From ca089b24d48ef6fa8da2d0bb8c25bb802c4a95c0 Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Thu, 13 Jul 2017 19:25:18 +0000 Subject: Vendor import of llvm trunk r307894: https://llvm.org/svn/llvm-project/llvm/trunk@307894 --- lib/Transforms/Vectorize/LoopVectorize.cpp | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'lib/Transforms/Vectorize/LoopVectorize.cpp') diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp index 193cc4d13787..eb82ee283d44 100644 --- a/lib/Transforms/Vectorize/LoopVectorize.cpp +++ b/lib/Transforms/Vectorize/LoopVectorize.cpp @@ -5315,8 +5315,13 @@ void LoopVectorizationLegality::addInductionPhi( // Both the PHI node itself, and the "post-increment" value feeding // back into the PHI node may have external users. - AllowedExit.insert(Phi); - AllowedExit.insert(Phi->getIncomingValueForBlock(TheLoop->getLoopLatch())); + // 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. + if (PSE.getUnionPredicate().isAlwaysTrue()) { + AllowedExit.insert(Phi); + AllowedExit.insert(Phi->getIncomingValueForBlock(TheLoop->getLoopLatch())); + } DEBUG(dbgs() << "LV: Found an induction variable.\n"); return; -- cgit v1.2.3