GlobalISel: Remove unnecessary check for copy type

COPY isn't allowed to change the type, but can mix no type with type.
llvm · Aug 17, 2020 · 924f31b · 924f31b
1 parent 66ffa0e
commit 924f31b
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Showing 2 changed files with 3 additions and 4 deletions.
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/Utils.h b/llvm/include/llvm/CodeGen/GlobalISel/Utils.h
@@ -151,9 +151,8 @@ const ConstantFP* getConstantFPVRegVal(Register VReg,
 MachineInstr *getOpcodeDef(unsigned Opcode, Register Reg,
                            const MachineRegisterInfo &MRI);
 
-/// Find the def instruction for \p Reg, folding away any trivial copies. Note
-/// it may still return a COPY, if it changes the type. May return nullptr if \p
-/// Reg is not a generic virtual register.
+/// Find the def instruction for \p Reg, folding away any trivial copies. May
+/// return nullptr if \p Reg is not a generic virtual register.
 MachineInstr *getDefIgnoringCopies(Register Reg,
                                    const MachineRegisterInfo &MRI);
 

diff --git a/llvm/lib/CodeGen/GlobalISel/Utils.cpp b/llvm/lib/CodeGen/GlobalISel/Utils.cpp
@@ -365,7 +365,7 @@ getDefSrcRegIgnoringCopies(Register Reg, const MachineRegisterInfo &MRI) {
   while (DefMI->getOpcode() == TargetOpcode::COPY) {
     Register SrcReg = DefMI->getOperand(1).getReg();
     auto SrcTy = MRI.getType(SrcReg);
-    if (!SrcTy.isValid() || SrcTy != DstTy)
+    if (!SrcTy.isValid())
       break;
     DefMI = MRI.getVRegDef(SrcReg);
     DefSrcReg = SrcReg;