Re: Re: GNU Fortran 90?

[tprinceusa at mindspring dot com]

Mike Stump <mrs@windriver.com> wrote:
> > From: jfm2@club-internet.fr
> To: dje@watson.ibm.com
> Cc: toon@moene.indiv.nluug.nl, shebs@apple.com, gcc@gcc.gnu.org
> Date: Wed, 15 Nov 2000 23:34:20 +0100 (CET)

> > 	All of the work may need to be completely restructured to fit into
> > the MMX/SSE vector support that has been added to GCC for x86 instead of
> > having multiple user-level interfaces to the same functionality.

> I don't remember seeing anything in the doc about MMX/SSE in gcc.

:-)  Feel free to write some!

> Could I have some details?

Sure, gcc now implements the annex in the Intel documentation that
describes the C binding layer for SSE.  See their web site for
details, potential applications, sample code and so on.

> Like minimal version,

cvs, top of tree, or, if you prefer 3.0.  :-)

> parms to use and URLs to code who would benefit from use of MX/SSE.

:-) Use your imagination.


I did miss Bernd sneaking it into the tree.  :-(  Congradulation Bernd.

Now, if someone wants to do up an autovectorizing pass to gcc, we'd be
set!  Torbjorn?  Doing anything important?  Think of it, 4 divmods at
once.

SSE is particularly valuable where it avoids the rounding mode changes in (int) casts.  Intel C (Windows only, so far) invokes it automatically in for() loops, but Intel Fortran doesn't.  An opportunity for g77/g95?

It looks like being increasingly important for math functions on P4 models, where the built-in transcendental support is relatively slow.

Tim
tprince@computer.org