[llvm] [LoopUnroll] Add UnrollMultiExit to loop unrolling options (NFC) (PR #124462)

[Nikita Popov via llvm-commits]

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@@ -622,6 +622,9 @@ class TargetTransformInfo {
     /// Don't allow runtime unrolling if expanding the trip count takes more
     /// than SCEVExpansionBudget.
     unsigned SCEVExpansionBudget;
+    /// Allow runtime unrolling multi-exit loops. Should only be set if the
+    /// target determined that multi-exit unrolling is profitable for the loop.
+    bool UnrollMultiExit;
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nikic wrote:

```suggestion
    bool RuntimeUnrollMultiExit;
```
To clarify that this affects only runtime unrolling?

https://github.com/llvm/llvm-project/pull/124462