[Lazarus] Convert assembler to Pascal

[Leonardo M. Ramé]

Hi, I'm trying to convert Rijndael encryption method from TPLockBox to
Lazarus/FPC.

While converting the code, I found this routine in Assembler. I'm
wondering if somebody can help me convert this to Pascal?.

Here's the routine:

procedure XorMemPrim(var Mem1;  const Mem2;  Count : Cardinal);
register;
asm
  push esi
  push edi

  mov  esi, eax         //esi = Mem1
  mov  edi, edx         //edi = Mem2

  push ecx              //save byte count
  shr  ecx, 2           //convert to dwords
  jz   @Continue

  cld
@Loop1:                 //xor dwords at a time
  mov  eax, [edi]
  xor  [esi], eax
  add  esi, 4
  add  edi, 4
  dec  ecx
  jnz  @Loop1

@Continue:              //handle remaining bytes (3 or less)
  pop  ecx
  and  ecx, 3
  jz   @Done

@Loop2:                 //xor remaining bytes
  mov  al, [edi]
  xor  [esi], al
  inc  esi
  inc  edi
  dec  ecx
  jnz  @Loop2

@Done:
  pop  edi
  pop  esi
end;

Thanks in advance,
-- 
Leonardo M. Ramé
http://leonardorame.blogspot.com