[llvm] [AMDGPU] Drop !noundef when widening sub-DWORD constant loads (PR #201085)

[Matt Arsenault via llvm-commits]

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@@ -30,6 +31,22 @@ Align getAlign(const DataLayout &DL, const GlobalVariable *GV) {
                                        GV->getValueType());
 }
 
+void copyMetadataForWidenedLoad(LoadInst &Dest, const LoadInst &Source) {
+  SmallVector<std::pair<unsigned, MDNode *>, 8> MD;
+  Source.getAllMetadata(MD);
+  for (const auto &[ID, N] : MD) {
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arsenm wrote:

```suggestion
  for (const auto [ID, N] : MD) {
```

https://github.com/llvm/llvm-project/pull/201085