# Command Manual
OpenTimer shell interprets each command in three forms, *builder*, *action*, and *accessor*.
+ a builder command creates *lazy* tasks to build up a timing analysis framework
+ an action command triggers the timing update from the earliest task to the one that produces the result of the action call
+ an accessor command dumps static information without altering the internal data structure of the timer
| Command | Form | Description |
| :------ | :--- | :---------- |
| [read_celllib](#read_celllib) | builder | reads a liberty format library file |
| [read_verilog](#read_verilog) | builder | reads a gate-level verilog netlist |
| [read_spef](#read_spef) | builder | reads a file of net parasitics in SPEF |
| [read_sdc](#read_sdc) | builder | reads a Synopsys Design Constraint (sdc) file of version 2.1 |
| [read_timing](#read_timing) | builder | reads a TAU15 Contest assertion file of timing constraints |
| [set_units](#set_units) | builder | specifies the units used to compute timing values and report results |
| [set_at](#set_at) | builder | specifies the arrival time of an input port |
| [set_rat](#set_rat) | builder | specifies the required arrival time of an output port |
| [set_slew](#set_slew) | builder | specifies the transition time of an input port |
| [set_load](#set_load) | builder | specifies the load capacitance of an output port |
| [insert_gate](#insert_gate) | builder | inserts a gate (instance) to the design |
| [remove_gate](#remove_gate) | builder | removes a gate (instance) from the design |
| [repower_gate](#repower_gate) | builder | repowers a gate (instance) with a new cell |
| [insert_net](#insert_net) | builder | inserts an empty net to the design |
| [remove_net](#remove_net) | builder | removes a net from the design |
| [connect_pin](#connect_pin) | builder | connects a pin to a net |
| [disconnect_pin](#disconnect_pin) | builder | disconnects a pin from a net |
| [enable_cppr](#enable_cppr) | builder | enables common path pessimism removal analysis |
| [disable_cppr](#disable_cppr) | builder | disables common path pessimism removal analysis |
| [update_timing](#update_timing) | action | updates the timer to keep all timing values up-to-date |
| [report_timing](#report_timing) | action | reports the critical paths in the design |
| [report_at](#report_at) | action | reports the arrival time at a pin |
| [report_slew](#report_slew) | action | reports the transition time at a pin |
| [report_rat](#report_rat) | action | reports the required arrival time at a pin |
| [report_slack](#report_slack) | action | reports the slack at a pin |
| [report_tns](#report_tns) | action | reports the total negative slack of the design |
| [report_wns](#report_wns) | action | reports the worst negative slack of the design |
| [report_fep](#report_fep) | action | reports the total failing endpoints in the design |
| [report_area](#report_area) | action | reports the aggregate cell areas of the design |
| [report_leakage_power](#report_leakage_power) | action | reports the aggregate cell leakage power of the design |
| [license](#license) | accessor | shows the license information |
| [version](#version) | accessor | shows the version of the OpenTimer |
| [dump_timer](#dump_timer) | accessor | dumps the design statistics |
| [dump_taskflow](#dump_taskflow)| accessor | dumps the current lineage graph to a DOT format file |
| [dump_graph](#dump_graph) | accessor | dumps the current timing graph to a DOT format file |
The above list of commands is committed to be stable.
Other commands found in [shell.hpp](../../ot/shell/shell.hpp) but not listed in the table
may change in the future release.
---
## read_celllib
The `read_celllib` command reads a Liberty format library file.
In most cases, this is the first command to initialize a timing analysis framework.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -min | optional | use library for min delay calculation |
| -max | optional | use library for max delay calculation |
| filename | required | the name of the liberty file to read |
By default, OpenTimer use the `filename` for both min and max delay calculations, if none are given.
---
## read_verilog
The `read_verilog` command reads a gate-level verilog netlist and initializes the circuit graph
from the given libraries.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| filename | required | the name of the gate-level verilog netlist file to read |
The admissible format of verilog files to OpenTimer is described [here](../io/verilog.md).
