[llvm] [CodeGen] Don't derive MODereferenceable from !dereferenceable metadata (PR #222069)

[Alex MacLean via llvm-commits]

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@@ -2355,7 +2355,6 @@ FastISel::createMachineMemOperandFor(const Instruction *I) const {
 
   bool IsNonTemporal = I->hasMetadata(LLVMContext::MD_nontemporal);
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AlexMaclean wrote:

Good point, certainly worth considering using getLoadMemOperandFlags + getStoreMemOperandFlags but it sounds like there is a bit of a tradeoff on compile time. Since this would have other behavior impacts as well (ORing in getTargetMMOFlags for example), I'd prefer to keep this PR limited to the dereferencable fix. 

https://github.com/llvm/llvm-project/pull/222069