search for: _low_accuracy_

Displaying 2 results from an estimated 2 matches for "_low_accuracy_".

2003 May 23
0
_LOW_ACCURACY_ good enough?
I spent a fair amount of time optimizing tremor for the PS2, mostly by using dual-pipe multiplies in the X[N]PRODnn and the window apply code. Then, just for kicks, I re-enabled _LOW_ACCURACY_ and lo and behold it was still substantially faster. I also got some gains out of tremor by changing the longs in cookbook and sharedbook to ogg_int32_t's like I did for vorbis. I think _LOW_ACCURACY_ is a win mostly because I'm entirely cache-bound in mdct_backward. But my question is,...
2003 May 20
2
mdct_backward with fused muladd?
Can anybody point me at any resources that would explain how to optimize mdct_backward for a cpu with a fused multiply-accumute unit? >From what I understand from responses to my older postings, Tremor's mdct_backward could be rewritten to take advantage of a muladd. My target machine can do either two-wide 32x32 + Accum(64) -> Accum(64) integer muladd or eight-wide 16x16 + Accum(32)