sysdeps/unix/sysv/linux/i386/dl-sysdep.h

   1 /* System-specific settings for dynamic linker code.  i386 version.
   2    Copyright (C) 2002-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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 #ifndef _LINUX_I386_DL_SYSDEP_H
  20
  21 #include_next <dl-sysdep.h>
  22
  23 /* Traditionally system calls have been made using int $0x80.  A
  24    second method was introduced which, if possible, will use the
  25    sysenter/syscall instructions.  To signal the presence and where to
  26    find the code the kernel passes an AT_SYSINFO value in the
  27    auxiliary vector to the application.  */
  28 #define NEED_DL_SYSINFO 1
  29
  30 #ifndef __ASSEMBLER__
  31 extern void _dl_sysinfo_int80 (void) attribute_hidden;
  32 # define DL_SYSINFO_DEFAULT (uintptr_t) _dl_sysinfo_int80
  33 # define DL_SYSINFO_IMPLEMENTATION \
  34   asm (".text\n\t"                                                            \
  35        ".type _dl_sysinfo_int80,@function\n\t"                                \
  36        ".hidden _dl_sysinfo_int80\n"                                          \
  37        CFI_STARTPROC "\n"                                                     \
  38        "_dl_sysinfo_int80:\n\t"                                               \
  39        "int $0x80;\n\t"                                                       \
  40        "ret;\n\t"                                                             \
  41        CFI_ENDPROC "\n"                                                       \
  42        ".size _dl_sysinfo_int80,.-_dl_sysinfo_int80\n\t"                      \
  43        ".previous");
  44 #endif
  45
  46 #endif  /* dl-sysdep.h */