Region-Based Partial Dead Code Elimination on Predicated Code

Abstract. This paper presents the design, implementation and experimental evaluation of a practical region-based partial dead code elimination (PDE) algorithm on predicated code in an existing compiler framework. Our algorithm processes PDE candidates using a worklist and reasons about their partial deadness using predicate partition graphs. It operates uniformly on hyperblocks and regions comprising basic blocks and hyperblocks. The result of applying our algorithm to an SEME region is optimal: partially dead code cannot be removed without changing the branching structure of the program or potentially introducing new predicate defining instructions. We present statistic evidence about the PDE opportunities in the 12 SPECint2000 benchmarks. In addition to exhibit small compilation overheads, our algorithm achieves moderate performance improvements in 8 out of the 12 benchmarks on an Itanium machine. Our performance results and statistics show the usefulness of our algorithm as a pass ...

• Type: Conference
• Year: 2004
• Where: CC
• Authors: Qiong Cai, Lin Gao 0002, Jingling Xue
• Keywords: Algorithm, Algorithm Processes Pde, CC 2004, Dead Code, Programming Languages