Inter-block code motion without copies
Philip H. Sweany · 1992
OF DISSERTATION INTER-BLOCK CODE MOTION WITHOUT COPIES Code motion is an important optimization for any compiler, and the necessity to include instruction scheduling in compilers for instruction-level-parallel (ILP) architectures makes code motion even more important in compilers for such architectures. Currently popular global scheduling techniques such as trace scheduling allow interblock code motion during scheduling, but require compensation copies which may make them less useful for many popular ILP architectures. This work measures the amount of inter-block code motion possible when compensation copies are not allowed and develops a global scheduling technique, dominator-path scheduling, which relies on such inter-block motion without copies. Tests show that dominator-path scheduling outperforms trace scheduling for a test suite of C programs compiled for the IBM RISC System/6000, a popular superscalar computer. Philip H. Sweany Department of Computer Science Colorado State Unive...