[llvm] [VPlan] Remove loop region in optimizeForVFAndUF. (PR #108378)

[Alexey Bataev via llvm-commits]

================
@@ -7632,24 +7621,26 @@ DenseMap<const SCEV *, Value *> LoopVectorizationPlanner::executePlan(
       makeFollowupLoopID(OrigLoopID, {LLVMLoopVectorizeFollowupAll,
                                       LLVMLoopVectorizeFollowupVectorized});
 
-  VPBasicBlock *HeaderVPBB =
-      BestVPlan.getVectorLoopRegion()->getEntryBasicBlock();
-  Loop *L = LI->getLoopFor(State.CFG.VPBB2IRBB[HeaderVPBB]);
-  if (VectorizedLoopID)
-    L->setLoopID(*VectorizedLoopID);
-  else {
-    // Keep all loop hints from the original loop on the vector loop (we'll
-    // replace the vectorizer-specific hints below).
-    if (MDNode *LID = OrigLoop->getLoopID())
-      L->setLoopID(LID);
-
-    LoopVectorizeHints Hints(L, true, *ORE);
-    Hints.setAlreadyVectorized();
+  if (auto *R =
+          dyn_cast<VPRegionBlock>(BestVPlan.getEntry()->getSingleSuccessor())) {
+    VPBasicBlock *HeaderVPBB = R->getEntryBasicBlock();
+    Loop *L = LI->getLoopFor(State.CFG.VPBB2IRBB[HeaderVPBB]);
+    if (VectorizedLoopID)
+      L->setLoopID(*VectorizedLoopID);
+    else {
----------------
alexey-bataev wrote:

```suggestion
    if (VectorizedLoopID) {
      L->setLoopID(*VectorizedLoopID);
    } else {
```


https://github.com/llvm/llvm-project/pull/108378