From mboxrd@z Thu Jan  1 00:00:00 1970
From: Burkhard Militzer <militzer@llnl.gov>
To: <gcc@gcc.gnu.org>
Subject: Do we get the other 15% performance back too?
Date: Mon, 26 Aug 2002 09:43:00 -0000
Message-id: <Pine.LNX.4.33.0208260923090.3598-100000@dresden.llnl.gov>
X-SW-Source: 2002-08/msg01612.html

Hello,

As a fan of the C++ gnu compiler project, I would like to congratulate the 
gurus on the recent performance increase probably coming from corrections 
in the prefetch routines. My benchmark shows

Processor/OS         Compiler/options             Time(sec)
Pentium 4 1.7Ghz     pgCC -O3 -fast -Minline=3/4   8.27  
Pentium 4 1.7Ghz     gnu g++ -O3 (2.95.2)          8.62  <-- fastest
Pentium 4 1.7Ghz     Intel icpc 5.0 -O3            8.65  
Pentium 4 1.7Ghz     gnu g++ -O3 (2.95.3)         10.94   
Pentium 4 1.7Ghz     gnu g++ -O3 (3.2)            11.30  <-- new
Pentium 4 1.7Ghz     gnu g++ -O3 (3.01)           15.09  <-- previous

The improvement from 3.01 to 3.2 are significant but it their a way of 
somehow getting the performance of 2.95.2 back?

Anyway, great work! Thanks a lot,

Burkhard Militzer

For comparison:
      						    
DEC Alpha 1GHz       KCC kcc3.4d -O3               5.2   
DEC Alpha 667MHz     KCC kcc3.4g2 -O3              8.4   
DEC Alpha 667MHz     g++ -O3 (2.96?)              10.3   
DEC Al-Linux 667Mhz  g++ -O3 (2.96?)              14.66  
O2K R10000           KCC -O3 +K3 --no_exceptions  18.26
IMB SP2 332MHz       KCC kcc3.4d -O3 +K3          27.56