gcc will become the best optimizing x86 compiler

[Agner Fog]

Basile STARYNKEVITCH wrote:
 >At last, at the recent (july 2008) GCC summit, someone (sorry I forgot 
who, probably someone from SuSE)
 > proposed in a BOFS to have architecture and machine specific 
hand-tuned (or even hand-written assembly) low
 > level libraries for such basic things as memset etc..

That's exactly what I meant. The most important memory, string and math 
functions should use hand-tuned assembly with CPU dispatching for the 
latest instruction sets. My experiments show that the speed can be 
improved by a factor 3 - 10 for unaligned memcpy on Intel processors 
(http://www.agner.org/optimize/optimizing_cpp.pdf page 12).

There will be more hand-tuning work to do when the 256-bit YMM registes 
become available in a few years - and more to gain in speed.