diff options
Diffstat (limited to 'lib/Transforms/Scalar')
| -rw-r--r-- | lib/Transforms/Scalar/IndVarSimplify.cpp | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp index 7785855..cfd8db0 100644 --- a/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -1479,8 +1479,14 @@ static Value *genLoopLimit(PHINode *IndVar, const SCEV *IVCount, Loop *L, if (IndVar->getType()->isPointerTy() && !IVCount->getType()->isPointerTy()) { + // IVOffset will be the new GEP offset that is interpreted by GEP as a + // signed value. IVCount on the other hand represents the loop trip count, + // which is an unsigned value. FindLoopCounter only allows induction + // variables that have a positive unit stride of one. This means we don't + // have to handle the case of negative offsets (yet) and just need to zero + // extend IVCount. Type *OfsTy = SE->getEffectiveSCEVType(IVInit->getType()); - const SCEV *IVOffset = SE->getTruncateOrSignExtend(IVCount, OfsTy); + const SCEV *IVOffset = SE->getTruncateOrZeroExtend(IVCount, OfsTy); // Expand the code for the iteration count. assert(SE->isLoopInvariant(IVOffset, L) && |