Arrays dinámicos en memoria

[eliash]

Me encantaría hacerlo pero...

procedure DynArraySetLength(var a: Pointer; typeInfo: Pointer; dimCnt: Longint; lengthVec: PLongint);
var
  i: Integer;
  newLength, oldLength, minLength: Longint;
  elSize: Longint;
  neededSize: Longint;
  p, pp: Pointer;
begin
  p := a;

  // Fetch the new length of the array in this dimension, and the old length
  newLength := PLongint(lengthVec)^;
  if newLength <= 0 then
  begin
    if newLength < 0 then
      Error(reRangeError);
    DynArrayClear(a, typeInfo);
    exit;
  end;

  oldLength := 0;
  if p <> nil then
  begin
    Dec(PLongint(p));
    oldLength := PLongint(p)^;
    Dec(PLongint(p));
  end;

  // Calculate the needed size of the heap object
  Inc(PChar(typeInfo), Length(PDynArrayTypeInfo(typeInfo).name));
  elSize := PDynArrayTypeInfo(typeInfo).elSize;
  if PDynArrayTypeInfo(typeInfo).elType <> nil then
    typeInfo := PDynArrayTypeInfo(typeInfo).elType^
  else
    typeInfo := nil;
  neededSize := newLength*elSize;
  if neededSize div newLength <> elSize then
    Error(reRangeError);
  Inc(neededSize, Sizeof(Longint)*2);

  // If the heap object isn't shared (ref count = 1), just resize it. Otherwise, we make a copy
  if (p = nil) or (PLongint(p)^ = 1) then
  begin
    pp := p;
    if (newLength < oldLength) and (typeInfo <> nil) then
      FinalizeArray(PChar(p) + Sizeof(Longint)*2 + newLength*elSize, typeInfo, oldLength - newLength);
    ReallocMem(pp, neededSize);
    p := pp;
  end
  else
  begin
    Dec(PLongint(p)^);
    GetMem(p, neededSize);
    minLength := oldLength;
    if minLength > newLength then
      minLength := newLength;
    if typeInfo <> nil then
    begin
      FillChar((PChar(p) + Sizeof(Longint)*2)^, minLength*elSize, 0);
      CopyArray(PChar(p) + Sizeof(Longint)*2, a, typeInfo, minLength)
    end
    else
      Move(PChar(a)^, (PChar(p) + Sizeof(Longint)*2)^, minLength*elSize);
  end;

  // The heap object will now have a ref count of 1 and the new length
  PLongint(p)^ := 1;
  Inc(PLongint(p));
  PLongint(p)^ := newLength;
  Inc(PLongint(p));

  // Set the new memory to all zero bits
  FillChar((PChar(p) + elSize * oldLength)^, elSize * (newLength - oldLength), 0);

  // Take care of the inner dimensions, if any
  if dimCnt > 1 then
  begin
    Inc(lengthVec);
    Dec(dimCnt);
    for i := 0 to newLength-1 do
      DynArraySetLength(PPointerArray(p)[i], typeInfo, dimCnt, lengthVec);
  end;
  a := p;
end;

procedure _DynArraySetLength;
asm
{       PROCEDURE _DynArraySetLength(var a: dynarray; typeInfo: PDynArrayTypeInfo; dimCnt: Longint; lengthVec: ^Longint) }
{     ->EAX     Pointer to dynamic array (= pointer to pointer to heap object) }
{       EDX     Pointer to type info for the dynamic array                     }
{       ECX     number of dimensions                                           }
{       [ESP+4] dimensions                                                     }
        PUSH    ESP
        ADD     dword ptr [ESP],4
        CALL    DynArraySetLength
end;

Ésto me sobrepasa ampliamente. De hecho no se ni por donde cogerlo :|
Si no es mucha molestia me gustaría saber, por lo menos, cuanto espacio reserva un array dinámico en memoria...
¿Alguien lo sabe?