[PATCH] D107766: [InstCombine] Get rid of `hasOneUses()` when swapping `lshr` and `zext`

[Anton Afanasyev via Phabricator via llvm-commits]

anton-afanasyev created this revision.
anton-afanasyev added reviewers: RKSimon, spatel, ABataev, dtemirbulatov.
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Get rid of redundant `hasOneUse()` check while combining `lshr` and `zext`.
Transformation `lshr (zext iM X to iN), C --> zext (lshr X, C) to iN`
may be executed when original `zext` is used multiple times if it is
not eliminated.

Fixes first part of PR50555.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D107766

Files:
  llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
  llvm/test/Transforms/InstCombine/2008-01-21-MulTrunc.ll
  llvm/test/Transforms/InstCombine/apint-cast.ll
  llvm/test/Transforms/InstCombine/cast.ll
  llvm/test/Transforms/InstCombine/pr50555.ll
  llvm/test/Transforms/SLPVectorizer/X86/pr50555.ll

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