Depth of parentheses in Assembly x86 - c

Question

I make program in order to find maximum depth of parenthesis in String.
At first, I make C program with Assembly code, it works good:
#include <stdio.h>
int main(){
char *s ="((abc) ∗ (ab+(ab)∗(cdx7)))−xxab((()))c";
int x;
asm volatile (
".intel_syntax noprefix;"
"mov eax,%1;"
"lea ebx,[eax];"
"xor eax,eax;" ecx - currentDepth, edx - MaxDepth
"xor ecx,ecx;"
"xor edx,edx;"
"loop:"
"mov al,[ebx];"
"or al, al;" // check if end of string
"jz print;" // if end jump to print
"cmp al, '(';"
"je increase;"
"cmp al,')';"
"je decrease;"
"inc ebx;" // next char
"jmp loop;"
"increase:"
"inc ecx; cmp edx,ecx;js changeMax;inc ebx;jmp loop;"
"changeMax:"
"mov edx,ecx; inc ebx; jmp loop;"
"decrease:"
"dec ecx;inc ebx;jmp loop;"
"print:"
"mov %0, edx;"
".att_syntax prefix;"
: "=r" (x)
: "r" (s)
: "eax", "ebx", "ecx", "edx"
);
printf("%d", x);
return 0;
}
But I have to make it in pure Assembler with .s extension, so i try this:
.intel_syntax noprefix
.globl main
.text
main:
mov eax,offset expr
lea ebx,[eax]
xor eax,eax
xor ecx,ecx
xor edx,edx
loop:
mov al,[ebx]
or al,al
jz print
cmp al,'('
je increase
cmp al,')'
je decrease
inc ebx
jmp loop
increase:
inc ecx
cmp edx,ecx
js changeMax
inc ebx
jmp loop
changeMax:
mov edx,ecx
inc ebx
jmp loop
decrease:
dec ecx
inc ebx
jmp loop
print:
push edx
call printf
data:
mesg: .ascii "%d\n"
expr: .ascii "((x))"
But I got segmentation fault(core dumped)
Maybe labels are working differently than in first program in c.
But I don't know, please help me.
UPDATE
Thank you Jester
I edited label print, now it print out the result, but after that I still get segmentation fault.
print:
push edx
mov edx, offset mesg
push edx
call printf
ret
Ok, I remove it from the stack. Now i don't get segmentation fault, but after the result i have some rubbish text
print:
push edx
mov edx, offset mesg
push edx
call printf
add esp,8
ret
xor edx,edx
ret
Output:
2
f�f��UWVS������×
Update 2
Ok, everything works right now, I use string from command line ./a.out '((x))'
Someone can check that everything is ok.
.intel_syntax noprefix
.globl main
.text
main:
pop eax #return address
pop eax #return argc
pop eax #return argv
mov eax,[eax+4] #argv[1]
sub esp,12 #return stack to the right position
lea ebx,[eax]
xor eax,eax
xor ecx,ecx
xor edx,edx
loop:
mov al,[ebx]
or al,al
jz print
cmp al,'('
je increase
cmp al,')'
je decrease
inc ebx
jmp loop
increase:
inc ecx
cmp edx,ecx
js changeMax
inc ebx
jmp loop
changeMax:
mov edx,ecx
inc ebx
jmp loop
decrease:
dec ecx
inc ebx
jmp loop
print:
push edx
mov edx, offset mesg
push edx
call printf
add esp,8
ret
mov edx,0
ret
data:
mesg: .asciz "%d\n"