get_timing_paths - 2025.2 English - UG835

Description

Gets timing path objects that meets the specified criteria. It predefines timing paths to pass to the report_timing command for instance and creates custom reporting and analysis.

The get_timing_paths command is very similar to the report_timing command. However, get_timing_paths returns timing path objects to query for properties, or passes to other Tcl commands for processing, where report_timing returns a file or a string.

Arguments

-from <args> - (Optional) Defines the starting points of the timing paths to run the analysis. You can specify ports, pins, or cells can be specified as timing path startpoints. For a clock object, it analyzes all startpoints clocked by the named clock.

-rise_from <args> - (Optional) Similar to the -from option, but considers only the rising edge of signals coming from the startpoints. For a clock object, it analyzes only the paths launched by the rising edge of the clock as startpoints.

-fall_from <args> - (Optional) Similar to the -from option, but considers only the falling edge of signals coming from the startpoints. For a clock object, it analyzes only the paths launched by the falling edge of the clock are considered as startpoints.

-to <args> - (Optional) Specifies the endpoints or destination objects of timing paths to run the analysis.You can specify ports, pins, and cell objects as endpoints. For a clock object, it analyzes endpoints clocked by the named clock.

-rise_to <args> - (Optional) Similar to the -to option, but considers only the rising edge of signals going to the endpoints. For a clock object, it analyzes only the paths captured by the rising edge of the named clock as endpoints.

-fall_to <args> - (Optional) Similar to the -to option, but considers only the falling edge of signals going to the endpoints for timing analysis. For a clock object, it analyzes only the paths captured by the falling edge of the named clock as endpoints.

-through <args> - (Optional) Considers paths through the specified pins, cell instance, or nets only for timing analysis. You can specify individual -through (or -rise_through and -fall_through ) points in sequence to define a specific path through the design for analysis. The order of the specified through points is important to define a specific path. You can also specify through points with multiple objects, in which case the timing path passes through any of the specified through objects.

-rise_through <args> - (Optional) Similar to the -through option, but it performs timing analysis on paths with a rising transition at the specified objects.

-fall_through <args> - (Optional) Similar to the -through option, but it performs timing analysis on paths with a falling transition at the specified objects.

-delay_type <arg> - (Optional) Specifies the type of delay to analyze when running the timing report. The valid values are min, max, min_max, max_rise, max_fall, min_rise, min_fall. The default setting for -delay_type is max.

-setup - (Optional) Check for setup violations. This is the same as specifying -delay_type max.

-hold - (Optional) Check for hold violations. This is the same as specifying -delay_type min.

-max_paths <arg> - (Optional) The maximum number of paths to output when sorted by slack; or the maximum number of paths per path group when sorted by group, as specified by -sort_by. The value must be greater than or equal to 1. The default value is 1 and returns the single worst timing path or the worst path per group.

-nworst <arg> - (Optional) The number of timing paths to show to each endpoint. The timing report shows the N worst paths based on the specified value. The value must be greater than or equal to 1. The default setting is 1.

-unique_pins - (Optional) Shows only one timing path per each unique pin or group of pins. This is a boolean option, enabled by the use.

-inter_slr <args> - (Optional) Reports the timing paths based on their SLR-crossing characteristics. Ensure to specify one of the following values: any_crossing, data_crossing, clock_crossing, or no_crossing.

-routable_nets - (Optional) Reports the number of routable nets traversed as a property of the returned timing paths.

-slack_greater_than <arg> - (Optional) Report timing on paths with a calculated slack value greater than the specified value. Provides a range of slack values of specific interest with -slack_lesser_than.

-slack_lesser_than <arg> - (Optional) Report timing on paths with a calculated slack value less than the specified value. Provides a range of slack values of specific interest with -slack_greater_than.

-group <args> - (Optional) Reports timing for paths in the specified path groups.

-no_report_unconstrained - (Optional) Does not report timing on unconstrained paths.

-user_ignored - (Optional) Shows the timing paths that are ignored during timing analysis because the user has specified set_false_path or set_clock_groups timing constraints. This is a boolean option, enabled by its use.

-sort_by [ slack | group ] - (Optional) Sort timing paths by path groups, or by slack values. The default sort order is by slack values.

-filter <args> - (Optional) Filters the results list with the specified expression. The -filter argument filters the list of objects returned by get_timing_paths based on property values on the timing paths. You can find the properties on an object with the report_property or list_property commands. For timing path object, some properties "DATAPATH_DELAY", "ENDPOINT_PIN" and "ENDPOINT_CLOCK" filters results.

The following example gets the first 100 most critical timing paths objects and returns only those from the path group clk_tx_clk_core_1:

get_timing_paths -max_paths 100 -filter {GROUP == clk_tx_clk_core_1}

get_pins * -filter {DIRECTION == IN && NAME !~ "*RESET*"}

-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.

-cell <arg> - (Optional) Applies the get_timing_paths command to the specified cell. You can specify the cells by name, or as an object returned by the get_cells command.

Examples

The following example gets the five worst timing paths from the specified endpoint and reports all the properties of the fourth timing path in the list:

report_property -all [lindex [get_timing_paths -to [get_ports led_pins[*]]\
-nworst 5] 3]

The following example defines a procedure called custom_report and report the 100 worst paths from the clk_tx_clk_core_1 path group:

proc custom_report { listOfPaths } {
   puts [format {%-40s %-40s %-20s %-20s %7s} "Startpoint" "Endpoint" \
      "Launch Clock" "Capture Clock" "Slack"]
   puts [string repeat "-" 140]
   foreach path $listOfPaths {
      set startpoint [get_property STARTPOINT_PIN $path]
      set startclock [get_property STARTPOINT_CLOCK $path]
      set endpoint [get_property ENDPOINT_PIN $path]
      set endclock [get_property ENDPOINT_CLOCK $path]
      set slack [get_property SLACK $path]
      puts [format {%-40s %-40s %-20s %-20s %7s} $startpoint $endpoint \
         $startclock $endclock $slack]
   }
}
set paths [get_timing_paths -group clk_tx_clk_core_1 -max_paths 100]\
custom_report $path

The following example uses get_timing_paths to perform a timing analysis on the specified paths:

set paths [get_timing_paths -group clk_tx_clk_core_1 -max_paths 100]
report_timing -of_objects $paths

The following example is the equivalent of:

report_timing -group clk_tx_clk_core_1 -max_paths 100

The following example returns timing paths where the logic levels are greater than the specified number of logic levels.

get_timing_paths -max_paths 1000 -filter {LOGIC_LEVELS > 1}

The following example returns the number of SLR crossings in the worst setup path with the datapath crossing SLRs:

get_property SLR_CROSSINGS [get_timing_path -inter_slr data_crossing]

See Also

• report_property
• report_timing