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

[Krzysztof Drewniak 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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krzysz00 wrote:

That GLC/DLC is what's used to implement nontemporal, no? It was in the lowering logic up in LLPC when I copied from it.

If we're removing adding that data here, I'd like pointers in code - and tests for, if we don't have them - to setting glc/dlc in both SelectionDAG and GlobalISel's handling of the intrinsics

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