Circular Dependency of imports

[vmgeorgeTT]

NeoSim error on the branch :
ImportError: cannot import name 'valueStatus' from 'ttsim.back.tensix_neo.isaFunctions'

[jajuTT]

Text generated with help of AI:

Circular Import Dependency Analysis

We have run into a circular import chain causing the ImportError when attempting to import valueStatus from isaFunctions. Here's the complete import cycle:

Import Chain

1. tneoSim.py (line 13) -> imports isaFunctions
2. isaFunctions.py (line 15) -> imports ttsim.front.llk.instructions
3. Python encounters ttsim/front/__init__.py (executed when importing from the package)
4. ttsim/front/__init__.py (line 4) -> imports onnx2graph from .onnx.onnx2nx
5. onnx2nx.py (line 11) -> imports WorkloadGraph from ttsim.graph
6. ttsim/graph/__init__.py (line 8) -> imports wl_graph.WorkloadGraph
7. wl_graph.py (line 17) -> imports Device from ttsim.back.device
8. device.py (line 14) -> imports tneoSim (Circle closes - back to step 1)

The Problem

When device.py tries to import tneoSim, Python returns the partially initialized module from step 1. Execution then continues through the rest of the import chain, eventually reaching tensixFunc.py, which tries to import valueStatus from isaFunctions. However, isaFunctions hasn't finished executing yet (it's stuck at line 15 waiting for the chain to complete), so valueStatus is not yet defined.

Root Cause

The eager import in ttsim/front/__init__.py triggers the circular dependency. The __init__.py file automatically executes when importing anything from the ttsim.front package, forcing the import of onnx2graph even though it's not needed for accessing ttsim.front.llk.instructions.

Proposed Solutions

1. Remove/comment the eager import in ttsim/front/__init__.py (line 4)
2. Use lazy imports in isaFunctions.py - move the import inside functions where it's used
3. Refactor to break the cycle - extract shared dependencies into a separate module

[vmgeorgeTT]

@ssapreTT - Do you think proposed solution 1 is a possibility ?

[ssapreTT]

The circular dependency is being triggered at a rather deep level. We need to start by removing the eager import (solution 1), but the overall solution might not be complete there. We might need to also do part of 2 and / or 3.