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/* Copyright (C) 2005, 2008, 2009 Free Software Foundation, Inc.
Contributed by Richard Henderson <rth@redhat.com>.
This file is part of the GNU OpenMP Library (libgomp).
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
<http://www.gnu.org/licenses/>. */
/* Provide target-specific access to the futex system call. */
#include <sys/syscall.h>
static inline long
sys_futex0(int *addr, long op, int val)
{
register long out0 asm ("out0") = (long) addr;
register long out1 asm ("out1") = op;
register long out2 asm ("out2") = val;
register long out3 asm ("out3") = 0;
register long r8 asm ("r8");
register long r10 asm ("r10");
register long r15 asm ("r15") = SYS_futex;
__asm __volatile ("break 0x100000"
: "=r"(r15), "=r"(out0), "=r"(out1), "=r"(out2), "=r"(out3),
"=r"(r8), "=r"(r10)
: "r"(r15), "r"(out0), "r"(out1), "r"(out2), "r"(out3)
: "memory", "out4", "out5", "out6", "out7",
/* Non-stacked integer registers, minus r8, r10, r15. */
"r2", "r3", "r9", "r11", "r12", "r13", "r14", "r16", "r17", "r18",
"r19", "r20", "r21", "r22", "r23", "r24", "r25", "r26", "r27",
"r28", "r29", "r30", "r31",
/* Predicate registers. */
"p6", "p7", "p8", "p9", "p10", "p11", "p12", "p13", "p14", "p15",
/* Non-rotating fp registers. */
"f6", "f7", "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
/* Branch registers. */
"b6");
return r8 & r10;
}
static inline void
futex_wait (int *addr, int val)
{
long err = sys_futex0 (addr, gomp_futex_wait, val);
if (__builtin_expect (err == ENOSYS, 0))
{
gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
sys_futex0 (addr, gomp_futex_wait, val);
}
}
static inline void
futex_wake (int *addr, int count)
{
long err = sys_futex0 (addr, gomp_futex_wake, count);
if (__builtin_expect (err == ENOSYS, 0))
{
gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
sys_futex0 (addr, gomp_futex_wake, count);
}
}
static inline void
cpu_relax (void)
{
__asm volatile ("hint @pause" : : : "memory");
}
static inline void
atomic_write_barrier (void)
{
__sync_synchronize ();
}
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