[PATCH] D130885: [AtomicExpandPass] Always copy pcsections Metadata to expanded atomics

[Marco Elver via Phabricator via llvm-commits]

melver added inline comments.


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Comment at: llvm/lib/CodeGen/AtomicExpandPass.cpp:130-133
+  // Preserves the DebugLoc from I, and preserves still valid metadata.
+  explicit ReplacementIRBuilder(Instruction *I) : IRBuilder<>(I) {
+    this->CollectMetadataToCopy(I, {LLVMContext::MD_pcsections});
+  }
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arsenm wrote:
> This seems too specific. Why do we need a new IRBuilder subclass just for this? Isn't there already an existing helper for metadata? We could also preserve a lot more metadata, like any aliasing info
There's no existing helper (except CollectMetadataToCopy()) AFAIK.

The alternative is to explicitly add a Builder.CollectMetadataToCopy everywhere, but I felt that this is more concise given it's done everywhere.

This subclass is only available to AtomicExpandPass. I tried to have a local BuildIRBuilder() function, but IR builder doesn't like being copied. Having a subclass that does something extra in the constructor seemed just as elegant and simple.


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130885/new/

https://reviews.llvm.org/D130885