A method and apparatus are presented that can analyze the performance of
an integrated circuit design at multiple corners, under multiple modes,
and for multiple objectives efficiently and simultaneously. The
extraction, timing analysis, and optimization functions are integrated
into a mechanism that provides a novel problem formulation. A plurality
of virtual timing graphs are maintained and updated simultaneously by
providing a data structure that can efficiently store operating data for
an arbitrary number of conditions at each node. This data structure is
populated according to the design, and as optimizations are made, the
operating data for all design conditions is updated simultaneously.
Timing violations can be reported across all corners and modes. By
integrating this multi-corner multi-mode analysis with circuit
optimization, a convergent mechanism is provided. In this way, design
constraints are evaluated simultaneously for an arbitrary number of
design conditions.