nptl/sysdeps/unix/sysv/linux/i386/i486/sem_trywait.S

   1 /* Copyright (C) 2002-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <sysdep.h>
  20 #include <shlib-compat.h>
  21 #include <pthread-errnos.h>
  22 #include <lowlevellock.h>
  23
  24         .text
  25
  26         .globl  __new_sem_trywait
  27         .type   __new_sem_trywait,@function
  28         .align  16
  29 __new_sem_trywait:
  30         movl    4(%esp), %ecx
  31
  32         movl    (%ecx), %eax
  33 2:      testl   %eax, %eax
  34         jz      1f
  35
  36         leal    -1(%eax), %edx
  37         LOCK
  38         cmpxchgl %edx, (%ecx)
  39         jne     2b
  40         xorl    %eax, %eax
  41         ret
  42
  43 1:
  44 #ifdef PIC
  45         SETUP_PIC_REG(cx)
  46 #else
  47         movl    $3f, %ecx
  48 3:
  49 #endif
  50         addl    $_GLOBAL_OFFSET_TABLE_, %ecx
  51 #ifdef NO_TLS_DIRECT_SEG_REFS
  52         movl    errno@gotntpoff(%ecx), %edx
  53         addl    %gs:0, %edx
  54         movl    $EAGAIN, (%edx)
  55 #else
  56         movl    errno@gotntpoff(%ecx), %edx
  57         movl    $EAGAIN, %gs:(%edx)
  58 #endif
  59         orl     $-1, %eax
  60         ret
  61         .size   __new_sem_trywait,.-__new_sem_trywait
  62         versioned_symbol(libpthread, __new_sem_trywait, sem_trywait, GLIBC_2_1)
  63 #if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
  64         .global __old_sem_trywait
  65 __old_sem_trywait = __new_sem_trywait
  66         compat_symbol(libpthread, __old_sem_trywait, sem_trywait, GLIBC_2_0)
  67 #endif