get_cdc_violations - 2020.2 English

Vivado Design Suite Tcl Command Reference Guide (UG835)

Document ID
UG835
Release Date
2020-11-18
Version
2020.2 English

Get a list of CDC violations from a previous report_cdc run

Syntax

get_cdc_violations [‑name <arg>] [‑regexp] [‑filter <arg>] [‑nocase]
    [‑quiet] [‑verbose] [<patterns>]

Returns

list of CDC violation objects

Usage

Name Description
[-name] Get the results with this name
[-regexp] Patterns are full regular expressions
[-filter] Filter list with expression
[-nocase] Perform case-insensitive matching (valid only when -regexp specified)
[-quiet] Ignore command errors
[-verbose] Suspend message limits during command execution
[<patterns>] Match CDC violations against patterns Default: * Values: The default search pattern is the wildcard *, or .* when -regexp is specified.

Categories

Object

Description

Gets a list of violation objects found in the design when the report_cdc command is run. The properties of individual violation objects can be queried using report_property or list_property commands for details of the violation.

Violation objects are associated with the clock-domain crossing paths in the current design. The design objects associated with a methodology violation object can be obtained using the -of_objects option of the appropriate get_* command, such as get_cells, or get_nets for instance.

Note: To improve memory and performance, the get_* commands return a container list of a single type of objects (e.g. cells, nets, pins, or ports). You can add new objects to the list (using lappend for instance), but you can only add the same type of object that is currently in the list. Adding a different type of object, or string, to the list is not permitted and will result in a Tcl error.

Arguments

-name <arg> - (Optional) Get the violations associated with the named CDC result set. In this case the report_cdc command must also have been run with the -name option.

-regexp - (Optional) Specifies that the search <patterns> are written as regular expressions. Both search <patterns> and -filter expressions must be written as regular expressions when this argument is used. Xilinx regular expression Tcl commands are always anchored to the start of the search string. You can add ".*" to the beginning or end of a search string to widen the search to include a substring. See http://perldoc.perl.org/perlre.html for help with regular expression syntax.
Note: The Tcl built-in command regexp is not anchored, and works as a standard Tcl command. For more information refer to http://www.tcl.tk/man/tcl8.5/TclCmd/regexp.htm.

-filter <args> - (Optional) Filter the results list with the specified expression. The -filter argument filters the list of objects returned by get_cdc_violations based on property values on the violations. You can find the properties on an object with the report_property or list_property commands.

The filter search pattern should be quoted to avoid having to escape special characters that may be found in net, pin, or cell names, or other properties. String matching is case-sensitive and is always anchored to the start and to the end of the search string. The wildcard “*” character can be used at the beginning or at the end of a search string to widen the search to include a substring of the property value.
Note: The filter returns an object if a specified property exists on the object, and the specified pattern matches the property value on the object. In the case of the "*" wildcard character, this will match a property with a defined value of "".
For string comparison, the specific operators that can be used in filter expressions are "equal" (==), "not-equal" (!=), "match" (=~), and "not-match" (!~). Numeric comparison operators <, >, <=, and >= can also be used. Multiple filter expressions can be joined by AND and OR (&& and ||). The following gets input pins that do NOT contain the “RESET” substring within their name:
get_pins * -filter {DIRECTION == IN && NAME !~ "*RESET*"}
Boolean (bool) type properties can be directly evaluated in filter expressions as true or not true:
-filter {IS_PRIMITIVE && !IS_LOC_FIXED}

-nocase - (Optional) Perform case-insensitive matching when a pattern has been specified. This argument applies to the use of -regexp only.

-quiet - (Optional) Execute the command quietly, returning no messages from the command. The command also returns TCL_OK regardless of any errors encountered during execution.
Note: Any errors encountered on the command-line, while launching the command, will be returned. Only errors occurring inside the command will be trapped.
-verbose - (Optional) Temporarily override any message limits and return all messages from this command.
Note: Message limits can be defined with the set_msg_config command.
<patterns> - (Optional) Match violations against the specified patterns. The default pattern is the wildcard '*' which gets all violations. More than one pattern can be specified to find multiple violations based on different search criteria.
Note: You must enclose multiple search patterns in braces, {}, or quotes, "", to present the list as a single element.

Examples

The following example reports the CDC violations found in the current design, then returns a list of all those violations:
report_cdc  
get_cdc_violations
The following example generates list of violations in the named CDC report, and then gets the pins associated with any violations found:
report_cdc -name cdc_1  
get_pins -of_objects [get_cdc_violations -name cdc_1]