[AMDGPU] Move S_ADD_U64_PSEUDO handling into getVALUOp. NFC. (llvm#142934)

S_ADD_U64_PSEUDO and S_SUB_U64_PSEUDO are not "special cases" so can be
handled in getVALUOp instead of moveToVALUImpl.

Author: jayfoad

llvm/lib/Target/AMDGPU/SIInstrInfo.cpp

@@ -5528,6 +5528,10 @@ unsigned SIInstrInfo::getVALUOp(const MachineInstr &MI) const {
     return AMDGPU::V_ADD_CO_U32_e32;
   case AMDGPU::S_SUB_U32:
     return AMDGPU::V_SUB_CO_U32_e32;
+  case AMDGPU::S_ADD_U64_PSEUDO:
+    return AMDGPU::V_ADD_U64_PSEUDO;
+  case AMDGPU::S_SUB_U64_PSEUDO:
+    return AMDGPU::V_SUB_U64_PSEUDO;
   case AMDGPU::S_SUBB_U32: return AMDGPU::V_SUBB_U32_e32;
   case AMDGPU::S_MUL_I32: return AMDGPU::V_MUL_LO_U32_e64;
   case AMDGPU::S_MUL_HI_U32: return AMDGPU::V_MUL_HI_U32_e64;
@@ -7310,12 +7314,6 @@ void SIInstrInfo::moveToVALUImpl(SIInstrWorklist &Worklist,
   switch (Opcode) {
   default:
     break;
-  case AMDGPU::S_ADD_U64_PSEUDO:
-    NewOpcode = AMDGPU::V_ADD_U64_PSEUDO;
-    break;
-  case AMDGPU::S_SUB_U64_PSEUDO:
-    NewOpcode = AMDGPU::V_SUB_U64_PSEUDO;
-    break;
   case AMDGPU::S_ADD_I32:
   case AMDGPU::S_SUB_I32: {
     // FIXME: The u32 versions currently selected use the carry.