Abstract

The quality of many optimizations and analyses of parallelizing compilers depends significantly on the ability to evaluate symbolic expressions and on the amount of information available about program variables at arbitrary program points. In this paper, we describe an effective and unified symbolic evaluation framework that statically determines the values of variables and symbolic expressions, assumptions about and constraints between variable values and the condition under which control flow reaches a program statement. We introduce program context, a novel representation for comprehensive and compact control and data flow analysis information. Program contexts are described as first order logic formulas which enable us to use public domain software for standard symbolic manipulation. Computations are represented as algebraic expressions defined over a program's problem size. Our symbolic evaluation techniques comprise accurate modeling of assignment and input/output statements, bra...

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