IEC-ST-Analyzer

A Python tool for static analysis of IEC 61131-3 Structured Text (ST) code. It parses PLC logic into an XML Abstract Syntax Tree (AST) and generates Program Dependency Graphs (PDGs) and Invariant Templates for safety verification.

🚀 Capabilities

• ST Parser: Converts Structured Text source code into a standardized XML AST.
• Static Analysis: Builds Program Dependency Graphs (PDG) mapping control and data flow.
• Invariant Extraction: Automatically identifies safety invariant templates:
  • Single-Variable: H_Sensor > 100 -> Valve = FALSE
  • Multi-Variable: IF Sensor + Offset > Limit THEN Actuate
  • Inter-State: Logic governing valid state transitions.
• Variable Classification: Automatically detects Sensing, Actuation, and Configuration variables.

📦 Installation

Requires Python 3.13+.

Using uv (Recommended):

uv venv
source .venv/bin/activate
uv sync