sincos?

[Steve Kargl]

On Wed, Jun 26, 2013 at 04:45:34PM -0700, enh wrote:
> i'm a recent lurker on this list; i've inherited Android's C library, and
> among other things i'm trying to track FreeBSD's lib/msun much more closely
> than we have traditionally.
> 
> i was just reminded of the existence of a change submitted to us (Android)
> a while back that adds a sincos/sincosf implementation cobbled together
> from your s_sin.c/s_sinf.c and s_cos.c/s_cosf.c implementations:
> https://android-review.googlesource.com/#/c/47585/<https://android-review.googlesource.com/#/c/47585/1>
> 

A quick glance at the code shows that the android project has
slapped its Copyright on fdlibm code.  I suspect that you'll
want to restore proper attribution to Sun Microsystems.

> the submitter (Intel) rightly points out that at the moment GCC carefully
> optimizes paired sin/cos calls into a sincos call which we deoptimize back
> into separate sin/cos calls. i personally don't want to take on maintenance
> of this, but i would be happy to include you guys' sincos implementation if
> you had one. is there a reason you don't have one?

I haven't submitted the versions of sincos[fl], which I've
developed over the last year or so, yet.  First, I need to
redo some testing.  Second, I need to convince Bruce that
the implementation would be a nice addition to libm. 

-- 
Steve