Symbolic Program Analysis and Optimization for Parallelizing Compilers

A program flow analysis framework is proposed for parallelizing compilers. Within this framework, symbolic analysis is used as an abstract interpretation technique to solve many of the flow analysis problems in a unified way. Some of these problems are constant propagation, global forward substitution, detection of loop invariant computations, and induction variable substitution. The solution space of the above problems is much larger than that handled by existing compiler technology. It covers many of the cases in benchmark codes that other parallelizing compilers can not handle. Employing finite difference methods, the symbolic analyzer derives a functional representation of programs, which is used in dependence analysis. A systematic method for generalized strength reduction based on this representation is also presented. This results in an effective scheme for exploitation of parallelism and optimization of the code. Symbolic analysis also serves as a basis for other code generation optimizations such as elimination of redundant computations and restructuring of arithmetic expressions.

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