[MPlayer-dev-eng] ARM and liba52

[Siarhei Siamashka]

Hi,

Currently liba52 is broken for ARM processors which require strict alignment
for accessing memory (ARM9, XScale, ...). AC3 audio playback just produces
noise.

Interestingly enough, the problem was introduced in 2003 (SVN revision 10314),
and it was supposedly a fix for ARM:
http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2003-June/019377.html

I wonder if it was a fix that turned compilation error into runtime failure ;)

Anyway, it should be mentioned that modern ARM cores (such as ARM11) support
unaligned memory access natively. Older cores can emulate unaligned memory
accesses by handling alignment faults in the kernel, but this is very slow.

PS. liba52 uses floating point math which is very slow on old ARM cores
without hardware FPU, so using liba52 on such old cores is not very practical
anyway.

-- 
Best regards,
Siarhei Siamashka