Circuit IR Compilers and Tools

⚡️ “CIRCT” / Circuit IR Compilers and Tools

“CIRCT” stands for “Circuit IR Compilers and Tools”. One might also interpret it as the recursively as “CIRCT IR Compiler and Tools”. The T can be selectively expanded as Tool, Translator, Team, Technology, Target, Tree, Type, … we’re ok with the ambiguity.

The CIRCT community is an open and welcoming community. If you’d like to participate, you can do so in a number of different ways:

  1. Join our Discourse Forum on the LLVM Discourse server. To get a “mailing list” like experience click the bell icon in the upper right and switch to “Watching”. It is also helpful to go to your Discourse profile, then the “emails” tab, and check “Enable mailing list mode”.

  2. For real-time discussion join the CIRCT channel of the LLVM discord server.

  3. Join our weekly video chat. Please see the meeting notes document for more information.

  4. Contribute code. CIRCT follows all of the LLVM Policies: you can create pull requests for the CIRCT repository, and gain commit access using the standard LLVM policies .

Also take a look at the following diagram, which gives a brief overview of the current dialects and how they interact :


The EDA industry has well-known and widely used proprietary and open source tools. However, these tools are inconsistent, have usability concerns, and were not designed together into a common platform. Furthermore these tools are generally built with Verilog (also VHDL ) as the IRs that they interchange. Verilog has well known design issues, and limitations, e.g. suffering from poor location tracking support.

The CIRCT project is an (experimental!) effort looking to apply MLIR and the LLVM development methodology to the domain of hardware design tools. Many of us dream of having reusable infrastructure that is modular, uses library-based design techniques, is more consistent, and builds on the best practices in compiler infrastructure and compiler design techniques.

By working together, we hope that we can build a new center of gravity to draw contributions from the small (but enthusiastic!) community of people who work on open hardware tooling. In turn we hope this will propel open tools forward, enables new higher-level abstractions for hardware design, and perhaps some pieces may even be adopted by proprietary tools in time.

For more information, please see our longer charter document .

Nightly performance plots: