1 /* Machine-dependent pthreads configuration and inline functions.
2 IA-64 version.
3 Copyright (C) 1999, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public License as
8 published by the Free Software Foundation; either version 2.1 of the
9 License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; see the file COPYING.LIB. If
18 not, see <http://www.gnu.org/licenses/>. */
19
20 #ifndef _PT_MACHINE_H
21 #define _PT_MACHINE_H 1
22
23 #include <features.h>
24 #include <ia64intrin.h>
25
26 #include <sys/types.h>
27 extern int __clone2 (int (*__fn) (void *__arg), void *__child_stack_base,
28 size_t __child_stack_size, int __flags, void *__arg, ...);
29
30 #ifndef PT_EI
31 # define PT_EI __extern_always_inline
32 #endif
33
34 /* Make sure gcc doesn't try to be clever and move things around on
35 us. We need to use _exactly_ the address the user gave us, not some
36 alias that contains the same information. */
37 #define __atomic_fool_gcc(x) (*(volatile struct { int a[100]; } *)x)
38
39 #ifndef ELF_MACHINE_NAME
40
41 #define NEED_SEPARATE_REGISTER_STACK
42
43 /* We want the OS to assign stack addresses. */
44 #define FLOATING_STACKS 1
45
46 /* Maximum size of the stack if the rlimit is unlimited. */
47 #define ARCH_STACK_MAX_SIZE 32*1024*1024
48
49 /* Get some notion of the current stack. Need not be exactly the top
50 of the stack, just something somewhere in the current frame.
51 r12 (sp) is the stack pointer. */
52 #define CURRENT_STACK_FRAME stack_pointer
53 register char *stack_pointer __asm__ ("sp");
54
55
56 /* Register r13 (tp) is reserved by the ABI as "thread pointer". */
57 struct _pthread_descr_struct;
58 register struct _pthread_descr_struct *__thread_self __asm__("r13");
59
60 /* Return the thread descriptor for the current thread. */
61 #define THREAD_SELF __thread_self
62
63 /* Initialize the thread-unique value. */
64 #define INIT_THREAD_SELF(descr, nr) (__thread_self = (descr))
65
66
67 /* Access to data in the thread descriptor is easy. */
68 #define THREAD_GETMEM(descr, member) \
69 ((void) sizeof (descr), THREAD_SELF->member)
70 #define THREAD_GETMEM_NC(descr, member) \
71 ((void) sizeof (descr), THREAD_SELF->member)
72 #define THREAD_SETMEM(descr, member, value) \
73 ((void) sizeof (descr), THREAD_SELF->member = (value))
74 #define THREAD_SETMEM_NC(descr, member, value) \
75 ((void) sizeof (descr), THREAD_SELF->member = (value))
76
77
78 /* Memory barrier */
79 #define MEMORY_BARRIER() __sync_synchronize ()
80
81
82 #define HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS
83
84 PT_EI int
__compare_and_swap(long int * p,long int oldval,long int newval)85 __compare_and_swap (long int *p, long int oldval, long int newval)
86 {
87 long int readval;
88
89 __asm__ __volatile__
90 ("mov ar.ccv=%4;;\n\t"
91 "cmpxchg8.acq %0=%1,%2,ar.ccv"
92 : "=r" (readval), "=m" (__atomic_fool_gcc (p))
93 : "r"(newval), "m" (__atomic_fool_gcc (p)), "r" (oldval)
94 : "memory");
95 return readval == oldval;
96 }
97
98 PT_EI int
__compare_and_swap_with_release_semantics(long int * p,long int oldval,long int newval)99 __compare_and_swap_with_release_semantics (long int *p,
100 long int oldval,
101 long int newval)
102 {
103 long int readval;
104
105 __asm__ __volatile__
106 ("mov ar.ccv=%4;;\n\t"
107 "cmpxchg8.rel %0=%1,%2,ar.ccv"
108 : "=r" (readval), "=m" (__atomic_fool_gcc (p))
109 : "r"(newval), "m" (__atomic_fool_gcc (p)), "r" (oldval)
110 : "memory");
111 return readval == oldval;
112 }
113
114 #endif /* ELF_MACHINE_NAME */
115
116 /* Spinlock implementation; required. */
117 PT_EI long int
testandset(int * spinlock)118 testandset (int *spinlock)
119 {
120 long int ret;
121
122 __asm__ __volatile__(
123 "xchg4 %0=%1,%2"
124 : "=r"(ret), "=m"(__atomic_fool_gcc (spinlock))
125 : "r"(1), "m"(__atomic_fool_gcc (spinlock))
126 : "memory");
127
128 return ret;
129 }
130
131 /* Indicate that we are looping. */
132 #define BUSY_WAIT_NOP __asm__ ("hint @pause")
133
134 #endif /* pt-machine.h */
135