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	Optimization: Your worst enemy
		Optimization is what you do when the performance is insufficient.
		For inner-loop code, many hours of effort would usually result in a small improvement in performance, but it was generally understood by the programmers that unless you studied the generated machine code and did a number of calibrated experiments, any attempts at optimization would make the code worse.
		A naive approach, optimizing at the code-line level, is not nearly as effective as higher-order optimizations.
	www.flounder.com /optimization.htm (3484 words)

	Code Optimization
		The target code that is produced by a compiler is rarely ever as well optimized as it could be had it been created by a human.
		Code motion focuses on statements within a loop that force a computation of some sort, but where the result never changes no matter how many times the loop is executed.
		We would have liked to be able to generate C or C++ code after the compiler had run its optimizing routines, but this is simple and true evidence that even the most minute of code optimizations are beneficial.
	www.cs.engr.uky.edu /~jurek/cs541/Spring2002/optimization.html (2114 words)

	Code Optimization Using the GNU C Compiler LG #71
		One type of code optimization is strength reduction in which a "costly" operation is replaced by a less expensive one.
		From these optimization techniques and the various pieces of information that are required to apply them, the reader can appreciate the type of sophisticated and complex analysis that the compiler must carry out on the program.
		Code optimization is a field of active research and interested readers can refer to [1] for additional information.
	www.linuxgazette.com /issue71/joshi.html (2868 words)

	Optimizing Computer Runtime Using Data Prefetching and Code Optimization
		Code optimization and data prefetching are techniques for runtime optimization.
		Code optimization and data prefetching are two of a multitude of techniques that can enhance the performance of software.
		Code optimization and data prefetching are two techniques that will enable those platforms to do image processing at speeds that are acceptable.
	www.cis.rit.edu /class/simg707/Web_Pages/alain.htm (2857 words)

	Port80 Software: Articles: Fundamentals of Web Site Acceleration (Site not responding. Last check: 2007-10-29)
		Optimizing content and content delivery has been proven to improve Web page delivery speed in case studies conducted by the World Wide Web Consortium and has been espoused by Web optimization experts such as Andy King.
		Code optimization, cache control, and HTTP compression are strategies that focus on sending as little data as necessary as infrequently as possible to optimize performance in an existing Web application's front-end code and on the origin Web server delivering that content to Web browsers.
		Source code optimization should be implemented as a pre-deployment step through which all additions and changes to the front-end source code (including markup, style sheets, and client-side scripts) normally pass before being uploaded to the "live" production site or application.
	www.port80software.com /support/articles/webperformance (4040 words)

	Code Optimization (Site not responding. Last check: 2007-10-29)
		The term optimization is a bit of a misnomer because the code is not actually optimized to be the best it can be, but rather better than it was.
		A strategy to optimization is to identify the ``hot-spots'' in the code and spend the time working on those areas.
		However, someone with goofy optimization ideas might attempt to aid the compiler in optimizing the code down to as small as possible by writing really small code to begin with.
	www.csd.uwo.ca /~wozniak/cs447a-fall2001/notes/16_-_Code_Optimization (1923 words)

	Code Optimization
		Our purpose is to determine how well our code performs on a simple algorithm when not optimized at all, when optimized only by hand, when optimized only by the machine's optimizer, and when optimized by both hand and machine.
		For the code that was not hand optimized, the optimizer still made two comparisons, but it removed the mov statements from the loop and thereby modified the loop itself.
		The optimizer didn't improve the algorithm much, but it was able to provide a significant boost to speed by modifying the for loop and increasing the efficiency of the assembly code (hoisting unnecessary assginments out of the loop, etc.).
	www.student.carleton.edu /~HoelA (334 words)

	Programming Optimization: Techniques, examples and discussion
		Optimization is but one of many desirable goals in software engineering, and is often antagonistic to other important goals such as stability, maintainability, and portability.
		When all algorithmic optimization approaches have been tried and you are still an order of magnitude away from your target performance you may find that you have no choice but to analyze the situation at the lowest possible level.
		While the older architecture's assembly code had less of an improvement on the newer architecture, it was still faster, and using such old code would not be a liability as you suggest.
	www.azillionmonkeys.com /qed/optimize.html (7523 words)

	aiPop: Code Optimization and Compaction
		The aiPop optimizer suite was developed to reduce the code size, improve the code quality, and, optionally, speed up the execution of assembly or object files produced by a C compiler.
		The size of compiled C code is becoming increasingly critical in embedded systems, where the economic incentives to reduce ROM sizes are very compelling.
		Optimization of hand-written code is supported to some extent provided that it is similar to compiler-generated code.
	www.absint.com /aipop (505 words)

