my strlen

//(c)Terminator
#include <stdio.h>

#ifdef __GNUC__

//Длинна строки(32-бит синтаксис AT)
size_t  __length(const char* s){
    size_t n = 0;
    asm("movl %0, %%esi"::"d"(s));
    asm("movl %esi, %edi\n\t"
        "__next:\n\t"
        "mov (%esi), %al\n\t"
        "or  $0, %al\n\t"
        "jz __end;\n\t"
        "incl %esi\n\t"
        "jmp __next;\n\t"
        "__end:\n\t"
        "subl %edi, %esi\n\t");
    asm("movl %%esi, %0" :"=r"(n));
    return n;
}

#else

//Длинна строки(32-бит синтаксис INTEL)
size_t  __length(const char* s){
    size_t n = 0;
    __asm {
        mov esi, s
__next:
        mov al, byte ptr[esi]
        or  al, 0
        jz  __end;
        inc  esi
        jmp __next;
__end:
        mov edx,  dword ptr s
        sub esi,  edx
        mov dword ptr n, esi
    };
    return n;
}

#endif


int  main(void){
    char str[] = "Terminator Cyborg";
    printf("length: %u\n", __length(str));
    return 0;
}