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      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  *  * Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  *  * Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in
     12  *    the documentation and/or other materials provided with the
     13  *    distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
     18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
     19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
     20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
     22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
     25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  */
     28 
     29 #include "../../bionic/libc_init_common.h"
     30 #include <stddef.h>
     31 #include <stdint.h>
     32 
     33 __attribute__ ((section (".preinit_array")))
     34 void (*__PREINIT_ARRAY__)(void) = (void (*)(void)) -1;
     35 
     36 __attribute__ ((section (".init_array")))
     37 void (*__INIT_ARRAY__)(void) = (void (*)(void)) -1;
     38 
     39 __attribute__ ((section (".fini_array")))
     40 void (*__FINI_ARRAY__)(void) = (void (*)(void)) -1;
     41 
     42 
     43 __LIBC_HIDDEN__  void do_mips_start(void *raw_args) {
     44   structors_array_t array;
     45   array.preinit_array = &__PREINIT_ARRAY__;
     46   array.init_array = &__INIT_ARRAY__;
     47   array.fini_array = &__FINI_ARRAY__;
     48 
     49   __libc_init(raw_args, NULL, &main, &array);
     50 }
     51 
     52 #if defined(__LP64__)
     53 
     54 /*
     55  * This function prepares the return address with a branch-and-link
     56  * instruction (bal) and then uses a .cpsetup to compute the Global
     57  * Offset Table (GOT) pointer ($gp). The $gp is then used to load
     58  * the address of _do_mips_start() into $t9 just before calling it.
     59  * Terminating the stack with a NULL return address.
     60  */
     61 __asm__ (
     62 "       .set push                   \n"
     63 "                                   \n"
     64 "       .text                       \n"
     65 "       .align  4                   \n"
     66 "       .type __start,@function     \n"
     67 "       .globl __start              \n"
     68 "       .globl  _start              \n"
     69 "                                   \n"
     70 "       .ent    __start             \n"
     71 "__start:                           \n"
     72 " _start:                           \n"
     73 "       .frame   $sp,32,$0          \n"
     74 "       .mask   0x80000000,-8       \n"
     75 "                                   \n"
     76 "       move    $a0, $sp            \n"
     77 "       daddiu  $sp, $sp, -32       \n"
     78 "                                   \n"
     79 "       .set noreorder              \n"
     80 "       bal     1f                  \n"
     81 "       nop                         \n"
     82 "1:                                 \n"
     83 "       .cpsetup $ra,16,1b          \n"
     84 "       .set reorder                \n"
     85 "                                   \n"
     86 "       sd      $0, 24($sp)         \n"
     87 "       jal     do_mips_start       \n"
     88 "                                   \n"
     89 "2:     b       2b                  \n"
     90 "       .end    __start             \n"
     91 "                                   \n"
     92 "       .set pop                    \n"
     93 );
     94 
     95 #else
     96 
     97 /*
     98  * This function prepares the return address with a branch-and-link
     99  * instruction (bal) and then uses a .cpload to compute the Global
    100  * Offset Table (GOT) pointer ($gp). The $gp is then used to load
    101  * the address of _do_start() into $t9 just before calling it.
    102  * Terminating the stack with a NULL return address.
    103  */
    104 __asm__ (
    105 "       .set push                   \n"
    106 "                                   \n"
    107 "       .text                       \n"
    108 "       .align  4                   \n"
    109 "       .type __start,@function     \n"
    110 "       .globl __start              \n"
    111 "       .globl  _start              \n"
    112 "                                   \n"
    113 "       .ent    __start             \n"
    114 "__start:                           \n"
    115 " _start:                           \n"
    116 "       .frame   $sp,32,$ra         \n"
    117 "       .mask   0x80000000,-4       \n"
    118 "                                   \n"
    119 "       .set noreorder              \n"
    120 "       bal     1f                  \n"
    121 "       nop                         \n"
    122 "1:                                 \n"
    123 "       .cpload $ra                 \n"
    124 "       .set reorder                \n"
    125 "                                   \n"
    126 "       move    $a0, $sp            \n"
    127 "       addiu   $sp, $sp, (-32)     \n"
    128 "       sw      $0, 28($sp)         \n"
    129 "       la      $t9, do_mips_start  \n"
    130 "       jalr    $t9                 \n"
    131 "                                   \n"
    132 "2:     b       2b                  \n"
    133 "       .end    __start             \n"
    134 "                                   \n"
    135 "       .set pop                    \n"
    136 );
    137 
    138 #endif
    139 
    140 #include "../../arch-common/bionic/__dso_handle.h"
    141 #include "atexit.h"
    142