LLVM Interpreter

A simple LLVM IR interpreter written in C++ that can execute LLVM bitcode. It supports a plugin system for implementing custom program analysis.

Features

• Executes LLVM IR (.ll files)
• Supports basic arithmetic, control flow, memory operations, and function calls
• Plugin system for custom program analysis

Limitations

This interpreter supports only a subset of LLVM instructions at the moment. Floating point operations, LLVM intrinsics etc, are currently not supported. I am working on adding support for these instructions.

Building

Prerequisites

• CMake 3.16 or higher
• LLVM 18+ with development headers

Build Steps

1. Clone or navigate to the project directory:

   cd /path/to/LLVM_Interpreter
   

2. Create a build directory:

   mkdir build
   cd build
   

3. Configure with CMake:

   cmake ..
   

4. Build the project:

   make
   

This will build:

• src/interpreter: Main interpreter executable
• plugin-example/plugin_example: Interpreter with logging plugin

Usage

Running the Interpreter

Execute an LLVM IR file:

./build/src/interpreter path/to/program.ll [args...]

Running with Logging Plugin

Execute with instruction logging:

./build/plugin-example/plugin_example path/to/program.ll [args...]

The logging plugin outputs [LOG] Executing instruction: ... for each executed instruction.

Test Files

The tests/ directory contains sample LLVM IR files:

• arithmetic_control.ll: Arithmetic and control flow operations
• arrays_pointers.ll: Array and pointer operations
• functions.ll: Function calls
• recursion.ll: Recursive functions

Example:

./build/plugin-example/plugin_example tests/arithmetic_control.ll

Project Structure

• include/: Header files
• src/: Source files and main CMakeLists.txt
• plugin-example/: Example plugin implementation
• tests/: Sample LLVM IR test files

Extending with Plugins

Implement the ExecutionPlugin interface to add custom functionality. See plugin-example/logging_plugin.hpp for an example.