.data
string:         .asciz "Test"

.text
.globl  main

main:
        pushl   %ebp
        movl    %esp, %ebp

        pushl   %edi
        xorb    %al, %al
        movl    $-1, %ecx
        movl    $string, %edi
        cld
        repne   scasb
        not     %ecx
        dec     %ecx
        popl    %edi

        ;; string length is stored in %ecx register

        leave
        ret