	Optimizing C and C++ Code
		This code generated is faster than if-else-if cascade code that is generated in cases where the case labels are far apart.
		This optimization can be performed easily without a major impact to the code by replacing pass by value parameters by const references.
		When coding is C, the declaration order of related code and functions can be arranged so that closely coupled code and data are declared together.
	www.eventhelix.com /RealtimeMantra/Basics/OptimizingCAndCPPCode.htm (1724 words)

	CommsDesign - Achieving Better Code Optimization in DSP Designs (Site not responding. Last check: 2007-10-29)
		What typically happens in software development is that the vast majority of the code, which is necessary for control but is lightly used in operation, is written and remains in C. The remaining small percentage of the code performs the computationally intensive signal processing portions of the algorithm.
		For the program developer, it pays to rewrite and optimize these blocks of code in C intrinsics or linear/hand assembly languages, since a small gain in efficiency can have a great deal of leverage in improving the overall performance of the machine.
		An important factor that affects code optimization and throughput in both the C and assembly languages is instruction latency.
	www.commsdesign.com /design_corner/showArticle.jhtml;jsessionid=JH2ELRCOWJHMGQSNDBCCKHQ?articleID=22100650 (2749 words)

	Port80 Software: Articles: Web Code Optimization (Site not responding. Last check: 2007-10-29)
		This is because the code is designed for speedy delivery to your browser's rendering engine, not for the human eye's perusal through the View Source option in your browser.
		An optimization tool must be truly aware of the intricacies of complex Web site code to safely remove white space without breaking code or causing display errors.
		Since the optimizations recommended here are purely for deployment, it makes much more sense to maintain a copy of the source files without any optimizations nicely formatted for editing and to generate an optimized version for deployment that is geared towards delivery.
	www.port80software.com /support/articles/webcodeoptimization (1632 words)

	Acovea Overview
		Optimization is far from being an exact science, given the diversity of hardware and software configurations.
		An optimization algorithm may be as simple as removing a loop invariant, or as complex as examining an entire program to eliminate global common sub-expressions.
		Many optimizations change what the programmer wrote into a more efficient form, producing the same result while altering underlying details for efficiency; other "optimizations" produce code that uses specific characteristics of the underlying hardware, such as special instruction sets.
	www.coyotegulch.com /products/acovea (2420 words)

	Code Optimization (Site not responding. Last check: 2007-10-29)
		The code is typically divided into a sequence of ``basic blocks.'' A basic block is a segment of straight-line code, with no branches in or out except a branch in at the top of the block, and a branch out at the bottom.
		In this example, there are three basic blocks: initialization code, the termination condition (which is located at the beginning of the loop), and the loop body and index increment code.
		In this code, we have two repeated examples of doing this: all those calculations of the address of i, all those times we load it and store it, and all those times we calculate the index.
	www.cs.nmsu.edu /~pfeiffer/classes/573/notes/optimize1.html (646 words)

	Christopher Ogren
		This optimization switches the position of two loops in a perfect loop nest (loops that have no intervening code between their headers, and no intervening code between their tails) usually moving one of the outer loops in the innermost position.
		The affects of this optimization include better register reuse; better stride performance (stride is the increment used to step through array storage to select the vector or matrix elements from the array) and less cache misses resulting in a faster execution time.
		The way this table is works is that the loop is assumed to operate over I from 1 to n with the operation in the expression column appearing inside the loop.
	www.cs.engr.uky.edu /~jurek/cs541/Spring2002/files/ChrisOgrenLauraReynolds4.html (1615 words)

	DSP Optimization Techniques (Site not responding. Last check: 2007-10-29)
		Some of these coding techniques in the URL reference can be applied later on when it is clear which routines need the most optimization.
		At higher optimization levels bugs in the code are sometimes introduced, so it is important to check the behavior of a compiler-optimized program against the reference implementation.
		Manually-written assembly code is usually the most efficient, but it is labor-intensive and it is not portable to other architectures.
	cnx.rice.edu /content/m12380/latest (1055 words)

	Code optimization - compiler
		Thanks to Timothy Prince for the note on architectures with Instruction Level Parallelism) Optimization techniques used by compilers may inspire good and efficient programming practices and are interesting in their own right.
		Before trying to perform 'hand optimization' please note the following points: 1) Remember that the compiler perform such optimizations anyway, so the benefit of doing them manually may be small or negative!.
		Programs used as performance tests, and perform no 'real' computations, should be written to avoid being 'completely optimized out', writing the 'results' to screen/file may be enough to fool the compiler.
	www.ibiblio.org /pub/languages/fortran/ch1-10.html (495 words)

