about summary refs log tree commit diff
path: root/sysdeps/i386/pthread_spin_trylock.S
blob: bdebc71f9aafa65bafeca15c4a11217edf461053 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
/* Copyright (C) 2002-2020 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
   <https://www.gnu.org/licenses/>.  */

#include <sysdep.h>
#include <errno.h>


ENTRY (pthread_spin_trylock)
	movl	4(%esp), %edx
	movl	$1, %eax
	xorl	%ecx, %ecx
	lock
	cmpxchgl %ecx, (%edx)
	movl	$EBUSY, %eax
#ifdef HAVE_CMOV
	cmovel	%ecx, %eax
#else
	jne	0f
	movl	%ecx, %eax
0:
#endif
	ret
END (pthread_spin_trylock)