[llvm] Add AMDGPU metadata to copyMetadataForLoad() (PR #110720)

[Matt Arsenault via llvm-commits]

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@@ -3488,6 +3490,14 @@ void llvm::copyMetadataForLoad(LoadInst &Dest, const LoadInst &Source) {
       copyRangeMetadata(DL, Source, N, Dest);
       break;
     }
+    // Extended last-use / nontemporal hint on AMD GPUs
+    if (ID == Ctx.getMDKindID("amdpu.last.use"))
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arsenm wrote:

Is this the one that we want to parameterize !nontemporal for? Probably should just do that? 

https://github.com/llvm/llvm-project/pull/110720