On Sun, Apr 26, 2009 at 12:52:00PM -0400, Neal Becker wrote:
I saw this on gcc devel ML:
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On Thu, 23 Apr 2009, David Ronis wrote:
> >From the info pages it seems that the new optimizations,
> -floop-interchange, -floop-strip-mine, and -floop-block, are NOT turned
> on when -O3 is specified. Is this correct and if so, why aren't they?
Because the behavior of -O3 must not depend on whether optional libraries
are linked into GCC, and we did not decide to make PPL and CLooG required
to build GCC, so -O3 cannot enable any optimizations using optional
libraries.
Joseph S. Myers
joseph(a)codesourcery.com
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Does our gcc-4.4 have these optional libs?
Yes, it does (though, I've patched it a little bit, so that cc1/cc1plus/f951
etc. aren't unconditionally linked against -lcloog -lppl -lppl_c -lm -lstdc++ -lgmpxx
libs cloog/ppl depend on, but instead dlopens libcloog.so.0 when the
graphite optimizations are used (-floop-block, -floop-interchange,
-floop-strip-mine, -fgraphite-identity or -fgraphite)).
Jakub