Evaluating Inlining Techniques

For eciency and ease of implementation, many compilers implicitly impose an ``inlining policy'' to restrict the conditions under which a procedure may be inlined. An inlining technique consists of an inlining policy and a strategy for choosing a sequence of inlining operations that is consistent with the policy. The e€ectiveness of an inlining technique is a€ected by the restrictiveness of the inlining policy as well as the e€ectiveness of the (heuristic) inlining strategy. The focus of this paper is on the comparison of inlining policies and techniques, and the notions of power and ̄exibility are introduced. As a major case study, we identify and compare policies based on the version of the inlined procedure that is used. # 1998 Elsevier Science Ltd. All rights reserved.