公开(公告)号：CA2288614A1

公开(公告)日：2001-05-08

申请号：CA2288614

申请日：1999-11-08

Applicant: IBM CANADA

Inventor： BLAINEY ROBERT JAMES ,  ARCHAMBAULT ROCH GEORGES

IPC: G06F9/45

Abstract: Loop allocation for optimizing compilers includes the generation of a progra m dependence graph for a source code segment. Control dependence graph representations of the nested loops, from innermost to outermost, are generated and data dependence graph representations are generated for each level of nested loop as constrained by the control dependence graph. An interference graph is generated with the nodes of the data dependence graph. Weights are generated for the edges of the interference graph reflecting the affinity between statements represented by the nodes joined by the edges. Nodes in the interference graph are given weights reflecting resource usage by the statements associated with the nodes. The interference graph is partitioned using a profitability test based on the weights of edges and nodes and on a correctness test based on the reachability of nodes in the data dependence graph. Code is emitted based on the partitioned interference graph.