AMDGPU: Remove override of TargetInstrInfo::getRegClass

This should not be overridable and the special case hacks
have been replaced with RegClassByHwMode

Author: arsenm

llvm/lib/Target/AMDGPU/SIInstrInfo.cpp

@@ -5954,19 +5954,6 @@ SIInstrInfo::getWholeWaveFunctionSetup(MachineFunction &MF) const {
   llvm_unreachable("Couldn't find SI_SETUP_WHOLE_WAVE_FUNC instruction");
 }
 
-// FIXME: This should not be an overridable function. All subtarget dependent
-// operand modifications should go through isLookupRegClassByHwMode in the
-// generic handling.
-const TargetRegisterClass *
-SIInstrInfo::getRegClass(const MCInstrDesc &TID, unsigned OpNum,
-                         const TargetRegisterInfo *TRI) const {
-  if (OpNum >= TID.getNumOperands())
-    return nullptr;
-  const MCOperandInfo &OpInfo = TID.operands()[OpNum];
-  int16_t RegClass = getOpRegClassID(OpInfo);
-  return RegClass < 0 ? nullptr : RI.getRegClass(RegClass);
-}
-
 const TargetRegisterClass *SIInstrInfo::getOpRegClass(const MachineInstr &MI,
                                                       unsigned OpNo) const {
   const MCInstrDesc &Desc = get(MI.getOpcode());

llvm/lib/Target/AMDGPU/SIInstrInfo.h

@@ -1539,10 +1539,6 @@ class SIInstrInfo final : public AMDGPUGenInstrInfo {
   /// Return true if this opcode should not be used by codegen.
   bool isAsmOnlyOpcode(int MCOp) const;
 
-  const TargetRegisterClass *
-  getRegClass(const MCInstrDesc &TID, unsigned OpNum,
-              const TargetRegisterInfo *TRI) const override;
-
   void fixImplicitOperands(MachineInstr &MI) const;
 
   MachineInstr *foldMemoryOperandImpl(MachineFunction &MF, MachineInstr &MI,