[llvm] [VPlan] Connect (MemRuntime|SCEV)Check blocks as VPlan transform (NFC). (PR #143879)

[via llvm-commits]

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@@ -548,6 +552,9 @@ class LoopVectorizationPlanner {
                                   VPRecipeBuilder &RecipeBuilder,
                                   ElementCount MinVF);
 
+  /// Add the runtime checks from \p RTChecks to \p VPlan.
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ayalz wrote:

If refraining from adjusting the position is only to avoid test changes, worth indicating in a TODO.

But keeping the IRBB's detached is a design decision - to keep the original IR intact, until VPlan execution, which starts with SCEV expansions in the original header block.

https://github.com/llvm/llvm-project/pull/143879