Re: sup****ting header-less blocks in memory allocators...

On Oct 2, 8:29=A0pm, "Chris M. Thomasson" <n...@[EMAIL PROTECTED]
> wrote:

> But how could I efficiently intermingle large blocks and small blocks
fro=
m a
> single reserved memory pool?

In one of my programs I used following scheme:

template<typename derived_t>
class object_t
{
  static void* operator new (size_t sz)
  {
    // derived_t must be most derived type
    assert(sz =3D=3D sizeof(derived_t));
    // resolved at compile-time
    if (sizeof(derived_t) <=3D 4)
      return thread().fixed_alloc_4.alloc();
    else if (sizeof(derived_t) <=3D 8)
      return thread().fixed_alloc_8.alloc();
    else if (sizeof(derived_t) <=3D 16)
      return thread().fixed_alloc_8.alloc();
    else if (sizeof(derived_t) <=3D 32)
      return thread().fixed_alloc_8.alloc();
    [...]
    else
      return ::malloc(sizeof(derived_t));
  }

  static void operator delete (void* p)
  {
    // resolved at compile-time
    if (sizeof(derived_t) <=3D 4)
      thread().fixed_alloc_4.free(p);
    else if (sizeof(derived_t) <=3D 8)
      thread().fixed_alloc_8.free(p);
    else if (sizeof(derived_t) <=3D 16)
      thread().fixed_alloc_8.free(p);
    else if (sizeof(derived_t) <=3D 32)
      thread().fixed_alloc_8.free(p);
    [...]
    else
      ::free(p);
  }
};


Dmitriy V'jukov