glibc/sysdeps/x86_64/nptl/pthread_spin_trylock.S

38 lines
1.1 KiB
ArmAsm

/* Copyright (C) 2002-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <pthread-errnos.h>
#include <sysdep.h>
#ifdef UP
# define LOCK
#else
# define LOCK lock
#endif
ENTRY(pthread_spin_trylock)
movl $1, %eax
xorl %ecx, %ecx
LOCK
cmpxchgl %ecx, (%rdi)
movl $EBUSY, %eax
cmovel %ecx, %eax
retq
END(pthread_spin_trylock)