Partial dead code elimination on predicated code regions

  • Xue J
  • Cai Q
  • Gao L
  • 4


    Mendeley users who have this article in their library.
  • 1


    Citations of this article.


This paper presents the design, implementation and experimental evaluation of a practical region-based partial dead code elimination (PDE) algorithm on predicated code in the Open Research Compiler framework. Existing PDE algorithms are not applicable on predicated code due to the existence of if-converted branches in the program. The proposed algorithm processes all PDE candidates in a worklist and considers their partial deadness using predicate partition graphs. Our algorithm operates uniformly on individual hyperblocks as well as regions comprising of basic blocks and hyperblocks. The result of applying our algorithm to a single-entry multiple-exit (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 statistical evidence about the PDE opportunities in the 17 SPEC95 and SPEC00 integer benchmarks. Our algorithm achieves performance improvements in 12 out of the 17 benchmarks on an Itanium machine at small compilation overheads. Our results indicate that our algorithm can be used as a practical pass before instruction scheduling. Copyright © 2006 John Wiley & Sons, Ltd.

Author-supplied keywords

  • Code optimization
  • Hyperblocks
  • Partial dead code elimination
  • Performance evaluation
  • Predicate partition graphs
  • Predicated code
  • Predication
  • Regions

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Jingling Xue

  • Qiong Cai

  • Lin Gao

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free