On 9/16/20 1:24 PM, Alexander Monakov wrote: > Can you supply a tar with tree dumps for me to look at please? >
Hi Alexander, https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95654#c6 . > Also, if you can check if the problem can be triggered without a > collapsed loop (e.g. try removing collapse(2), remove mentions of > d2) and if so supply dumps from that instead, I'd appreciate that too. > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95654#c8 Thanks, - Tom > Alexander > > On Wed, 16 Sep 2020, Tom de Vries wrote: > >> [ cc-ing author omp support for nvptx. ] >> >> On 9/16/20 12:39 PM, Tobias Burnus wrote: >>> Hi Tom, hi Richard, hello all, >>> >>> @Richard: does it look okay from the ME side? >>> @Tom: Can you check which IFN_GOMP_SIMT should be >>> excluded with -ftracer? >>> >>> Pre-remark, I do not know much about SIMT – except that they >>> only appear with nvptx and somehow relate to lanes on the >>> GPU. >>> >>> In any case, as the testcase libgomp.fortran/pr66199-5.f90 shows, >>> if a basic block with GOMP_SIMT_VOTE_ANY in it is duplicated, >>> which happens via -ftracer for this testcase, the result is wrong. >>> >>> The testcase ignores all the loop work but via "lastprivate" takes >>> the upper loop bound (as assigned to the loop indices); instead of >>> the expected 32*32 = 1024, either some number (like 4 or very large >>> or negative) is returned. >>> >>> While GOMP_SIMT_VOTE_ANY fixes the issue for this testcase, I >>> have the feeling that at least GOMP_SIMT_LAST_LANE should be >>> not copied - but I might be wrong. >>> >>> Tom: Do you think GOMP_SIMT_LAST_LANE should be removed from >>> that list – or any of the following added as well? >>> GOMP_USE_SIMT, GOMP_SIMT_ENTER, GOMP_SIMT_ENTER_ALLOC, GOMP_SIMT_EXIT, >>> GOMP_SIMT_VF, GOMP_SIMT_ORDERED_PRED, GOMP_SIMT_XCHG_BFLY, >>> GOMP_SIMT_XCHG_IDX >>> >>> OK for mainline? >>> >>> Tobias >>> >>> ----------------- >>> Mentor Graphics (Deutschland) GmbH, Arnulfstraße 201, 80634 München / >>> Germany >>> Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, >>> Alexander Walter
