1/* Copyright (C) 2005-2015 Free Software Foundation, Inc. 2 Contributed by Richard Henderson <rth@redhat.com>. 3 4 This file is part of the GNU Offloading and Multi Processing Library 5 (libgomp). 6 7 Libgomp is free software; you can redistribute it and/or modify it 8 under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 14 FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15 more details. 16 17 Under Section 7 of GPL version 3, you are granted additional 18 permissions described in the GCC Runtime Library Exception, version 19 3.1, as published by the Free Software Foundation. 20 21 You should have received a copy of the GNU General Public License and 22 a copy of the GCC Runtime Library Exception along with this program; 23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 <http://www.gnu.org/licenses/>. */ 25 26/* This file handles the SINGLE construct. */ 27 28#include "libgomp.h" 29 30 31/* This routine is called when first encountering a SINGLE construct that 32 doesn't have a COPYPRIVATE clause. Returns true if this is the thread 33 that should execute the clause. */ 34 35bool 36GOMP_single_start (void) 37{ 38#ifdef HAVE_SYNC_BUILTINS 39 struct gomp_thread *thr = gomp_thread (); 40 struct gomp_team *team = thr->ts.team; 41 unsigned long single_count; 42 43 if (__builtin_expect (team == NULL, 0)) 44 return true; 45 46 single_count = thr->ts.single_count++; 47 return __sync_bool_compare_and_swap (&team->single_count, single_count, 48 single_count + 1L); 49#else 50 bool ret = gomp_work_share_start (false); 51 if (ret) 52 gomp_work_share_init_done (); 53 gomp_work_share_end_nowait (); 54 return ret; 55#endif 56} 57 58/* This routine is called when first encountering a SINGLE construct that 59 does have a COPYPRIVATE clause. Returns NULL if this is the thread 60 that should execute the clause; otherwise the return value is pointer 61 given to GOMP_single_copy_end by the thread that did execute the clause. */ 62 63void * 64GOMP_single_copy_start (void) 65{ 66 struct gomp_thread *thr = gomp_thread (); 67 68 bool first; 69 void *ret; 70 71 first = gomp_work_share_start (false); 72 73 if (first) 74 { 75 gomp_work_share_init_done (); 76 ret = NULL; 77 } 78 else 79 { 80 gomp_team_barrier_wait (&thr->ts.team->barrier); 81 82 ret = thr->ts.work_share->copyprivate; 83 gomp_work_share_end_nowait (); 84 } 85 86 return ret; 87} 88 89/* This routine is called when the thread that entered a SINGLE construct 90 with a COPYPRIVATE clause gets to the end of the construct. */ 91 92void 93GOMP_single_copy_end (void *data) 94{ 95 struct gomp_thread *thr = gomp_thread (); 96 struct gomp_team *team = thr->ts.team; 97 98 if (team != NULL) 99 { 100 thr->ts.work_share->copyprivate = data; 101 gomp_team_barrier_wait (&team->barrier); 102 } 103 104 gomp_work_share_end_nowait (); 105} 106