[llvm] Expanding the Histogram Intrinsic (PR #127399)

[Laine Taffin Altman via llvm-commits]

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@@ -1079,34 +1079,41 @@ bool LoopVectorizationLegality::canVectorizeInstrs() {
 
 /// Find histogram operations that match high-level code in loops:
 /// \code
-/// buckets[indices[i]]+=step;
+/// buckets[indices[i]] = UpdateOpeartor(buckets[indices[i]], Val);
 /// \endcode
+/// When updateOperator can be add, sub, add.sat, umin, umax, sub.
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pthariensflame wrote:

```suggestion
/// When updateOperator can be add, sub, add.sat, umin, umax.
```

https://github.com/llvm/llvm-project/pull/127399