Refactorings for Fortran and high-performance computing

Abstract

Not since the advent of the integrated development environment has a development tool had the impact on programmer productivity that refactoring tools have had for objectoriented developers. However, at the present time, such tools do not exist for high-performance languages such as C and Fortran; moreover, refactorings specific to highperformance and parallel computing have not yet been adequately examined. We observe that many common refactorings for object-oriented systems have clear analogs in procedural Fortran. The Fortran language itself and the introduction of object orientation in Fortran 2003 give rise to several additional refactorings. Moreover, we conjecture that many hand optimizations common in supercomputer programming can be automated by a refactoring engine but deferred until build time in order to preserve the maintainability of the original code base. Finally, we introduce Photran, an integrated development environment that will be used to implement these transformations, and discuss the impact of such a tool on legacy code reengineering.

Application of Modern Fortran to Spacecraft Trajectory Design and Optimization

“…Thus, many, if not most, legacy Fortran 77 codes can be used without modification in modern applications (e.g., the Copernicus use of SNOPT and SPICELIB). However, refactoring can often be advantageous, improving readability as well as laying the groundwork for other modernizations, as demonstrated in this paper and others [58,59]. A simple example of a refactored legacy subroutine is shown in Fig.…”

Safe Concurrency Introduction through Slicing

“…These approaches typically require pointer analyses to identify access to mutable data structures, a problem which is not evident in Erlang -which features single assignment -and other functional languages. Working within parallel languages such as x10, which embodies the partitioned global address space (PGAS) model, some work has been done in loop parallelisation [23], and, while these are not included in the main release, there have been some experiments in parallelisation in the Fortran refactoring tool Photran [25]. Other work on loop parallelisation [16] notes the importance of user input into the parallelisation process.…”

Revisiting loop transformations with x10 clocks

“…The need for Integrated Development Environment for parallel programming, and in particular for sophisticated refactoring transformations, has been argued by several groups in the past [6,8]. Although X10 provides an IDE based on Eclipse, it is not yet equipped with many refactoring transformations specific to X10.…”