circt-nix

Package LLVM, MLIR, and CIRCT and related projects using nix + flakes.

Available packages:

• circt - CIRCT
• mlir - MLIR (built using LLVM version pinned by CIRCT)
• slang - SystemVerilog compiler and language services

For a list of all outputs, see nix flake show circt (after adding to registry, see below). Only x86_64-linux has been tested.

Built with assertions enabled.

Install

This requires nix, preferably with flake support. Flake support is assumed throughout, to use without flakes see Without Flakes.

Clone repository locally if you would like to make changes to it, but otherwise no installation required.

Cachix (use prebuilt paths)

Use the dtz-circt cachix to use prebuilt paths when available.

Follow the instructions at that link, or install cachix yourself and run cachix use dtz-circt.

Usage

Either refer to this flake as github:dtzSiFive/circt-nix, or optionally add this to your flake registry for simpler invocations:

$ nix registry add circt github:dtzSiFive/circt-nix

For brevity's sake, the remaining commands will assume this has been added to your registry, but if not use the longer reference.

Registry entries can be pinned with nix registry pin.

Build CIRCT

$ nix build circt
$ ./result/bin/firtool --help

Prebuilt versions may be available via cachix, but if not (or not using it) this will build LLVM, MLIR, and CIRCT (separately).

Install to profile

nix profile

nix profile is experimental, but works natively with flakes.

In addition to simpler installation procedure (of CIRCT), since nix profile tracks installation origin details, it's easy to upgrade your CIRCT installation when updates to this repository are made.

$ nix profile install circt

nix-env

See Without Flakes.

Development shell for working on CIRCT

This repo also provides a development shell for work on CIRCT.

To use:

$ nix develop circt

Or with nix-direnv:

$ echo "use flake circt" >> /path/to/circt-src/.envrc

So that the environment is automatically loaded/unloaded when cd'ing to that directory.

Without Flakes

Compatibility with non-flakes nix is provided for use with non-flakes tools, such as with nix-env.

Generally speaking, point the command at this repository usually with:

-f https://github.com/dtzSiFive/circt-nix/archive/master.tar.gz

Install to profile: nix-env

$ nix-env -f https://github.com/dtzSiFive/circt-nix/archive/master.tar.gz -iA default

nix-build

$ nix-build https://github.com/dtzSiFive/circt-nix/archive/master.tar.gz -A default

Maintainer

Will Dietz