Re: git: c6c6e67d83c2 - main - audio/flac: don't disable VSX on powerpc64le

On 21-11-01 19:28:20, Christian Weisgerber wrote:
> Matthias Andree:
> 
> > > --enable-sse simply adds "-msse2" to the compiler flags.
> > > 
> > > On amd64, this is a nop, since SSE2 is part of the amd64 architecture.
> > > On i386, it generates code that won't run on older CPUs that don't
> > > support SSE2.
> > 
> > Yeah - do we care? SSE2 has come of age in most legislations :-)
> 
> So has amd64.  The only reason to run i386 is on machines that don't
> support amd64, e.g. old Soekris [45]xxx and the like.
> 
> Note that flac has assembly optimizations for various SSE levels
> that are properly enabled at runtime based on CPUID.  You're getting
> all that on modern CPUs.

On POWER disabling VSX actually disables some code, eg.:
https://github.com/xiph/flac/blob/master/src/libFLAC/lpc_intrin_vsx.c#L39
https://github.com/xiph/flac/blob/master/src/libFLAC/include/private/lpc.h#L94
https://github.com/xiph/flac/blob/master/src/libFLAC/stream_encoder.c#L888

This is a valid reason not to disable VSX if the baseline already includes VSX (which is the case on powerpc64le).

> 
> -- 
> Christian "naddy" Weisgerber                          naddy@mips.inka.de