blob: fb41c41e9e1e9693bd171dd1776eb14c549313c7 (
plain)
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
39
40
41
42
43
44
45
46
|
/*
* sysdeps/v850/pt-machine.h -- v850-specific pthread definitions
*
* Copyright (C) 2002 NEC Electronics Corporation
* Copyright (C) 2002 Miles Bader <miles@gnu.org>
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License. See the file COPYING.LIB in the main
* directory of this archive for more details.
*
* Written by Miles Bader <miles@gnu.org>
*/
#ifndef PT_EI
# define PT_EI extern inline
#endif
/* Get some notion of the current stack. Need not be exactly the top
of the stack, just something somewhere in the current frame. */
#define CURRENT_STACK_FRAME __stack_pointer
register char *__stack_pointer __asm__ ("sp");
#define HAS_COMPARE_AND_SWAP
/* Atomically: If *PTR == OLD, set *PTR to NEW and return true,
otherwise do nothing and return false. */
PT_EI int
__compare_and_swap (long *ptr, long old, long new)
{
unsigned long psw;
/* disable interrupts */
__asm__ __volatile__ ("stsr psw, %0; di" : "=&r" (psw));
if (likely (*ptr == old))
{
*ptr = new;
__asm__ __volatile__ ("ldsr %0, psw" :: "r" (psw)); /* re-enable */
return 1;
}
else
{
__asm__ __volatile__ ("ldsr %0, psw" :: "r" (psw)); /* re-enable */
return 0;
}
}
|
