @@ void ResetGatherPipe()
 	m_gatherPipeCount = 0;
 }
 
+static void UpdateGatherPipe()
+{
+	u32 cnt;
+	u8* curMem = Memory::GetPointer(ProcessorInterface::Fifo_CPUWritePointer);
+	for (cnt = 0; m_gatherPipeCount >= GATHER_PIPE_SIZE; cnt += GATHER_PIPE_SIZE)
+	{
+		// copy the GatherPipe
+		memcpy(curMem, m_gatherPipe + cnt, GATHER_PIPE_SIZE);
+		m_gatherPipeCount -= GATHER_PIPE_SIZE;
+
+		// increase the CPUWritePointer
+		if (ProcessorInterface::Fifo_CPUWritePointer == ProcessorInterface::Fifo_CPUEnd)
+		{
+			ProcessorInterface::Fifo_CPUWritePointer = ProcessorInterface::Fifo_CPUBase;
+			curMem = Memory::GetPointer(ProcessorInterface::Fifo_CPUWritePointer);
+		}
+		else
+		{
+			curMem += GATHER_PIPE_SIZE;
+			ProcessorInterface::Fifo_CPUWritePointer += GATHER_PIPE_SIZE;
+		}
+
+		g_video_backend->Video_GatherPipeBursted();
+	}
+
+	// move back the spill bytes
+	memmove(m_gatherPipe, m_gatherPipe + cnt, m_gatherPipeCount);
+}
+
+void FastCheckGatherPipe()
+{
+	if (m_gatherPipeCount >= GATHER_PIPE_SIZE)
+	{
+		UpdateGatherPipe();
+	}
+}
+
 void CheckGatherPipe()
 {
 	if (m_gatherPipeCount >= GATHER_PIPE_SIZE)
 	{
-		u32 cnt;
+		UpdateGatherPipe();
-		u8* curMem = Memory::GetPointer(ProcessorInterface::Fifo_CPUWritePointer);
-		for (cnt = 0; m_gatherPipeCount >= GATHER_PIPE_SIZE; cnt += GATHER_PIPE_SIZE)
-		{
-			// copy the GatherPipe
-			memcpy(curMem, m_gatherPipe + cnt, GATHER_PIPE_SIZE);
-			m_gatherPipeCount -= GATHER_PIPE_SIZE;
 
-			// increase the CPUWritePointer
+		// Profile where slow FIFO writes are occurring.
-			if (ProcessorInterface::Fifo_CPUWritePointer == ProcessorInterface::Fifo_CPUEnd)
-			{
-				ProcessorInterface::Fifo_CPUWritePointer = ProcessorInterface::Fifo_CPUBase;
-				curMem = Memory::GetPointer(ProcessorInterface::Fifo_CPUWritePointer);
-			}
-			else
-			{
-				curMem += GATHER_PIPE_SIZE;
-				ProcessorInterface::Fifo_CPUWritePointer += GATHER_PIPE_SIZE;
-			}
-
-			g_video_backend->Video_GatherPipeBursted();
-		}
-
-		// move back the spill bytes
-		memmove(m_gatherPipe, m_gatherPipe + cnt, m_gatherPipeCount);
-
-		// Profile where the FIFO writes are occurring.
 		JitInterface::CompileExceptionCheck(JitInterface::ExceptionType::EXCEPTIONS_FIFO_WRITE);
 	}
 }

Source/Core/Core/HW/GPFifo.h

@@ -27,6 +27,7 @@ void DoState(PointerWrap &p);
 // ResetGatherPipe
 void ResetGatherPipe();
 void CheckGatherPipe();
+void FastCheckGatherPipe();
 
 bool IsEmpty();
 

