follow up patch

Author: broxigarchen

llvm/lib/Target/AMDGPU/SIFoldOperands.cpp

@@ -932,7 +932,7 @@ static MachineOperand *lookUpCopyChain(const SIInstrInfo &TII,
   for (MachineInstr *SubDef = MRI.getVRegDef(SrcReg);
        SubDef && TII.isFoldableCopy(*SubDef);
        SubDef = MRI.getVRegDef(Sub->getReg())) {
-    unsigned SrcIdx = TII.getFoldableCopySrcIdx(*SubDef);
+    const int SrcIdx = MovOp == AMDGPU::V_MOV_B16_t16_e64 ? 2 : 1;
     MachineOperand &SrcOp = SubDef->getOperand(SrcIdx);
 
     if (SrcOp.isImm())

llvm/lib/Target/AMDGPU/SIInstrInfo.cpp

@@ -3411,7 +3411,6 @@ void SIInstrInfo::insertSelect(MachineBasicBlock &MBB,
 bool SIInstrInfo::isFoldableCopy(const MachineInstr &MI) {
   switch (MI.getOpcode()) {
   case AMDGPU::V_MOV_B16_t16_e32:
-  case AMDGPU::V_MOV_B16_t16_e64:
   case AMDGPU::V_MOV_B32_e32:
   case AMDGPU::V_MOV_B32_e64:
   case AMDGPU::V_MOV_B64_PSEUDO:
@@ -3428,34 +3427,10 @@ bool SIInstrInfo::isFoldableCopy(const MachineInstr &MI) {
   case AMDGPU::AV_MOV_B32_IMM_PSEUDO:
   case AMDGPU::AV_MOV_B64_IMM_PSEUDO:
     return true;
-  default:
-    return false;
-  }
-}
-
-unsigned SIInstrInfo::getFoldableCopySrcIdx(const MachineInstr &MI) {
-  switch (MI.getOpcode()) {
-  case AMDGPU::V_MOV_B16_t16_e32:
   case AMDGPU::V_MOV_B16_t16_e64:
-    return 2;
-  case AMDGPU::V_MOV_B32_e32:
-  case AMDGPU::V_MOV_B32_e64:
-  case AMDGPU::V_MOV_B64_PSEUDO:
-  case AMDGPU::V_MOV_B64_e32:
-  case AMDGPU::V_MOV_B64_e64:
-  case AMDGPU::S_MOV_B32:
-  case AMDGPU::S_MOV_B64:
-  case AMDGPU::S_MOV_B64_IMM_PSEUDO:
-  case AMDGPU::COPY:
-  case AMDGPU::WWM_COPY:
-  case AMDGPU::V_ACCVGPR_WRITE_B32_e64:
-  case AMDGPU::V_ACCVGPR_READ_B32_e64:
-  case AMDGPU::V_ACCVGPR_MOV_B32:
-  case AMDGPU::AV_MOV_B32_IMM_PSEUDO:
-  case AMDGPU::AV_MOV_B64_IMM_PSEUDO:
-    return 1;
+    return !hasAnyModifiersSet(MI);
   default:
-    llvm_unreachable("MI is not a foldable copy");
+    return false;
   }
 }
 

llvm/lib/Target/AMDGPU/SIInstrInfo.h

@@ -417,7 +417,6 @@ class SIInstrInfo final : public AMDGPUGenInstrInfo {
                                   const MachineInstr &MIb) const override;
 
   static bool isFoldableCopy(const MachineInstr &MI);
-  static unsigned getFoldableCopySrcIdx(const MachineInstr &MI);
 
   void removeModOperands(MachineInstr &MI) const;