[Mlir-commits] [mlir] [SCF] add debug label for MergeNestedParallelLoops pattern (PR #135980)

[Ivan Butygin]

Hardcode84 wrote:

> > I don't think this particular pattern is very good candidate for canonicalization a
> 
> That I could agree with: parallelism is often expressed in a hierarchical way for good reasons, the collapsing done here is losing this information and does not seem like a good canonicalization to me.

`scf.parallel` already support arbitrarily nested loops as part of the op itself and loop order is preserved by this pattern (but `scf.parallel` doesn't assign any particular semantics to the loop order). So I don't think any info is actually lost within upstream `scf.parallel` semantics.

https://github.com/llvm/llvm-project/pull/135980