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;
; file: math.asm
; This program demonstrates how the integer multiplication and division
; instructions work.
;
; To create executable:
; nasm -f coff math.asm
; gcc -o math math.o driver.c asm_io.o

%include "asm_io.inc"

segment .data
;
; Output strings
;
prompt db "Enter a number: ", 0
square_msg db "Square of input is ", 0
cube_msg db "Cube of input is ", 0
cube25_msg db "Cube of input times 25 is ", 0
quot_msg db "Quotient of cube/100 is ", 0
rem_msg db "Remainder of cube/100 is ", 0
neg_msg db "The negation of the remainder is ", 0

segment .bss
input resd 1


segment .text
global asm_main
asm_main:
enter 0,0 ; setup routine
pusha

mov eax, prompt
call print_string

call read_int
mov [input], eax

imul eax ; edx:eax = eax * eax
mov ebx, eax ; save answer in ebx
mov eax, square_msg
call print_string
mov eax, ebx
call print_int
call print_nl

mov ebx, eax
imul ebx, [input] ; ebx *= [input]
mov eax, cube_msg
call print_string
mov eax, ebx
call print_int
call print_nl

imul ecx, ebx, 25 ; ecx = ebx*25
mov eax, cube25_msg
call print_string
mov eax, ecx
call print_int
call print_nl

mov eax, ebx
cdq ; initialize edx by sign extension
mov ecx, 100 ; can't divide by immediate value
idiv ecx ; edx:eax / ecx
mov ecx, eax ; save quotient into ecx
mov eax, quot_msg
call print_string
mov eax, ecx
call print_int
call print_nl
mov eax, rem_msg
call print_string
mov eax, edx
call print_int
call print_nl

neg edx ; negate the remainder
mov eax, neg_msg
call print_string
mov eax, edx
call print_int
call print_nl

popa
mov eax, 0 ; return back to C
leave
ret