---
## read_spef
The `read_spef` command reads a SPEF parasitics file.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| filename | required | the name of the SPEF file to read |
The admissible format of SPEF files to OpenTimer is described [here](../io/spef.md).
---
## read_sdc
The `read_sdc` command reads a Synopsys Design Constraint (SDC) file (version 2.1).
| Argument | Type | Description |
| :------- | :--- | :---------- |
| filename | required | the name of the SPEF file to read |
The supporting status of SDC commands is described [here](../io/sdc.md).
---
## read_timing
The `read_timing` command reads a [TAU15 Contest Timing Assertion](TAU15) file
to assert timing constraints.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| filename | required | the name of the timing assertion file to read |
---
## set_units
The `set_units` command specifies the units used to compute timing values and
report results.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -time unit | optional | the time unit (s) |
| -capacitance unit | optional | the capacitance unit (F) |
| -resistance unit | optional | the resistance unit (Ohm) |
| -voltage unit | optional | the voltage unit (V) |
| -current unit | optional | the current unit (A) |
| -power unit | optional | the power unit (W) |
The `unit` consists of a *numeric*, a *scale*, and a *type*.
Each unit is parsed through the following C++ regular expression.
```cpp
std::regex unit_regex("([\\+-]?\\d*\\.?\\d+)\\s*([fpnumkM]?)\\s*(s)", std::regex::icase);
```
For example, you can use the following:
+ set_unit -time 1ps -capacitance -1fF
+ set_unit -time 2ns -capacitance -2pF
By default, OpenTimer applies the unit from the file it parsed first (often library unit definitions)
and converts the later ones to this basis.
---
## set_at
The `set_at` command specifies the arrival time of an input port at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of the input port pin |
| delay | optional | the arrival time value |
| -min | optional | the minimum arrival time |
| -max | optional | the maximum arrival time |
| -rise | optional | the arrival time at the rising edge |
| -fall | optional | the arrival time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
If *delay* is not given, OpenTimer unsets the arrival time at the pin.
---
## set_rat
The `set_rat` command specifies the required arrival time of an output port at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of the input port pin |
| delay | optional | the required arrival time value |
| -min | optional | the minmum required arrival time |
| -max | optional | the maximum required arrival time |
| -rise | optional | the arrival time at the rising edge |
| -fall | optional | the arrival time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
If *delay* is not given, OpenTimer unsets the required arrival time at the pin.
---
## set_slew
The `set_slew` command specifies the transition time of an input port at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of the input port pin |
| slew | optional | the input transition time value |
| -min | optional | the minimum transition time |
| -max | optional | the maximum transition time |
| -rise | optional | the transition time at the rising edge |
| -fall | optional | the transition time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
If *slew* is not given, OpenTimer unsets the transition time at the pin.
---
## set_load
The `set_load` command specifies the load capacitance of an output port at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of the input port pin |
| load | optional | the load capacitance value |
| -min | optional | the minimum load capacitance |
| -max | optional | the maximum load capacitance |
| -rise | optional | the load capacitance at the rising edge |
| -fall | optional | the load capacitance at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
If *slew* is not given, OpenTimer unsets the transition time at the pin.
---
## insert_gate
The `insert_gate` command inserts a new gate (instance) upon a cell to the design.
The newly inserted gate is not connected to other gates or nets.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| gate_name cell_name | required | the names of the gate and name for the insertion operation |
---
## remove_gate
The `remove_gate` command removes a gate from the design.
All the connections associated with the gate are removed.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| gate_name | required | the name of the gate to remove from the design |
---
## repower_gate
The `repower_gate` command repowers a gate with another cell.
The new cell must have the same topology as the old cell.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| gate_name cell_name | required | the names of the gate and the cell for the repower operation |
---
## insert_net
The `insert_net` command inserts an empty net to the design.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| name | required | the names of the net to insert into the design |
---
## remove_net
The `remove_net` command removes a net from the design.
