<!-- MHonArc v2.4.4 --> <!--X-Subject: [MUD-Dev] Re: Question on c++ switch optimization, and parsers in general. --> <!--X-From-R13: "Oqnz X. Fubeagba" <nqnzNcubravk.Bevaprgba.SRG> --> <!--X-Date: Mon, 8 Feb 1999 20:34:06 -0800 --> <!--X-Message-Id: 19990208233237.A22601#mesa,Princeton.EDU --> <!--X-Content-Type: text/plain --> <!--X-Reference: 199902090329.UAA00854@ami-cg.GraySage.Edmonton.AB.CA --> <!--X-Head-End--> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <html> <head> <title>MUD-Dev message, [MUD-Dev] Re: Question on c++ switch optimization, and parsers</title> <!-- meta name="robots" content="noindex,nofollow" --> <link rev="made" href="mailto:adam#phoenix,Princeton.EDU"> </head> <body background="/backgrounds/paperback.gif" bgcolor="#ffffff" text="#000000" link="#0000FF" alink="#FF0000" vlink="#006000"> <font size="+4" color="#804040"> <strong><em>MUD-Dev<br>mailing list archive</em></strong> </font> <br> [ <a href="../">Other Periods</a> | <a href="../../">Other mailing lists</a> | <a href="/search.php3">Search</a> ] <br clear=all><hr> <!--X-Body-Begin--> <!--X-User-Header--> <!--X-User-Header-End--> <!--X-TopPNI--> Date: [ <a href="msg00368.html">Previous</a> | <a href="msg00370.html">Next</a> ] Thread: [ <a href="msg00366.html">Previous</a> | <a href="msg00372.html">Next</a> ] Index: [ <A HREF="author.html#00369">Author</A> | <A HREF="#00369">Date</A> | <A HREF="thread.html#00369">Thread</A> ] <!--X-TopPNI-End--> <!--X-MsgBody--> <!--X-Subject-Header-Begin--> <H1>[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</H1> <HR> <!--X-Subject-Header-End--> <!--X-Head-of-Message--> <UL> <LI><em>To</em>: <A HREF="mailto:mud-dev#kanga,nu">mud-dev#kanga,nu</A></LI> <LI><em>Subject</em>: [MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</LI> <LI><em>From</em>: "Adam J. Thornton" <<A HREF="mailto:adam#phoenix,Princeton.EDU">adam#phoenix,Princeton.EDU</A>></LI> <LI><em>Date</em>: Mon, 8 Feb 1999 23:32:37 -0500</LI> <LI><em>Reply-To</em>: <A HREF="mailto:mud-dev#kanga,nu">mud-dev#kanga,nu</A></LI> </UL> <!--X-Head-of-Message-End--> <!--X-Head-Body-Sep-Begin--> <HR> <!--X-Head-Body-Sep-End--> <!--X-Body-of-Message--> <PRE> On Mon, Feb 08, 1999 at 08:29:46PM -0700, Chris Gray wrote: > - emit an inline table containing offsets to the code to be executed. > Table is directly indexed by a multiple of the switch value, > usually with a range-test to handle the default. A variant is > to have branch instructions in the table, and to branch to > the appropriate one which then branches to the final code. The computed GOTO lives! My approach would be: write it however it is easiest for you, the author, to understand. If it turns out to be unacceptably slow, and if profiling the execution shows that that *is* the bottleneck (both of which I consider unlikely), then think about changing it and worry about how your compiler is doing it. Adam -- adam#princeton,edu "There's a border to somewhere waiting, and a tank full of time." - J. Steinman </PRE> <!--X-Body-of-Message-End--> <!--X-MsgBody-End--> <!--X-Follow-Ups--> <HR> <ul compact><li><strong>Follow-Ups</strong>: <ul> <li><strong><A NAME="00372" HREF="msg00372.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></strong> <ul compact><li><em>From:</em> Ben Greear <greear#cyberhighway,net></li></ul> </UL></LI></UL> <!