From ec7029c286c6a8e49db52c752d87c9ff0a465996 Mon Sep 17 00:00:00 2001 From: Serguei Katkov Date: Mon, 5 Feb 2018 05:49:47 +0000 Subject: Re-apply [SCEV] Fix isLoopEntryGuardedByCond usage ScalarEvolution::isKnownPredicate invokes isLoopEntryGuardedByCond without check that SCEV is available at entry point of the loop. It is incorrect and fixed by patch. To bugs additionally fixed: assert is moved after the check whether loop is not a nullptr. Usage of isLoopEntryGuardedByCond in ScalarEvolution::isImpliedCondOperandsViaNoOverflow is guarded by isAvailableAtLoopEntry. Reviewers: sanjoy, mkazantsev, anna, dorit, reames Reviewed By: mkazantsev Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D42417 llvm-svn: 324204 --- .../Scalar/InductiveRangeCheckElimination.cpp | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'llvm/lib/Transforms') diff --git a/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp b/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp index 6a63476fcc3..11ad4275f78 100644 --- a/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp +++ b/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp @@ -934,9 +934,9 @@ LoopStructure::parseLoopStructure(ScalarEvolution &SE, return None; } - if (!SE.isLoopEntryGuardedByCond( - &L, BoundPred, IndVarStart, - SE.getAddExpr(RightSCEV, Step))) { + if (!SE.isAvailableAtLoopEntry(RightSCEV, &L) || + !SE.isLoopEntryGuardedByCond(&L, BoundPred, IndVarStart, + SE.getAddExpr(RightSCEV, Step))) { FailureReason = "Induction variable start not bounded by upper limit"; return None; } @@ -948,7 +948,8 @@ LoopStructure::parseLoopStructure(ScalarEvolution &SE, RightValue = B.CreateAdd(RightValue, One); } } else { - if (!SE.isLoopEntryGuardedByCond(&L, BoundPred, IndVarStart, RightSCEV)) { + if (!SE.isAvailableAtLoopEntry(RightSCEV, &L) || + !SE.isLoopEntryGuardedByCond(&L, BoundPred, IndVarStart, RightSCEV)) { FailureReason = "Induction variable start not bounded by upper limit"; return None; } @@ -1014,9 +1015,10 @@ LoopStructure::parseLoopStructure(ScalarEvolution &SE, return None; } - if (!SE.isLoopEntryGuardedByCond( - &L, BoundPred, IndVarStart, - SE.getMinusSCEV(RightSCEV, SE.getOne(RightSCEV->getType())))) { + if (!SE.isAvailableAtLoopEntry(RightSCEV, &L) || + !SE.isLoopEntryGuardedByCond( + &L, BoundPred, IndVarStart, + SE.getMinusSCEV(RightSCEV, SE.getOne(RightSCEV->getType())))) { FailureReason = "Induction variable start not bounded by lower limit"; return None; } @@ -1028,7 +1030,8 @@ LoopStructure::parseLoopStructure(ScalarEvolution &SE, RightValue = B.CreateSub(RightValue, One); } } else { - if (!SE.isLoopEntryGuardedByCond(&L, BoundPred, IndVarStart, RightSCEV)) { + if (!SE.isAvailableAtLoopEntry(RightSCEV, &L) || + !SE.isLoopEntryGuardedByCond(&L, BoundPred, IndVarStart, RightSCEV)) { FailureReason = "Induction variable start not bounded by lower limit"; return None; } -- cgit v1.2.3