[PATCH] D93840: [InstCombine] Disable unsafe select transform behind a flag

[Nikita Popov via Phabricator via llvm-commits]

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This disables the poison-unsafe select -> and/or transform behind a flag (we continue to perform the fold by default). This is intended to simplify testing while we add support for the select pattern. Otherwise, there's no way to test InstCombine-related changes, as InstCombine would just canonicalize it away.

This only disables the main select -> and/or transform. A number of related ones are instead changed to canonicalize to the a ? b : false and a ? true : b forms which represent and/or respectively. This requires a bit of care to avoid infinite loops, as we do not want !a ? b : false to be converted into a ? false : b.

The basic idea here is the same as D93065 <https://reviews.llvm.org/D93065>, this just keeps it behind a flag, and retains the canonicalizations.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D93840

Files:
  llvm/include/llvm/Transforms/InstCombine/InstCombiner.h
  llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
  llvm/test/Transforms/InstCombine/select-and-or.ll

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