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Re: New GCC releases comparison and comparison of GCC4.4 and LLVM2.5 on SPEC2000


Vladimir Makarov wrote:
Chris Lattner wrote:
2. You change two variables in your configurations: micro architecture and pointer size. Would you be willing to run x86-32 Core i7 numbers as well? LLVM in particular is completely untuned for the (really old and quirky) "netburst" architecture, but I'm interested to see how it runs for you on more modern Core i7 or Core2 processors in 32-bit mode.

I used the same processor (P4) and options for x86 as for the GCC release comparison.
I was wrong here GCC-LLVM comparison does not use -mtune=pentium4 as it was used for GCC releases. So default x86 tunings for the compilers were used for the 32-bit comparison. Still the results might look different on Core i7.

Sorry, I missed to mention that I used an additional option -mpc64 for 32-bit GCC4.4. It is not possible to generate SPECFP2000 expected results by GCC4.4 without this option. LLVM does not support this option. And this option can significantly improve the performance. So 32-bit comparison of SPECFP2000 should be taken with a grain of salt.

I've just corrected page http://vmakarov.fedorapeople.org/spec/llvmgcc32.html by adding these comments.



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