crt1.s 690 B

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  1. /* Written 2011 Nicholas J. Kain, released as Public Domain */
  2. .weak _init
  3. .weak _fini
  4. .text
  5. .global _start
  6. _start:
  7. xor %rbp,%rbp /* rbp:undefined -> mark as zero 0 (ABI) */
  8. mov %rdx,%r9 /* 6th arg: ptr to register with atexit() */
  9. pop %rsi /* 2nd arg: argc */
  10. mov %rsp,%rdx /* 3rd arg: argv */
  11. andq $-16,%rsp /* align stack pointer */
  12. push %rax /* 8th arg: glibc ABI compatible */
  13. push %rsp /* 7th arg: glibc ABI compatible */
  14. mov $_fini,%r8 /* 5th arg: fini/dtors function */
  15. mov $_init,%rcx /* 4th arg: init/ctors function */
  16. mov $main,%rdi /* 1st arg: application entry ip */
  17. call __libc_start_main /* musl init will run the program */
  18. 1: jmp 1b