; ASM implementation of a while loop
;
; while (condition) {
;    body
; }

; include directives
global asm_main
%include "../lib/asm_io.inc"

segment .data
    ; DX directives (read only, static data)

segment .bss
    ; RESX directives (writable data)

segment .text
asm_main:                   ; entry point (called from driver.c)
    ; instructions

    enter 0,0               ; Initialize register EBP
    pusha                   ; Push register contents to the stack
    ;

    mov   ecx, 1            ; sum

while:
    jo    end_while         ; end loop if OF flag is set

    ;body of loop
    mov   eax, ecx          ; move value to EAX to print
    call  print_int         ; print our value
    call  print_nl
    add   ecx, ecx          ; add number

    jmp   while             ; continue loop

end_while:

    dump_regs  0;           ; verify OF flga

    ;
    popa                    ; Restore register data from the stack
    mov    eax, 0           ; flush EAX of data
    leave                   ; restore the stack
    ret                     ; Return from main back into C library wrapper