Faster hashing

1000000 Hashes
```
SM Timing
-----------
SizeT hash 	      1	00.061367	(00.061367 +- 00.000000)	[00.061367,00.061367]
String hash	      1	01.651815	(01.651815 +- 00.000000)	[01.651815,01.651815]
```
Yes good point. I can add that which should save two more cycles. We are
already a good amount faster than two other approaches which I tried last
night and which claimed to be 'the fastest'.
On Aug 15, 2014 6:52 AM, "tcies" <notifications@github.com> wrote:

> In sm_common/include/sm/hash_id.hpp:
>
> > @@ -67,6 +80,21 @@ class HashId {
> >    }
> >
> >    /**
> > +   * Rehashes the 128 bit hash to a 32/64 bit hash that can be used in STL
> > +   * containers. This means that we will get collisions on the buckets, which
> > +   * is fine since we can disambiguate the actual hashes using operator==.
> > +   * So this does not increase the probability of ID collision.
> > +   */
> > +  inline size_t hashToSizeT() const {
>
> Couldn't we also provide a flavor without the magic number multiplication
> for applications that are confident that the hashid they use comes from a
> uniform enough distribution?
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/ethz-asl/Schweizer-Messer/pull/98/files#r16280201>.
>