	Code Optimization with IBM Compilers (Site not responding. Last check: 2007-10-29)
		IBM's compilers for Fortran, C, and C++ have many options that govern source code translation, machine code generation, and optimization, most of which are available on all IBM compilers.
		This level of optimization should be used only when you're sure that your code's correctness and performance will not be adversely affected by the individual options implied.
		Custom or generic libraries may not be optimized or optimizable to the same extent as the rest of your program.
	www.nersc.gov /~deboni/ibm.compilers.html (2299 words)

	Unrolling AltiVec, Part 3: Down and dirty loop optimization
		As always, the most important part of effective optimization is determining where the system is spending most of its time, and focusing your efforts there.
		One of the reasons not to be too quick to optimize code is that optimized code is often harder to read than unoptimized code.
		Because its code runs in the system idle loop, it ends up running the most (and thus getting the largest speedup) when the system is fairly quiet.
	www-128.ibm.com /developerworks/power/library/pa-unrollav3 (2924 words)

	The alto Project Home Page: Link-time Code Optimization
		Traditional optimizing compilers are limited in the scope of their optimizations by the fact that only a single function, or possibly a single module, is available for analysis and optimization.
		project is to develop whole-program dataflow analyses and code optimization techniques for link time program optimization; the current system is targeted to the DEC Alpha architecture, and produces code that is typically considerably faster than that produced using DEC's Om link-time optimizer (with or without profile-guided inter-file optimization carried out by the compiler).
		Code Specialization based on Value Profiles, by Robert Muth, Scott Watterson, and Saumya Debray.
	www.cs.arizona.edu /alto (431 words)

	Real World Technologies - Coding Challenge I
		Back in July 2002, we issued a coding challenge based upon the source code used in the Compilers and Performance article.
		To see if there might be some coding techniques that will produce good cross-platform code, or if the 'best' coding practices are to target a particular platform.
		The entrants submitted source code, so I compiled the C solutions myself with VC7, using the same flags, to make sure they were all on an even footing and test theory #1 above.
	www.realworldtech.com /page.cfm?AID=RWT041603000942 (492 words)

	Visual Studio Magazine - Speed Up Your VB.NET Code (Site not responding. Last check: 2007-10-29)
		You learn quickly that most of the optimization tricks you've learned for VB6 won't work under VB.NET.
		Note that I took all timings by compiling the code without debug support and after ticking the Enable Optimizations option in the Configuration Properties
		Optimizations page of the Project Properties dialog box.
	www.fawcette.com /vsm/2002_08/magazine/features/balena (194 words)

	Amazon.ca: Books: Code Optimization Techniques for Embedded Processors (Site not responding. Last check: 2007-10-29)
		Many existing compilers for DSPs and multimedia processors therefore produce code of insufficient quality with respect to performance and/or code size, and a large part of software for embedded systems is still being developed in assembly languages.
		Code Optimization Techniques for Embedded Processors discusses the state-of-the-art in the area of compilers for embedded processors.
		Code Optimization Techniques for Embedded Processors is intended for researchers and engineers active in software development for embedded systems, and for compiler developers in academia and industry.
	www.amazon.ca /exec/obidos/ASIN/0792379896 (555 words)

	P5 Optimization
		They have written code that is so bad as to be basically unusable for the purposes of any remotely practical Mandelbrot generation.
		Problem is, most programmers that can read the code and actually understand the issues well enough to understand how the code works are more likely to know a thing or too about optimization, and therefore know that the code shown is basically junk.
		While not a Pentium specific optimization, I believe it is important to understand how to use the floating point unit, to use the Pentium most effectively, far more so than previous generation x86s.
	www.azillionmonkeys.com /qed/p5opt.html (1286 words)

	Code Optimization
		It is a high level guide to learn which aspects can be considered in optimizing code but probably you need other literature to learn all details of the mentioned optimizations.
		This is most often the best way to optimize a program, but it is a fairly high level optimization and might be difficult to apply to existing programs.
		The code of the function body is moved right at the place of the function call, thus avoiding the call while providing the same functionality.
	library.simugraph.com /articles/opti/optimizing.html (4641 words)

	Developing Your Site for Performance Client Side Code Optimization
		It is best to comment source code extensively, to format it for maximum readability, and to avoid overly terse, but convoluted syntax that makes maintenance difficult.
		Later, one translates that source code using a compiler into some other form that is optimized for performance and protected from reverse engineering.
		This tool is the only one on the market today that provides a reference implementation for nearly all the optimizing features described here and that serves as a legitimate example of the "real world" value of code optimization.
	www.webpronews.com /webdevelopment/basicdevelopment/wpn-37-20041117DevelopingYourSiteforPerformanceClientSideCodeOptimization.html (865 words)

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