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Virtuoso Constraints SKILL code: correct my cstFindFirstConstraint syntax

dfink

I'm trying to get the ConstraintID of a particular constraint in the tech file foundry CG:

orderedSpacings(
( minOppExtension "METAL5" "VIA45" (0.020 0.11) 'ref "Mn.EN.1 Mn.EN.2" )

)

my skill code:

techdb = techGetTechFile( ddGetObj("tsmc13rf"))

FoundryID = cstFindConstraintGroupIn(techdb "foundry")

ConstID = cstFindFirstConstraint(FoundryID "minOppExtension" list("METAL5") list(0.02 0.11)

println(ConstID)

Running this code in the CIW gives:

*WARNING* (CST-300016): Constraint def 'minOppExtension' is not a layer constraint registry.

nil

t

The cstFindFirstConstraint is failing with ConstID having a nil value. 

Why is this warning happening?  Please help me understand how to properly format the t_constraintDefName in the cstFindFirstConstraint.

  • correction:  the ConstID variable set command does have the 2nd closing parenthesis in my code, just missed it when copying it to this post:

    ConstID = cstFindFirstConstraint(FoundryID ConstDef list("METAL5") list(0.02 0.11))

  • I found a solution. 

    I'm guessing that because minOppExtension is 2 layer check, the cstFindFirstConstraint expects tx_layer... to be a list of the 2 layers from the minOppExtension ordered spacing.  It fails if only 1 layer is provided to cstFindFirstConstraint.  

    cstFindFirstConstraint works after I provided the list of both layers:

    ConstID = cstFindFirstConstraint(FoundryID "minOppExtension" list("METAL5" "VIA45") )

    specifying the extension parameter numbers also works:

    ConstID = cstFindFirstConstraint(FoundryID "minOppExtension" list("METAL5" "VIA45") list(list(0.020 0.11)))

  • The content of this warning leaves much to be desired:

    *WARNING* (CST-300016): Constraint def 'minOppExtension' is not a layer constraint registry.

    It is not descriptive of the issue at all and even a bit misleading..

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