On 07.10.12 10:25, Georg-Johann Lay wrote:
> Are such calls "allowed" in avr-libc provided
>
> - The special interface is documented in libgcc sources and mentions
> that avr-libc makes use of the special interface
>
> - The functions with their special interface are documented, e.g. in
> the GCC wiki
Well, that's how I would do it in a project of mine, FWIW.
> The question is for code that is not yet part of avr-libc, namely the
> upcoming fixed-point support; it's not about optimizing code that's
> already there.
>
> Sean said that CORDIC shows bad rounding for asin, for example.
>
> I played around with a home-brew asin approach that has no rounding
> issues. The performance of the implementation can be improved if
> knowledge of libgcc is used.
Holy cow, the approach is fine, I figure, just from the perspectives of
consistent code behaviour and reuse. Add performance improvements and
your case is irresistible, I reckon.
I've only tried basic CORDIC to produce sin and cos. I didn't know that
asin was feasible with the method.
Erik
--
The tools we use have a profound and devious influence on our thinking
habits, and therefore on our thinking abilities.
-Edsgar W. Dijkstra
_______________________________________________
AVR-GCC-list mailing list
AVR-GCC-list@nongnu.org
https://lists.nongnu.org/mailman/listinfo/avr-gcc-list
