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List forming was changed in IC 6.1.5.65?

Slayer

 Hi all!

Could u pls. help me with  one issue. The questionis, that succession of shapes in list is change in IC6.1.5.65. I try to clarify this moment.

In pcell I use some subCells, after that pull up need shepes and forming list formshapes

example:

[CODE]

        shapesToCopy = setof(i car(instances)->master->shapes i->up||i->conn);
        foreach(i if(oddp(ng) cdr(reverse(instances)) instances)
            foreach(s shapesToCopy
                dbCopyFig(s pcCV list(i->xy "R0"));
            );
        );

[/CODE]

after that according to property on shapes I sort it in lists

[CODE] 

         foreach(s setof(i pcCV->shapes i->conn)
            case(s->conn
                ("gTop"
                    gatesTop = cons(s gatesTop);
                )
                ("gBot"
                    gatesBot = cons(s gatesBot);
                )
                ("sub"
                    substrates = cons(s substrates);
                )
            );end case
        );end foreach

[/CODE]

And In cdb version (on this version all works fine)  I have succession of shapes which were builded from left to right, but in IC6.1.5.65 shape which was on first position now on second, wich was on 4 position now on 3 and etc.

What's wrong? What were changed, and how to use pcells which were created under cdb version?

  • What's wrong is your assumption that the database is ordered. It never was in CDB and is not in OA either.

    Whilst empirically you may have observed that the data appeared to be ordered (possibily in the order it was created?) that was never a reasonable assumption - it is not documented as such, and having your code dependent upon some observed behaviour was asking for trouble. The underlying database could have been changed at any time for optimization reasons, and then things would have get messed up. Even doing simple operations on the database (in CDB) can cause the order to change.

    If you want the lists in an order sorted from left to right, use the sort() function to do that, with a comparison function which compares the coordinates. That's the only safe way of doing this.

    Regards,

    Andrew.

  •  Yes, function sort() is work around for this case, but I have a lot of devices in library, and now I must change a lot of pcell code and make db compare of layout to be insured that will no impacts for designers.

    Simple when we create shapes they have id number which increased step to step and when we takes shapes for process, for example: ccv()->shapes, I think this list should have shapes already sorted by id number isn't it? 

  • No, that is also not a valid assumption. For a start, the database ids will not remain the same from one session to the next. There is no guarantee that they will come out in the same order.

    In CDB there was a command to "compact" the database (similar to a defragment). In OA something similar happens automatically, so you can find the database order changing even with just a save.

    As I said before, the database is unordered, and so you should never treat it as ordered.

    It's unfortunate that your code will need changing, but it's because your code was incorrect in the first place and based in an invalid assumption. Using sort() is not a workaround, it's how the code should have been written in the first place.

    Apologies if this is a little harsh, but you should never write code based on emperical assumptions and expect it to work through different versions, let alone when the underlying database has changed completely.

    Regards,

    Andrew.

  • OA backfills released memory when new shapes are created, this means that the shapes you create are not always found in the creation order. This was documented in the adoption guide. 

    If you go back to the code creating the shapes, you can use create ROD objects and have them named according to their position. Then you can sort by the ROD names.

    Ted

  • Thx. for the one more solution, but I have already fixed all through sort function.

     sortShapeList = sort(unsortShapeList lambda((a b) caar(a~>bBox) > caar(b~>bBox)));

     

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