Scheduling expression trees for delayed-load architectures

Venugopal, R and Srikant, YN (2002) Scheduling expression trees for delayed-load architectures. In: Journal of Systems Architecture, 48 (4-5). 151-173 .

PDF Scheduling_expression.pdf - Published Version Restricted to Registered users only Download (489kB) | Request a copy

Abstract

In this paper we consider the problem of scheduling expression trees on delayed-load architectures. The problem tackled here takes root from the one considered in [Proceedings of the ACM SIGPLAN '91 Conf. on Programming Language Design and Implementation, 1991. p. 256] in which the leaves of the expression trees all refer to memory locations. A generalization of this involves the situation in which the trees may contain register variables, with the registers being used only at the leaves. Solutions to this generalization are given in [ACM Trans. Prog. Lang. Syst. 17 (1995) 740, Microproc. Microprog. 40 (1994) 577]. This paper considers the most general case in which the registers are reusable. This problem is tackled in [Comput. Lang, 21 (1995) 49] which gives an approximate solution to the problem under certain assumptions about the contiguity of the evaluation order: Here we propose an optimal solution (which may involve even a non-contiguous evaluation of the tree). The schedule generated by the algorithm given in this paper is optimal in the sense that it is an interlock-free schedule which uses the minimum number of registers required. An extension to the algorithm incorporates spilling. The problem as stated in this paper is an instruction scheduling problem. However, the problem could also be rephrased as an operations research problem with a difference in terminology. (C) 2002 Elsevier Science B.V. All rights reserved.

Item Type:	Journal Article
Publication:	Journal of Systems Architecture
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Keywords:	Compilers;Instruction scheduling;Expression trees;Incremental scheduling
Department/Centre:	Division of Electrical Sciences > Computer Science & Automation
Date Deposited:	28 Jul 2011 07:32
Last Modified:	28 Jul 2011 07:32
URI:	http://eprints.iisc.ac.in/id/eprint/39390

Actions (login required)

View Item