README.md


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```
yosys -- Yosys Open SYnthesis Suite

Copyright (C) 2012 - 2020  Claire Xenia Wolf <claire@yosyshq.com>

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
```


yosys – Yosys Open SYnthesis Suite
===================================

This is a framework for RTL synthesis tools. It currently has
extensive Verilog-2005 support and provides a basic set of
synthesis algorithms for various application domains.

Yosys can be adapted to perform any synthesis job by combining
the existing passes (algorithms) using synthesis scripts and
adding additional passes as needed by extending the yosys C++
code base.

Yosys is free software licensed under the ISC license (a GPL
compatible license that is similar in terms to the MIT license
or the 2-clause BSD license).


Web Site and Other Resources
============================

More information and documentation can be found on the Yosys web site:
- https://yosyshq.net/yosys/

The "Documentation" page on the web site contains links to more resources,
including a manual that even describes some of the Yosys internals:
- https://yosyshq.net/yosys/documentation.html

The directory `guidelines` contains additional information
for people interested in using the Yosys C++ APIs.

Users interested in formal verification might want to use the formal verification
front-end for Yosys, SymbiYosys:
- https://symbiyosys.readthedocs.io/en/latest/
- https://github.com/YosysHQ/SymbiYosys


Installation
============

Yosys is part of the [Tabby CAD Suite](https://www.yosyshq.com/tabby-cad-datasheet) and the [OSS CAD Suite](https://github.com/YosysHQ/oss-cad-suite-build)! The easiest way to use yosys is to install the binary software suite, which contains all required dependencies and related tools.

* [Contact YosysHQ](https://www.yosyshq.com/contact) for a [Tabby CAD Suite](https://www.yosyshq.com/tabby-cad-datasheet) Evaluation License and download link