crt0.S 2.3 KB

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  1. /*
  2. * Copyright (C) 2003 by Erik Andersen
  3. *
  4. * This program is free software; you can redistribute it and/or modify it
  5. * under the terms of the GNU Library General Public License as published by
  6. * the Free Software Foundation; either version 2 of the License, or (at your
  7. * option) any later version.
  8. *
  9. * This program is distributed in the hope that it will be useful, but WITHOUT
  10. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
  12. * for more details.
  13. *
  14. * You should have received a copy of the GNU Library General Public License
  15. * along with this program; if not, write to the Free Software Foundation,
  16. * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  17. */
  18. /* Integer registers. */
  19. #define r0 0
  20. #define r1 1
  21. #define r2 2
  22. #define r3 3
  23. #define r4 4
  24. #define r5 5
  25. #define r6 6
  26. #define r7 7
  27. #define r8 8
  28. #define r9 9
  29. #define r13 13
  30. #define r31 31
  31. #include <features.h>
  32. .section ".text"
  33. .globl _start
  34. .type _start,@function
  35. #if defined L_crt0 || ! defined __UCLIBC_CTOR_DTOR__
  36. .type __uClibc_main,%function
  37. #else
  38. .weak _init
  39. .weak _fini
  40. .type __uClibc_start_main,%function
  41. #endif
  42. /* Stick in a dummy reference to main(), so that if an application
  43. * is linking when the main() function is in a static library (.a)
  44. * we can be sure that main() actually gets linked in */
  45. .type main,%function
  46. _start:
  47. /* Save the stack pointer, in case we're statically linked under Linux. */
  48. mr r9,r1
  49. /* Set up an initial stack frame, and clear the LR. */
  50. clrrwi r1,r1,4
  51. li r0,0
  52. stwu r1,-16(r1)
  53. mtlr r0
  54. stw r0,0(r1)
  55. /* find argc from the stack pointer */
  56. lwz r3,0(r9)
  57. /* find argv one word offset from the stack pointer */
  58. addi r4,r9,4
  59. /* find environment pointer (argv+argc+1) */
  60. lwz r5,0(r9)
  61. addi r5,r5,1
  62. rlwinm r5,r5,2,0,29
  63. add r5,r5,r4
  64. /* Ok, now run uClibc's main() -- shouldn't return */
  65. #if defined L_crt0 || ! defined __UCLIBC_CTOR_DTOR__
  66. bl __uClibc_main
  67. #else
  68. lis r6,_init@ha # load top 16 bits
  69. addi r6,r6,_init@l # load bottom 16 bits
  70. lis r7,_fini@ha # load top 16 bits of &msg
  71. addi r7,r7,_fini@l # load bottom 16 bits
  72. bl __uClibc_start_main
  73. #endif
  74. .size _start,.-_start
  75. .section ".data"
  76. .globl __data_start
  77. __data_start: