Abstract

This paper examines the role of dependence analysis in defimng bindingtime analyses (BTAs) for imperative programs and in establishing that such BTAs are safe. In particular, we are concerned with characterizing safety conditions under which a program specialize that uses the results of a BTA is guaranteed to terminate. Our safety conditions are formalized wa semantic characterizations of the statements in a program along two dimensions: srartc versus dynamic, and finite versus injinife. This permits us to give a semantic definition of “static-infinite computation”, a concept that has not been previously formalized. To illustrate the concepts, we present three different BTAs for an imperative language, we show that two of them me safe in the absence of “static-infinite computations”. In developing these notions, we make use of program represenrarion graphs, which are a program representation similar to the dependence graphs used in parallelizing and vectorizing compilers. In operational terms, our BTAs are related to the operation ofprogrrrm slicing, which can be implemented using such graphs. 1.

Citations