[FFmpeg-devel] [PATCH] Make DECLARE_ALIGNED macros take array specifiers as separate argument

Måns Rullgård mans
Tue Oct 27 21:35:47 CET 2009


Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:

> On Tue, Oct 27, 2009 at 07:25:51PM +0000, M?ns Rullg?rd wrote:
>> Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:
>> > Don't worry, I wasn't going to object on that grounds, I just considered
>> > it reason enough to ask if there's an alternative.
>> > Could you give us an example for the syntax the TI compiler needs?
>> > In principle I guess it's ok, though checking if someone has a better
>> > idea can't hurt I'd think...
>> 
>> The following macros will need to be added in appropriate places:
>> 
>> #define AV_PRAGMA(s) _Pragma(#s)
>> 
>> #define DECLARE_ALIGNED(n,t,v,...)                  \
>>     AV_PRAGMA(DATA_ALIGN(v,n))                      \
>>     t v __VA_ARGS__ __attribute__((aligned(n)))
>> #define DECLARE_ASM_CONST(n,t,v,...)                \
>>     AV_PRAGMA(DATA_ALIGN(v,n))                      \
>>     static const t v __VA_ARGS__ __attribute__((aligned(n)))
>> 
>> #define LOCAL_ALIGNED(a, t, v, s, ...)                          \
>>     uint8_t la_##v[sizeof(t s __VA_ARGS__) + (a)];              \
>>     t (*v) __VA_ARGS__ = (void *)FFALIGN((uintptr_t)la_##v, a)
>> 
>> The last one will have to be used for local vars needing alignment.
>> This is needed with gcc too on some platforms.
>
> That's the only thing it is needed for?

The other macros are needed for non-stack variables.

> I thought the conclusion was to get rid of stack variables needing
> alignment...

Good luck with that.

-- 
M?ns Rullg?rd
mans at mansr.com



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