On Sat, Nov 13, 2010 at 02:57:44PM +0000, Folderol wrote: > Paul Davis <[email protected]> wrote: > > > there's an awful lot of math for which a modern processor can compute > > the answer faster than it can look it up. this is one such example (as > > fons noted), but there are many others. this started changing about 8 > > years ago, and its only gotten more true since then. > > Oh dear. I didn't realise I was so far out of date :(
It's absolutely true. Note that the calculation I posted earlier runs entirely on the FP processor, and two variables, q and d, will probably only exist there and never be written to memory. If it takes any time at all, the CPU can meanwhile do something else, such as getting the pointers to the audio data it will need later. Using a LUT will mean the CPU has to do all the work, which includes getting the base pointer and calculating the required offset(s). Ciao, -- FA There are three of them, and Alleline. _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/listinfo/linux-audio-dev
