[Mlir-commits] [mlir] [WIP][OpenMP][MLIR] Lowering task_reduction clause for pass-by-value vars to LLVMIR (PR #125218)

[llvmlistbot at llvm.org]

NimishMishra wrote:

Hi @tblah ,

I was working on refactoring pass-by-val vars from https://github.com/llvm/llvm-project/pull/120957, and had a few points where I was wondering if you could suggest:

1. Is it better if this functionality is offloaded to the OMPIRBuilder, or is the current setup okay?

2. You mentioned that https://github.com/llvm/llvm-project/pull/120957 assumes that all SSA values passed into the reduction are stack allocated, which is not always true (lines 1965 to 1973 in OpenMPToLLVMIRTranslation.cpp in that PR). Could you point me to a relevant PR or some similar functionality which can help me resolve this issue? I'm a bit clueless about this.

3. This version of the LLVMIR translation emits "empty" function bodies for init and combiner (instead of nullptr as https://github.com/llvm/llvm-project/pull/120957 was doing) in case we encounter an empty region for these functions. For finalization is optional, so a nullptr is emitted. Hope this is okay. Or should we throw an assertion here?

I have a few other comments from Kareem too; will incorporate those as well and make this PR ready for review thereafter.

https://github.com/llvm/llvm-project/pull/125218