| # Metrics | |
| The [OpenROAD-flow-scripts](https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts) | |
| repository contains source files (e.g., LEF/DEF, Verilog, SDC, Liberty, | |
| RC extraction) and configuration files (e.g. `config.mk`) that enable the user to run | |
| a small set of example designs through our complete RTL-to-GDS flow. | |
| To keep track of the quality of the results, we maintain inside each | |
| design folder two files: | |
| 1. `metadata-base-ok.json` which contains all the relevant | |
| information extracted from the "golden" execution of the flow (i.e., | |
| last known good result). | |
| 2. `rules.json` which holds a set of rules that we use to | |
| evaluate new executions when a change is made. | |
| ## Checking against golden | |
| The evaluation checks for key metrics (e.g., worst slack, number of | |
| DRCs) to ensure that changes do not degrade too much with respect to the | |
| "golden" values. | |
| After you make a significant change, e.g., fixing a bug in a piece of | |
| code, or changing some configuration variable | |
| (`PLACE_DENSITY`), you should review the results and compare | |
| them with the "golden". To perform the check, you will need to run the | |
| following command: | |
| ``` shell | |
| cd OpenROAD-flow-scripts/flow | |
| # the clean_metadata is only required if you need to re-run | |
| make [clean_metadata] metadata | |
| ``` | |
| If the command above yields any error message, please review to | |
| make sure the change in metrics is expected and justifiable. If so, | |
| proceed to the next section to update the "golden" reference. | |
| ## Update process | |
| Update of the reference files is mandatory if any metrics became worse | |
| than the values limited by the `rules.json` (see previous | |
| section on how to perform the check). Also, it is a good idea to update | |
| the "golden" files if your changes have improved a metric, to ensure that | |
| the improvement will not be lost in the future. | |
| To update all the reference files: | |
| ``` shell | |
| cd OpenROAD-flow-scripts/flow | |
| make update_ok | |
| ``` | |
| In case you have a special reason to only update one of the files, you | |
| can do so with the following commands: | |
| ``` shell | |
| # update metadata-base-ok.json file for the design | |
| make update_metadata | |
| # update rules.json file for the design | |
| # this will use the current (+ a padding) metadata-base-ok.json | |
| # the padding ensures that small changes do not break the flow | |
| make update_rules | |
| ``` | |