[vlc-devel] commit: contrib: turn off Thumb ISA for libavcodec and libmad ( Rémi Denis-Courmont )

[Rafaël Carré]

On Sat, 29 Aug 2009 22:06:38 +0300
"Rémi Denis-Courmont" <remi at remlab.net> wrote:

> I guess avcodec uses fancy ASM instructions outside of Thumb-2.

You can't use inline asm when asking GCC to build thumb because you
don't know if it will use ARM or THUMB instruction set for a specific
function.

A solution would be to build the files containing inline ARM asm with
-mno-thumb -mthumb-interwork but you'd have to check every file

Last but not least: thumb is quite limited and considered slower than
ARM code (note thumb-2 appears to be generally faster than thumb) so
it's not advised for multimedia routines especially when you have loads
of memory available and code size doesn't matter that much.

-- 
Rafaël Carré
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