[llvm] [AMDGPU] Handle nontemporal and amdgpu.last.use metadata in amdgpu-lower-buffer-fat-pointers (PR #120139)

[Acim Maravic via llvm-commits]

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@@ -1074,18 +1074,6 @@ Value *SplitPtrStructs::handleMemoryInst(Instruction *I, Value *Arg, Value *Ptr,
   Args.push_back(IRB.getInt32(0));
 
   uint32_t Aux = 0;
-  bool IsInvariant =
-      (isa<LoadInst>(I) && I->getMetadata(LLVMContext::MD_invariant_load));
-  bool IsNonTemporal = I->getMetadata(LLVMContext::MD_nontemporal);
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Acim-Maravic wrote:

Before GFX12, nontemporal was marked as GLC+SLC. This pass was coping Metadata to an intrinsic, and that Metadata is handled by SIMemoryLegalizer, the only problem was that during instruction selection, metadata was not copied (it was lost), so SIMemoryLegalizer was not able to handle it afterwards. 

https://github.com/llvm/llvm-project/pull/120139