1 files changed, 11 insertions, 7 deletions
diff --git a/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp b/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp
index 2ce1d414e7550..1e2a82615da8c 100644
--- a/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp
@@ -455,19 +455,23 @@ bool InlineAsmLowering::lowerInlineAsm(
         unsigned DefRegIdx = InstFlagIdx + 1;
         Register Def = Inst->getOperand(DefRegIdx).getReg();
 
-        // Copy input to new vreg with same reg class as Def
-        const TargetRegisterClass *RC = MRI->getRegClass(Def);
         ArrayRef<Register> SrcRegs = GetOrCreateVRegs(*OpInfo.CallOperandVal);
         assert(SrcRegs.size() == 1 && "Single register is expected here");
-        Register Tmp = MRI->createVirtualRegister(RC);
-        if (!buildAnyextOrCopy(Tmp, SrcRegs[0], MIRBuilder))
-          return false;
 
-        // Add Flag and input register operand (Tmp) to Inst. Tie Tmp to Def.
+        // When Def is physreg: use given input.
+        Register In = SrcRegs[0];
+        // When Def is vreg: copy input to new vreg with same reg class as Def.
+        if (Def.isVirtual()) {
+          In = MRI->createVirtualRegister(MRI->getRegClass(Def));
+          if (!buildAnyextOrCopy(In, SrcRegs[0], MIRBuilder))
+            return false;
+        }
+
+        // Add Flag and input register operand (In) to Inst. Tie In to Def.
         unsigned UseFlag = InlineAsm::getFlagWord(InlineAsm::Kind_RegUse, 1);
         unsigned Flag = InlineAsm::getFlagWordForMatchingOp(UseFlag, DefIdx);
         Inst.addImm(Flag);
-        Inst.addReg(Tmp);
+        Inst.addReg(In);
         Inst->tieOperands(DefRegIdx, Inst->getNumOperands() - 1);
         break;
       }