Why aren't there any xor\xnor cells in my netlist, although statistically there should be. Is this due to the poor netlist optimization capabilities of the openlane flow or are they excluded for some reasons? @User I would love to use an sky130_fd_sc_hd__xor2_1 in my add-on netlist, which I add to the design after synthesis. Are their any deep state problems with x(n)or-s ? Thanks for your answer in advance.

This is more of a question for the Openlane team, not me. There are, in my opinion, way too many cells in the "don't use" list, which is just a cop-out for a router that wasn't doing a good job.

Thanks Tim, it's just that the cell shows up in your open_pdks/sky130/openlane/sky130_fd_sc_hd/*no_synth.cells list, so that's why I was asking you for some insight.* I hope that the Openlane team will answer eventually. Cheers !

Right, but everything inside the

openlane/

directory in open_pdks is just dictated to me by the Openlane team, and I add it to the repository.