[llvm] [LV] Transform to handle exits in the scalar loop (PR #148626)

[Graham Hunter via llvm-commits]

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@@ -4224,12 +4232,17 @@ class VPlan {
   /// Returns the preheader of the vector loop region, if one exists, or null
   /// otherwise.
   VPBasicBlock *getVectorPreheader() {
+    if (EarlyExitPreheader)
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huntergr-arm wrote:

The problem I faced was check blocks being generated out of order, even though they appeared correct in the printed vplan. So I've forced it this way to get things working; I'll look for something better.

https://github.com/llvm/llvm-project/pull/148626