Optimizing C++/Introduction
This page may need to be One of the main reason for preferring C++ over simpler, higher-level programming languages is that C++ allows the construction of complex software in a way that makes more efficient use of hardware resources than when using these other languages. The language does not guarantee efficient code automatically, but provides a toolchest that aids programmers in the pursuit of efficiency. Sloppy C++ code may be no more efficient than higher-level implementations of the same algorithms, but a good C++ programmer with knowledge of the language can write software that is efficient from the first cut and then optimize the code further. This book provides techniques guidelines for writing efficient code and optimizing existing software.
Often, there is no single solution to a programming problem that is optimal for all cases. Thus, optimization generally does not mean writing optimally performing software; rather, it means incrementally changing (refactoring) software to increase it's performance, bringing it closer to optimality.
Such optimization requires, first, that the software source is written in a sufficiently modular way, to isolate the performance critical parts, and then to use tools, libraries, knowledge, and time, to change those parts in a way to increase the overall execution speed of the overall software.
Nowadays, many optimizations are already performed by compilers, and then they are no longer a programmer's burden. This book discusses higher-level optimizations that present compilers are not (yet) able to perform.
This book is aimed at readers already familiar with the C++ language, who want to use it to develop high performance application software or software libraries.
Almost all the optimization techniques presented are platform independent, and therefore there will be few references to specific operating systems, processor architectures, or compilers. Though, some of the presented techniques come out to be ineffective or not applicable in some combinations of operating system/processor/compiler.
