On Wed, 16 Sep 2009 18:47:42 +0530 (IST), Giridhar Tammana <giri_tamm...@yahoo.co.in> wrote: > On NEON alignment, > There can be lot improvement in performance if buffers are aligned. Also > interleaving stores would not throttle the store buffer. > Maximum outstanding stores can be 8 dregisters.
IOW, we can spare one cycle per load or store with appropriate alignment. That's what I said. > There are no intrinsic for specifying alignment. I do not think anyone proposed to use intrinsic functions. This patch uses in-line assembly. Plain assembly should be used for further optimization (I'd rather not unroll in-line assembly). > So to get maximum memory bandwidth one has to align buffers and also use > special instructions specifiers. I think we cannot align buffers at least in some cases. Namely the X and XY cases, some buffers are read with one byte offset... so at least one if not both of the read must be unaligned. That's why I'm asking if we can assume alignment in any case at all. The SVN changelog mentions some aligned memory allocation, but I have not looked at what that actually was about. -- Rémi Denis-Courmont ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ Libmpeg2-devel mailing list Libmpeg2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmpeg2-devel
