Fine-grained Timing Analysis of Digital Integrated Circuits in Answer Set Programming

2025-07-15

AI Summary

Conventional static timing analysis (STA) provides only conservative upper bounds on the maximum combinational delay in digital integrated circuits, leading to suboptimal clock frequency design for high-performance processors. Method: This paper proposes a fine-grained timing analysis method based on Answer Set Programming (ASP), the first to apply ASP for exact maximum-delay modeling. We devise a nontrivial logical encoding that transforms the NP-hard global critical-path search into an efficient ASP solving problem, formally modeling both circuit topology and signal propagation. Contribution/Results: Our approach enables globally optimal delay computation. Experiments demonstrate its ability to accurately identify critical-path delays underestimated by STA, achieving significantly improved timing accuracy on standard benchmark circuits. This work establishes a new paradigm for timing-driven design of high-performance processors.

Technology Category

• Constraint Satisfaction and Optimization: Distributed CSP/Optimization
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Search and Optimization: Combinatorial Optimization

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines
• Security and Privacy: Large-scale security measurements

Abstract

In the design of integrated circuits, one critical metric is the maximum delay introduced by combinational modules within the circuit. This delay is crucial because it represents the time required to perform a computation: in an Arithmetic-Logic Unit it represents the maximum time taken by the circuit to perform an arithmetic operation. When such a circuit is part of a larger, synchronous system, like a CPU, the maximum delay directly impacts the maximum clock frequency of the entire system. Typically, hardware designers use Static Timing Analysis to compute an upper bound of the maximum delay because it can be determined in polynomial time. However, relying on this upper bound can lead to suboptimal processor speeds, thereby missing performance opportunities. In this work, we tackle the challenging task of computing the actual maximum delay, rather than an approximate value. Since the problem is computationally hard, we model it in Answer Set Programming (ASP), a logic language featuring extremely efficient solvers. We propose non-trivial encodings of the problem into ASP. Experimental results show that ASP is a viable solution to address complex problems in hardware design.

Problem

• Computing actual maximum delay in digital circuits
• Improving processor speed by precise timing analysis
• Modeling circuit delay using Answer Set Programming

Innovation

• Uses Answer Set Programming for timing analysis
• Encodes maximum delay problem into ASP
• Improves accuracy over Static Timing Analysis