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How do I avoid the renaming of long net names during netlisting/flattening?

skillet

I've been able to read a Verilog file into DFII via ihdl to create a netlist view. My intent is to create an autoLayout view, so I go to "Tools --> Floorplan/Netlist in my window that shows me the netlist view and then go to the Hierarchy Browser. After preparing all my settings I click on "Hierarchy ---> Generate Physical Hierarchy". Eventually I get my autoLayout view.

Everything seems hunky-dory, except that some nets have gotten renamed to something like "_LoNgNeTnAmE108(123)". It appears the flattener didn't like the original net name (even though it's not really that much longer and I don't think there are restrictions on net names in the CDBA, or maybe it's 256 bytes but I'm nowhere near that length).

The problem now is that I can't correlate some of my nets in the Verilog netlist with the nets in my floorplan.

I haven't found any documentation on net renaming or the generation of a mapping file that would help me sort this out. There's nothing to be found in the adpFlatten directory that I could take advantage of.

Any comments what else I could try to remedy this problem? I need my symbolic netlist match exactly my Verilog netlist. BTW, my netlist is flat. In other words, there is no hierarchy involved. It's just a bunch of blocks (represented by abstracts) interconnected by a bunch of nets. 

The DFII version I'm using is IC5.1 on Solaris (Sparc V9).

Parents

  • Hi Lawrence,

    So far I haven't had any luck. However, I need to clarify a few things. When I started this thread, I thought that long net names were changed by the flattener. The reason I thought so is because I checked the database and looked for a specific net name that I found in the autoLayout view, using

    dbFindNetByName(geGetEditRep() "_LoNgNeTnAmExyz")

    in the netlist view. Well, turns out I must have searched for the wrong net name and when nil was returned, I thought this proved that the netlister causes the net mapping. Now when I do a

    geGetEditRep()~>nets~>name

    I can see all kinds of nets with the prefix "_LoNgNeTnAmE". So that clarified for me that ihdl renames nets.

    So now to ihdl. I'm generally able to read in a netlist using our Linux version of DFII. The SPARC Solaris versions we have (incl. the latest one, namely 5.10.41_USR6.127.29) crash with a segmentation fault during VerilogIn. When trying to read the Verilog file via the Linux version

    layout.exe_64 version 5.1.0-64b 10/28/2008 16:04 (cicamd4) $
    sub-version 5.10.41_USR6-64b.127.29

    it doesn't seem to recognize the entry

    ihdl maxNetNameLength int 1024

    in my .cdsenv file in my directory. I first left CDS_LOAD_ENV untouched, but even after setting

    setenv CDS_LOAD_ENV CWD

    it doesn't work. I'm stuck. If you had any other suggestion, I'd be very greatful.

Reply

  • Hi Lawrence,

    So far I haven't had any luck. However, I need to clarify a few things. When I started this thread, I thought that long net names were changed by the flattener. The reason I thought so is because I checked the database and looked for a specific net name that I found in the autoLayout view, using

    dbFindNetByName(geGetEditRep() "_LoNgNeTnAmExyz")

    in the netlist view. Well, turns out I must have searched for the wrong net name and when nil was returned, I thought this proved that the netlister causes the net mapping. Now when I do a

    geGetEditRep()~>nets~>name

    I can see all kinds of nets with the prefix "_LoNgNeTnAmE". So that clarified for me that ihdl renames nets.

    So now to ihdl. I'm generally able to read in a netlist using our Linux version of DFII. The SPARC Solaris versions we have (incl. the latest one, namely 5.10.41_USR6.127.29) crash with a segmentation fault during VerilogIn. When trying to read the Verilog file via the Linux version

    layout.exe_64 version 5.1.0-64b 10/28/2008 16:04 (cicamd4) $
    sub-version 5.10.41_USR6-64b.127.29

    it doesn't seem to recognize the entry

    ihdl maxNetNameLength int 1024

    in my .cdsenv file in my directory. I first left CDS_LOAD_ENV untouched, but even after setting

    setenv CDS_LOAD_ENV CWD

    it doesn't work. I'm stuck. If you had any other suggestion, I'd be very greatful.

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