1 /* Machine-dependent pthreads configuration and inline functions.
2
3 Copyright (C) 1996, 1997, 1998, 2000, 2002, 2003, 2004
4 Free Software Foundation, Inc.
5 This file is part of the GNU C Library.
6 Contributed by Ralf Baechle <ralf@gnu.org>.
7 Based on the Alpha version by Richard Henderson <rth@tamu.edu>.
8
9 The GNU C Library is free software; you can redistribute it and/or
10 modify it under the terms of the GNU Lesser General Public License as
11 published by the Free Software Foundation; either version 2.1 of the
12 License, or (at your option) any later version.
13
14 The GNU C Library is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 Lesser General Public License for more details.
18
19 You should have received a copy of the GNU Lesser General Public
20 License along with the GNU C Library; see the file COPYING.LIB. If
21 not, see <http://www.gnu.org/licenses/>. */
22
23 #ifndef _PT_MACHINE_H
24 #define _PT_MACHINE_H 1
25
26 #include <features.h>
27
28 #ifndef PT_EI
29 # define PT_EI __extern_always_inline
30 #endif
31
32 /* Copyright (C) 2000, 2002 Free Software Foundation, Inc.
33 This file is part of the GNU C Library.
34 Contributed by Maciej W. Rozycki <macro@ds2.pg.gda.pl>, 2000. */
35 static __inline__ int
__NTH(_test_and_set (int * p,int v))36 __NTH (_test_and_set (int *p, int v))
37 {
38 int r, t;
39
40 __asm__ __volatile__
41 ("/* Inline test and set */\n"
42 "1:\n\t"
43 ".set push\n\t"
44 ".set mips2\n\t"
45 "ll %0,%3\n\t"
46 "move %1,%4\n\t"
47 "beq %0,%4,2f\n\t"
48 "sc %1,%2\n\t"
49 ".set pop\n\t"
50 "beqz %1,1b\n"
51 "2:\n\t"
52 "/* End test and set */"
53 : "=&r" (r), "=&r" (t), "=m" (*p)
54 : "m" (*p), "r" (v)
55 : "memory");
56
57 return r;
58 }
59
60
61 /* Spinlock implementation; required. */
62
63 PT_EI long int
testandset(int * spinlock)64 testandset (int *spinlock)
65 {
66 return _test_and_set (spinlock, 1);
67 }
68
69
70 /* Get some notion of the current stack. Need not be exactly the top
71 of the stack, just something somewhere in the current frame. */
72 #define CURRENT_STACK_FRAME stack_pointer
73 register char * stack_pointer __asm__ ("$29");
74
75
76 /* Compare-and-swap for semaphores. */
77
78 #define HAS_COMPARE_AND_SWAP
79 PT_EI int
__compare_and_swap(long int * p,long int oldval,long int newval)80 __compare_and_swap (long int *p, long int oldval, long int newval)
81 {
82 long int ret, temp;
83
84 __asm__ __volatile__
85 ("/* Inline compare & swap */\n"
86 "1:\n\t"
87 ".set push\n\t"
88 ".set mips2\n\t"
89 "ll %1,%5\n\t"
90 "move %0,$0\n\t"
91 "bne %1,%3,2f\n\t"
92 "move %0,%4\n\t"
93 "sc %0,%2\n\t"
94 ".set pop\n\t"
95 "beqz %0,1b\n"
96 "2:\n\t"
97 "/* End compare & swap */"
98 : "=&r" (ret), "=&r" (temp), "=m" (*p)
99 : "r" (oldval), "r" (newval), "m" (*p)
100 : "memory");
101
102 return ret;
103 }
104
105 #endif /* pt-machine.h */
106