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

[via llvm-commits]

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@@ -22,6 +22,7 @@ add_llvm_component_library(LLVMVectorize
   VectorCombine.cpp
   VPlan.cpp
   VPlanAnalysis.cpp
+  VPlanConstruction.cpp
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ayalz wrote:

Ok, let's go with VPlanConstruction.cpp for now, which expresses what it's about rather than how (may or may not involve VPlanTransforms).

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