Source/Core/Core/PowerPC/Jit64/Jit.cpp

@@ -300,7 +300,7 @@ bool Jit64::Cleanup()
 	if (jo.optimizeGatherPipe && js.fifoBytesThisBlock > 0)
 	{
 		ABI_PushRegistersAndAdjustStack({}, 0);
-		ABI_CallFunction((void *)&GPFifo::CheckGatherPipe);
+		ABI_CallFunction((void *)&GPFifo::FastCheckGatherPipe);
 		ABI_PopRegistersAndAdjustStack({}, 0);
 		did_something = true;
 	}
@@ -665,14 +665,44 @@ const u8* Jit64::DoJit(u32 em_address, PPCAnalyst::CodeBuffer *code_buf, JitBloc
 			js.isLastInstruction = true;
 		}
 
+		// Gather pipe writes using a non-immediate address are discovered by profiling.
+		bool gatherPipeIntCheck = jit->js.fifoWriteAddresses.find(ops[i].address) != jit->js.fifoWriteAddresses.end();
+
+		// Gather pipe writes using an immediate address are explicitly tracked.
 		if (jo.optimizeGatherPipe && js.fifoBytesThisBlock >= 32)
 		{
 			js.fifoBytesThisBlock -= 32;
-			MOV(32, PPCSTATE(pc), Imm32(jit->js.compilerPC)); // Helps external systems know which instruction triggered the write
 			BitSet32 registersInUse = CallerSavedRegistersInUse();
 			ABI_PushRegistersAndAdjustStack(registersInUse, 0);
-			ABI_CallFunction((void *)&GPFifo::CheckGatherPipe);
+			ABI_CallFunction((void *)&GPFifo::FastCheckGatherPipe);
 			ABI_PopRegistersAndAdjustStack(registersInUse, 0);
+			gatherPipeIntCheck = true;
+		}
+
+		// Gather pipe writes can generate an exception; add an exception check.
+		// TODO: This doesn't really match hardware; the CP interrupt is
+		// asynchronous.
+		if (gatherPipeIntCheck)
+		{
+			TEST(32, PPCSTATE(Exceptions), Imm32(EXCEPTION_EXTERNAL_INT));
+			FixupBranch extException = J_CC(CC_NZ, true);
+			SwitchToFarCode();
+			SetJumpTarget(extException);
+			TEST(32, PPCSTATE(msr), Imm32(0x0008000));
+			FixupBranch noExtIntEnable = J_CC(CC_Z, true);
+			TEST(32, M(&ProcessorInterface::m_InterruptCause), Imm32(ProcessorInterface::INT_CAUSE_CP | ProcessorInterface::INT_CAUSE_PE_TOKEN | ProcessorInterface::INT_CAUSE_PE_FINISH));
+			FixupBranch noCPInt = J_CC(CC_Z, true);
+
+			gpr.Flush(FLUSH_MAINTAIN_STATE);
+			fpr.Flush(FLUSH_MAINTAIN_STATE);
+
+			MOV(32, PPCSTATE(pc), Imm32(ops[i].address));
+			WriteExternalExceptionExit();
+
+			SwitchToNearCode();
+
+			SetJumpTarget(noCPInt);
+			SetJumpTarget(noExtIntEnable);
 		}
 
 		u32 function = HLE::GetFunctionIndex(ops[i].address);
@@ -718,33 +748,6 @@ const u8* Jit64::DoJit(u32 em_address, PPCAnalyst::CodeBuffer *code_buf, JitBloc
 				js.firstFPInstructionFound = true;
 			}
 
