CIRCT Python Bindings

1.145.1 verified Mon Apr 27 auth: no python

CIRCT (Circuit IR Compilers and Tools) Python bindings for interacting with MLIR-based hardware compilation tools. Current version 1.145.1. Released roughly monthly.

pip install circt

Common errors

error ImportError: cannot import name 'Module' from 'circt' ↓

cause Module is in circt.ir, not top-level.

fix

Use 'from circt.ir import Module'.

error RuntimeError: Cannot create context: another context is already active ↓

cause Multiple Context instances without proper cleanup.

fix

Use 'with Context():' block to ensure single active context.

Warnings

breaking CIRCT uses MLIR's Python bindings with breaking changes across versions. Ensure circt version matches the MLIR version used. ↓

fix Pin circt version in requirements.txt and check with MLIR version.

deprecated The 'circt.support' module is deprecated; use 'circt.ir' directly. ↓

fix Replace imports from circt.support with circt.ir.

gotcha Context creation is mandatory before any IR operations; forgetting leads to cryptic errors. ↓

fix Always use 'with circt.ir.Context() as ctx:' block.

Imports

circt
wrong
```
import circt.ir
```
correct
```
import circt
```
Submodules are accessed via circt.ir, circt.dialect, etc., not direct import.

Module

wrong

from circt import Module

correct

from circt.ir import Module

Module is in circt.ir, not top-level.

Quickstart

Create and print an MLIR module using CIRCT's IR bindings.

import circt
from circt.ir import Context, Location, Module

with Context() as ctx:
    loc = Location.unknown(ctx)
    module = Module.parse(ctx, '''
module {
  func.func @main() -> i32 {
    %0 = arith.constant 42 : i32
    return %0 : i32
  }
}
''')
    print(module)