|Re: [eigen] sse asin implementation|
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] sse asin implementation
- From: Rohit Garg <rpg.314@xxxxxxxxx>
- Date: Tue, 31 Mar 2009 22:08:15 +0530
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For general exponentiation, I think a cheap and easy route would be
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.
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
On Tue, Mar 31, 2009 at 9:47 PM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:
> 2009/3/31 Rohit Garg <rpg.314@xxxxxxxxx>:
>>> As I said, there's at least one very useful function that's not yet
>>> vectorized: pow.
>> You are looking towards Packet4f pow(Packet4f a, Packet4f b) right?
> Yes, exactly. Actually, I think that in most cases b would be just a
> scalar, however if you implement the above, we'll get that by passing
> a constant packet as b.
> If it makes things faster / easier, I'd say don't hesitate to go for
> Packet4f pow(Packet4f a, float b)
> instead. This would then be called when the user does
> result_vector = vector.cwise().pow(b); // where b is a float.
>> Rohit Garg
>> Senior Undergraduate
>> Department of Physics
>> Indian Institute of Technology
Department of Physics
Indian Institute of Technology