Hi, i am suppose to create an assembly language program in which prints the numb

Question

Hi, i am suppose to create an assembly language program in which prints the numbers 1-100. When a number is divisble by 5 it prints "fizz" and when theres a 5 in the number it also prints out "fizz" I have got the first part printing 1-100 out to work but i am not sure why my ecx counter resets after it prints fizz. any help would be appreciated

section .text
extern puts
extern printf
global main

main:
L1:
inc ecx       ;ecx = 1
mov eax,ecx   ;eax = 1
xor ebx,ebx
xor edx,edx
mov ecx,eax
mov ebx, 5    ;ebx = 5
idiv ebx      ;eax / ebx
cmp edx,0     ; is eax = 0?
jz L2
jmp L3

L3:
push ecx      ;ecx = 1 onto stack
push a        ;calling string
call printf   ;printing string plus ecx
pop ecx       ; pops a (string)
pop ecx       ; pops 1
cmp ecx,100   ; ecx = 1
jl L1         ; return to loop
jmp exit

L2:
push ebx
push eax
push b
call printf
pop eax
pop eax
pop ebx
jmp L1

exit:
ret

Explanation / Answer

The assembly language program can be wriiten as follows-

.LC0:

.string "%d"

.LC1:

.string "fizz"

main:

pushq %rbp

movq %rsp, %rbp

subq $16, %rsp

movl $1, -16(%rbp)

.L3:

movl -16(%rbp), %eax

cmpl $100, %eax

jg .L2

leaq -16(%rbp), %rax

movq %rax, %rsi

movl $.LC0, %edi

movl $0, %eax

call printf

movl -16(%rbp), %eax

addl $1, %eax

movl %eax, -16(%rbp)

jmp .L3

.L2:

movl $1, -16(%rbp)

.L6:

movl -16(%rbp), %eax

cmpl $100, %eax

jg .L4

movl -16(%rbp), %ecx

movl $1717986919, %edx

movl %ecx, %eax

imull %edx

sarl %edx

movl %ecx, %eax

sarl $31, %eax

subl %eax, %edx

movl %edx, %eax

movl %eax, %edx

sall $2, %edx

addl %eax, %edx

movl %ecx, %eax

subl %edx, %eax

testl %eax, %eax

jne .L5

movl $.LC1, %edi

movl $0, %eax

call printf

.L5:

movl -16(%rbp), %eax

addl $1, %eax

movl %eax, -16(%rbp)

jmp .L6

.L4:

movl $1, -16(%rbp)

.L11:

movl -16(%rbp), %eax

cmpl $100, %eax

jg .L7

movl -16(%rbp), %eax

movl %eax, -4(%rbp)

movl $10, -8(%rbp)

.L10:

cmpl $0, -4(%rbp)

je .L8

movl -4(%rbp), %eax

cltd

idivl -8(%rbp)

movl %eax, -12(%rbp)

movl -4(%rbp), %eax

cltd

idivl -8(%rbp)

movl %edx, -4(%rbp)

movl -8(%rbp), %ecx

movl $1717986919, %edx

movl %ecx, %eax

imull %edx

sarl $2, %edx

movl %ecx, %eax

sarl $31, %eax

subl %eax, %edx

movl %edx, %eax

movl %eax, -8(%rbp)

cmpl $5, -12(%rbp)

jne .L10

movl $.LC1, %edi

movl $0, %eax

call printf

jmp .L10

.L8:

movl -16(%rbp), %eax

addl $1, %eax

movl %eax, -16(%rbp)

jmp .L11

.L7:

movl $0, %eax

leave

ret

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