9 Transformations

KAP transformations convert standard Fortran constructs into forms that have better serial performance and which make more efficient use of the memory hierarchy of Compaq's Alpha computers.

In addition, KAP identifies opportunities for concurrent execution of loops, identifying them with directives for the Fortran compiler, and transforms vectorizable loops to enhance the vectorization capability of the Fortran compiler.

This chapter describes some of the possible transformations in this process:

• Memory management for data locality

• Loop reordering

• Serial optimizations

• Dusty-Deck IF transformations

• Loop unrolling

• Loop rerolling

Unless otherwise noted, the examples in this chapter were run with the command qualifiers /optimize=5 , /roundoff=2 , and /scalaropt=2 .

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