Intel® 64 and IA-32 Architectures Optimization Reference Manual

APPENDIX AAPPLICATION PERFORMANCETOOLSIntel offers an array of application performance tools that are optimized to takeadvantage of the Intel architecture (IA)-based processors. This appendix introducesthese tools and explains their capabilities for developing the most efficient programswithout having to write assembly code.The following performance tools are available:• Intel ® C++ Compiler and Intel ® Fortran Compiler — Intel compilersgenerate highly optimized executable code for Intel 64 and IA-32 processors. Thecompilers support advanced optimizations that include vectorization for MMXtechnology, the Streaming SIMD Extensions (SSE), Streaming SIMD Extensions 2(SSE2), Streaming SIMD Extensions 3 (SSE3), and Supplemental StreamingSIMD Extensions 3 (SSSE3).• VTune Performance Analyzer — The VTune analyzer collects, analyzes, anddisplays Intel architecture-specific software performance data from the systemwideview down to a specific line of code.• Intel Performance Libraries — The Intel Performance Library family consistsof a set of software libraries optimized for Intel architecture processors. Thelibrary family includes the following:— Intel ® Math Kernel Library (Intel ® MKL)— Intel ® Integrated Performance Primitives (Intel ® IPP)• Intel Threading Tools — Intel Threading Tools consist of the following:— Intel Thread Checker— Thread ProfilerA.1 COMPILERSIntel compilers support several general optimization settings, including /O1, /O2,/O3, and /fast. Each of them enables a number of specific optimization options. Inmost cases, /O2 is recommended over /O1 because the /O2 option enables functionexpansion, which helps programs that have many calls to small functions. The /O1may sometimes be preferred when code size is a concern. The /O2 option is on bydefault.The /Od (-O0 on Linux) option disables all optimizations. The /O3 option enablesmore aggressive optimizations, most of which are effective only in conjunction withprocessor-specific optimizations described below.A-1