[FFmpeg-devel] [PATCH] ARM: NEON optimised {put, avg}_h264_chroma_mc[48]

Måns Rullgård mans
Mon Aug 25 13:32:53 CEST 2008

"Ian Caulfield" <ian.caulfield at gmail.com> writes:

> 2008/8/25 M?ns Rullg?rd <mans at mansr.com>:
>> "Ian Caulfield" <ian.caulfield at gmail.com> writes:
>>> 2008/8/25 Mans Rullgard <mans at mansr.com>
>>>> +        vld1.64         {d4, d5}, [r1], r4
>>> Can you guarantee any kind of alignment on the address in r1? If so,
>>> potentially better performance can be achieved by specifying the
>>> alignment in the opcode...
>> I know, and I've specified it everywhere I know of a guaranteed
>> alignment.  I don't know which line you're quoting, but if it's the
>> source address for an h264_chroma_mc function, there are no promises.
> Fair enough - hadn't looked at your other patches.

If you see anything else that looks suboptimal, please tell.

>> Do you have something ARMv7 based?
> No, but I'm quite familiar with the Neon units on the Cortex-A8 and -A9.

The A9 hasn't even made it to silicon yet.  Do you know something the
rest of us don't?

M?ns Rullg?rd
mans at mansr.com

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