-			// Add an external exception check if the instruction writes to the FIFO.
-			if (jit->js.fifoWriteAddresses.find(ops[i].address) != jit->js.fifoWriteAddresses.end())
-			{
-				TEST(32, PPCSTATE(Exceptions), Imm32(EXCEPTION_ISI | EXCEPTION_PROGRAM | EXCEPTION_SYSCALL | EXCEPTION_FPU_UNAVAILABLE | EXCEPTION_DSI | EXCEPTION_ALIGNMENT));
-				FixupBranch clearInt = J_CC(CC_NZ);
-				TEST(32, PPCSTATE(Exceptions), Imm32(EXCEPTION_EXTERNAL_INT));
-				FixupBranch extException = J_CC(CC_NZ, true);
-				SwitchToFarCode();
-				SetJumpTarget(extException);
-				TEST(32, PPCSTATE(msr), Imm32(0x0008000));
-				FixupBranch noExtIntEnable = J_CC(CC_Z, true);
-				TEST(32, M(&ProcessorInterface::m_InterruptCause), Imm32(ProcessorInterface::INT_CAUSE_CP | ProcessorInterface::INT_CAUSE_PE_TOKEN | ProcessorInterface::INT_CAUSE_PE_FINISH));
-				FixupBranch noCPInt = J_CC(CC_Z, true);
-
-				gpr.Flush(FLUSH_MAINTAIN_STATE);
-				fpr.Flush(FLUSH_MAINTAIN_STATE);
-
-				MOV(32, PPCSTATE(pc), Imm32(ops[i].address));
-				WriteExternalExceptionExit();
-
-				SwitchToNearCode();
-
-				SetJumpTarget(noCPInt);
-				SetJumpTarget(noExtIntEnable);
-				SetJumpTarget(clearInt);
-			}
-
 			if (SConfig::GetInstance().m_LocalCoreStartupParameter.bEnableDebugging && breakpoints.IsAddressBreakPoint(ops[i].address) && GetState() != CPU_STEPPING)
 			{
 				// Turn off block linking if there are breakpoints so that the Step Over command does not link this block.

Source/Core/Core/PowerPC/Jit64IL/JitIL.cpp

@@ -361,11 +361,6 @@ static void ImHere()
 
 void JitIL::Cleanup()
 {
-	if (jo.optimizeGatherPipe && js.fifoBytesThisBlock > 0)
-	{
-		ABI_CallFunction((void *)&GPFifo::CheckGatherPipe);
-	}
-
 	// SPEED HACK: MMCR0/MMCR1 should be checked at run-time, not at compile time.
 	if (MMCR0.Hex || MMCR1.Hex)
 		ABI_CallFunctionCCC((void *)&PowerPC::UpdatePerformanceMonitor, js.downcountAmount, jit->js.numLoadStoreInst, jit->js.numFloatingPointInst);

Source/Core/Core/PowerPC/JitArm32/Jit.cpp

@@ -123,7 +123,7 @@ void JitArm::Cleanup()
 	if (jo.optimizeGatherPipe && js.fifoBytesThisBlock > 0)
 	{
 		PUSH(4, R0, R1, R2, R3);
-		QuickCallFunction(R14, (void*)&GPFifo::CheckGatherPipe);
+		QuickCallFunction(R14, (void*)&GPFifo::FastCheckGatherPipe);
 		POP(4, R0, R1, R2, R3);
 	}
 }
@@ -465,7 +465,7 @@ const u8* JitArm::DoJit(u32 em_address, PPCAnalyst::CodeBuffer *code_buf, JitBlo
 		{
 			js.fifoBytesThisBlock -= 32;
 			PUSH(4, R0, R1, R2, R3);
-			QuickCallFunction(R14, (void*)&GPFifo::CheckGatherPipe);
+			QuickCallFunction(R14, (void*)&GPFifo::FastCheckGatherPipe);
 			POP(4, R0, R1, R2, R3);
 		}
 

Source/Core/Core/PowerPC/JitArm64/Jit.cpp

@@ -292,7 +292,7 @@ const u8* JitArm64::DoJit(u32 em_address, PPCAnalyst::CodeBuffer *code_buf, JitB
 			regs_in_use[W30] = 0;
 
 			ABI_PushRegisters(regs_in_use);
-			MOVI2R(X30, (u64)&GPFifo::CheckGatherPipe);
+			MOVI2R(X30, (u64)&GPFifo::FastCheckGatherPipe);
 			BLR(X30);
 			ABI_PopRegisters(regs_in_use);
 			gpr.Unlock(W30);