[llvm] [RFC] Memory Model Relaxation Annotations (PR #78569)

[Pierre van Houtryve via llvm-commits]

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@@ -132,7 +132,8 @@ struct ReplacementIRBuilder : IRBuilder<InstSimplifyFolder> {
   explicit ReplacementIRBuilder(Instruction *I, const DataLayout &DL)
       : IRBuilder(I->getContext(), DL) {
     SetInsertPoint(I);
-    this->CollectMetadataToCopy(I, {LLVMContext::MD_pcsections});
+    this->CollectMetadataToCopy(
+        I, {LLVMContext::MD_pcsections, LLVMContext::MD_mmra});
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Pierre-vh wrote:

The pass is quite big, adding explicit copies will require some refactoring (to make sure all helpers can access the original MD).

I understand if the IRBuilder change needed is too much. Would it be fine if I create a custom inserter in this pass and let that handle adding MMRAs, so the logic is contained to the pass, or do you really prefer explicit copying everywhere?

https://github.com/llvm/llvm-project/pull/78569