class ValidatorResult visitAddRecExpr(const SCEVAddRecExpr *Expr) {
if (!Expr->isAffine()) {
DEBUG(dbgs() << "INVALID: AddRec is not affine");
return ValidatorResult(SCEVType::INVALID);
}
ValidatorResult Start = visit(Expr->getStart());
ValidatorResult Recurrence = visit(Expr->getStepRecurrence(SE));
if (!Start.isValid())
return Start;
if (!Recurrence.isValid())
return Recurrence;
auto *L = Expr->getLoop();
if (R->contains(L) && (!Scope || !L->contains(Scope))) {
DEBUG(dbgs() << "INVALID: AddRec out of a loop whose exit value is not "
"synthesizable");
return ValidatorResult(SCEVType::INVALID);
}
if (R->contains(L)) {
if (Recurrence.isINT()) {
ValidatorResult Result(SCEVType::IV);
Result.addParamsFrom(Start);
return Result;
}
DEBUG(dbgs() << "INVALID: AddRec within scop has non-int"
"recurrence part");
return ValidatorResult(SCEVType::INVALID);
}
assert(Start.isConstant() && Recurrence.isConstant() &&
"Expected 'Start' and 'Recurrence' to be constant");
// Directly generate ValidatorResult for Expr if 'start' is zero.
if (Expr->getStart()->isZero())
return ValidatorResult(SCEVType::PARAM, Expr);
// Translate AddRecExpr from '{start, +, inc}' into 'start + {0, +, inc}'
// if 'start' is not zero.
const SCEV *ZeroStartExpr = SE.getAddRecExpr(
SE.getConstant(Expr->getStart()->getType(), 0),
Expr->getStepRecurrence(SE), Expr->getLoop(), Expr->getNoWrapFlags());
ValidatorResult ZeroStartResult =
ValidatorResult(SCEVType::PARAM, ZeroStartExpr);
ZeroStartResult.addParamsFrom(Start);
return ZeroStartResult;
}
