Using the XL Compilers for Blue Gene

Using the XL Compilers for Blue Gene

This document discusses specific considerations for developing, compiling, and optimizing C/C++ and Fortran applications for the Blue Gene/L PowerPC ® 440d processor architecture and its Double Hummer floating-point unit.

Optimization and Programming Guide - XL Fortran Advanced Edition V10.1 for Linux

This guide contains information on advanced programming topics, such as application porting, interlanguage calls with C or C++, library development, application optimization and parallelization, and the XL Fortran Advanced Edition for Linux high-performance libraries.

Language Reference - XL Fortran Advanced Edition V10.1 for Linux

The Language Reference contains information about the Fortran programming language as supported by IBM, including language extensions for portability and conformance to non-proprietary standards.

Compiler Reference - XL Fortran Advanced Edition V10.1 for Linux

This book contains reference information about the various compiler options, pragmas, macros, environment variables, and built-in functions provided by XL Fortran Advanced Edition V10.1 for Linux.

Exploiting the Dual Floating Point Units in Blue Gene/L

The IBM® Blue Gene®/L supercomputer consists of up to 65,536 compute nodes. Each compute node contains 2 Power PC® 440 processors, each enhanced with a specially designed dual Floating Point Unit (FPU). The presence of a second FPU on the Blue Gene/L processors theoretically allows double the performance on floating point algorithms over just using a single FPU. The IBM XL compilers can automatically take advantage of the dual FPU unit, but performance gains achieved by doing so depend strongly on the properties of the source code. The attached paper describes the implementation of the dual FPU in Blue Gene/L and how to effectively exploit its performance capabilities.

Code Optimization with the IBM XL Compilers

The IBM XL compiler family offers C, C++, and Fortran compilers built on an industry-wide reputation for robustness, versatility and standards compliance. A significant strength of these compilers is in their optimization capabilities, the ability to improve code generation and produce fast-executing code on PowerPC-based systems. This document introduces the most important capabilities and describes the compiler options, source constructs, and techniques that you can use to maximize the performance of your application.