Commit Graph

11 Commits

Author SHA1 Message Date
b6b30958aa Add proof of reaching definition analysis
This requires a few pieces:

* Make node tags use `Fin n` intead of natural numbers. This makes
  it possible to build a finite lattice over AST nodes, and also
  ensure automatic, total indexing from CFG nodes into the AST that
  created them. For this, use the elaborator to derive the ordering
  statements etc. where possible.
* Adjust the forward framework to enable proofs that don't just state
  correctness on the environment, but also on an arbitrary additional
  state accumulated from traversing the trace.
* State the reaching definition analysis's correctness in terms
  of this new framework.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-27 18:56:59 -05:00
a5f533d67a Use a direct N-way unzip instead of induction over product size
This makes a finite-height proof for any `Fin n -> a` lattice
immediate, and precludes the need for IterProd and Prod altogether.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-26 12:16:04 -05:00
352e0bb8cc Fold Isomorphism module into Lattice.lean
Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>
2026-06-26 12:16:04 -05:00
94278a6389 Add computational reaching-definitions analysis
Introduce a finite-height lattice instance for Bool, then build the
reaching-definitions analysis on top of the forward framework:

* Spa/Lattice/Bool.lean: FiniteHeightLattice Bool (the two-element
  lattice false ≤ true), making FiniteMap A Bool ks a finite-height
  "power set" lattice for free.
* Spa/Analysis/Reaching.lean: DefSet prog = FiniteMap prog.State Bool
  prog.states as the per-variable lattice of definition sites, with a
  StmtEvaluator whose transfer function performs a strong update
  (assignment to k at node s sets k's def-set to {s}).

The analysis computes a least fixed point and produces correct
reaching-definitions sets. Soundness (relating def-sets to actual
execution provenance) is deferred; not yet exposed in Spa.lean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-25 09:12:11 -05:00
f23705a93e Add scoped quotation syntax for object-language programs
Introduce [spa_e| ... ] for Expr and [spa| ... ] for Stmt, scoped to the
Spa namespace via a dedicated syntax category and macro_rules. This removes
the deeply nested .andThen / .basic (.assign ...) boilerplate when writing
programs; Main.lean's test programs are rewritten to use it.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-23 15:11:34 -05:00
a82d54666a Lean migration: Phase 7 (Sign + Constant analyses, executable)
- Spa.Showable: port of Showable.agda (quoted strings, map format) for
  output parity
- Spa.Analysis.Utils: eval_combine₂
- Spa.Lattice.AboveBelow.le_cases: order of the flat lattice by cases
- Spa.Analysis.Sign / Spa.Analysis.Constant: the four monotonicity
  POSTULATES from the Agda files are now proved theorems (via le_cases);
  interpretations, evaluator validity, analyze_correct per analysis
- Main + lake exe spa: runs both analyses on the Agda test program;
  constant analysis folds unknown=0, sign analysis gives unknown=⊤

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 20:52:08 -07:00
739fbb503c Lean migration: Phase 6 (forward analysis framework)
- Spa.Analysis.Forward.Lattices: VariableValues/StateVariables (FiniteMap
  instantiations), fixed heights, variablesAt, joinForKey/joinAll, interpV
  and its sup/foldr lemmas
- Spa.Analysis.Forward.Evaluation: StmtEvaluator/ExprEvaluator + validity
  (the Agda Valid* instance records become plain Props)
- Spa.Analysis.Forward.Adapters: expr-to-stmt evaluator adapter + validity
- Spa.Analysis.Forward: updateAll, analyze, result (least fixpoint via the
  gas-based Fixedpoint), walkTrace, analyze_correct — the framework's main
  soundness theorem

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 20:14:53 -07:00
2cfd0a2fb7 Lean migration: Phase 5 (language, CFGs, traces, Program)
- Spa.Language.Base: Expr/BasicStmt/Stmt + HasVar relations; StringSet
  lifts to Finset String
- Spa.Language.Semantics: Value/Env/Env.Mem, big-step relations,
  LatticeInterpretation (respects-≈ field drops out with =)
- Spa.Language.Graphs: Graph with nodes : Fin size → List BasicStmt
  (Vec lookup lemmas lift to Fin.append_left/right), comp/link/loop/
  skipto/singleton/wrap/buildCfg, predecessors via List.finRange
- Spa.Language.Traces: Trace + EndToEndTrace (Prop-valued)
- Spa.Language.Properties: trace embeddings, loop lemmas,
  buildCfg_sufficient; the 80-line Fin-disjointness block reduces to
  castAdd_ne_natAdd + mathlib list lemmas
- Spa.Language: Program (vars via Finset.sort — toList is noncomputable)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 19:30:42 -07:00
781d7947e0 Lean migration: Phase 4 (IterProd + FiniteMap lattices)
- Spa.Lattice.IterProd: k-fold product, recursive Lattice instance,
  fixed height k*hA + hB, bot = build of bottoms
- Spa.Lattice.FiniteMap: spine-pinned assoc lists ({l // l.map fst = ks});
  with = the 1100-line Map.agda collapses into positional 'combine'.
  Same lemma inventory (membership, locate, updating, GeneralizedUpdate,
  valuesAt, Provenance-union, le_of_mem_mem) — Nodup is now an explicit
  hypothesis where the Agda Map carried it intrinsically. Fixed height
  |ks|*hB still via transport along the IterProd isomorphism, which no
  longer needs Unique ks (representation is canonical).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 19:12:39 -07:00
4c337afa9c Lean migration: Phase 3 (Unit, Prod, AboveBelow lattices)
- Spa.Lattice.Unit: PUnit fixed height 0 (lattice lifted from mathlib)
- Spa.Lattice.Prod: chain unzip + FixedHeight (h1+h2) on products
  (componentwise lattice lifted from mathlib's Prod.instLattice)
- Spa.Lattice.AboveBelow: flat lattice via Lattice.mk' (mirrors the Agda
  semilattices+absorption construction), boundedness via rank into Nat,
  Plain x ↦ plainFixedHeight x, height 2

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 18:48:02 -07:00
ae030386b4 Lean migration: Phases 0-2 (core lattice/chain, fixpoint, transport)
- lean/ lake project pinned to Lean v4.17.0 + mathlib v4.17.0
- Spa.Lattice: fold monotonicity, FixedHeight/BoundedChains (LTSeries-based),
  FiniteHeightLattice, chain-bottom-is-least; the rest of Lattice.agda,
  Chain.agda and Equivalence.agda lift into mathlib (see LEAN_MIGRATION.md)
- Spa.Fixedpoint: gas-based least-fixpoint computation (doStep/fix/aFix)
- Spa.Isomorphism: FixedHeight transport along monotone inverse pairs

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 18:36:43 -07:00