Class Tu/Th 12:30 - 1:50 p.m. in DH 2105
Recitation F 1:00 - 1:50 p.m. in GHC 4211
btitzer at andrew dot cmu dot edu
Office hours: Wednesday 3-5pm (or by appointment)
For appointments outside of office hours, email the instructor.
aldrich at cs dot cmu dot edu
Office hours: Thursday 5-6pm (or by appointment)
For appointments outside of office hours, email the instructor.
This course provides a broad and pragmatic foundation in the most basic tool of the programmer: programming languages. It starts with the fundamentals of syntax, parsing, and binding, the core structural concepts in programming languages. The course will then cover program semantics and type systems, and students will learn to relate them with a type soundness theorem. Finally, a coverage of intermediate optimization and code generation offers the opportunity to discuss both producing efficient code and reasoning about the correctness of program transformations. Assignments involve a combination of tool-assisted formal reasoning and proofs about programming languages, and implementing these language constructs in a compiler.
Prerequisites. Programming maturity and knowledge of reasoning about programs equivalent to passing 15-150, and mathematical maturity equivalent to passing either 15-251 or 21-228). Students with substantial math and programming experience who have not satisfied the specific prerequisites can contact the instructor for permission to enroll.
Requirements Satisfied.This course fulfills the Logic and Languages constrained elective category for the Computer Science major.
Why take this course?
- Programming Languages and Compilers are fundamental to programming, and you can learn about both in one course. By understanding the semantics of languages, you become a better programmer. After understanding how languages are compiled, you will be able to use them better. And it's not unlikely that you'll need to design a little language yourself someday--a scripting language or configuration for your application, for example--so it's good to know how to do it well!
- Learn the theory of languages, with the help of an educational tool. Programming language semantics and type theory is beautiful and fundamental not only to programming but even to the foundations of mathematics. While it sometimes has a reputation for being inaccessible, I've designed a tool called SASyLF that is easy to use and helps you get your proofs right. It's been used successfully at several universities--students like it and we believe it helps make these topics easier and more rewarding!
- Our pragmatic approach positions language and compiler concepts in the setting of industrial languages. We'll cover foundational ideas like the lambda calculus, but we understand that many students want to apply those ideas to languages familiar to them. This course will focus on covering fundamental ideas as they come up in widely-used languages, both making the ideas concrete and also ensuring that what you learn is relevant to your career as a computer scientist or software developer.
How does this course compare to CMU's other PL/compilers courses?
First of all, CMU has an amazing selection of courses in this area-you can't go wrong! But this course has some differences that make it a particularly great match for some students:
- Compared to 15-411 Compiler Design, this course involves less programming and more proofs (this is true of all Logic and Languages courses, since learning about rigorous proofs is one of the goals of the category). It gives up some depth specifically on compilation, but in exchange includes more programming language and type system content. And don't worry, half of the assignments are programming-you'll still build a compiler!
Course Syllabus and PoliciesThe syllabus covers course learning objectives, supplemental textbooks, assessments, late work policy, and policies.
|Date||Topic and Slides||Additional Reading or Code||Assignments Due|
|Aug 29||Course introduction||PLP, chapter 1|
|Aug 31||Syntax and Lexical Analysis||PLP, chapter 2 through 2.2; in-class exercise||HW0: Warmup|
|Sep 1||RecitationImplementing lexical analysis|
|Sep 5||Parsing preview | Binding||PLP, chapter 3; in-class exercise|
|Sep 7||Inductive definitions and proofs||04-formal.pdf; in-class exercise||HW1: Lexical analysis|
|Sep 8||RecitationThe SASyLF Proof Assistant||04-formal-sasylf.pdf|
|Sep 12||Dynamic semantics: Big-step||lecture05-big-step.pdf; in-class exercise|
|Sep 14||Dynamic semantics: Small-step||small-step.pdf; in-class exercise||HW2: Inductive proofs|
|Sep 15||RecitationDynamic semantics practice|
|Sep 19||Top-Down Parsing||PLP section 2.3; in-class exercise|
|Sep 21||Bottom-Up Parsing||in-class exercise and reference sheet||HW3: Dynamic Semantics|
|Sep 22||RecitationParsing implementation|
|Sep 26||Typing rules||09-typing.pdf; in-class exercise|
|Sep 28||Type Soundness||10-soundness.pdf; in-class exercise||HW4 checkpoint|
|Sep 29||RecitationStatic Semantics practice|
|Oct 3||Type Checking||PLP chapter 7|
|Oct 5||Composite Types||PLP Chapter 8||HW4: Parsing|
|Oct 6||RecitationStatic semantics practice|
|Oct 10||Mid-semester exam 1|
|Oct 12||Semantics of Objects||PLP chapter 10; Featherweight Java paper|
|Oct 13||RecitationMidterm discussion||HW5: Static semantics|
|Oct 24||Implementation of Objects||PLP chapter 10; in-class exercise|
|Oct 26||Implementing Functional Programming||Notes; in-class exercise||HW6 checkpoint|
|Oct 31||Intermediate representations and WebAssembly||PLP chapter 15;||HW6: Typechecking|
|Nov 2||Garbage collection||Notes on garbage collection|
|Nov 3||Recitation Code generation practice|
|Nov 7||Democracy Day - No class|
|Nov 9||Local Optimization and Correctness||PLP chapter 17; Notes on Optimization Correctness; in-class exercise||HW7 checkpoint|
|Nov 10||Recitation Optimization and correctness practice|
|Nov 14||Global Optimization||in-class exercise||HW7: Code generation|
|Nov 16||Register Allocation and Instruction Scheduling||in-class exercise|
|Nov 17||RecitationProject discussion|
|Nov 21||Loop optimizations (notes)||in-class exercise||HW8: Translation correctness, Project Proposal|
|Nov 23||No class - Thanksgiving break|
|Nov 24||No Recitation - Thanksgiving break|
|Nov 28||Control Flow||PLP chapters 6 and 9; in-class exercise|
|Nov 30||The Curry-Howard Isomorphism||in-class exercise|
|Dec 1||Recitation2nd midterm review|
|Dec 5||Midterm exam 2|
|Dec 7||Programming languages and compilers research|
|Dec 8||Recitation2nd midterm post-review|
|TBD (finals week)||Project presentations||Project presentations and final deliverables|