Intel® 64 and IA-32 Architectures Optimization Reference Manual

CHAPTER 3GENERAL OPTIMIZATION GUIDELINESThis chapter discusses general optimization techniques that can improve the performanceof applications running on processors based on Intel Core microarchitecture,Intel NetBurst microarchitecture, Intel Core Duo, Intel Core Solo, and Pentium Mprocessors. These techniques take advantage of microarchitectural described inChapter 2, “Intel® 64 and IA-32 Processor Architectures.” Optimization guidelinesfocusing on Intel dual-core processors, Hyper-Threading Technology and 64-bit modeapplications are discussed in Chapter 8, “Multi-Core and Hyper-Threading Technology,”and Chapter 9, “64-bit Mode Coding Guidelines.”Practices that optimize performance focus on three areas:• tools and techniques for code generation• analysis of the performance characteristics of the workload and its interactionwith microarchitectural sub-systems• tuning code to the target microarchitecture (or families of microarchitecture) toimprove performanceSome hints on using tools are summarized first to simplify the first two tasks. the restof the chapter will focus on recommendations of code generation or code tuning tothe target microarchitectures.This chapter explains optimization techniques for the Intel C++ Compiler, the IntelFortran Compiler, and other compilers.3.1 PERFORMANCE TOOLSIntel offers several tools to help optimize application performance, includingcompilers, performance analyzer and multithreading tools.3.1.1 Intel ® C++ and Fortran CompilersIntel compilers support multiple operating systems (Windows*, Linux*, Mac OS* andembedded). The Intel compilers optimize performance and give application developersaccess to advanced features:• Flexibility to target 32-bit or 64-bit Intel processors for optimization• Compatibility with many integrated development environments or third-partycompilers.• Automatic optimization features to take advantage of the target processor’sarchitecture.3-1