diff options
Diffstat (limited to 'lib/Transforms/Scalar/LoopStrengthReduce.cpp')
| -rw-r--r-- | lib/Transforms/Scalar/LoopStrengthReduce.cpp | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp index b83bec2..5847dfe 100644 --- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -2537,6 +2537,7 @@ void LSRInstance::ChainInstruction(Instruction *UserInst, Instruction *IVOper, // Add this IV user to the end of the chain. IVChainVec[ChainIdx].add(IVInc(UserInst, IVOper, LastIncExpr)); } + IVChain &Chain = IVChainVec[ChainIdx]; SmallPtrSet<Instruction*,4> &NearUsers = ChainUsersVec[ChainIdx].NearUsers; // This chain's NearUsers become FarUsers. @@ -2554,8 +2555,19 @@ void LSRInstance::ChainInstruction(Instruction *UserInst, Instruction *IVOper, for (Value::use_iterator UseIter = IVOper->use_begin(), UseEnd = IVOper->use_end(); UseIter != UseEnd; ++UseIter) { Instruction *OtherUse = dyn_cast<Instruction>(*UseIter); - if (!OtherUse || OtherUse == UserInst) + if (!OtherUse) continue; + // Uses in the chain will no longer be uses if the chain is formed. + // Include the head of the chain in this iteration (not Chain.begin()). + IVChain::const_iterator IncIter = Chain.Incs.begin(); + IVChain::const_iterator IncEnd = Chain.Incs.end(); + for( ; IncIter != IncEnd; ++IncIter) { + if (IncIter->UserInst == OtherUse) + break; + } + if (IncIter != IncEnd) + continue; + if (SE.isSCEVable(OtherUse->getType()) && !isa<SCEVUnknown>(SE.getSCEV(OtherUse)) && IU.isIVUserOrOperand(OtherUse)) { |