The test case is extracted from a large hierarchical design. RTL changes affect 4 flops and 3 output ports. GOF auto ECO uses 4 gates and 2.1 in area to fix the logic, while conformal ECO uses 28 gates and 29.2 in area to fix the logic. All gates in ECO use driver 'X4'.
|ECO Result||Total Cells||Non-Buffer||Invert||Buffer||Area|
GOF generates a patch having three inputs, two outputs and 5 gates in total.
Figure 1 GOF ECO patch
While Conformal ECO generates a big patch with tens inputs and outputs, total 28 gates.
Figure 2 Conformal ECO patch
The files can be downloaded to reproduce the result
gof -lib mp16.lib imp.v -ref ref.v -run eco.gpl