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--> --> </DEFANGED_STYLE><title>Re: [GRASSLIST:6151] Re: Altivec optimization for
GRASS mo</title></head><body>
<div>Hi</div>
<blockquote type="cite" cite>> Just curious.... has anyone thought
about adding the possibility for<br>
> Altivec acceleration to the source for any of the GRASS
modules?<br>
<br>
<br>
for anyone (like me) who has no idea what Altivec is:<br>
</blockquote>
<blockquote type="cite" cite>
http://en.wikipedia.org/wiki/Altivec<br>
<br>
<br>
<br>
Hamish</blockquote>
<div><br></div>
<div>It's a flag question from compiler (gcc 3.3) but remember, for
example, now Grass use FFTW 2.1.5 library and it's not compatible with
3.0 lib that has Altivec inside.</div>
<div>Now blas and lapack libs are substituted with flag<font
face="Helvetica" color="#000000"> -framework vecLib<font
size="-4"> </font></font></div>
<div>http://developer.apple.com/releasenotes/MacOSX/vecLib.html</div>
<div><br></div>
<div>In the future will be possible to optimize Grass for 64 bit G5
processor. From user reviews on OS X the performances are very good
now with the normal flags. These compiler flags are more compatible
for all OS X versions (10.2, 10.3, 10.4) and all processors (G3, G4
altivec, G5 64 bit)</div>
<div><br></div>
<div><br></div>
<div>There are info about Altivec with a new good version of gcc 4.0
but only for 10.3 at http://hpc.sf.net</div>
<div><br></div>
<div>From site</div>
<blockquote><font face="Optima" color="#660033"><b>GCC 4.0
(auto-vectorizing)</b></font><font face="Optima" color="#000000"><b>
:</b></font></blockquote>
<blockquote><font face="Optima"
color="#000000"><b><br></b></font></blockquote>
<blockquote><font face="Optima" color="#000000">Recently compiled
using source code from the GNU CVS servers,<b> autovect-branch</b> .
This contains beta versions of gfortran (GNU F95) and gcc (GNU C)
compilers that can perform limited auto-vectorization (i.e.
modify code to take advantage of AltiVec, automatically). Use
flags<b> -ftree-vectorize -maltivec</b> to enable that option. For
more information, see</font><font face="Optima"
color="#000066"><b> this webpage</b></font><font face="Optima"
color="#000000"> . Download my binaries, and<b> cd</b> to the
download folder. Then<b> gunzip gcc-vec-bin.tar.gz</b> (if your
browser didn't do so already) and<b> sudo tar -xvf gcc-vec-bin.tar -C
/</b> . It installs everything in<b> /usr/local</b> . You
invoke g95 by typing<b> gfortran</b> . Note that you may need to add
the flag<b> -lstdc++</b> for getting it recognize some of the
unimplemented standard functions. You will also need to have
Apple's Developer Tools installed. They are included on a
separate CD in the retail version of OS X and also available as a free
download from</font><font face="Optima" color="#000066"><b> Apple's
Developer Site</b></font><font face="Optima" color="#000000"> .
Please install the most current version of Developer
Tools.</font></blockquote>
<blockquote><font face="Optima"
color="#000000"><br></font></blockquote>
<div><br></div>
<div><br></div>
<div>Bye</div>
<div><br></div>
<x-sigsep><pre>--
</pre></x-sigsep>
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