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25% slower than GNU g++?


My test is just to multiply two 300x300 complex<double> matrices.  I am curious
if the slowdown I see is normal or abnormal?

GNU compiler:
csdsun1:~/C $ g++ -O4 matrix_g++.C 
csdsun1:~/C $ time a.out
real    0m14.884s
user    0m14.710s
sys     0m0.130s
csdsun1:~/C $ g++ -v
Reading specs from
/opt/depot/gcc-2.8.1/lib/gcc-lib/sparc-sun-solaris2.6/2.8.1/specs
gcc version 2.8.1


Solaris CC compiler:
csdsun1:~/C $ CC -O4 matrix.C -lcomplex
csdsun1:~/C $ time a.out
real    0m28.110s
user    0m27.930s
sys     0m0.140s
csdsun1:~/C $ CC -V
CC: WorkShop Compilers 4.2 30 Oct 1996 C++ 4.2


ECGS compiler:
csdsun1:~/C $ time a.out
real    0m18.965s
user    0m18.810s
sys     0m0.120s
csdsun1:~/C $ g++ -v
Reading specs from
/home/post/opt/lib/gcc-lib/sparc-sun-solaris2.6/egcs-2.91.60/specs
gcc version egcs-2.91.60 19981201 (egcs-1.1.1 release)


I would be happy to work with you to resolve this if I can help.  My problems
rely heavily on complex numbers!

Best regards,
--
John T. Post
Applied Research Laboratories
The University of Texas at Austin
Austin, TX 78713-8029
512-835-3791 voice
512-835-3259 fax
post@arlut.utexas.edu


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