diff options
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineCalls.cpp | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp index fc62bb0cf8..0d5e30205a 100644 --- a/lib/Transforms/InstCombine/InstCombineCalls.cpp +++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp @@ -96,12 +96,17 @@ static unsigned EnforceKnownAlignment(Value *V, /// increase the alignment of the ultimate object, making this check succeed. unsigned InstCombiner::GetOrEnforceKnownAlignment(Value *V, unsigned PrefAlign) { - unsigned BitWidth = TD ? TD->getTypeSizeInBits(V->getType()) : - sizeof(PrefAlign) * CHAR_BIT; + assert(V->getType()->isPointerTy() && + "GetOrEnforceKnownAlignment expects a pointer!"); + unsigned BitWidth = TD ? TD->getPointerSizeInBits() : 64; APInt Mask = APInt::getAllOnesValue(BitWidth); APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0); ComputeMaskedBits(V, Mask, KnownZero, KnownOne); unsigned TrailZ = KnownZero.countTrailingOnes(); + + // LLVM doesn't support alignments larger than this currently. + TrailZ = std::min(TrailZ, unsigned(sizeof(unsigned) * CHAR_BIT - 1)); + unsigned Align = 1u << std::min(BitWidth - 1, TrailZ); if (PrefAlign > Align) |