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Re: povray: Revised numbers
On Sat, 17 Jan 2004, Jan Hubicka wrote:
> > Here are revised numbers for my povray test, based on comments both
> > public and private:
> > compile benchmark
> > time time
> > -------- ---------
> > gcc mainline 1:43 7:59
> > w/ -mfpmath=sse 1:46 6:30
> > gcc tree-ssa 1:46 7:35
> > w/ -mfpmath=sse ** SEG fault **
> > icc 8.0 1:53 5:50
> Thanks for testing.
> If you have code where -mfpmath=sse lose considerably on mainline
> (3.3 branch had very fresh SSA implementation and lacked P4 tunning), I
> would be interested in seeing it.
As can Scott, so can I ;) Here are some benchmarks for my favorite POOMA
based application. For current 3.3, 3.4 and Intel 8.0 (tree-ssa ICEs).
For a fair comparison, I dropped __attribute__((leafify)) in one round of
testing, as I cannot hack Intel 8.0 for my needs.
Compiler flags are -O2 -funroll-loops -ffast-math -march=athlon for gcc
and -O2 -ip for icc. Tests are done on an Athlon 1GHz with 1GB ram.
gcc 3.3 is 3.3.3 20040112, gcc 3.4 is 3.4.0 20040114, icc 8.0 is build
compile time run time binary size (static, stripped)
gcc3.3 6m57s 1m24s 2877232
8m23s 0m34s 2963408 __attribute__((leafify))
gcc3.4 3m41s 1m10s 2584088
5m04s 0m39s 2682520 __attribute__((leafify))
icc8.0 12m41s 0m42s 5046476
So what one can clearly see, Intel 8.0 looses all the way down in compilation
speed and binary size, but is a lot better in runtime than plain gcc. And
it should be clear, why I'm still maintaining the leafify attribute
The leafify test also shows that mainline/3.4 has somewhat regressed in
speed compared to 3.3 - performance I expect to get back after rtlopt
been merged. Together with the new parser and improved ISO compliance I'm
quite happy with 3.4.
I'd love to test tree-ssa, but that doesn't build my application at the
moment (and I don't have the leafify attribute fixed wrt the latest
cgraph changes yet).