[llvm] [VPlan] Replace VPRegionBlock with explicit CFG before execute (NFCI). (PR #117506)

[via llvm-commits]

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@@ -462,6 +462,26 @@ Value *VPInstruction::generatePerLane(VPTransformState &State,
                               State.get(getOperand(1), Lane), Name);
 }
 
+/// Create a conditional branch using \p Cond branching to the successors of \p
+/// VPBB. Note that the first successor is always forward (i.e. not created yet)
+/// while the second successor may already have been created (if it is a header
+/// block and VPBB is a header).
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ayalz wrote:

```suggestion
/// block and VPBB is a latch).
```

https://github.com/llvm/llvm-project/pull/117506