--X-Follow-Ups-End--> <!--X-References--> <UL><LI><STRONG>References</STRONG>: <UL> <LI><STRONG><A NAME="00366" HREF="msg00366.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></STRONG> <UL><LI><EM>From:</EM> Chris Gray <cg#ami-cg,GraySage.Edmonton.AB.CA></LI></UL></LI> </UL></LI></UL> <!--X-References-End--> <!--X-BotPNI--> <UL> <LI>Prev by Date: <STRONG><A HREF="msg00368.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></STRONG> </LI> <LI>Next by Date: <STRONG><A HREF="msg00370.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></STRONG> </LI> <LI>Prev by thread: <STRONG><A HREF="msg00366.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></STRONG> </LI> <LI>Next by thread: <STRONG><A HREF="msg00372.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></STRONG> </LI> <LI>Index(es): <UL> <LI><A HREF="index.html#00369"><STRONG>Date</STRONG></A></LI> <LI><A HREF="thread.html#00369"><STRONG>Thread</STRONG></A></LI> </UL> </LI> </UL> <!--X-BotPNI-End--> <!--X-User-Footer--> <!--X-User-Footer-End--> <ul><li>Thread context: <BLOCKQUOTE><UL> <LI><strong><A NAME="00371" HREF="msg00371.html">[MUD-Dev] code profiling</A></strong>, Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Tue 09 Feb 1999, 06:00 GMT <UL> <LI><strong><A NAME="00373" HREF="msg00373.html">[MUD-Dev] optimizing code</A></strong>, diablo <a href="mailto:diablo#best,com">diablo#best,com</a>, Tue 09 Feb 1999, 06:31 GMT <UL> <LI><strong><A NAME="00374" HREF="msg00374.html">[MUD-Dev] Re: optimizing code</A></strong>, Hans-Henrik Staerfeldt <a href="mailto:hhs#cbs,dtu.dk">hhs#cbs,dtu.dk</a>, Tue 09 Feb 1999, 14:58 GMT </LI> </UL> </LI> </UL> </LI> <LI><strong><A NAME="00366" HREF="msg00366.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></strong>, Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Tue 09 Feb 1999, 03:31 GMT <UL> <LI><strong><A NAME="00369" HREF="msg00369.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></strong>, Adam J. Thornton <a href="mailto:adam#phoenix,Princeton.EDU">adam#phoenix,Princeton.EDU</a>, Tue 09 Feb 1999, 04:34 GMT <UL> <LI><strong><A NAME="00372" HREF="msg00372.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></strong>, Ben Greear <a href="mailto:greear#cyberhighway,net">greear#cyberhighway,net</a>, Tue 09 Feb 1999, 06:01 GMT </LI> </UL> </LI> </UL> <UL> <li><Possible follow-up(s)><br> <LI><strong><A NAME="00368" HREF="msg00368.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></strong>, Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Tue 09 Feb 1999, 03:54 GMT <UL> <LI><strong><A NAME="00370" HREF="msg00370.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers in general.</A></strong>, T. Alexander Popiel <a href="mailto:popiel#snugharbor,com">popiel#snugharbor,com</a>, Tue 09 Feb 1999, 04:41 GMT </LI> </UL> </LI> </UL> </LI> <LI><strong><A NAME="00355" HREF="msg00355.html">[MUD-Dev] Re: Question on c++ switch optimization, and parsers i</A></strong>, Chris Gray <a href="mailto:cg#ami-cg,GraySage.Edmonton.AB.CA">cg#ami-cg,GraySage.Edmonton.AB.CA</a>, Mon 08 Feb 1999, 06:11 GMT </LI> </UL></BLOCKQUOTE> </ul> <hr> <center> [ <a href="../">Other Periods</a> | <a href="../../">Other mailing lists</a> | <a href="/search.php3">Search</a> ] </center> <hr> </body> </html>