std::pair<BasicBlock *, Value *>
EpilogueVectorizerMainLoop::createEpilogueVectorizedLoopSkeleton() {
MDNode *OrigLoopID = OrigLoop->getLoopID();
+
+ // Workaround! Compute the trip count of the original loop and cache it
+ // before we start modifying the CFG. This code has a systemic problem
+ // wherein it tries to run analysis over partially constructed IR; this is
+ // wrong, and not simply for SCEV. The trip count of the original loop
+ // simply happens to be prone to hitting this in practice. In theory, we
+ // can hit the same issue for any SCEV, or ValueTracking query done during
+ // mutation. See PR49900.
+ getOrCreateTripCount(OrigLoop->getLoopPreheader());
Loop *Lp = createVectorLoopSkeleton("");
// Generate the code to check the minimum iteration count of the vector