[llvm] [VPlan] Move initial skeleton construction earlier (NFC). (PR #150848)

[Florian Hahn via llvm-commits]

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@@ -54,21 +54,27 @@ struct VPlanTransforms {
       verifyVPlanIsValid(Plan);
   }
 
-  LLVM_ABI_FOR_TEST static std::unique_ptr<VPlan> buildPlainCFG(Loop *TheLoop,
-                                                                LoopInfo &LI);
-
-  /// Prepare the plan for vectorization. It will introduce a dedicated
-  /// VPBasicBlock for the vector pre-header as well as a VPBasicBlock as exit
-  /// block of the main vector loop (middle.block). If a check is needed to
+  /// Create a base VPlan0, serving as the common starting point for all later
+  /// candidates. It consists of an initial plain CFG loop with loop blocks from
+  /// \p TheLoop being directly translated to VPBasicBlocks with VPInstruction
+  /// corresponding to the input IR.
+  ///
+  /// The created loop is wrapped into an initial skeleton to facilitate
+  /// vectorization, consisting of a vector pre-header, a exit block for the
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fhahn wrote:

done thanks

https://github.com/llvm/llvm-project/pull/150848