Incremental meta-data construction for VLSI design databases

Abstract

VLSI design databases are typically based on object-oriented data models, which provide primitives for modeling and manipulating design objects and their inter-relationships. However, in practice it is rather difficult for end users (i.e. circuit designers) to understand these primitives, let alone interact with them directly. Unfortunately, existing systems assume that it is the user's responsibility to explicitly build up the meta-data, by which is meant attribute and relationship information. This paper presents a novel incremental meta-data construction paradigm, which is based on (1) a structured design history model, and (2) the specifications of tool-specific execution semantics. Using this paradigm, the authors design and implement algorithms that automatically establish per-object attributes and inter-object relationships as a side effect of CAD tool execution. Consequently the rich modeling capability of an object-oriented database can be fully exploited in a design environment without circuit designers' participation in meta-data construction.<>