mov (%rsp),%rdi /* move argc into 1st argument slot */
lea 4(%rsp),%rsi /* move argv into 2nd argument slot */
/* in case the dynlinker was called directly, it sets the "consumed"
argv values to -1. so we must loop over the array as long as -1
is in the top argv slot, decrement argc, and then set the stackpointer
to the new argc as well as argc's new value.
as the x32 abi has longs in the argv array, we cannot use push/pop.*/
movl (%rsp),%edi /* copy argc into edi */
xor %rdx,%rdx /* we use rdx as an offset to the current argv member */
1: dec %edi
addl $4, %edx
movl (%rsp, %rdx), %esi
subl $4, %edx
lea (%rsp, %rdx), %rsp /* set rsp to new argv[-1] */
movl %edi, (%rsp) /* write new argc there */