Haoxing Ren

This paper introduces the first self-evolving logic synthesis framework, which leverages Large Language Model (LLM) agents to autonomously improve the source code of ABC, the widely adopted logic synthesis system. Our framework operates on the entire integrated ABC codebase, and the output repository preserves its single-binary execution model and command interface. In the initial evolution cycle, we bootstrap the system using existing prior open-source synthesis components, covering flow tuning, logic minimization, and technology mapping, but without manually injecting new heuristics. On top of this foundation, a team of LLM-based agents iteratively rewrites and evolves specific sub-components of ABC following our "programming guidance" prompts under a unified correctness and QoR-driven evaluation loop. Each evolution cycle proposes code modifications, compiles the integrated binary, validates correctness, and evaluates quality-of-results (QoR) on multi-suite benchmarks including ISCAS 85/89/99, VTR, EPFL, and IWLS 2005. Through continuous feedback, the system discovers optimizations beyond human-designed heuristics, effectively learning new synthesis strategies that enhance QoR. We detail the architecture of this self-improving system, its integration with ABC, and results demonstrating that the framework can autonomously and progressively improve EDA tool at full million-line scale.

Technology mapping involves mapping logical circuits to a library of standard cells. Traditionally, a full technology library is used, leading to a large search space and potential runtime overhead. Motivated by randomly sampled technology mapping case studies, we propose MapTune to address this challenge by utilizing reinforcement learning to make design-specific cell selection choices. By learning from the environment and guided by the reward, MapTune refines the cell selection process, resulting in a reduced search space and potentially improved mapping quality. The effectiveness of MapTune is evaluated on a wide range of benchmarks, different technology libraries, and various technology mappers. The empirical results demonstrate that MapTune achieves higher mapping accuracy and reduces delay/area across various circuit designs, technology libraries, and mappers. The article also discusses the Pareto-Optimal exploration and confirms the perpetual delay-area tradeoff. Conducted on benchmark suites ISCAS 85/89, ITC/ISCAS 99, VTR8.0, and EPFL benchmarks, the post-technology mapping and post-sizing quality-of-results (QoR) have been significantly improved, with average Area-Delay Product (ADP) improvement of 16.56% among all different exploration settings in MapTune. The improvements consistently remained for four different technologies (7 nm, 45 nm, 130 nm, and 180 nm) with various mappers including both state-of-the-art open-source and commercial synthesis tools.