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| | /* Written 2011 Nicholas J. Kain, released as Public Domain */
.weak _init
.weak _fini
.text
.global _start
_start:
xor %rbp,%rbp /* rbp:undefined -> mark as zero 0 (ABI) */
mov %rdx,%r9 /* 6th arg: ptr to register with atexit() */
pop %rsi /* 2nd arg: argc.
we pop 2 words from the stack,
so rsi contains argv in the high bits and argc in the low bits*/
movl %esi, %esi /* clear the upper bits of the argc argument */
mov %rsp,%rdx /* copy address to first argv member into rdx, the reg for the 3rd arg */
subq $4, %rdx
andq $-16,%rsp /* align stack pointer */
mov $_fini,%r8 /* 5th arg: fini/dtors function */
mov $_init,%rcx /* 4th arg: init/ctors function */
mov $main,%rdi /* 1st arg: application entry ip */
call __libc_start_main /* musl init will run the program */
1: jmp 1b
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