Author: Russell Reagan
Date: 20:46:16 06/22/04
Go up one level in this thread
On June 22, 2004 at 22:55:17, Joshua Shriver wrote: >Anyone here tried doing tests to see what compilers produce the best binaries? > >I've heard gcc (while portable) can be kinda slow at times compared to Intel's >compiler. > >Are there any compilers out there that are fine tuned to Opteron? >Know with the G5 the xl compiler is better than gcc. > >What is the best compiler for the the various processors? >xl for G5? icc for Intel? compaqs suite for Alpha, what for Opteron? > >Sincerely, >Joshua Shriver I'll tell what my experience has been. Keep in mind that I haven't tested this in quite a few months, so things may have changed. The latest versions I have used are: MSVC .NET 2003 Intel 8 (Linux) GCC 3.3.1 (Cygwin, Linux) For any given program, any of them may produce the fastest code. I've had GCC produce code that was 20% faster than MSVC or Intel. In general though, GCC comes in third of this group. However, more recent updates have been improved quite a bit, and it is often very competitive with MSVC and Intel. I haven't used the most recent version of GCC (3.4). Maybe it is another improvement. Anyway, here is how it usually works out for me: MSVC is the fastest, if you are willing to (and have the knowledge to) tweak compiler options for a while (I've spent several hours doing this before: tweak, recompile, benchmark, repeat). This is how I produced the fastest Crafty binary for 32-bit AMD machines a while back. Intel is a close second usually. If you can get IPO and PGO to work together, then it is often faster than MSVC. Sometimes I have a heck of time getting them to work together. I don't know why. Maybe it's the user :) GCC is usually third. More recently, it has been a close third. Maybe 3.4 puts it ahead of the others, but I haven't used it yet. Compilers for the Opteron are probably very shaky at this point. I don't mean they are unstable. I mean since they are still being developed, this month one might be the fastest, next month another. Plus it all depends on your situation. Some people have access to beta versions of MSVC for the Opteron (I think these would be the fastest at present), while others only have GCC, and others only have an older version of MSVC for the Opteron, in which the emphasis isn't really on optimizations. They just wanted people to be able to compile their stuff for the Opteron early on, and get it ready, or so I've heard. One other thing to consider is that GCC has been able to compile for 64-bit machines long before the Opteron was ever around, so it may do very well on the Opteron.
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.