Value *Cond = BI->getCondition();
FCmpInst *FCmp = dyn_cast<FCmpInst>(Cond);
- if (!FCmp || !FCmp->isEquality())
+ if (!FCmp)
return false;
+ bool isProb;
+ if (FCmp->isEquality()) {
+ // f1 == f2 -> Unlikely
+ // f1 != f2 -> Likely
+ isProb = !FCmp->isTrueWhenEqual();
+ } else if (FCmp->getPredicate() == FCmpInst::FCMP_ORD) {
+ // !isnan -> Likely
+ isProb = true;
+ } else if (FCmp->getPredicate() == FCmpInst::FCMP_UNO) {
+ // isnan -> Unlikely
+ isProb = false;
+ } else {
+ return false;
+ }
+
BasicBlock *Taken = BI->getSuccessor(0);
BasicBlock *NonTaken = BI->getSuccessor(1);
- // f1 == f2 -> Unlikely
- // f1 != f2 -> Likely
- if (FCmp->isTrueWhenEqual())
+ if (!isProb)
std::swap(Taken, NonTaken);
BP->setEdgeWeight(BB, Taken, FPH_TAKEN_WEIGHT);