CS 6120: Advanced Compilers

The Self-Guided Online Experience (2020 Edition)

Developed by Adrian Sampson, CS 6120 is a Cornell PhD-level computer science course centered on the implementation of programming languages.

The curriculum balances "universal" compiler fundamentals—such as data flow, intermediate representations (IR), and traditional optimizations—with cutting-edge research topics, including garbage collection, just-in-time (JIT) compilation, and parallelization.

🎓 Course Logistics

This version of the course is designed for students attending the University of Your Imagination.

Credit Value: 4 Imagination Credits (Ungraded)

The learning path is a linear sequence of lessons paired with academic papers. Each module typically includes:

• Instructional videos
• Comprehensive written notes
• Practical implementation exercises

These tasks are intentionally open-ended; they are designed to bridge the gap between $\text{Abstract Theory} \rightarrow \text{Concrete Code}$.

🛠️ Tools of the Trade

Students will engage in open-source hacking using:

1. LLVM (The industry standard)
2. Bril (A specialized educational IR created specifically for this course)

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⚖️ Self-Guided vs. Official Course

While based on the official Cornell offering, there are a few key distinctions:

Feature	Official CS 6120	Self-Guided Version
Deadlines	Strict	Strict Flexible
Communication	Zulip Discussion Threads	Independent Study
Final Project	Semester-end Project	Change the world via compilers

Note: The instructor admits to being a "video production neophyte," so please overlook the quality of the early recordings.

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🗺️ Learning Roadmap

📚 Detailed Curriculum

Phase 1: Foundations

• Lesson 1: Welcome
  • Video: Overview
  • Reading: "Producing Wrong Data Without Doing Anything Obviously Wrong!"
  • Reading: SIGPLAN Empirical Evaluation Guidelines
• Lesson 2: Representing Programs
  • Focus: How programs are modeled; getting started with Bril.
• Lesson 3: Local Analysis Optimization
  • Topics: Local Value Numbering, Simple Dead Code Elimination.

Phase 2: Analysis & Optimization

• Lesson 4: Data Flow
  • Activity: Implementation task.
• Lesson 5: Global Analysis
  • Focus: Global optimization.
  • Reading: "Efficient Path Profiling" (Ball & James R.).
• Lesson 6: Static Single Assignment (SSA)
  • Reading: "Provably Correct Peephole Optimizations with Alive" (Nuno P.).

Phase 3: The LLVM Ecosystem

• Lesson 7: LLVM
  • Focus: Introduction to the framework and authoring an LLVM pass.
• Lesson 8: Loop Optimization
  • Resource: Video lecture.
• Lesson 9: Interprocedural Analysis
  • Resource: Video lecture.
  • Reading: "Type-Based Alias Analysis" (Diwan, et al.).

Phase 4: Memory & Runtime

• Lesson 10: Alias Analysis
  • Resource: Video lecture.
  • Reading: "A Unified Theory of Garbage Collection" (David F.).
  • Reading: "Fast Conservative Garbage Collection" (Shahriyar & Stephen M.).
• Lesson 11: Memory Management
  • Resource: Video lecture.
  • Reading: "An Efficient Implementation of SELF..." (C. et al.).
  • Reading: "Trace-Based Just-in-Time Type Specialization for Dynamic Languages" (Gal, Eich, et al.).

Phase 5: Advanced Topics

• Lesson 12: Dynamic Compilers
  • Topics: Tracing via Speculation.
  • Reading: "Superoptimizer: A Look at the Smallest Program" (Alexia Massalin).
  • Reading: "Chlorophyll: Synthesis-Aided Compiler for Low-Power Spatial Architectures" (Phothilimthana, et al.).
• Lesson 13: Concurrency & Parallelism
  • Resource: Video lecture.
  • Reading: "Threads Cannot Be Implemented as a Library" (Hans-J.).
  • Reading: "Exploiting Superword Level Parallelism with Multimedia Instruction Sets" (Larsen & Amarasinghe).
  • Reading: "A Type and Effect System for Deterministic Parallel Java" (Adve, et al.).

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🛠️ Contribution & Feedback

Since CS 6120 is open source, you can find the materials on GitHub. If you encounter an error in the code or notes, please submit a bug report.

Final Step: Once you have completed your journey, please provide your thoughts via the feedback form.

# Example: How to start your journey
git clone https://github.com/adriansampson/cs6120.git
cd cs6120
echo "Time to change the world!"