YJIT: Dive into Ruby's JIT compiler written in Rust / Rust.Tokyo 2022

Rust.Tokyo 2022

Transcript

1. YJIT: Dive into Ruby's JIT compiler written in Rust @k0kubun / Rust.Tokyo 2022
2. Me • @k0kubun • Shopify ◦ YJIT team • Ruby committer ◦ MJIT maintainer
3. What’s YJIT?
8. How does YJIT work?
9. How YJIT works Ruby code
10. How YJIT works 1 + 2 Parse Ruby code Abstract Syntax Tree
11. How YJIT works 1 + 2 Parse Ruby code Abstract Syntax Tree putobject 1 putobject 2 opt_plus leave Compile Bytecode
12. How YJIT works 1 + 2 Parse Ruby code Abstract Syntax Tree putobject 1 putobject 2 opt_plus leave Compile JIT Bytecode Machine code
13. How YJIT works putobject 1 putobject 2 opt_plus leave JIT ? Machine code Bytecode
14. How YJIT works: Ruby 3.1 putobject 1 putobject 2 opt_plus leave x86_64 Codegen Machine code Bytecode
15. How YJIT works: Ruby 3.2 putobject 1 putobject 2 opt_plus leave Machine code Bytecode
16. How YJIT works: Ruby 3.2 putobject 1 putobject 2 opt_plus leave Machine code Bytecode
17. Lazy Basic Block Versioning
18. Lazily compile basic blocks
19. getlocal a getlocal b opt_plus setlocal c getlocal c putobject 1 opt_gt branchunless getlocal a leave getlocal b leave Lazily compile basic blocks
20. Lazily compile basic blocks
21. getlocal a getlocal b opt_plus setlocal c getlocal c putobject 1 opt_gt branchunless Branch stub Branch stub Lazily compile basic blocks
22. getlocal a getlocal b opt_plus setlocal c getlocal c putobject 1 opt_gt branchunless getlocal a leave Branch stub Lazily compile basic blocks
23. getlocal a getlocal b opt_plus setlocal c getlocal c putobject 1 opt_gt branchunless getlocal a leave Branch stub Lazily compile basic blocks
24. getlocal a getlocal b opt_plus setlocal c getlocal c putobject 1 opt_gt branchunless getlocal a leave getlocal b leave Lazily compile basic blocks
25. Why lazy compilation? 1. Better code locality a. Only compile used paths b. Related code is put together
26. Why lazy compilation? 1. Better code locality a. Only compile used paths b. Related code is put together 2. More type information
27. Type Profiling
28. Type Profiling getlocal a getlocal b opt_plus
29. Type Profiling getlocal a getlocal b opt_plus
30. Type Profiling getlocal a getlocal b jmp regenerate
31. Type Profiling getlocal a getlocal b jmp regenerate
32. Type Profiling getlocal a getlocal b jmp regenerate a: 1 b: 2
33. Type Profiling getlocal a getlocal b opt_plus (int) setlocal c getlocal c putobject 1 opt_gt branchunless
34. Passes • CodeGen -> Split -> Alloc Regs
35. Passes • CodeGen -> Split -> Alloc Regs
36. IR
37. IR Split
38. IR Split Alloc Regs
39. Rust Challenges
40. Clang and Bindgen Clang dependency or Per-architecture codegen?
41. Mutable Borrow
42. Next steps • Code GC • Register allocation • Method inlining
43. Conclusion • We reviewed the architecture of YJIT • Rust has been useful for transforming IR