%include "MY_IO.h"

; Because my memory is not working
;   x /11g $rsp

section .data
        base  dd  2
        power dd  12

section .bss

        buffer resb 16

section .text
   global _start

Power:
    ; parameters:
    ;    rdi: the base
    ;    esi: the power
    ; set up for the function.
    push rbp      ; save the current base pointer
    mov rbp, rsp  ; set the base pointer to point to the current stack pointer
    push rsi      ; not needed but we want to look at it.

    ; if power == 0
    test esi, esi
    jnz power_recurse

    mov rax, 1  ; rax = 0
    jmp power_exit

power_recurse:
    
    dec esi    ; power--
    call Power ; rax = power(base, power)
    mul edi    ; rax = base * rax

power_exit:
    ; at this point, rax contains the return value
    ;   right now the stack contains    ra, rbp, esi

    pop rsi    ; remove esi from the stack
    pop rbp    ; restore the base pointer 
    ret       

_start:
    
    mov edi, [base]
    mov esi, [power]
    call Power

    mov  rdi, rax
    call PRINT_INT

    ; Exit
    mov eax, SYS_EXIT
    mov edx, SUCCESS
    syscall