/// BackedgeTakenInfo. If these expressions have not been reduced, then
/// expanding them may incur additional cost (albeit in the loop preheader).
static bool isHighCostExpansion(const SCEV *S, BranchInst *BI,
+ SmallPtrSet<const SCEV*, 8> &Processed,
ScalarEvolution *SE) {
+ if (!Processed.insert(S))
+ return false;
+
// If the backedge-taken count is a UDiv, it's very likely a UDiv that
// ScalarEvolution's HowFarToZero or HowManyLessThans produced to compute a
// precise expression, rather than a UDiv from the user's code. If we can't
if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(S)) {
for (SCEVAddExpr::op_iterator I = Add->op_begin(), E = Add->op_end();
I != E; ++I) {
- if (isHighCostExpansion(*I, BI, SE))
+ if (isHighCostExpansion(*I, BI, Processed, SE))
return true;
}
return false;
if (!BI)
return false;
- if (isHighCostExpansion(BackedgeTakenCount, BI, SE))
+ SmallPtrSet<const SCEV*, 8> Processed;
+ if (isHighCostExpansion(BackedgeTakenCount, BI, Processed, SE))
return false;
return true;