âAutoPhase: Compiler Phase-Ordering for High Level Synthesis With Deep Reinforcement Learningâ, 2019-01-15 (; backlinks; similar)â :
The performance of the code generated by a compiler depends on the order in which the optimization passes are applied. In high-level synthesis, the quality of the generated circuit relates directly to the code generated by the front-end compiler.
Choosing a good orderâoften referred to as the phase-ordering problemâis an NP-hard problem.
In this paper, we evaluate a new technique to address the phase-ordering problem: deep reinforcement learning. We implement a framework in the context of the LLVM compiler to optimize the ordering for HLS programs and compare the performance of deep reinforcement learning to state-of-the-art algorithms that address the phase-ordering problem.
Overall, our framework runs one to two orders of magnitude faster than these algorithms, and achieves a 16% improvement in circuit performance over the
-O3compiler flag.