rage against annotate_predecessor

Transcript

1. RubyKaigi 2025 follow up ANDPAD Inc. 2025/08/30(Sat.) rage against annotate_predecessor Junichi Kobayashi (@junk0612) ESM, Inc.
2. 自己紹介 Junichi Kobayashi • X / GitHub: @junk0612 • Working at ESM, Inc. ◦ Work as a Rails engineer ◦ A Member of Parser Club • Committer of Lrama • Hobbies ◦ Parsers ◦ Rhythm games ◦ Board games ◦ Haiku
6. ✦ Optimize IELR calculation ✦ Introduce IELR to CRuby and make parse.y better Future Work
7. Optimize IELR Calculation $ time bundle exec lrama -D lr.type=ielr parse.y 69.02s user 0.29s system 99% cpu 1:09.38 total
8. Optimize IELR Calculation $ time bundle exec lrama -D lr.type=ielr parse.y 69.02s user 0.29s system 99% cpu 1:09.38 total $ time bundle exec lrama -D lr.type=ielr parse.y 11.51s user 0.26s system 82% cpu 14.193 total
9. Optimize IELR Calculation $ time bundle exec lrama -D lr.type=ielr parse.y 69.02s user 0.29s system 99% cpu 1:09.38 total $ time bundle exec lrama -D lr.type=ielr parse.y 11.51s user 0.26s system 82% cpu 14.193 total 6x Faster !!!
11. LA LR IELR
12. LA LR IELR annotate_predecessor
14. LALR IELR
15. LALR IELR annotate_predecessor
16. LALR IELR annotate_predecessor LALR IELR ←annotate_predecessor
17. annotate_predecessor
18. annotate_predecessor
19. s s' s'' t C': kernels Γ: Conflicted Actions C: kernels γ: Contribution Matrix (Size: [|Γ|][|C'|]) For each action 1≦i≦Γ and kernel item 1≦j≦C', γ[i][j] is true iff C'[j] may contribute token t into Γ[i]'s lookahead set at state s''.
20. s s' s'' t C': kernels Γ: Conflicted Actions C: kernels γ: Contribution Matrix (Size: [|Γ|][|C'|]) For each action 1≦i≦Γ and kernel item 1≦j≦C', γ[i][j] is true iff C'[j] may contribute token t into Γ[i]'s lookahead set at state s''. annotate_predecessor
21. The Naive Implementation class State def annotate_predecessor(predecessor) @annotation_list.each do |annotation| annotation.actions.each do |action| @kernels.each do |kernel| predecessor.kernels.each do |pred_kernel| ...
23. annotate_predecessor
24. s s' s'' t C': kernels Γ: Conflicted Actions C: kernels γ: Contribution Matrix (Size: [|Γ|][|C'|]) For each action 1≦i≦Γ and kernel item 1≦j≦C', γ[i][j] is true iff C'[j] may contribute token t into Γ[i]'s lookahead set at state s''. annotate_predecessor
25. Lanes • A: 'a' 'a'・, ['a', 'b'] • A: 'a'・, ['a', 'b'] • A: 'a'・'a', ['a', 'b'] a
26. Cache Lanes class State def annotate_predecessor(predecessor) @annotation_list.each do |annotation| annotation.actions.each do |action| @lane_items.each do |pred_kernel, kernel| ...
27. Cache Lanes $ time bundle exec lrama -D lr.type=ielr parse.y 69.02s user 0.29s system 99% cpu 1:09.38 total $ time bundle exec lrama -D lr.type=ielr parse.y 24.02s user 0.25s system 108% cpu 22.275 total
32. Cache Lanes $ time bundle exec lrama -D lr.type=ielr parse.y 24.02s user 0.29s system 99% cpu 1:09.38 total $ time bundle exec lrama -D lr.type=ielr parse.y 11.51s user 0.26s system 82% cpu 14.193 total
34. ✦ Optimize IELR calculation ✦ Introduce IELR to CRuby and make parse.y better Future Work
35. ✦ Optimize IELR calculation ✦ Introduce IELR to CRuby and make parse.y better ← ??? Future Work
37. [do, do_cond, do_block do_LAMBDA]
38. [do, do_cond, do_block, do_LAMBDA]
39. ✦ Tokens in the same group are temporarily equivalent for IELR ✦ If token paths differ, detect it as an Inadequacy Annotation Token Group
40. 👶