29 Jan
2011
29 Jan
'11
1:46 p.m.
On Sat, Jan 29, 2011 at 01:22:10PM +0100, Philipp Überbacher wrote:
I thought that log2() might use a different routine if
the argument is a
power of 2. I guess that even if it does it's nothing to rely on because
another libm implementation might not do the same thing.
There are very good reasons why math routines don't do such things.
Why did you choose 1e-6 specifically?
It does the job. 1e-6f will also work for single precision.
... Without optimisation the output is quite
different, but beginning with -O2 the machine code appears all the same.
That could well be completely different on an another CPU and compiler,
and even more so if tested ***in context***. Such tests are really
pointless, in particular if you consider the actual use of this code.
It isn't executed 100 times for each audio sample.
If the optimised code really is the same is it worth
it to use funky bit
shifting operations?
There's nothing funky about them, they are part of C and C++.
Ciao,
--
FA
There are three of them, and Alleline.