[llvm] [VPlan] Endow DerivedIV with IRFlags (PR #205908)

[Florian Hahn via llvm-commits]

================
@@ -402,14 +402,13 @@ class VPBuilder {
     return RuntimeEC;
   }
 
-  /// Convert the input value \p Current to the corresponding value of an
-  /// induction with \p Start and \p Step values, using \p Start + \p Current *
-  /// \p Step.
+  /// Convert \p Index to \p Start + \p Index * \p Step.
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fhahn wrote:

may be good to keep the more generic, as index might imply induction, but I think it is also at least also used with trip counts

```suggestion
  /// Convert \p Current to \p Start + \p Index * \p Step.
```

https://github.com/llvm/llvm-project/pull/205908