compwocont.md 769B
Summarise Contribution & Motivation
- Both CPS and ANF inhibit some optimisations
- Aim to get benefits of both
- Extend direct-style lambda calculus by adding join points
- How to infer join points
- Join points can be recursive which gives new optimisation
- Show that approach works in GHC
Methodology
- Define new intermediate language Fj
- Perform single pass to find let bindings that are join points
- These are let bound functions that will never be captured in closure
- This is simpler than contification because they only look for tail calls
Critical Assessment
- Achieves big reduction in allocations for some programs
- Other programs lose out on potential optimisations
- Transformations can be applied broadly, even to call by value languages