[llvm] [AMDGPU][MC] Support src modifiers for v_mov_b32 and v_movrel* instructions (PR #76498)

Thu Jan 18 05:47:22 PST 2024

================
@@ -3309,6 +3310,14 @@ bool SIInstrInfo::isFoldableCopy(const MachineInstr &MI) {
   case AMDGPU::V_ACCVGPR_READ_B32_e64:
   case AMDGPU::V_ACCVGPR_MOV_B32:
     return true;
+  case AMDGPU::V_MOV_B32_e64:
+    if (MI
+            .getOperand(AMDGPU::getNamedOperandIdx(
+                AMDGPU::V_MOV_B32_e64, AMDGPU::OpName::src0_modifiers))
+            .getImm() == 0)
+      return true;
+    else
+      return false;
----------------
mbrkusanin wrote:

```suggestion
  case AMDGPU::V_MOV_B32_e64: {
    int16_t Idx = AMDGPU::getNamedOperandIdx(AMDGPU::V_MOV_B32_e64,
                                             AMDGPU::OpName::src0_modifiers);
    return MI.getOperand(Idx).getImm() == SISrcMods::NONE;
  }
```

https://github.com/llvm/llvm-project/pull/76498
