"Richard Cavell" <ri***********@mail.com> wrote in message
news:d0**********@nnrp.waia.asn.au...
Hi,
Many processors have some kind of facility for working on multiple data at
once (MMX, SIMD, SSE2, Altivec, Velocity Engine, etc). What's the state
of the art with regards trying to use these with C/C++? How does one
present data to the compiler so that the compiler might be able to invoke
the vector unit?
I'm not sure what you mean bvy a "vector unit"...? Are you referring to
multiple processors on one computer? If so, the OS takes care of when/if
those are used, usually. But if you write code that uses threads, then the
computer is likely to make use of both processors when two threads are
running concurrently.
However, hardware issues and threads are not topical to this newsgroup,
which discusses C++ language issues (since standard C++ does not specify
anything (at least not yet) about threading models). I don't know if
there's a newsgroup that does discuss general multi-processor questions, but
you could search on groups.google.com, or find a newsgroup that discusses
the particular OS or hardware you're interested in.
-Howard