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

[Jay Foad 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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jayfoad wrote:

IsNonTemporal should be handled post-isel by SIMemoryLegalizer, which sets bits in the aux (aka `cpol`) operand based on flags in the MachineMemOperand. It also knows how to do it properly for different architectures, which this code does not - e.g. the meaning of the aux bits changes completely in GFX12.

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