diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/ConstantHoisting.cpp | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp b/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp index 55759e8b166..694edbc87a7 100644 --- a/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp +++ b/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp @@ -585,10 +585,30 @@ void ConstantHoistingPass::findBaseConstants() { for (auto CC = std::next(ConstCandVec.begin()), E = ConstCandVec.end(); CC != E; ++CC) { if (MinValItr->ConstInt->getType() == CC->ConstInt->getType()) { + Type *MemUseValTy = nullptr; + for (auto &U : CC->Uses) { + auto *UI = U.Inst; + if (LoadInst *LI = dyn_cast<LoadInst>(UI)) { + MemUseValTy = LI->getType(); + break; + } else if (StoreInst *SI = dyn_cast<StoreInst>(UI)) { + // Make sure the constant is used as pointer operand of the StoreInst. + if (SI->getPointerOperand() == SI->getOperand(U.OpndIdx)) { + MemUseValTy = SI->getValueOperand()->getType(); + break; + } + } + } + // Check if the constant is in range of an add with immediate. APInt Diff = CC->ConstInt->getValue() - MinValItr->ConstInt->getValue(); if ((Diff.getBitWidth() <= 64) && - TTI->isLegalAddImmediate(Diff.getSExtValue())) + TTI->isLegalAddImmediate(Diff.getSExtValue()) && + // Check if Diff can be used as offset in addressing mode of the user + // memory instruction. + (!MemUseValTy || TTI->isLegalAddressingMode(MemUseValTy, + /*BaseGV*/nullptr, /*BaseOffset*/Diff.getSExtValue(), + /*HasBaseReg*/true, /*Scale*/0))) continue; } // We either have now a different constant type or the constant is not in |
