[AMDGPU] Simplify SIInstrInfo::isLegalToSwap. NFC. (#149058)

Author: jayfoad

llvm/lib/Target/AMDGPU/SIInstrInfo.cpp

@@ -2733,49 +2733,47 @@ static MachineInstr *swapImmOperands(MachineInstr &MI,
 }
 
 bool SIInstrInfo::isLegalToSwap(const MachineInstr &MI, unsigned OpIdx0,
-                                const MachineOperand *MO0, unsigned OpIdx1,
-                                const MachineOperand *MO1) const {
+                                unsigned OpIdx1) const {
   const MCInstrDesc &InstDesc = MI.getDesc();
   const MCOperandInfo &OpInfo0 = InstDesc.operands()[OpIdx0];
   const MCOperandInfo &OpInfo1 = InstDesc.operands()[OpIdx1];
-  const TargetRegisterClass *DefinedRC1 =
-      OpInfo1.RegClass != -1 ? RI.getRegClass(OpInfo1.RegClass) : nullptr;
-  const TargetRegisterClass *DefinedRC0 =
-      OpInfo1.RegClass != -1 ? RI.getRegClass(OpInfo0.RegClass) : nullptr;
 
   unsigned Opc = MI.getOpcode();
   int Src0Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src0);
 
+  const MachineOperand &MO0 = MI.getOperand(OpIdx0);
+  const MachineOperand &MO1 = MI.getOperand(OpIdx1);
+
   // Swap doesn't breach constant bus or literal limits
   // It may move literal to position other than src0, this is not allowed
   // pre-gfx10 However, most test cases need literals in Src0 for VOP
   // FIXME: After gfx9, literal can be in place other than Src0
   if (isVALU(MI)) {
-    if ((int)OpIdx0 == Src0Idx && !MO0->isReg() &&
-        !isInlineConstant(*MO0, OpInfo1))
+    if ((int)OpIdx0 == Src0Idx && !MO0.isReg() &&
+        !isInlineConstant(MO0, OpInfo1))
       return false;
-    if ((int)OpIdx1 == Src0Idx && !MO1->isReg() &&
-        !isInlineConstant(*MO1, OpInfo0))
+    if ((int)OpIdx1 == Src0Idx && !MO1.isReg() &&
+        !isInlineConstant(MO1, OpInfo0))
       return false;
   }
 
-  if ((int)OpIdx1 != Src0Idx && MO0->isReg()) {
-    if (!DefinedRC1)
+  if ((int)OpIdx1 != Src0Idx && MO0.isReg()) {
+    if (OpInfo1.RegClass == -1)
       return OpInfo1.OperandType == MCOI::OPERAND_UNKNOWN;
-    return isLegalRegOperand(MI, OpIdx1, *MO0) &&
-           (!MO1->isReg() || isLegalRegOperand(MI, OpIdx0, *MO1));
+    return isLegalRegOperand(MI, OpIdx1, MO0) &&
+           (!MO1.isReg() || isLegalRegOperand(MI, OpIdx0, MO1));
   }
-  if ((int)OpIdx0 != Src0Idx && MO1->isReg()) {
-    if (!DefinedRC0)
+  if ((int)OpIdx0 != Src0Idx && MO1.isReg()) {
+    if (OpInfo0.RegClass == -1)
       return OpInfo0.OperandType == MCOI::OPERAND_UNKNOWN;
-    return (!MO0->isReg() || isLegalRegOperand(MI, OpIdx1, *MO0)) &&
-           isLegalRegOperand(MI, OpIdx0, *MO1);
+    return (!MO0.isReg() || isLegalRegOperand(MI, OpIdx1, MO0)) &&
+           isLegalRegOperand(MI, OpIdx0, MO1);
   }
 
   // No need to check 64-bit literals since swapping does not bring new
   // 64-bit literals into current instruction to fold to 32-bit
 
-  return isImmOperandLegal(MI, OpIdx1, *MO0);
+  return isImmOperandLegal(MI, OpIdx1, MO0);
 }
 
 MachineInstr *SIInstrInfo::commuteInstructionImpl(MachineInstr &MI, bool NewMI,
@@ -2797,12 +2795,12 @@ MachineInstr *SIInstrInfo::commuteInstructionImpl(MachineInstr &MI, bool NewMI,
            static_cast<int>(Src1Idx) &&
          "inconsistency with findCommutedOpIndices");
 
-  MachineOperand &Src0 = MI.getOperand(Src0Idx);
-  MachineOperand &Src1 = MI.getOperand(Src1Idx);
-  if (!isLegalToSwap(MI, Src0Idx, &Src0, Src1Idx, &Src1)) {
+  if (!isLegalToSwap(MI, Src0Idx, Src1Idx))
     return nullptr;
-  }
+
   MachineInstr *CommutedMI = nullptr;
+  MachineOperand &Src0 = MI.getOperand(Src0Idx);
+  MachineOperand &Src1 = MI.getOperand(Src1Idx);
   if (Src0.isReg() && Src1.isReg()) {
     // Be sure to copy the source modifiers to the right place.
     CommutedMI =

llvm/lib/Target/AMDGPU/SIInstrInfo.h

@@ -197,8 +197,7 @@ class SIInstrInfo final : public AMDGPUGenInstrInfo {
                            AMDGPU::OpName Src0OpName, MachineOperand &Src1,
                            AMDGPU::OpName Src1OpName) const;
   bool isLegalToSwap(const MachineInstr &MI, unsigned fromIdx,
-                     const MachineOperand *fromMO, unsigned toIdx,
-                     const MachineOperand *toMO) const;
+                     unsigned toIdx) const;
   MachineInstr *commuteInstructionImpl(MachineInstr &MI, bool NewMI,
                                        unsigned OpIdx0,
                                        unsigned OpIdx1) const override;