The present invention is a system and method for determining criticality
probability of each node, edge and path of the timing graph of a digital
circuit in the presence of delay variations. The delay of each gate or
wire is assumed to consist of a nominal portion, a correlated random
portion that is parameterized by each of the sources of variation and an
independent random portion. Correlations are taken into account. Both
early mode and late mode timing are included; both combinational and
sequential circuits are handled; static CMOS as well as dynamic logic
families are accommodated. The criticality determination complexity is
linear in the size of the graph and the number of sources of variation.
The invention includes a method for efficiently enumerating the critical
path(s) that is/are most likely to be critical.