Message-ID: <39F0EBB3.375FEFCE@email.com> From: Derek Chew X-Mailer: Mozilla 4.75 [en] (Windows NT 5.0; U) X-Accept-Language: en,ja,zh,zh-CN,zh-TW MIME-Version: 1.0 Newsgroups: comp.os.msdos.djgpp Subject: Runtime Speed Optimization Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.134.63.44 X-Original-Trace: 21 Oct 2000 12:04:04 +1100, 203.134.63.44 Lines: 36 Date: Sat, 21 Oct 2000 09:04:51 +0800 NNTP-Posting-Host: 203.134.64.67 X-Trace: news0.optus.net.au 972090245 203.134.64.67 (Sat, 21 Oct 2000 12:04:05 EST) NNTP-Posting-Date: Sat, 21 Oct 2000 12:04:05 EST Organization: CWO Customer - reports relating to abuse should be sent to abuse AT optus DOT net DOT au To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com over the past few weeks, I have been trying to develop a GUI for a DC Servo Motor system for my undergraduate project using DJGCC and Allgero... thanks to the excellent help of people like Laurence Withers, George Foot and the very helpful people in the Allegro mailing list, the project is nearing completion with some minor bugs still waiting to be stamped out.. but I currently have hit a major problem... The target system which I am running the GUI on is a 486DX4-100 with 8 Meg of RAM... the system is kind of slow and the control algorithm (linear/non-linear/Feed-Forward) are quite mathematically complex and the program makes a lot of outportb called to output the control signals to the external control circuitry... the development of the control algorithm took place concurrently using a text-based software and the control algorithm was done in a modular fashion in order to allow for easy interfacing with the Allegro based GUI later... Currently some of the problems faced are: 1) System's response time is way way too slow. Tried to speed things up by updating the display only every 1000 or even 10000 cycles but it is not helping 2) I'm not very sure how to provide options to optimize the compiling of the software for my target platform. Going to try -O3 but dunno what else can I do. Basically what I want to do is to optimize the program to run as fast as possible. Compiling time and program size is not an issue. 3) Sometimes the compiling of the source is done on an old 486SX Laptop which if I am not mistaken does not have an FPU. Does this mean the code generated will always use an FPU emulator even if I run the code later on a 486DX4-100? and is there a way to force the compiler to generate code which will always use an FPU? thanks a lot guys!