summaryrefslogtreecommitdiff
path: root/linuxthreads/sysdeps/powerpc/powerpc64/pt-machine.h
blob: 562e69fa18ef0293b18a0d370c288a93f9c27f8e (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
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/* Machine-dependent pthreads configuration and inline functions.
   powerpc version.
   Copyright (C) 2002, 2003 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If
   not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* These routines are from Appendix G of the 'PowerPC 601 RISC Microprocessor
   User's Manual', by IBM and Motorola.  */

#ifndef _PT_MACHINE_H
#define _PT_MACHINE_H   1

#ifndef PT_EI
# define PT_EI extern inline __attribute__ ((always_inline))
#endif

extern long int testandset (int *spinlock);
extern int __compare_and_swap (long int *p, long int oldval, long int newval);
extern int __compare_and_swap32 (int *p, int oldval, int newval);

/* For multiprocessor systems, we want to ensure all memory accesses
   are completed before we reset a lock.  On other systems, we still
   need to make sure that the compiler has flushed everything to memory.  */
#define MEMORY_BARRIER() __asm__ __volatile__ ("lwsync" : : : "memory")
#define READ_MEMORY_BARRIER() __asm__ __volatile__ ("lwsync" : : : "memory")
#define WRITE_MEMORY_BARRIER() __asm__ __volatile__ ("eieio" : : : "memory")

/* We want the OS to assign stack addresses.  */
#define FLOATING_STACKS 1

/* Maximum size of the stack if the rlimit is unlimited.  */
#define ARCH_STACK_MAX_SIZE     16*1024*1024

/* 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__ ("r1");

/* Register r13 (tp) is reserved by the ABI as "thread pointer". */
struct _pthread_descr_struct;
register struct _pthread_descr_struct *__thread_self __asm__("r13");

/* Return the thread descriptor for the current thread.  */
#define THREAD_SELF  __thread_self

/* Initialize the thread-unique value.  */
#define INIT_THREAD_SELF(descr, nr)  (__thread_self = (descr))

/* Access to data in the thread descriptor is easy.  */
#define THREAD_GETMEM(descr, member) \
  ((void) (descr), THREAD_SELF->member)
#define THREAD_GETMEM_NC(descr, member) \
  ((void) (descr), THREAD_SELF->member)
#define THREAD_SETMEM(descr, member, value) \
  ((void) (descr), THREAD_SELF->member = (value))
#define THREAD_SETMEM_NC(descr, member, value) \
  ((void) (descr), THREAD_SELF->member = (value))

/* Compare-and-swap for semaphores. */
/* note that test-and-set(x) is the same as !compare-and-swap(x, 0, 1) */

#define HAS_COMPARE_AND_SWAP
#define HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS

PT_EI int
__compare_and_swap (long int *p, long int oldval, long int newval)
{
  long int ret;

  __asm__ __volatile__ (
	   "0:    ldarx %0,0,%1 ;"
	   "      xor. %0,%3,%0;"
	   "      bne 1f;"
	   "      stdcx. %2,0,%1;"
	   "      bne- 0b;"
	   "1:    "
	: "=&r"(ret)
	: "r"(p), "r"(newval), "r"(oldval)
	: "cr0", "memory");
  /* This version of __compare_and_swap is to be used when acquiring
     a lock, so we don't need to worry about whether other memory
     operations have completed, but we do need to be sure that any loads
     after this point really occur after we have acquired the lock.  */
  __asm__ __volatile__ ("isync" : : : "memory");
  return (int)(ret == 0);
}

PT_EI int
__compare_and_swap_with_release_semantics (long int *p,
					   long int oldval, long int newval)
{
  long int ret;

  MEMORY_BARRIER ();
  __asm__ __volatile__ (
	   "0:    ldarx %0,0,%1 ;"
	   "      xor. %0,%3,%0;"
	   "      bne 1f;"
	   "      stdcx. %2,0,%1;"
	   "      bne- 0b;"
	   "1:    "
	: "=&r"(ret)
	: "r"(p), "r"(newval), "r"(oldval)
	: "cr0", "memory");
  return (int)(ret == 0);
}

PT_EI int
__compare_and_swap32 (int *p, int oldval, int newval)
{
  int ret;

  __asm__ __volatile__ (
	   "0:    lwarx %0,0,%1 ;"
	   "      xor. %0,%3,%0;"
	   "      bne 1f;"
	   "      stwcx. %2,0,%1;"
	   "      bne- 0b;"
	   "1:    "
	: "=&r"(ret)
	: "r"(p), "r"(newval), "r"(oldval)
	: "cr0", "memory");
  /* This version of __compare_and_swap is to be used when acquiring
     a lock, so we don't need to worry about whether other memory
     operations have completed, but we do need to be sure that any loads
     after this point really occur after we have acquired the lock.  */
  __asm__ __volatile__ ("isync" : : : "memory");
  return (int)(ret == 0);
}

PT_EI int
__compare_and_swap32_with_release_semantics (long int *p,
					   long int oldval, long int newval)
{
  long int ret;

  MEMORY_BARRIER ();
  __asm__ __volatile__ (
	   "0:    lwarx %0,0,%1 ;"
	   "      xor. %0,%3,%0;"
	   "      bne 1f;"
	   "      stwcx. %2,0,%1;"
	   "      bne- 0b;"
	   "1:    "
	: "=&r"(ret)
	: "r"(p), "r"(newval), "r"(oldval)
	: "cr0", "memory");
  return (int)(ret == 0);
}

PT_EI long int
testandset (int *p)
{
  long int ret, val = 1;

  MEMORY_BARRIER ();
  __asm__ __volatile__ (
	   "0:    lwarx %0,0,%1 ;"
	   "      cmpwi  0,%0,0;"
	   "      bne 1f;"
	   "      stwcx. %2,0,%1;"
	   "      bne- 0b;"
	   "1:    "
	: "=&r"(ret)
	: "r"(p), "r" (val)
	: "cr0", "memory");
  MEMORY_BARRIER ();
  return ret != 0;
}

#endif /* pt-machine.h */