[PATCH] D146274: [LICM] Do not hoist widenable conditions

[Max Kazantsev via Phabricator via llvm-commits]

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Despite the fact that it is legal, it is not profitable. Because of bug described at
https://github.com/llvm/llvm-project/issues/60234, now the guard widening is
only possible when condtion we want to add is available at the point of the
widenable_condition() of dominating guard. It means that, if all such calls are
hoisted out of loop, and the loop conditions depend on loop-variants, we cannot
widen. Hoisting is otherwise not helpful, because it does not introduce any
optimization opportunities.


https://reviews.llvm.org/D146274

Files:
  llvm/lib/Transforms/Scalar/LICM.cpp
  llvm/test/Transforms/GuardWidening/two_forms_behavior_consistency.ll
  llvm/test/Transforms/LICM/explicit_guards.ll

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