[llvm] [AMDGPU][CodeGen] LocalStackSlotAllocation: record per-instr FI offsets (PR #166979)

[Jay Foad via llvm-commits]

================
@@ -346,7 +350,10 @@ bool LocalStackSlotImpl::insertFrameReferenceRegisters(MachineFunction &Fn) {
           int64_t LocalOffset = LocalOffsets[Idx];
           if (!TRI->needsFrameBaseReg(&MI, LocalOffset))
             break;
-          FrameReferenceInsns.push_back(FrameRef(&MI, LocalOffset, Idx, Order++));
+          int64_t InstOffset =
+              TRI->getFrameIndexInstrOffset(&MI, MO.getOperandNo());
+          FrameReferenceInsns.push_back(
+              FrameRef(&MI, LocalOffset, Idx, InstOffset, Order++));
----------------
jayfoad wrote:

```suggestion
          FrameReferenceInsns.emplace_back(
              &MI, LocalOffset, Idx, InstOffset, Order++);
```

https://github.com/llvm/llvm-project/pull/166979