usr/src/lib/common/i386/crti.s

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2001 by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26 /*
  27  * Copyright (c) 2013, Joyent, Inc.  All rights reserved.
  28  */
  29
  30 /*
  31  * These crt*.o modules are provided as the bare minimum required
  32  * from a crt*.o for inclusion in building low level system
  33  * libraries.  The are only be to included in libraries which
  34  * contain *no* C++ code and want to avoid the startup code
  35  * that the C++ runtime has introduced into the crt*.o modules.
  36  *
  37  * For further details - see bug#4433015
  38  */
  39
  40         .file   "crti.s"
  41
  42 /*
  43  * Note that when _init and _fini are called we have 16-byte alignment per the
  44  * ABI. We need to make sure that our asm leaves it such that subsequent calls
  45  * will be aligned. gcc expects stack alignment before the call instruction is
  46  * executed. Specifically if we call function foo(), the stack pointer will be
  47  * 0xc aligned after executing the call instruction and before executing foo's
  48  * prologue. Note that because 16-byte alignment also ensures 4-byte alignment
  49  * we will not be breaking compatibility with older applications.
  50  */
  51
  52 /*
  53  * _init function prologue
  54  */
  55         .section        .init,"ax"
  56         .globl  _init
  57         .type   _init,@function
  58         .align  16
  59 _init:
  60         pushl   %ebp
  61         movl    %esp, %ebp
  62         andl    $-16,%esp
  63         subl    $12,%esp
  64         pushl   %ebx
  65         call    .L1
  66 .L1:    popl    %ebx
  67         addl    $_GLOBAL_OFFSET_TABLE_+[.-.L1], %ebx
  68
  69 /*
  70  * _fini function prologue
  71  */
  72         .section        .fini,"ax"
  73         .globl  _fini
  74         .type   _fini,@function
  75         .align  16
  76 _fini:
  77         pushl   %ebp
  78         movl    %esp, %ebp
  79         andl    $-16,%esp
  80         subl    $12,%esp
  81         pushl   %ebx
  82         call    .L2
  83 .L2:    popl    %ebx
  84         addl    $_GLOBAL_OFFSET_TABLE_+[.-.L2], %ebx