[flang-commits] [flang] [flang] Reclassify MVBITS, SPLIT, and TOKENIZE as SIMPLE (PR #205024)

[Caroline Newcombe via flang-commits]

cenewcombe wrote:

I'll review this PR soon and I've requested @eugeneepshteyn's review as well. I'm hoping to pick up work on `SIMPLE` from here — completing the semantic constraints and then propagating the attribute to FIR so `SIMPLE` calls with loop-invariant arguments can be hoisted out of loops.

This PR covers intrinsic subroutines; I plan to follow up with a similar patch for intrinsic functions, unless you're already working on it. Either is a prerequisite for the semantics work: once the requirement for a SIMPLE procedure to only reference `SIMPLE` procedures is enforced, intrinsics need to be classified correctly or valid code like `abs()` inside a `SIMPLE` procedure would fail.

@mlir-maiden, do you have any further work in progress or planned for SIMPLE? If so, we can coordinate. Either way, I'd like to review this PR and see it land. Thanks for your work on this!

https://github.com/llvm/llvm-project/pull/205024