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Skill Pcell "undefined function pow" at eval during LVS

AdrienL

Hello,

I've been working on a PCell in skill for several days and it is not a piece of cake! I was able to fix most of my problems alone, but this time I really don't understand...

For a little of context I have a PCell that generates a layout and a schematic (therefore I have 2 pcDefinePCell).

When I generate the PCell (by loading the .il script) everything works fine. I see my layout and my schematic as expected.

When I implement the symbol of my pcell in a schematic, no problem, the layout is also generated as expected. DRC work perfectly.

But when I run the LVS, it won't work and I have this error:

Pcell evaluation for architectures_tests/pcell_inv/schematic generated information. See layer/purpose "marker/error" shape with property "drcWhy" for description. You can get more details from file /tmp/_pcEvala79387.

ERROR (OSSHNL-408): Failed to generate the netlist because of a Pcell evaluation error on cellview 'my_lib/pcell_inv/schematic'. Set simStopNetlistOnPcellFailure to "ignore" to prevent this error.

In the tmp file I have 2 times : *Error* eval: undefined function - pow

The thing is I don't have any "pow" function in my scripts... So I really don't understand.

I hope someone can help me. Thank you in advance!

Parents

  • You could try doing:

    _stacktrace=50
    sstatus(errsetTrace t)

    Then look in the /tmp file it mentions. This should give an idea about where the pow is being called from? pow() is an ADE function and not part of core SKILL (expt or ** should be used instead), but the trick is to find where it's called from first.

    One possibility might be if you are (say) calling CDF callbacks within your PCell code - given the name "pcell_inv" I'm assuming it contains instances of transistors in the schematics, and those might have CDF callbacks that call pow. If these aren't under your control, you could put this in your library's libInit.il :

    unless(isCallable('pow)
      procedure(pow(base expt) expt(base expt))
    )

    Regards,

    Andrew

  • in reply to Andrew Beckett

    I have an other problem now, the LVS (or the simulation in ADE) wont take the Pcell schematic, but the schematic generated when the script is loaded (with the default value).

    Should I create an different post?

Reply Children
  • in reply to AdrienL

    Hmm, I thought you said that it fixed it?

    By the way, the only way to reload the libInit.il within the same virtuoso session is to explicitly load() the file (it's loaded automatically on a first access trigger and obviously it can only trigger than once).

    If you send me a friend request on the forums with your email address, I can take a quick look with you via a screen-sharing session (this is not an invitation to people across the world to do the same - I don't have the capacity!)

    Andrew

  • in reply to Andrew Beckett

    It fixed the eval error problem indeed. But it unlocked new problems Sweat smile

    Understood for the libinit.il

    Thank you, I sent you one.

  • in reply to AdrienL

    Just to post the solution Andrew found:

    It was a simply that I used string format in my CDF parameters definition, but float in my PCell parameters definition.
    It seems that layout pcells automatically convert string to float (ex: 300n -> 0.3), but no the schematic pcells...
    As the schematic did not understand the given string parameter (expecting a float), it discarded it and used the default value. (However, it strange that I didn't have any warning or error message :o)

    So we changed the parameters definition from float to string, and used the function cdfParseFloatString() to convert string to usable float.

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