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Re: Bad performance (regression) on oopack's Complex test
- From: Paolo Carlini <pcarlini at unitus dot it>
- To: Jan Hubicka <jh at suse dot cz>
- Cc: gcc List <gcc at gcc dot gnu dot org>
- Date: Mon, 27 Jan 2003 21:14:41 +0100
- Subject: Re: Bad performance (regression) on oopack's Complex test
What effect does have -mfpmath=sse switch?
It helps! But, as expected, most noticeably the C test, not the
OOP counterpart (and the Ratio becomes even bigger ;)
Seconds Mflops
Iterations C OOP C OOP Ratio
3.2.1
-----
-O2
Complex 200000 1.6 21.4 981.6 74.8 13.1
-O2 -march=pentium4 -mfpmath=sse
Complex 200000 1.0 19.1 1616.2 84.0 19.2
3.4
---
-O2
Complex 200000 1.6 29.2 993.8 54.8 18.1
-O2 -march=pentium4 -mfpmath=sse
Complex 200000 1.0 27.0 1649.5 59.3 27.8
Thanks,
Paolo