[PATCH] D106233: [InstCombine] Add freezeAllUsesOfArgument to visitFreeze

[Hyeongyu Kim via Phabricator via llvm-commits]

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In D106041 <https://reviews.llvm.org/D106041>, a freeze was added before the branch condition to solve the miscompilation problem of SimpleLoopUnswitch.
However, I found that the added freeze disturbed other optimizations in the following situations.

  arg.fr = freeze(arg)
  use(arg.fr)
  ...
  use(arg)

It is a problem that occurred when arg and arg.fr were recognized as different values.
Therefore, changing to use arg.fr instead of arg throughout the function eliminates the above problem.
Thus, I add a function that changes all uses of arg to freeze(arg) to visitFreeze of InstCombine.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D106233

Files:
  llvm/lib/Transforms/InstCombine/InstCombineInternal.h
  llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
  llvm/test/Transforms/InstCombine/freeze.ll

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