[PATCH] D32605: Recognize CTLZ builtin

[Evgeny Stupachenko via Phabricator via llvm-commits]

evstupac added inline comments.


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Comment at: llvm/trunk/lib/Transforms/Scalar/LoopIdiomRecognize.cpp:1296
+  // check in CTLZ intrinsic.
+  if (BasicBlock *PreCondBB = PH->getSinglePredecessor())
+    if (BranchInst *PreCondBr =
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Just made a follow up commit r303212 adding "!IsCntPhiUsedOutsideLoop" check here.
Previously the code was potentially buggy because in case IsCntPhiUsedOutsideLoop we inserted CTLZ(X >> 1) and rely on check X != 0 (instead of (X >> 1) != 0).


Repository:
  rL LLVM

https://reviews.llvm.org/D32605