[MPlayer-dev-eng] ARM and liba52

[Uoti Urpala]

On Thu, 2008-05-01 at 13:05 +0300, Siarhei Siamashka wrote:
> On Monday 28 April 2008, Siarhei Siamashka wrote:
> > 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.
> 
> Ping.
> 
> Can anybody consider reverting r10314 change? Or alternatively you can try to
> use the attached patch. Anyway, some kind of action needs to be taken to fix
> this breakage.

So this problem only occurs on cores where the code is "not very
practical" anyway?

Reverting it should be OK though - gcc seems to generate the same code
for both versions on x86 where unaligned access works, so there should
be little reason to use the raw unaligned access code except possibly to
force unaligned access on a target which may support it but isn't
guaranteed to.

> Also I strongly suspect that r10490 was a proper fix for that ARM
> compilation issue with gcc 2.95 that r10314 tried to address but introduced
> a bigger problem instead.

It doesn't change the same code except changing "inline" to
"always_inline" so I don't see how it could be a fix for the same
compilation issue.