Commit Graph

10 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
e2df847139 Adopt lemma as the default keyword
Convert every theorem to lemma (mathlib's default) except the headline results a
reader of each module seeks out: analyze_correct (Forward/Sign/Constant),
aFix_eq/aFix_le (Fixedpoint), trace (Language), and Stmt.cfg_sufficient
(Language/Properties). lemma and theorem are interchangeable keywords, so no
references change.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-25 14:08:10 -05:00
ec2e789d5c Spell out evalB as evalBasicStmt
Replace the ad-hoc truncation `evalB`/`evalB_mono` in
Spa/Analysis/Forward/Adapters.lean with `evalBasicStmt`/`evalBasicStmt_mono`.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-25 14:06:38 -05:00
5ac881559d Switch FiniteMap Fin n -> L representation
This helps automatically derive lattice laws for it

Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-25 14:05:59 -05:00
93f913a699 Clean up namespaces in the analysis framework
- Wrap the forward-analysis framework in a Spa.Forward namespace so its
  generic names (analyze, result, joinAll, variablesAt, ...) no longer
  sit flat in Spa, matching the ConstAnalysis/SignAnalysis convention.
- Merge the split Graph namespace in Graphs.lean by relocating buildCfg.
- Use nested namespace Spa / Fixedpoint instead of Spa.Fixedpoint.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-24 13:56:16 -05:00
ed88f4ce94 Use 'interp' to add [[ bla ]] notation for analysis
Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>
2026-06-23 13:29:54 -05:00
7f753a4f38 Delete more LLM-generated comments from the migration 2026-06-23 12:29:46 -05:00
2ee32580a2 Lean migration cleanup: collapse FixedHeight struct into FiniteHeightLattice typeclass
The fable-based migration left a two-layer design (a standalone `FixedHeight α h`
struct, height carried as a type index, plus a `FiniteHeightLattice` wrapper).
This collapses it to the single `FiniteHeightLattice` typeclass (height as a
plain field, `⊥`/`⊤` via `extends Bot`/`Top`), and fixes the fallout so the
whole project builds again (`lake build` green).

- Lattice: repair `FixedHeight.bot_le` (compute the `▸` motive via a forward
  `rw`, drop the leftover `fh.length_longestChain`) and the `bot_le` alias.
- Isomorphism: transport rewritten directly onto `FiniteHeightLattice`, taking
  the source as an instance argument.
- Lattice/Prod, AboveBelow: `FixedHeight`-producing def + wrapper instance
  collapsed into one `FiniteHeightLattice` instance. `head`/`last` proofs use
  term-mode `congrArg` to bridge the `Bot`/`Top` defeq through the
  under-construction instance projection (where `rw`+`rfl` cannot).
- Lattice/IterProd: `fixedHeight` recursion now yields a `FiniteHeightLattice`
  (no height index, so the `.cast (by ring)` reassociations vanish);
  `bot_fixedHeight` reprojected onto the def's own `.bot`.
- Lattice/FiniteMap: `fixedHeight`/`bot_contains_bots` go through transport with
  the IterProd instance resolved by typeclass search; `punitFixedHeight`
  replaced by the `PUnit` instance.
- Analysis/Forward/Lattices: `botV` uses `⊥` instead of the deleted
  `FiniteHeightLattice.bot` accessor.
- Analysis/Sign: `num` case used unimported `ring`; the goal is a pure ℕ→ℤ
  cast identity, closed with `norm_cast`. Also fixes the missing `show` in
  `AboveBelow.monotone₂_of_strict` that left un-beta-reduced redexes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-22 18:33:48 -05:00
b16f14fdfd Lean migration: typeclass-based parameter passing, as in the Agda original
The port had flattened Agda's instance arguments ({{flA}}, {{evaluator}},
{{latticeInterpretation}}, {{validEvaluator}}) into explicitly threaded
values (fhL, E, I, hE). Restore them as typeclasses:

- Spa.FiniteHeightLattice: now actually used — Fixedpoint takes the
  instance instead of a FixedHeight value; FiniteMap gets the missing
  instance (height = ks.length * height B), so varsFixedHeight /
  statesFixedHeight / signFixedHeight / constFixedHeight plumbing
  disappears (instance bottoms are defeq to the old ones)
- Spa.Analysis.Forward.Evaluation: StmtEvaluator/ExprEvaluator become
  classes; the Valid* Props become Prop-classes, as in Agda
- Spa.Analysis.Forward.Adapters: the expr→stmt adapter and its validity
  are instances (Agda: the ExprToStmtAdapter instances)
- LatticeInterpretation is a class; sign/const interpretations,
  evaluators and validity proofs are instances; use sites read like the
  Agda module applications: result SignLattice prog

Proof simplifications (same theorems, proofs factored):

- Spa.Lattice.AboveBelow.monotone₂_of_strict: any ⊥-strict/⊤-dominated
  operation on a flat lattice is monotone — replaces the four near-
  identical case bashes per analysis (postulates in Agda)
- Spa.Lattice.AboveBelow.interp_sup_of/interp_inf_of: the shared flat-
  lattice interpretation case analysis, making interpSign_sup/inf and
  interpConst_sup/inf one-liners

lake build green with zero warnings; lake exe spa output verified
byte-identical (diff) to the previous, Agda-verified output.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-09 23:32:38 -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