From 6a1dd77f5daac189954be962a853719e291f5f1f Mon Sep 17 00:00:00 2001 From: Anna Thomas Date: Tue, 14 Aug 2018 20:25:13 +0000 Subject: NFC: Clarify comment in loop vectorization legality Clarifying the comment about PSCEV and external IV users by referencing the bug in question. llvm-svn: 339722 --- llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp') diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp index 97a61bd0d78..49f8658ef45 100644 --- a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp +++ b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp @@ -563,7 +563,8 @@ void LoopVectorizationLegality::addInductionPhi( // back into the PHI node may have external users. // We can allow those uses, except if the SCEVs we have for them rely // on predicates that only hold within the loop, since allowing the exit - // currently means re-using this SCEV outside the loop. + // currently means re-using this SCEV outside the loop (see PR33706 for more + // details). if (PSE.getUnionPredicate().isAlwaysTrue()) { AllowedExit.insert(Phi); AllowedExit.insert(Phi->getIncomingValueForBlock(TheLoop->getLoopLatch())); -- cgit v1.2.3