--- name: "lvx" section: "1" platform: "linux" package: "alliance" version: "5.1.1-3" release: "Debian 10 (Buster)" platforms: ["linux"] url: "https://new.carta.tech/lvx" --- # lvx(1) Logical Versus eXtracted net-list comparator ## NAME lvx - Logical Versus eXtracted net-list comparator ## SYNOPSIS - **lvx** *format1 format2 filename1 filename2* **\[ -a \] \[ -u \] \[ -o \] \[ -f \]** ## DESCRIPTION **lvx** compares two gate-level or block level net-list. The goal is to compare a specification net-list (logical net-list), the input to a place and route tool, with the physical net-list (extracted net-list) obtained by the [**cougar**(1)](/cougar/1.md) extractor.\ The net-list 1 is considered as the logical net-list and net-list 2 as the extracted net-list.\ \ **lvx** is an one-level hierarchical tool: - The two net-list are flattened, if the **-f** option is present, to the cells contained in the catalog file. The path to the catalog file is indicated in the [**MBK\_CATA\_LIB**(1)](/MBK_CATA_LIB/1.md) variable for the cell library, and in the [**MBK\_WORK\_LIB**(1)](/MBK_WORK_LIB/1.md) variable with the name [**MBK\_CATAL\_NAME**(1)](/MBK_CATAL_NAME/1.md) for user blocks ( [**catal**(5)](/catal/5.md) ) that are not to be flattened. - For both net-list, the instances are considered as black-boxes. - The two net-list must have the same external connectors names. - The two net-list must have the same instances names. - The two net-list must have the same signals names for unconnected signals. - The two net-list cannot directly contain transistors. Comparison is performed in three steps: - Compare terminals. - Compare instances. - Compare connections. - Compare unconnected signals. If an error occurs during first or second step, a message is immediately displayed and the third step will not start: **lvx** cannot compare connections (signals) if terminals or instances are not equivalent.\ The **-o** option allows to order connectors if the steps described before have been reached successfully. *Extracted\_netlist* is then saved on disk. The file get the name *filename2* suffixed by the value of [**MBK\_OUT\_LO**(1)](/MBK_OUT_LO/1.md) variable.\ Routers add automatically empty feed-through cells. These cells must not be taken into account in the comparison. A cell that have the *F* attribute in the catalog file ( **catal (5)** ) is considered as feed-through cell, and are deleted, in memory, from the net-list where it appears. ## OPTIONS - **-a** Some routers generate layout with several physical connectors for power and ground ( *VDD* or *VSS* ). If those connectors are not internally connected, they will have different indexed names ( *VDD1* , *VDD2* etc...) in the extracted net-list. It is possible to perform reduction on those power and ground connectors before comparison, using the -a option. After reduction, each instance contains only one *VDD* connector and one *VSS* connector, as the main figure. - **-o** In this case, **lvx** produces a modified net-list (saved with the name *filename2* ), which is a copy of net-list 2 with ordered connectors. Terminals and instance connectors are relisted in the order of the models in net-list 1. The saved net-list is done with the [**MBK\_OUT\_LO**(1)](/MBK_OUT_LO/1.md) format, so user has to set this variable before running **lvx** . If he does not, default value is used, and net-list 1 could be lost if filename are identical and input format same as output format.\ If -a option is used, then the saved net-list is the reduced net-list with only one *VDD* and one *VSS* . - **-u** This option force **lvx** to check the consistency of unassigned signals between the two netlists. - **-f** The two net-lists are flattened to the leaf cells contained in the catalog file. Usually the extracted net-list is a flatten net-list, while the logical one can be a hierarchical net-list. ## EXAMPLES With *logical\_netlist* named amd2901.vst and the corresponding *extracted\_netlist* as amd2901.al containing multiple power connectors, the command line is :\ - **lvx** vst al amd2901 amd2901 -a\ ## OUTPUT FILES - *filename2*.***xx*** Netlist view saved when the **-o** option is present. The suffixe depend on the [***MBK\_OUT\_LO***(1)](/MBK_OUT_LO/1.md) environment variable. ## ENVIRONMENT VARIABLES - ***MBK\_CATA\_LIB*** contains the directories where the cell librtaries are. ***MBK\_WORK\_LIB*** contains the directory path of the working directory, usually set to ***.*** (dot). - ***MBK\_OUT\_LO*** contains the expected format of the netlist output. - ***MBK\_CATAL\_NAME*** contains the name of the user cell catalog. ## SEE ALSO [**cougar**(1)](/cougar/1.md), [**MBK\_OUT\_LO**(1)](/MBK_OUT_LO/1.md), [**MBK\_WORK\_LIB**(1)](/MBK_WORK_LIB/1.md), [**MBK\_CATA\_LIB**(1)](/MBK_CATA_LIB/1.md), [**MBK\_CATAL\_NAME**(1)](/MBK_CATAL_NAME/1.md), [**catal**(5)](/catal/5.md) . ## DIAGNOSTICS The string "\_logic" is appended to the net-list 1 and the string "\_extract", is appended to the net-list 2. Two kinds of error message can occur: - A fatal error causes the program to exit. It happens when one of the net-lists is not correct, **lvx** cannot construct internal structure for compare. - A compare error occurs when the figures are not identical. It happens when basic objects (instances, connectors) do not exist in both net-list, or when connections (signals) do not connect same terminals or instances in the two net-lists. Exit code 0 is returned for identical net-lists.