flac dev - Feb 2012 - Please test new endian stuff

Hi all,

I've just pushed some changes to git repo that changes the way endian
swapping is done. In particular it does:

  a) On Linux, use the bswap_*() intrinsic.

  b) On Windows _byteswap_*() intrinsic.

  c) Falls back to a macro for everything else.

I've tested this on 64 bit little endian Linux (x86_64) and 32 bit
bug endian Linux (powerpc).

Needs testing elsewhere.

Cheers,
Erik
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/

Mac OS X also provides routines for byteswapping- for this case CFSwapInt32()
which calls through to __DARWIN_OSSwapInt32()- but I don't know if they
would be any more efficient than the macro version.

Stephen

On Feb 5, 2012, at 4:41 AM, Erik de Castro Lopo wrote:
> _byteswap_
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On 5 February 2012 01:41, Erik de Castro Lopo <mle+la at mega-nerd.com>
wrote:
> ?a) On Linux, use the bswap_*() intrinsic.
FWIW, Both Apple llvm-gcc 4.2.1 and Apple clang 3.0 support
__builtin_bswap32() At least on XCode 4.2. It compiles to the bswap
instruction.

 -r

Ralph Giles wrote:
> On 5 February 2012 01:41, Erik de Castro Lopo <mle+la at
mega-nerd.com> wrote:
> 
> > ?a) On Linux, use the bswap_*() intrinsic.
> 
> FWIW, Both Apple llvm-gcc 4.2.1 and Apple clang 3.0 support
> __builtin_bswap32() At least on XCode 4.2. It compiles to the bswap
> instruction.
Ok, I have an M4 macro to detect the presence of __builtin_bswap32()
and I've tested it on BE and LE linux.

The scheme now is:

  a) Use __builtin_bswap32() where present (should be all versions of
     GCC and Clang).

  b) Use _byteswap_ulong() under MSVC.

  c) Use bwap32() if <byteswap.h> is present.

  d) Fall back to a macro.

Erik
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/