Phase 21.6 solidification: chain green (return/binop/loop/call); add Phase 21.7 normalization plan (methodize static boxes). Update CURRENT_TASK.md and docs.

docs/development/roadmap/phases/phase-21.6-solidification/CHECKLIST.md

@@ -6,16 +6,48 @@ Acceptance (all must be green on this host)
 - VM: MIR(JSON) for minimal loop returns 10
 - ny‑llvmc(crate) EXE: returns 10
 
+Canaries to run
+- bash tools/dev/stageb_loop_json_canary.sh
+- bash tools/dev/phase216_chain_canary.sh
+- bash tools/dev/phase216_chain_canary_return.sh
+- bash tools/dev/phase216_chain_canary_binop.sh
+- bash tools/dev/phase216_chain_canary_loop.sh
+- bash tools/dev/phase216_chain_canary_call.sh (Phase 21.6 extension)
+
 Guardrails
 - No default behavior changes; all aids behind env toggles.
 - Logs quiet; tags/dev traces are opt‑in.
 - No llvmlite in default chain; crate backend is main line.
 
-Canaries to run
-- bash tools/dev/stageb_loop_json_canary.sh
-- bash tools/dev/phase216_chain_canary.sh
-
 Rollback
 - Parser fallback in parse_loop is conservative; remove after VM/gpos fix lands.
 - Keep canaries; they protect against regressions.
 
+## Phase 21.6 Call Support Extension
+
+**Toggles**:
+- `HAKO_STAGEB_FUNC_SCAN=1`: Enable function definition scanning in Stage-B
+- `HAKO_MIR_BUILDER_FUNCS=1`: Enable function definition lowering in MirBuilder (unused - Rust delegate used)
+
+**Implementation**:
+1. Stage-B function scanner extracts `method <name>(params){ body }` definitions
+2. Stage-B injects `defs` array into Program(JSON v0)
+3. Rust delegate (src/runner/json_v0_bridge/) processes `defs` and generates MIR functions
+4. Function names are qualified as `Box.method` (e.g., `Main.add`)
+
+**Current Status**:
+- ✅ Stage-B scanning implemented (compiler_stageb.hako)
+- ✅ Rust delegate defs processing implemented (ast.rs, lowering.rs)
+- ✅ MIR functions generated with correct signatures and bodies
+- ⚠️  Call resolution incomplete: calls still use dynamic string lookup ("add") instead of static Main.add reference
+
+**Next Steps for Call Completion**:
+- Need to resolve Call("add") → Call(Main.add) at lowering time
+- Implement call target resolution in json_v0_bridge/lowering.rs
+- Update Call instruction to use function reference instead of string
+- Alternative: use MirCall with Callee::Function for local calls
+
+**撤去条件 (Removal Criteria)**:
+- After Phase 22 introduces proper local function scoping with Callee typed calls
+- Or when unified with broader namespace/using system Phase 15.5+
+

docs/development/roadmap/phases/phase-21.7-normalization/CHECKLIST.md

@@ -0,0 +1,20 @@
+Phase 21.7 — Normalization Checklist (Methodization)
+
+Targets (must be green)
+- Naming: all user functions canonicalized as Box.method/N
+- Arity: params.len == call.args.len (or explicit mapping when defs absent)
+- Methodization (dev toggle): Global("Box.method") → Method(receiver=static singleton)
+- VM: Method calls execute via ensure_static_box_instance for static boxes
+- LLVM: mir_call(Method) lowering produces correct IR; rc parity preserved
+
+Canaries
+- tools/dev/phase216_chain_canary_call.sh — remains PASS when OFF, PASS when ON
+- Add: tools/dev/phase217_methodize_canary.sh (dev) — asserts method callee usage in MIR or IR tags
+
+Toggles
+- HAKO_MIR_BUILDER_METHODIZE=1 (new)
+- HAKO_STAGEB_FUNC_SCAN=1 / HAKO_MIR_BUILDER_FUNCS=1 / HAKO_MIR_BUILDER_CALL_RESOLVE=1 (existing)
+
+Rollback
+- Disable HAKO_MIR_BUILDER_METHODIZE; remove methodization rewrite; keep Global path active.
+

docs/development/roadmap/phases/phase-21.7-normalization/README.md

@@ -0,0 +1,42 @@
+Phase 21.7 — Normalization & Unification (Methodize Static Boxes)
+
+Goal
+- Unify user-defined function calls onto a single, consistent representation.
+- Move from ad-hoc Global("Box.method") calls toward Method calls with an explicit (singleton) receiver when appropriate.
+- Keep defaults stable; introduce dev toggles and canaries; then promote to default after green.
+
+Scope
+- Parser/Stage‑B: keep emitting Program(JSON v0). No schema changes required for MVP.
+- MirBuilder: add methodization (dev toggle) that:
+  - Emits method functions as-is (defs) and/or provides a mapping to Method calls
+  - Rewrites Global("Box.method") to Method {receiver=static singleton, box_name, method}
+  - Preserves arity and naming as Box.method/N
+- VM: handle Method calls uniformly (receiver resolved via ensure_static_box_instance for static boxes).
+- LLVM: rely on mir_call(Method) lowering (already supported) and provide the static receiver where needed.
+
+Toggles
+- HAKO_MIR_BUILDER_METHODIZE=1 — enable methodization (rewrite Global→Method with static singleton receiver)
+- HAKO_STAGEB_FUNC_SCAN=1 — Stage‑B defs scan (already available)
+- HAKO_MIR_BUILDER_FUNCS=1 — defs→MIR 関数化（既存）
+- HAKO_MIR_BUILDER_CALL_RESOLVE=1 — Global 名解決（既存）
+
+Design Rules
+- Naming: canonical "Box.method/N". Arity N must equal params.len (or callsite args len if defs unknown).
+- Receiver: for static boxes, provide implicit singleton receiver. For instance boxes, preserve existing Method path.
+- Effects: preserve EffectMask semantics; do not broaden side effects.
+- Fail‑Fast: when rewrite is ambiguous (multiple candidates), keep original form and WARN under dev toggle; never change defaults silently.
+
+Acceptance
+- Canaries:
+  - call (global style) passes when methodization ON (rc unchanged)
+  - Existing return/binop/loop/call (global) canaries remain green when OFF
+  - A dedicated methodization canary asserts presence of callee.type=="Method" in MIR(JSON v1) or correct v0 lowering
+
+Rollout Plan
+1) Ship behind HAKO_MIR_BUILDER_METHODIZE=1 with canaries
+2) Validate on representative apps (selfhost‑first path)
+3) Promote to default ON only after green for a cycle; keep rollback instructions
+
+Rollback
+- Disable HAKO_MIR_BUILDER_METHODIZE. Revert to Global("Box.method") resolution path (current 21.6 behavior).
+