blob: 33981aa5db8873708dcbd8824110007f070c1a26 [file] [log] [blame]
/* Copyright (C) 2015-2022 Free Software Foundation, Inc.
Contributed by Mentor Embedded.
This file is part of the GNU Offloading and Multi Processing Library
Libgomp is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for
more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<>. */
/* This is the AMD GCN implementation of doacross spinning. */
#include "libgomp.h"
static inline int
cpu_relax (void)
/* This can be implemented as just a memory barrier, but a sleep seems
like it should allow the wavefront to yield (maybe?)
Use the shortest possible sleep time of 1*64 cycles. */
asm volatile ("s_sleep\t1" ::: "memory");
return 0;
static inline void doacross_spin (unsigned long *addr, unsigned long expected,
unsigned long cur)
/* Prevent compiler from optimizing based on bounds of containing object. */
asm ("" : "+r" (addr));
/* An alternative implementation might use s_setprio to lower the
priority temporarily, and then restore it after. */
int i = cpu_relax ();
cur = addr[i];
while (cur <= expected);
#endif /* GOMP_DOACROSS_H */