[llvm] [VPlan] Hook IR blocks into VPlan during skeleton creation (NFC) (PR #114292)

[via llvm-commits]

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@@ -3762,36 +3757,27 @@ class VPlan {
   DenseMap<const SCEV *, VPValue *> SCEVToExpansion;
 
 public:
-  /// Construct a VPlan with original preheader \p Preheader, trip count \p TC,
-  /// \p Entry to the plan and with \p ScalarHeader wrapping the original header
-  /// of the scalar loop. At the moment, \p Preheader and \p Entry need to be
-  /// disconnected, as the bypass blocks between them are not yet modeled in
-  /// VPlan.
-  VPlan(VPBasicBlock *Preheader, VPValue *TC, VPBasicBlock *Entry,
-        VPIRBasicBlock *ScalarHeader)
-      : VPlan(Preheader, Entry, ScalarHeader) {
+  /// Construct a VPlan with \p Entry entering the plan and trip count \p TC.
+  VPlan(VPBasicBlock *Entry, VPValue *TC, VPIRBasicBlock *ScalarHeader)
+      : VPlan(Entry, ScalarHeader) {
     TripCount = TC;
   }
 
-  /// Construct a VPlan with original preheader \p Preheader, \p Entry to
-  /// the plan and with \p ScalarHeader wrapping the original header of the
-  /// scalar loop. At the moment, \p Preheader and \p Entry need to be
-  /// disconnected, as the bypass blocks between them are not yet modeled in
-  /// VPlan.
-  VPlan(VPBasicBlock *Preheader, VPBasicBlock *Entry,
-        VPIRBasicBlock *ScalarHeader)
-      : Entry(Entry), Preheader(Preheader), ScalarHeader(ScalarHeader) {
+  /// Construct a VPlan with \p Entry to the plan.
----------------
ayalz wrote:

```suggestion
  /// Construct a VPlan with \p Entry to the plan and with \p ScalarHeader wrapping the original header of the scalar loop.
```

https://github.com/llvm/llvm-project/pull/114292