[LLVMdev] dragonegg svn benchmarks
baldrick at free.fr
Sat Oct 8 12:05:46 PDT 2011
> The Polyhedron 2005 benchmark results for dragonegg svn at r141492
> using FSF gcc 4.6.2svn measured on x86_64-apple-darwin11 are listed below.
> The benchmarks used the optimizaton flags...
> -msse4 -ffast-math -funroll-loops -O3
> in all cases. The use of -fplugin-arg-dragonegg-enable-gcc-optzns to allow
> for autovectorization from the FSF gcc front-end only produces a single run-time
> regression, fatigue, which is PR10892.
thanks for these numbers. I suggest you also try -O4. This does heavier LLVM
optimization when used with -fplugin-arg-dragonegg-enable-gcc-optzns, and seems
to typically result in faster code. You can also use -O6, which does even more
LLVM optimizing, but seems to slow things down (I didn't analyse why yet).
PS: With -fplugin-arg-dragonegg-enable-gcc-optzns the LLVM optimizers are run at
the following levels:
Command line option LLVM optimizers run at
-O1 tiny amount of optimization
-O2 or -O3 -O1
-O4 or -O5 -O2
-O6 or better -O3
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