[PD] Lost at compilig cyclone ;-((((

[Frank Barknecht]

Hallo,
Krzysztof Czaja hat gesagt: // Krzysztof Czaja wrote:

> while without "-O6" it works ok.  The bottom line is, that I do not
> know the rules (if there are any).

This one was posted by Simon Jenkins last week on linux-audio-dev: 

	I (re)discovered the following branch-free method a while ago:

	/* branch-free denormal killer (slightly blunt) */

	inline float FlushToZero( volatile float f )
	{
	  f += 9.8607615E-32f;
	  return f - 9.8607615E-32f;
	}

	/* end */

	The people who discovered it first call this method "Elimination
	by Quantification".

	Its slightly blunt because it damages the precision of extremely
	low but not yet denormal numbers: Anything of magnitude < 2 **
	-103 loses one bit of precision for each binary order of magnitude
	it is below that number.  (This means that denormal numbers lose
	/all/ of their precision and become zero).

	Simon Jenkins
	(Bristol, UK)

He later added: 

	The reason its an inline function rather than a drop-in
	replacement macro is because casting macro arguments to volatile
	wasn't having the desired effect on the optimiser, whereas this
	does.

Maybe it's an alternative to consider in some cases? 

Ciao
-- 
 Frank Barknecht                               _ ______footils.org__