Proove Mark&Sweep GC with Coq
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This document discusses Coq GC (garbage collection). It provides an overview of Coq and how it can be used to formally prove properties of a garbage collector. It presents the definition of a Mem record to represent memory state and definitions for MarkPhase and Safety properties. It also discusses implementing mark phase in OCaml and proving it is correct using Coq.
![• GC
• (Safety)[1]
[1]Burdy Gemplus Avenue , L. Burdy “B vs. Coq to prove
a Garbage Collector” 2001
11](https://image.slidesharecdn.com/gc-100808024524-phpapp01/85/Proove-Mark-Sweep-GC-with-Coq-11-320.jpg)
Proove Mark&Sweep GC with Coq
- 1. Coq GC id:mzp 2010-08-08 GC 1
- 2. • : • http://twitter.com/mzp • http://d.hatena.ne.jp/mzp/ • : SE • Coq 2
- 3. : GC • • : • : 2010(c) nari3 3
- 4. 4
- 6. M&S • • • 6
- 7. Coq 7
- 8. Coq • • • 8
- 9. Coq (1) • • OCaml,Haskell,Scheme • 9
- 10. Coq (2) • • Twitter reply • Coq 20 10
- 11. • GC • (Safety)[1] [1]Burdy Gemplus Avenue , L. Burdy “B vs. Coq to prove a Garbage Collector” 2001 11
- 12. • • • “ ” Record Mem {A : Type} := mkMem { nodes : set A; roots : set A; frees : set A; next : A -> option A; marker : A -> mark; }. 12
- 13. GC • • : (* m1 m2 *) Definition MarkPhase (m1 m2 : Mem) : Prop := roots m1 = roots m2 ∧ nodes m1 = nodes m2 ∧ frees m1 = frees m2 ∧ next m1 = next m2 ∧ Included (closuresM m2) (marksM Marked m2). (* ⊆ *) : ( ) 13
- 14. • • Safety Lemma MarkPhase_Safety:∀(m1 m2: Mem), MarkPhase m1 m2 -> (* m1 m2 *) Safety m1 -> (* m1 Safety *) Safety m2 ∧ MarksAll m2. (* m2 Safety *) Safety ( ) 14
- 15. • • OCaml Definition mark_phase (m : Mem) : Mem := mkMem A (nodes m) (roots m)(frees m) (fun x => if In_dec x (closuresM m) then Marked else Unmarked) (next m). ( ) 15
- 16. • • Lemma mark_phase_correct: ∀ m1 m2, m2 = mark_phase m1 -> MarkPhase m1 m2. ( ) 16
- 17. • OCaml • OCaml • GC GC GC 17
- 18. ... • Coq - Coq • 8/29 13:00 @ • http://atnd.org/events/6022 18
- 19. • • Burdy Gemplus Avenue , L. Burdy “B vs. Coq to prove a Garbage Collector” 2001 19