1. A computer-implemented method comprising: obtaining a first test result vector corresponding to a first test pattern applied to a design under test, wherein the first test result vector indicates coverage of one or more events triggered by the first test pattern; obtaining a second test result vector corresponding to a second test pattern applied to a design under test, wherein the second test result vector indicates coverage of one or more events triggered by the second test pattern; and merging coverage data from at least the first test result vector and the second test result vector to obtain a merged event coverage vector, wherein the merged event coverage vector is smaller in size than a juxtaposition of the first test result vector and the second test result vector and wherein the merged event coverage vector indicates coverage of eents triggered by at least the first and second test patterns.