+static bool IsIncrementNSW(ScalarEvolution &SE, const SCEVAddRecExpr *AR) {
+ if (!isa<IntegerType>(AR->getType()))
+ return false;
+
+ unsigned BitWidth = cast<IntegerType>(AR->getType())->getBitWidth();
+ Type *WideTy = IntegerType::get(AR->getType()->getContext(), BitWidth * 2);
+ const SCEV *Step = AR->getStepRecurrence(SE);
+ const SCEV *OpAfterExtend = SE.getAddExpr(SE.getSignExtendExpr(Step, WideTy),
+ SE.getSignExtendExpr(AR, WideTy));
+ const SCEV *ExtendAfterOp =
+ SE.getSignExtendExpr(SE.getAddExpr(AR, Step), WideTy);
+ return ExtendAfterOp == OpAfterExtend;
+}
+
+static bool IsIncrementNUW(ScalarEvolution &SE, const SCEVAddRecExpr *AR) {
+ if (!isa<IntegerType>(AR->getType()))
+ return false;
+
+ unsigned BitWidth = cast<IntegerType>(AR->getType())->getBitWidth();
+ Type *WideTy = IntegerType::get(AR->getType()->getContext(), BitWidth * 2);
+ const SCEV *Step = AR->getStepRecurrence(SE);
+ const SCEV *OpAfterExtend = SE.getAddExpr(SE.getZeroExtendExpr(Step, WideTy),
+ SE.getZeroExtendExpr(AR, WideTy));
+ const SCEV *ExtendAfterOp =
+ SE.getZeroExtendExpr(SE.getAddExpr(AR, Step), WideTy);
+ return ExtendAfterOp == OpAfterExtend;
+}
+