[LAD] Denormals, Re: Routing signals in mixer (Ardour, Qtractor)

[Tim Goetze]

[James Morris]

>On 15 July 2010 18:23, Harry Van Haaren <harryhaaren at gmail.com> wrote:
>> http://en.wikipedia.org/wiki/Denormal_number
>>
>> A nice "quick" fix for these is:
>> if ( number < 0.000000001)
>>       number = 0.0;
>>
>> ;-)
>
>Don't forget about negative numbers ;-)
>
>n = ((n > 0.0 && n < 0.000000001) || (n < 0.0 && n > -0.000000001)) ? 0.0 : n;

I can't seem to remember the most sensible numeric limit for this 
branching variant of denormal removal -- besides, it obviously depends 
on the context in question and the use of floats versus doubles (as 
does the use of fabsf versus fabs in what follows) -- but I am quite 
positive that the following line, which replaces the above one, is not 
only easier to read, but also stands a good chance of executing 
quicker on most contemporary CPUs due to the elimination of at least 
one branching instruction:

	n = fabs(n) < 1e-9 ? 0 : n; 

Cheers, Tim