Abstract

We present a linear-time algorithm for boundedtype programs that builds a directed graph whose transitive closure gives exactly the results of the standard (cubic-time) Control-Flow Analysis (CFA) algorithm. Our algorithm can be used to list all functions calls from all call sites in (optimal) quadratic time. More importantly, it can be used to give linear-time algorithms for CFAconsuming applications such as: ffl effects analysis: find the side-effecting expressions in a program. ffl k-limited CFA: for each call-site, list the functions if there are only a few of them ( k) and otherwise output "many". ffl called-once analysis: identify all functions called from only one call-site. 1 Introduction The control-flow graph of a program plays a central role in compilation -- it identifies the block and loop structure in a program, a prerequisite for many code optimizations. For first-order languages, this graph can be directly constructed from a program because information about flow of ...

Citations