linuxthreads/sysdeps/ia64/pt-machine.h

   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 not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef _PT_MACHINE_H
  22 #define _PT_MACHINE_H   1
  23
  24 #include <ia64intrin.h>
  25
  26 #ifndef PT_EI
  27 # define PT_EI extern inline __attribute__ ((always_inline))
  28 #endif
  29
  30 extern long int testandset (int *spinlock);
  31 extern int __compare_and_swap (long int *p, long int oldval, long int newval);
  32
  33 /* Make sure gcc doesn't try to be clever and move things around on
  34    us. We need to use _exactly_ the address the user gave us, not some
  35    alias that contains the same information.  */
  36 #define __atomic_fool_gcc(x) (*(volatile struct { int a[100]; } *)x)
  37
  38 #ifndef ELF_MACHINE_NAME
  39
  40 #define NEED_SEPARATE_REGISTER_STACK
  41
  42 /* We want the OS to assign stack addresses.  */
  43 #define FLOATING_STACKS 1
  44
  45 /* Maximum size of the stack if the rlimit is unlimited.  */
  46 #define ARCH_STACK_MAX_SIZE     32*1024*1024
  47
  48 /* Get some notion of the current stack.  Need not be exactly the top
  49    of the stack, just something somewhere in the current frame.
  50    r12 (sp) is the stack pointer. */
  51 #define CURRENT_STACK_FRAME  stack_pointer
  52 register char *stack_pointer __asm__ ("sp");
  53
  54
  55 /* Register r13 (tp) is reserved by the ABI as "thread pointer". */
  56 struct _pthread_descr_struct;
  57 register struct _pthread_descr_struct *__thread_self __asm__("r13");
  58
  59 /* Return the thread descriptor for the current thread.  */
  60 #define THREAD_SELF  __thread_self
  61
  62 /* Initialize the thread-unique value.  */
  63 #define INIT_THREAD_SELF(descr, nr)  (__thread_self = (descr))
  64
  65
  66 /* Access to data in the thread descriptor is easy.  */
  67 #define THREAD_GETMEM(descr, member) \
  68   ((void) sizeof (descr), THREAD_SELF->member)
  69 #define THREAD_GETMEM_NC(descr, member) \
  70   ((void) sizeof (descr), THREAD_SELF->member)
  71 #define THREAD_SETMEM(descr, member, value) \
  72   ((void) sizeof (descr), THREAD_SELF->member = (value))
  73 #define THREAD_SETMEM_NC(descr, member, value) \
  74   ((void) sizeof (descr), THREAD_SELF->member = (value))
  75
  76
  77 /* Memory barrier */
  78 #define MEMORY_BARRIER() __sync_synchronize ()
  79
  80
  81 #define HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS
  82
  83 PT_EI int
  84 __compare_and_swap (long int *p, long int oldval, long int newval)
  85 {
  86   long int readval;
  87
  88   __asm__ __volatile__
  89        ("mov ar.ccv=%4;;\n\t"
  90         "cmpxchg8.acq %0=%1,%2,ar.ccv"
  91         : "=r" (readval), "=m" (__atomic_fool_gcc (p))
  92         : "r"(newval), "m" (__atomic_fool_gcc (p)), "r" (oldval)
  93         : "memory");
  94   return readval == oldval;
  95 }
  96
  97 PT_EI int
  98 __compare_and_swap_with_release_semantics (long int *p,
  99                                            long int oldval,
 100                                            long int newval)
 101 {
 102   long int readval;
 103
 104   __asm__ __volatile__
 105        ("mov ar.ccv=%4;;\n\t"
 106         "cmpxchg8.rel %0=%1,%2,ar.ccv"
 107         : "=r" (readval), "=m" (__atomic_fool_gcc (p))
 108         : "r"(newval), "m" (__atomic_fool_gcc (p)), "r" (oldval)
 109         : "memory");
 110   return readval == oldval;
 111 }
 112
 113 #endif /* ELF_MACHINE_NAME */
 114
 115 /* Spinlock implementation; required.  */
 116 PT_EI long int
 117 testandset (int *spinlock)
 118 {
 119   long int ret;
 120
 121   __asm__ __volatile__(
 122        "xchg4 %0=%1,%2"
 123        : "=r"(ret), "=m"(__atomic_fool_gcc (spinlock))
 124        : "r"(1), "m"(__atomic_fool_gcc (spinlock))
 125        : "memory");
 126
 127   return ret;
 128 }
 129
 130 /* Indicate that we are looping.  */
 131 #define BUSY_WAIT_NOP   __asm__ ("hint @pause")
 132
 133 #endif /* pt-machine.h */