[llvm] [VPlan] Refactor VPlan creation, add transform introducing region (NFC). (PR #128419)

[Florian Hahn via llvm-commits]

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@@ -32,6 +32,82 @@
 
 using namespace llvm;
 
+void VPlanTransforms::introduceTopLevelVectorLoopRegion(
+    VPlan &Plan, Type *InductionTy, PredicatedScalarEvolution &PSE,
+    bool RequiresScalarEpilogueCheck, bool TailFolded, Loop *TheLoop) {
+  auto *HeaderVPBB = cast<VPBasicBlock>(Plan.getEntry()->getSingleSuccessor());
+  VPBlockUtils::disconnectBlocks(Plan.getEntry(), HeaderVPBB);
+
+  VPBasicBlock *OriginalLatch =
+      cast<VPBasicBlock>(HeaderVPBB->getSinglePredecessor());
+  VPBlockUtils::disconnectBlocks(OriginalLatch, HeaderVPBB);
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fhahn wrote:

Doje, thanks

https://github.com/llvm/llvm-project/pull/128419