/// operations. This allows them to be analyzed by regular SCEV code.
///
const SCEV *ScalarEvolution::createNodeForGEP(GEPOperator *GEP) {
+ Type *IntPtrTy = getEffectiveSCEVType(GEP->getType());
+ Value *Base = GEP->getOperand(0);
+ // Don't attempt to analyze GEPs over unsized objects.
+ if (!cast<PointerType>(Base->getType())->getElementType()->isSized())
+ return getUnknown(GEP);
// Don't blindly transfer the inbounds flag from the GEP instruction to the
// Add expression, because the Instruction may be guarded by control flow
// and the no-overflow bits may not be valid for the expression in any
// context.
- bool isInBounds = GEP->isInBounds();
+ SCEV::NoWrapFlags Wrap = GEP->isInBounds() ? SCEV::FlagNSW : SCEV::FlagAnyWrap;
- Type *IntPtrTy = getEffectiveSCEVType(GEP->getType());
- Value *Base = GEP->getOperand(0);
- // Don't attempt to analyze GEPs over unsized objects.
- if (!cast<PointerType>(Base->getType())->getElementType()->isSized())
- return getUnknown(GEP);
const SCEV *TotalOffset = getConstant(IntPtrTy, 0);
gep_type_iterator GTI = gep_type_begin(GEP);
for (GetElementPtrInst::op_iterator I = llvm::next(GEP->op_begin()),
IndexS = getTruncateOrSignExtend(IndexS, IntPtrTy);
// Multiply the index by the element size to compute the element offset.
- const SCEV *LocalOffset = getMulExpr(IndexS, ElementSize,
- isInBounds ? SCEV::FlagNSW :
- SCEV::FlagAnyWrap);
+ const SCEV *LocalOffset = getMulExpr(IndexS, ElementSize, Wrap);
// Add the element offset to the running total offset.
TotalOffset = getAddExpr(TotalOffset, LocalOffset);
const SCEV *BaseS = getSCEV(Base);
// Add the total offset from all the GEP indices to the base.
- return getAddExpr(BaseS, TotalOffset,
- isInBounds ? SCEV::FlagNSW : SCEV::FlagAnyWrap);
+ return getAddExpr(BaseS, TotalOffset, Wrap);
}
/// GetMinTrailingZeros - Determine the minimum number of zero bits that S is