Verilator Verification Features Tests

Copyright (c) 2022 Antmicro

This repository contains tests for a number of verification features in Verilator:

• concurrent assertions,
• functional coverage,
• randomization constraints,
• class parameters,
• sequences,

and more.

Usage

This repository contains several submodules that have their own submodules as well. In order to build properly, after cloning this repository, run the following command within the repository directory (not necessary if you use the scripts/build_and_run.sh script for executing the flow):

git submodule update --init --recursive

Or, you may clone the repository by running:

git clone --recursive

to avoid the need for recursive submodule update.

Requirements

To run these tests, you need Robot Framework, PyYAML, and Jinja2 installed on your system.

Build and run automatically

To automate the process, you can use act as a workflow tool. Even though it is practical to execute, this flow does not generate the reports within the local repository directory. If you want to run the workflow manually and get the report automatically, you must first build the tools manually. In order to do so through the provided build and run bash script, execute the command below when you are within the repository directory:

./scripts/build_and_run.sh {OPTIONAL_BUILD_OPTS}

This script runs the git initialization, Verilator builds, test generation, and test run. If you would like to run specific commands within the flow, you may examine .github/workflows/test.yml or scripts/build_and_run.sh. Running the script without any {OPTIONAL_BUILD_OPTS} would execute all the steps in the flow. Run the script with -help option to get more details on running specific steps within the flow.

./scripts/build_and_run.sh --help

Parse arguments and run individual steps

{OPTINONAL_BUILD_OPTS} are listed below:

• --setup Sets up the submodules within this repository recursively.
• --build {TARGET} Builds the TARGET Verilator branch. Using --build all builds all the Verilator targets within the repository.
• --gen-tests {TARGET} Generates tests to be run for the TARGET Verilator branches. Using --gen-tests all generates all the tests within the repository.
• --run-tests Runs the generated tests and generates the reports. [TBD] flags for this option.
• --help Lists the OPTINONAL_BUILD_OPTS of this script.

Manually generate and run tests

gen-tests is a script that generates Robot test files for each test in the tests directory. To generate and run all tests on an already-built environment, use:

./gen-tests

robot *.robot

All tests are divided into several test suites. The file branches.yml defines which suite is tested with which branch of Verilator. To generate tests for a specific branch of Verilator (e.g., randomize-constraints):

./gen-tests randomize-constraints

Multiple branches can be passed:

./gen-tests master randomize-constraints

Robot tests are generated from Jinja2 templates in the templates directory. While generating tests for a given test suite, a template with the same name as the test suite is used. If no such template exists, the default template is used.

The file tags.yml allows adding custom tags to specific tests.