All components in the net will be disconnected.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| name | required | the names of the net to remove from the design |
---
## connect_pin
The `connect_pin` command connects a pin to a net.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| pin_name net_name | required | the names of the pin and the net to enable this connection |
---
## disconnect_pin
The `disconnect_pin` command disconnects a pin from the net it is connected to.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| pin_name | required | the names of the pin to enable this disconnection |
---
## enable_cppr
The `enable_cppr` command enables the common path pessimism removal analysis.
This triggers path-based timing update and can increase the runtime.
---
## disable_cppr
The `disable_cppr` command disables the common path pessimism removal analysis
and adopts only graph-based analysis.
---
## update_timing
The `update_timing` command updates the timer to keep all timing information
(slew, delay, slack) up-to-date.
This is the bottom-most call of every action command.
---
## report_timing
The `report_timing` command reports the timing critical paths in the design.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -num_paths k | optional | the number of paths to report |
| -min | optional | the min path |
| -max | optional | the max path |
| -rise | optional | the rising endpoint |
| -fall | optional | the falling endpoint |
If `-num_paths k` is not given, OpenTimer report the most critical path.
If neither `-min` nor `-max` is given, OpenTimer report the critical paths across both splits.
If neither `-rise` nor `-fall` is given, OpenTimer report the critical paths across both transitions.
---
## report_at
The `report_at` command reports the arrival time of a pin at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of a pin to query |
| -min | optional | the minimum arrival time |
| -max | optional | the maximum arrival time |
| -rise | optional | the arrival time at the rising edge |
| -fall | optional | the arrival time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
---
## report_slew
The `report_slew` command reports the transition time of a pin at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of a pin to query |
| -min | optional | the minimum transition time |
| -max | optional | the maximum transition time |
| -rise | optional | the transition time at the rising edge |
| -fall | optional | the transition time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
---
## report_rat
The `report_rat` command reports the required arrival time of a pin at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of a pin to query |
| -min | optional | the minimum required arrival time time |
| -max | optional | the maximum required arrival time time |
| -rise | optional | the required arrival time time at the rising edge |
| -fall | optional | the required arrival time time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
---
## report_slack
The `report_slack` command reports the slack of a pin at a given
min/max split and rise/fall transition.
| Argument | Type | Description |
| :------- | :--- | :---------- |
| -pin name | required | the name of a pin to query |
| -min | optional | the minimum slack time |
| -max | optional | the maximum slack time |
| -rise | optional | the slack time at the rising edge |
| -fall | optional | the slack time at the falling edge |
By default, OpenTimer assumes *min* split and *rise* transition.
---
## report_tns
The `report_tns` command reports the total negative slack
(the sum of negative slack across all endpoints)
in the design.
---
## report_wns
The `report_wns` command reports the worst negative slack in the design.
---
## report_fep
The `report_fep` command reports the total failing endpoints in the design.
---
## report_area
The `report_area` command reports the aggregate cell areas in the design.
---
## report_leakage_power
The `report_leakage_power` command reports the aggregate cell leakage power in the design.
---
## license
The `license` command shows the license information of OpenTimer.
Currently, OpenTimer is under MIT license and is completely free for use.
---
## version
The `version` command shows the version of OpenTimer in the form of *major*.*minor*.*patch*.
---
## dump_timer
The `dump_timer` command dumps the design statistics.
The output shows a summary of design size, number of pins, number of nets, units, and so on.
---
## dump_taskflow
The `dump_taskflow` command dumps the present lineage graph to a DOT format file.
You can use tools like [GraphViz][GraphViz] to visualize the graph.
---
## dump_graph
The `dump_graph` command dumps the present timing graph into a DOT format file.
You can use tools like [GraphViz][GraphViz] to visualize the graph.
* * *
[Cpp-Taskflow]: https://github.com/cpp-taskflow/cpp-taskflow/
[TAU15]: https://sites.google.com/site/taucontest2015/
[GraphViz]: https://dreampuf.github.io/GraphvizOnline/