Into the Core - Squeezing Haskell into Nine Constructors
summary
GHC compiles Haskell into a tiny statically typed intermediate language based on System F and ultimately expressed with only nine constructors, letting the compiler run a fast type checker after each transform. Concrete claims: let-floating, strictness analysis, specialization, inlining and case-of-case drive a cascade of local rewrites; cross-module interface .hi unfoldings enable aggressive inlining and fusion; a simplifier loop plus join-point handling reduces allocation and improves generated code.
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chapters (7)
- 0:00Haskell and GHC intro
- 10:13Core as GHC sanity check
- 24:44Optimization pipeline
- 36:21Let and lambda transforms
- 43:24Case expression optimizations
- 55:50Join points and strict core
- 1:05:29Q&A








