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Re: PPC64 port status

On Mar 31, 2016, at 8:34 AM, Lennart Sorensen <lsorense@csclub.uwaterloo.ca> wrote:

> On Thu, Mar 31, 2016 at 01:18:53AM -0700, Rick Thomas wrote:
>> The altivec instructions and other optimizations speed-up significantly certain kinds of programs on CPUs that can use them.  It would be a shame to loose the optimized versions by dropping back to the lowest common denominator CPU architecture.  Would it be possible to create and support a sub-architecture that provided altivec optimized versions of packages?
> No idea, but certainly in the past i386 did not have sub architectures for
> sse or mmx or anything else.  There were some programs and libraries that
> did have optimizations when they detected such support, and I believe
> that is also true with powerpc already.  libc does do cpu specific
> optimizations at runtime for strcpy and such.
> Any examples of programs where altivec makes a measurable improvement?
> -- 
> Len Sorensen

The main beneficiaries of vector instruction extensions are users of scientific, cryptographic, and audio/visual libraries.  Basically anything that wants to do simple, repetitive operations on long strings of data at memory speed.


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