[PATCH] D147662: [LoopPredication] Fix where we generate widened condition. PR61963

[Anna Thomas via Phabricator via llvm-commits]

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Loop predication's predicateLoopExit pass does two incorrect things:

It sinks the widenable call into the loop, thereby converting an invariant condition to a variant one
It widens the widenable call at a branch thereby converting it into a loop-varying one.

The latter is problematic when the branch may have been a loop-invariant
branch and prior optimizations (such as indvars) may have relied on this
fact, and updated the deopt state accordingly.

Now, when we widen this with a loop-varying condition, the deopt state
is no longer correct. See
https://github.com/llvm/llvm-project/issues/61963.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D147662

Files:
  llvm/lib/Transforms/Scalar/LoopPredication.cpp
  llvm/test/Transforms/LoopPredication/pr61963.ll

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