rdoff/test/rdtlib.asm

   1         ;; library functions for rdtmain - test of rdx linking and execution
   2
   3         ;; library function = _strcmp, defined as in C
   4
   5 [SECTION .text]
   6 [BITS 32]
   7
   8 [GLOBAL _strcmp]
   9 _strcmp:
  10         push ebp
  11         mov ebp,esp
  12
  13         ;; ebp+8 = first paramater, ebp+12 = second
  14
  15         mov esi,[ebp+8]
  16         mov edi,[ebp+12]
  17
  18 .loop:
  19         mov cl,byte [esi]
  20         mov dl,byte [edi]
  21         cmp cl,dl
  22         jb .below
  23         ja .above
  24         or cl,cl
  25         jz .match
  26         inc esi
  27         inc edi
  28         jmp .loop
  29
  30 .below:
  31         mov eax,-1
  32         pop ebp
  33         ret
  34
  35 .above:
  36         mov eax,1
  37         pop ebp
  38         ret
  39
  40 .match:
  41         xor eax,eax
  42         pop ebp
  43         ret
  44
  45 [SECTION .data]
  46 [GLOBAL _message]
  47
  48 _message:       db 'hello',0