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How to traverse layout hierarchy?

VT202502243045

Problem statement: I have a hierarchical layout(called as  input_cell_view). I want to select all instances of Required_cell and place a copy the same instances along with parameters at the same x_coordinate:y_coordinate in another cell view(called as target_cellView).

Stratergy 1: Recursively opening up all instances and finding the coordinates.
Remarks: Very Slow and inefficient. Why is this not as fast as "leHiSearch" for getting the instances?

Strategy 2: Using "leSearchHierarchy"
Remarks: The returned list points to the master cell and I have no idea how to get the bBox or the parameters of the instance.

Strategy 3: Using "dbFlattenInst" or "dbFlattenInst2" (I understand that both are the same??)
Remarks: This actually throws up errors saying that i cannot flatten the cellview. The error seems very confusing.
The exact error is "*WARNING* (DB-220834): dbFlattenInstOrVia: Cannot flatten instance I6800 because it has no associated master. This could be because the master has been removed from disk, or is not correctly specified in the cds.lib file, or is unavailable on the network, for example. Check for such issues and retry."
I have checked all the aspects mentioned above and could not find any problems.


Strategy 4: Using "leHiSearch" and saving the output to .csv file.
Remarks: The .csv file does not contain the "ROTATION" of the instances. It does not contain the parameters passed to the instances.

Please suggest some methods for solving my problem statement. 
I hope my explanation of the problem is proper. Else, I can try to explain it better.

Regards,
V.S.

  • This is what I use for layout/schematic hierarchy lists
    I got this a post

    Open a cellview ( layout or schematic )
    load the procedures
    Execute the command in the CIW findInstHier(geGetEditCellView())
    It will output the instDb path list so you can get the inst variable values


    procedure(hierarchy_traversal(cellview listofNand instHier)
    let((newHier nextcellview)
    foreach(inst cellview~>instances
    listofNand = cons(append1(instHier inst) listofNand)
    )

    foreach(inst cellview~>instances
    if(inst~>isAnyInst then
    if(rexMatchp("symbol" inst~>viewName) then
    if(ddGetObj(inst~>libName inst~>cellName "schematic") then
    nextcellview = dbOpenCellViewByType(inst~>libName inst~>cellName "schematic" "schematic" "r")
    else nextcellview = nil)
    else if(ddGetObj(inst~>libName inst~>cellName inst~>viewName) then
    nextcellview = dbOpenCellViewByType(inst~>libName inst~>cellName inst~>viewName "maskLayout" "r")
    else nextcellview = nil)
    )
    when(nextcellview
    newHier = append1(instHier inst)
    listofNand = hierarchy_traversal(nextcellview listofNand newHier))
    )
    )
    listofNand
    )); end of hierarchy_traversal

    procedure(findInstHier(cv); instance hier path
    let( (cv1 instofNand listofNand instHier
    )
    foreach(inst cv~>instances
    instofNand = cons(list(cv inst) instofNand))

    listofNand = foreach(mapcar x instofNand list(cv x) x)

    foreach(inst cv~>instances
    when(inst~>isAnyInst
    if(rexMatchp("symbol" inst~>viewName) then
    if(ddGetObj(inst~>libName inst~>cellName "schematic") then
    cv1 = dbOpenCellViewByType(inst~>libName inst~>cellName "schematic" "schematic" "r")
    else cv1 = nil)
    else if(ddGetObj(inst~>libName inst~>cellName inst~>viewName) then
    cv1 = dbOpenCellViewByType(inst~>libName inst~>cellName inst~>viewName "maskLayout" "r")
    else cv1 = nil)
    )
    when(cv1
    instHier = append1(list(cv) inst)
    listofNand = hierarchy_traversal(cv1 listofNand instHier))
    ))
    listofNand
    ));end of findInstHier

    Paul

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