[PATCH] D97244: [SimplifyCFG] Update passingValueIsAlwaysUndefined to check more attributes

[Guozhi Wei via Phabricator via llvm-commits]

Carrot added inline comments.


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Comment at: llvm/include/llvm/IR/InstrTypes.h:1663
+           paramHasAttr(ArgNo, Attribute::Dereferenceable) ||
+           // dereferenceable implies noundef, and null is a well-defined value.
+           paramHasAttr(ArgNo, Attribute::DereferenceableOrNull);
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It is not true for "this" parameter. It always has dereferenceable and nonnull attribute, if "this" is not used in the function, passing in undef is no problem.

It causes wrong code generated for our application.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D97244/new/

https://reviews.llvm.org/D97244