Re: [eigen] sse asin implementation

[ Thread Index | Date Index | More Archives ]

2009/3/31 Rohit Garg <rpg.314@xxxxxxxxx>:
> For general exponentiation, I think a cheap and easy route would be
> just exp(b*log(a))
> I looked at the cephes library implementation of pow and they do a lot
> of hacks just to get 3 bits of precision. In the use case that you
> have cited, I think it's better to just have the above implementation.
> It is certainly good enough for the -ffast-math case.

OK, seems sensible. But I thought the main justification for a simd
pow() would be performance, that it could be faster than the above
formula. If that's not the case then sure, I agree with you.

> BTW, what do you think of enabling the fast math paths in eigen when
> just -ffast-math is supplied to gcc. It can be detected by the
> __FAST_MATH__ macro.

That seems like a good idea! Let's see what Gael thinks.


Mail converted by MHonArc 2.6.19+