Well, this is intended to be used on a system where many applications may run concurrently and therefore the need to not denormalise may not be universally shared. Some applications do want to allow computation on denormals in order to get a bit more precision in the result at the expense of a higher cpu cost.
> On 10 Mar 2017, at 10:43, Stefan Stenzel <stefan.sten...@waldorfmusic.de> > wrote: > > How about *not* calling RESTORE_DENORMALS as a courtesy for the rest of the > audio processing chain? > >> On 10 Mar 2017, at 10:28 , Philippe Wicker <pwic...@mac.com> wrote: >> >> Yes, it is done that way in the Apple AudioUnit SDK. The code calls >> DISABLE_DENORMALS at the beginning of the render routine, and >> RESTORE_DENORMALS at the end. Those macros call asm instruction stmxcsr and >> ldmxcsr (in AUBase.cpp: line 53). >>> On 10 Mar 2017, at 10:17, Stefan Stenzel <stefan.sten...@waldorfmusic.de> >>> wrote: >>> >>> I don’t get it - what prevents you from checking/setting DAZ/FTZ in your >>> processing routine? >>> >>> >>>> On 10 Mar 2017, at 10:10 , Richard Dobson <rich...@rwdobson.com> wrote: >>>> >>>> This might not be possible if one is implementing e.g. a plugin to run in >>>> a third-party host - where one does not have full control over the host, >>>> nor indeed of fellow plugins. Whereas adding some ~very~ low level TPDF >>>> dither to a signal should be close to minimum cost. >>>> >>>> Richard Dobson >>>> >>>> On 10/03/2017 08:29, Stefan Stenzel wrote: >>>>> That document is from 2002 - today all these suggestions make little >>>>> sense unless you want your code to run explicitly on a CPU without >>>>> SSE. The best strategy for avoiding denormals is to enforce the >>>>> compiler to use SSE and avoid the FPU, then set the >>>>> Denormals-Are-Zero (DAZ) and Flush-To-Zero (FTZ) flag in the SSE >>>>> status register. >>>>> >>>>> Stefan >>>>> >>>>> >>>> _______________________________________________ >>>> dupswapdrop: music-dsp mailing list >>>> music-dsp@music.columbia.edu >>>> https://lists.columbia.edu/mailman/listinfo/music-dsp >>>> >>> >>> _______________________________________________ >>> dupswapdrop: music-dsp mailing list >>> music-dsp@music.columbia.edu >>> https://lists.columbia.edu/mailman/listinfo/music-dsp >> >> _______________________________________________ >> dupswapdrop: music-dsp mailing list >> music-dsp@music.columbia.edu >> https://lists.columbia.edu/mailman/listinfo/music-dsp > > _______________________________________________ > dupswapdrop: music-dsp mailing list > music-dsp@music.columbia.edu > https://lists.columbia.edu/mailman/listinfo/music-dsp _______________________________________________ dupswapdrop: music-dsp mailing list music-dsp@music.columbia.edu https://lists.columbia.edu/mailman/listinfo/music-dsp
