Re: hashed_maps

[Matthew Heaney <matthewjheaney@earthlink.net>]

Robert A Duff <bobduff@shell01.TheWorld.com> writes:

> Addresses usually have the low 2 or 3 bits equal to zero, because of
> alignment concerns.  So use Address_To_Integer and shift right 3 bits.
> Then mod by the size of the hash table, or take some high-order bits
> and add them into the low-order bits.

In the case of the standard hashed containers, I'm not sure you would
need to bother, since the mod'ing is done internally by the container.

I think you'd only need to right shift if you were to throw away upper
bits, say because System.Storage_Elements.Integer_Address has a wider
range than Ada.Containers.Hash_Type.