Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: g++ 3.4 and -fprofile-generate

Author: Eugene Nalimov

Date: 12:51:03 02/16/05

Go up one level in this thread


On February 16, 2005 at 15:26:50, Robert Hyatt wrote:

>On February 16, 2005 at 15:15:53, Frank Phillips wrote:
>
>>On February 16, 2005 at 13:19:46, Robert Hyatt wrote:
>>
>>>On February 16, 2005 at 13:09:14, Frank Phillips wrote:
>>>
>>>>Has anybody got any experience with g++ 3.4 for amd64 (x86_64) - for Linux?
>>>>
>>>>I have been using the profile generated optimisation option, but the code it
>>>>produces is no faster then with simple -O3.
>>>>
>>>>I simply compile with -fprofile-generate
>>>>then run,
>>>>then recompile with -fprofile-use.
>>>>
>>>>The relevant *.gcno, *.gcda files are produced.  Must be doing something
>>>>wrong.....
>>>>
>>>>Frank
>>>
>>>
>>>It has never worked well for me.  In fact, it usually crashes when I try to do
>>>this for crafty.  ICC (Intel's compiler) works fine and that is what I use
>>>myself.
>>>
>>
>>Oh... the last version of ICC I used produced fast 32 bit code.  Does it now do
>>amd 64 bit ?
>>
>>Frank
>>
>
>No.  Sorry.  I completely overlooked the AMD-64 in your text as that has become
>so common to see over the past year.  ICC is 32 bits only although it will be 64
>bit before long...

ICC 8.1 supports x86, x64, and IPF.

Thanks,
Eugene

>
>>
>>>You need a good test set of data so that it can accurately predict each branch
>>>and move code to optimize branch prediction at run-time...  The positions you
>>>test need to pretty accurately represent what happens in a real game.



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.