Optimal and Efficient Speculation-Based Partial Redundancy Elimination

Existing profile-guided partial redundancy elimination (PRE) methods use speculation to enable the removal of partial redundancies along more frequently executed paths at the expense of introducing additional expression evaluations along less frequently executed paths. While being capable of minimizing the number of expression evaluations in some cases, they are, in general, not computationally optimal in achieving this objective. In addition, the experimental results for their effectiveness are mostly missing. This work addresses the following three problems: (1) Is the computational optimality of speculative PRE solvable in polynomial time? (2) Is edge profiling -- less costly than path profiling -- sufficient to guarantee the computational optimality? (3) Is the optimal algorithm (if one exists) lightweight enough to be used efficiently in a dynamic compiler? In this paper, we provide positive answers to the first two problems and promising results to the third. We present an algor...

• Type: Conference
• Year: 2003
• Where: CGO
• Authors: Qiong Cai, Jingling Xue
• Keywords: Algorithm, CGO 2003, Computational Optimality, Expression Evaluations, Software Engineering