[Mlir-commits] [mlir] [MLIR][NFC] Speed up is valid symbol check (PR #154924)

[Mehdi Amini]

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@@ -427,6 +427,25 @@ bool mlir::affine::isValidSymbol(Value value) {
   return false;
 }
 
+/// A utility function to check if a value is defined at the top level of
+/// `region` or is an argument of `region` or dominates the region.
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joker-eph wrote:

> the underlying code checks the is isolated from above constraint, areValuesDefinedAbove isn't equivalent

Seems like `areValuesDefinedAbove` should be updated instead: I don't think we should have the same utility with a different implementation multiple-times in the codebase.

That said: checking for traits may very well be more expensive than getting all the parent regions.

https://github.com/llvm/llvm-project/pull/154924