projects / thirdparty / gcc.git / blame
| Commit | Line | Data |
|---|---|---|
| 83ffe9cd | 1 | /* Copyright (C) 2015-2023 Free Software Foundation, Inc. |
| fa499995 AS |
2 | Contributed by Mentor Embedded. |
| 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 is the AMD GCN implementation of doacross spinning. */ | |
| 27 | ||
| 28 | #ifndef GOMP_DOACROSS_H | |
| 29 | #define GOMP_DOACROSS_H 1 | |
| 30 | ||
| 31 | #include "libgomp.h" | |
| 32 | ||
| 33 | static inline int | |
| 34 | cpu_relax (void) | |
| 35 | { | |
| 36 | /* This can be implemented as just a memory barrier, but a sleep seems | |
| 37 | like it should allow the wavefront to yield (maybe?) | |
| 38 | Use the shortest possible sleep time of 1*64 cycles. */ | |
| 39 | asm volatile ("s_sleep\t1" ::: "memory"); | |
| 40 | return 0; | |
| 41 | } | |
| 42 | ||
| 43 | static inline void doacross_spin (unsigned long *addr, unsigned long expected, | |
| 44 | unsigned long cur) | |
| 45 | { | |
| 46 | /* Prevent compiler from optimizing based on bounds of containing object. */ | |
| 47 | asm ("" : "+r" (addr)); | |
| 48 | do | |
| 49 | { | |
| 50 | /* An alternative implementation might use s_setprio to lower the | |
| 51 | priority temporarily, and then restore it after. */ | |
| 52 | int i = cpu_relax (); | |
| 53 | cur = addr[i]; | |
| 54 | } | |
| 55 | while (cur <= expected); | |
| 56 | } | |
| 57 | ||
| 58 | #endif /* GOMP_DOACROSS_H */ |