llvm-project

2c165055 - [OpenMP][offload] Fix single-thread SPMD cross-team reductions (#231843)

[OpenMP][offload] Fix single-thread SPMD cross-team reductions (#231843) If a kernel gets SPMDized by OpenMPOpt but does not have a parallel region, it actually is only executed by a single thread. forceSingleThreadPerWorkgroupHelper() is responsible for that and had been introduced by https://reviews.llvm.org/D133120. The cross-team reduction trusted that SPMD mode means that we can re-use the threads of the parallel region. Now, OpenMPOpt explicitly limits affected kernels to a single thread per team via the kernel environment, so that we actually know how many threads we have available. This also changes omp_get_thread_limit(). Claude assisted with this patch.