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.global _start
_start:
push %ebx
push %ecx
cmp $0,_impure_ptr
jne skipzero
movl $0xf5000000, _impure_ptr
mov $0xf5000000,%ebx
allzero:
movl $0, (%ebx)
add $4, %ebx
cmp $0xf5001000,%ebx
jne allzero
skipzero:
mov _impure_ptr,%eax
mov $0xf5000000,%ebx
copy:
mov (%eax),%ecx
mov %ecx,(%ebx)
add $4, %ebx
add $4, %eax
cmp $0xf5001000,%ebx
jne copy
movl $0xf5000000, _impure_ptr
pop %ecx
pop %ebx
# environment adress was passed on stack
pop %eax
mov %eax, environ
# call main (argc and argv are on the stack)
call main
# push exit code and pass to _exit syscall
push %eax
call exit
# this should never be reached!
.wait:
hlt
jmp .wait
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