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

[Matt Arsenault via llvm-commits]

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@@ -1088,6 +1088,10 @@ Value *SplitPtrStructs::handleMemoryInst(Instruction *I, Value *Arg, Value *Ptr,
     Aux |= (Aux & AMDGPU::CPol::GLC ? AMDGPU::CPol::DLC : 0);
   if (IsVolatile)
     Aux |= AMDGPU::CPol::VOLATILE;
+  if (I->hasMetadata("amdgpu.last.use"))
+    Aux |= AMDGPU::CPol::TH_LU;
+  if (I->hasMetadata("nontemporal"))
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arsenm wrote:

Use the enum MD_nontemporal form 

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