XL Fortran for AIX

Leading optimization and performance tuning technology

• XL Fortran for AIX supports automatic parallelization of sequential programs to make the most of the power of multi-core processors.
• It supports systems with processor architectures and operating systems that execute single instruction, multiple data (SMD) instruction sets. They include Vector Multimedia Extension (VMX) instructions and the POWER7 Vector Scalar Extension (VSX) instruction set.
• It supports OpenMP API Version 3.0 for parallel application development that simplifies data and task parallelism.
• You can generate profiling data for your application and then use the profiling data to optimize your application.

High-performance libraries

• Mathematical Acceleration Subsystem (MASS) consists of libraries of mathematical intrinsic functions tuned specifically for optimum performance on POWER architectures.
• Basic Linear Algebra Subprograms (BLAS) have high-performance, algebraic functions. They perform combined matrix multiplication and addition on general matrices or their transposes.
• The shared memory parallelization (SMP) runtime library supports both explicit and automatic parallel processing.
• The high-performance libraries help increase user productivity and improve runtime application performance. They speed initial development, resulting in fewer bugs and reduced long-term maintenance costs.

Profile-driven optimization

• Profile-directed feedback optimization collects information about a program run with typical input data. Then it applies transformations to the program based on that information. Profile-directed feedback can ensure the performance of the application is optimized for its important inputs.
• Application profile monitoring and profile directed feedback capabilities minimize the need for manual tuning to achieve desirable performance on large, complex applications.

Language standard compliance

• XL Fortran for AIX supports Fortran 2003, OpenMP 3.0, Fortran 95, Fortran 90 and FORTRAN 77.
• XL compilers help protect the investment in existing Fortran source and object code built with previous versions of the compilers. They allow users to rebuild and link all the components into the same applications using the latest compiler versions.
• Object code or libraries compiled with previous versions of XL Fortran are compatible with the newest XL Fortran compiler and runtime environment.
• By supporting industry-compliant programming languages, XL Fortran for AIX makes your applications portable.

Utilization tracking and reports

• XL Fortran for AIX produces reports that indicate the number of concurrent users using the compiler.
• Compiler reports are available in XML format. You can create tools to read and analyze the results.
• Reports for four optimization categories are provided. They include inlining, loop transformations, data reorganizations and profile-directed feedback information.
• Loop analysis reports provide information about loop nests on which the aggressive loop analysis was performed.
• Enhanced profiling reports provide additional information on the loop iteration count, the block and call count, and the number of cache misses for certain functions.