Merge pull request #18165 from unknownbrackets/x64-ir-bmi2

x86jit: Fix flush for special-purpose reg
hrydgard · Sep 17, 2023 · 92d1a66 · 92d1a66
2 parents 99b2d2b + 07150b5
commit 92d1a66
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Showing 2 changed files with 19 additions and 8 deletions.
diff --git a/Core/MIPS/IR/IRFrontend.cpp b/Core/MIPS/IR/IRFrontend.cpp
@@ -339,8 +339,8 @@ void IRFrontend::CheckBreakpoint(u32 addr) {
 	if (CBreakPoints::IsAddressBreakPoint(addr)) {
 		FlushAll();
 
-		if (GetCompilerPC() != js.blockStart)
-			ir.Write(IROp::SetPCConst, 0, ir.AddConstant(GetCompilerPC()));
+		// Can't skip this even at the start of a block, might impact block linking.
+		ir.Write(IROp::SetPCConst, 0, ir.AddConstant(GetCompilerPC()));
 
 		RestoreRoundingMode();
 		// At this point, downcount HAS the delay slot, but not the instruction itself.
@@ -370,8 +370,8 @@ void IRFrontend::CheckMemoryBreakpoint(int rs, int offset) {
 	if (CBreakPoints::HasMemChecks()) {
 		FlushAll();
 
-		if (GetCompilerPC() != js.blockStart)
-			ir.Write(IROp::SetPCConst, 0, ir.AddConstant(GetCompilerPC()));
+		// Can't skip this even at the start of a block, might impact block linking.
+		ir.Write(IROp::SetPCConst, 0, ir.AddConstant(GetCompilerPC()));
 
 		RestoreRoundingMode();
 		// At this point, downcount HAS the delay slot, but not the instruction itself.

diff --git a/Core/MIPS/x86/X64IRRegCache.cpp b/Core/MIPS/x86/X64IRRegCache.cpp
@@ -222,14 +222,25 @@ void X64IRRegCache::MapWithFlags(IRInst inst, X64Map destFlags, X64Map src1Flags
 	mapping[2].flags = mapping[2].flags | src2Flags;
 
 	auto flushReg = [&](IRNativeReg nreg) {
+		bool mustKeep = false;
+		bool canDiscard = false;
 		for (int i = 0; i < 3; ++i) {
-			if (mapping[i].reg == nr[nreg].mipsReg && (mapping[i].flags & MIPSMap::NOINIT) == MIPSMap::NOINIT) {
-				DiscardNativeReg(nreg);
-				return;
+			if (mapping[i].reg != nr[nreg].mipsReg)
+				continue;
+
+			if ((mapping[i].flags & MIPSMap::NOINIT) != MIPSMap::NOINIT) {
+				mustKeep = true;
+				break;
+			} else {
+				canDiscard = true;
 			}
 		}
 
-		FlushNativeReg(nreg);
+		if (mustKeep || !canDiscard) {
+			FlushNativeReg(nreg);
+		} else {
+			DiscardNativeReg(nreg);
+		}
 	};
 
 	// If there are any special rules, we might need to spill.