diff options
Diffstat (limited to 'lib/Analysis/ScalarEvolutionExpander.cpp')
| -rw-r--r-- | lib/Analysis/ScalarEvolutionExpander.cpp | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp index d110385fb3..507ced74fd 100644 --- a/lib/Analysis/ScalarEvolutionExpander.cpp +++ b/lib/Analysis/ScalarEvolutionExpander.cpp @@ -168,6 +168,8 @@ Value *SCEVExpander::expandAddToGEP(const SCEVAddExpr *S, std::vector<SCEVHandle> ScaledOps; for (unsigned i = 0, e = Ops.size(); i != e; ++i) { if (ElSize != 0) { + // For a Constant, check for a multiple of the pointer type's + // scale size. if (const SCEVConstant *C = dyn_cast<SCEVConstant>(Ops[i])) if (!C->getValue()->getValue().srem(ElSize)) { ConstantInt *CI = @@ -176,13 +178,19 @@ Value *SCEVExpander::expandAddToGEP(const SCEVAddExpr *S, ScaledOps.push_back(Div); continue; } + // In a Mul, check if there is a constant operand which is a multiple + // of the pointer type's scale size. if (const SCEVMulExpr *M = dyn_cast<SCEVMulExpr>(Ops[i])) if (const SCEVConstant *C = dyn_cast<SCEVConstant>(M->getOperand(0))) - if (C->getValue()->getValue() == ElSize) { - for (unsigned j = 1, f = M->getNumOperands(); j != f; ++j) - ScaledOps.push_back(M->getOperand(j)); + if (!C->getValue()->getValue().srem(ElSize)) { + std::vector<SCEVHandle> NewMulOps(M->getOperands()); + NewMulOps[0] = + SE.getConstant(C->getValue()->getValue().sdiv(ElSize)); + ScaledOps.push_back(SE.getMulExpr(NewMulOps)); continue; } + // In an Unknown, check if the underlying value is a Mul by a constant + // which is equal to the pointer type's scale size. if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(Ops[i])) if (BinaryOperator *BO = dyn_cast<BinaryOperator>(U->getValue())) if (BO->getOpcode() == Instruction::Mul) @@ -191,6 +199,8 @@ Value *SCEVExpander::expandAddToGEP(const SCEVAddExpr *S, ScaledOps.push_back(SE.getUnknown(BO->getOperand(0))); continue; } + // If the pointer type's scale size is 1, no scaling is necessary + // and any value can be used. if (ElSize == 1) { ScaledOps.push_back(Ops[i]); continue; |