Compilers translate one language to another. They're most commonly used to translate higher level languages like C to lower level languages like Assembly.

Compiler codebases to study Garbage Collection Algorithms – Dmitry Soshnikov Tracing JIT vs Method JIT: What to choose? : ProgrammingLanguages

To Review

• CS 6120 :: Advanced compilers course. Lots of cool things to learn about optimisation!
• Implementing functional languages: a tutorial - Microsoft Research
• Compilers - Compilers for contrarians
• MLton: A whole program optimizer for SML. OCaml has far more support, sure, but the prospect of a whole-program optimizer is compelling!

HOPL

Papers released every ten or so years recapping advancements in programming languages from that decade. Great resource for learning about the history of programming languages research by definition.

Example: HOPL IV: The history of programming languages.