Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: MS compiler issue [OT]

Author: Gerd Isenberg

Date: 10:23:24 10/15/05

Go up one level in this thread


>  00021 83 fb 03         cmp ebx, 3                             ;main.c:22.2
>  00024 b8 00 00 00 00   mov eax, 0                             ;main.c:22.2
>  00029 0f 92 c0         setb al                                ;main.c:22.2
                          sub xxx, eax

hmm - also four instructions and one additional register.
I don't understand why compilers have so much trouble to do simple arithmetic
with booleans, specially compares with carry flag - using sbb or adc
instructions.

Does Intel also perform the div by reciprocal mul?
May you post the complete assembly of the routine?


>
>although generally I have found the VC++ 2003 Platform
>SDK compiler (which is a free download) produces executables
>as good overall as Intel.

Really?

>
>I tried the VC++ 2005 beta 1 compiler and got some very
>good performance numbers, but it was buggy at that stage.
>
>--Jon

Sometimes i am impressed about the optimization tricks of the compilers,
but sometimes simply shocked about their unability ;-)

Gerd



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.