Unsupported expression for cell sg13g2_sdfbbp_1

[dnltz]

I found the following warning in OpenROAD and it looks like the stdcell lib has a type included: https://github.com/IHP-GmbH/IHP-Open-PDK/blob/dceb7e6bd1a877182c3ba32c2e238be08368fa3f/ihp-sg13g2/libs.ref/sg13g2_stdcell/lib/sg13g2_stdcell_typ_1p50V_25C.lib#L27289

Warning: Found unsupported expression 'SCE*SCD+SCE'*D' in pin attribute of cell 'sg13g2_sdfbbp_1' - skipping.

I can send a fix but can someone confirm this is a typo?

[dnltz]

@KrzysztofHerman

[KrzysztofHerman]

@dnltz thank you for reproducing this as well because we are aware of this warning. The person in charge has it in his pipeline but it you can provide the fix such as typo go ahead and do so so we can check it out using other tools as well.

[dnltz]

See https://github.com/IHP-GmbH/IHP-Open-PDK/pull/83

[sergeiandreyev]

Hi @dnltz , this is not a typo - this is an inversion, if you remove this symbol the function will not be correct. An option will be to change this symbol to !: (SCE*SCD)+(!SCE*D) Could you please try to change the function:

ff (IQ,IQN) {
      clear : "!RESET_B";
      clear_preset_var1 : "H";
      clear_preset_var2 : "L";
      clocked_on : "CLK";
      next_state : "(SCE*SCD)+(!SCE*D)";
      preset : "!SET_B";
      }

and give us your feedback whether it passes now.

[dnltz]

@sergeiandreyev still the same warning. I wonder if this expression is allowed at all and should be replaced by boolean operations since it defines the next state of a flip-flop.