LLM Understanding of Intermediate Representations

Published:

Project Overview

This research project investigates the capabilities of Large Language Models (LLMs) in understanding Intermediate Representations (IRs), which are essential in compiler design and program analysis. The study addresses a critical gap in our understanding of how modern AI models handle low-level code representations.

Research Objectives

  • IR Comprehension Analysis: Evaluate LLM understanding of IR syntax and semantics
  • Task Performance Assessment: Test LLMs across four critical IR-related tasks
  • Model Comparison: Analyze performance differences between various LLM architectures
  • Enhancement Recommendations: Propose improvements for IR-specific LLM capabilities

Methodology

  • Models Tested: GPT-4, GPT-3, Gemma 2, LLaMA 3.1, and Code Llama
  • Evaluation Tasks: Control Flow Graph (CFG) reconstruction, decompilation, code summarization, and execution reasoning
  • Analysis Framework: Comprehensive empirical study with structured evaluation metrics
  • IR Dataset: Diverse Intermediate Representation samples for testing

Key Findings

  • Strengths: LLMs demonstrate competence in parsing IR syntax and recognizing high-level structures
  • Limitations: Struggle with control flow reasoning, execution semantics, and loop handling
  • Common Errors: Misinterpretation of branching instructions, omission of critical IR operations
  • Reasoning Patterns: Heavy reliance on heuristic-based reasoning rather than deep understanding

Research Impact

This study provides foundational insights into LLM capabilities for compiler-level tasks and program analysis, with implications for:

  • AI-assisted compiler development
  • Program analysis automation
  • LLM training for low-level code understanding
  • Integration of AI in software engineering tools

Technical Contributions

  • Novel evaluation framework for IR comprehension
  • Comprehensive analysis of LLM limitations in IR tasks
  • Specific recommendations for IR-specific LLM enhancements
  • Framework for future research in AI-driven program analysis

Future Directions

The research identifies several areas for improvement:

  • IR-specific fine-tuning on structured datasets
  • Integration of explicit control flow models
  • Enhanced training on compiler-level tasks
  • Development of specialized IR understanding models

Publication

This work has been published as an arXiv preprint: "Can Large Language Models Understand Intermediate Representations?"