[llvm] [VPlan] Dispatch to multiple exit blocks via middle blocks. (PR #112138)

[Florian Hahn via llvm-commits]

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@@ -3831,12 +3832,16 @@ class VPlan {
   /// whether to execute the scalar tail loop or the exit block from the loop
   /// latch.
   const VPBasicBlock *getMiddleBlock() const {
-    return cast<VPBasicBlock>(getVectorLoopRegion()->getSingleSuccessor());
+    return cast<VPBasicBlock>(getScalarPreheader()->getSinglePredecessor());
   }
   VPBasicBlock *getMiddleBlock() {
-    return cast<VPBasicBlock>(getVectorLoopRegion()->getSingleSuccessor());
+    return cast<VPBasicBlock>(getScalarPreheader()->getSinglePredecessor());
   }
 
+  /// Return the exit blocks of the VPlan, that is leaf nodes except the scalar
+  /// header.
+  auto getExitBlocks();
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fhahn wrote:

(should be resolved after landing https://github.com/llvm/llvm-project/pull/115066)

https://github.com/llvm/llvm-project/pull/112138