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Re: C Optimization, Pentium 4, 4 May 2004, tree-ssa/3.5/3.4/icc

Diego Novillo wrote: 
Ah, OK.  Thanks.  You are positive that tree-ssa gets the right result
on alma, eh?  I wonder if we are hitting a micro-optimization of some
kind.  Can I get the source code for these tests somewhere?

When I compile with -DVERIFY, the alma produces identical output when generated by tree-ssa and 3.4. Of course, the I/O time dominates the performance profile, so tree-ssa is only slightly faster with VERIFY defined. It could be, I suppose, the tree-ssa and Intel optimize away most of the code when nothing is output. I'll look into it...

--
Scott Robert Ladd
Coyote Gulch Productions (http://www.coyotegulch.com)
Software Invention for High-Performance Computing

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