hakorune/docs/development/current/main/phases/phase-130

Phase 130: if-only Normalized “Small Expr/Assign” Expansion (dev-only)

Status: PLAN (P0–P3) Scope: if-only Normalized（StepTree → Normalized shadow pipeline） Related:

• Entry: docs/development/current/main/10-Now.md
• Phase 129 (join_k/post_k): docs/development/current/main/phases/phase-129/README.md
• ControlTree SSOT: docs/development/current/main/design/control-tree.md

Goal

Increase usefulness of the if-only Normalized path without touching loop lowering yet:

• Enable minimal post-if computation (x = x + 3) and returns via env.
• Keep PHI禁止: merge via env + continuations only.
• Keep dev-only and 既定挙動不変: unmatched shapes fall back (strict can Fail-Fast for fixtures).

Non-Goals

• No loops (Loop/Break/Continue still rejected by capability guard).
• No general expression lowering (start with one narrow shape only).
• No new env vars (use existing joinir_dev_enabled() / joinir_strict_enabled()).

Work Items (P0–P3)

P0: Fixtures + Smokes (VM + LLVM EXE)

Add a “post-if update then return” fixture that forces post_k to execute and tests env updates:

• New fixture: apps/tests/phase130_if_only_post_if_add_min.hako
  • Case A: flag=1 → expected 5
  • Case B: flag=0 → expected 4
  • Output: 5\n4
• Smokes (integration):
  • tools/smokes/v2/profiles/integration/apps/phase130_if_only_post_if_add_vm.sh
  • tools/smokes/v2/profiles/integration/apps/phase130_if_only_post_if_add_llvm_exe.sh
  • Use output_validator.sh numeric-line assertion.
  • LLVM EXE smoke uses llvm_exe_runner.sh + plugin gating.

Acceptance:

• phase130_*_vm.sh PASS
• phase130_*_llvm_exe.sh PASS (SKIP allowed only if LLVM prerequisites missing; plugin prerequisites should be satisfied via existing runner)

P1: Assign(Variable) minimal

Support x = y inside post_k (and/or inside branches) for if-only:

• Only local variables (no field/property assign).
• RHS must resolve from env (writes or inputs).
• strict: unsupported shapes → freeze_with_hint("phase130/assign/var/unsupported", ...).

P2: Assign(Add) minimal for integers

Support x = x + <int literal> (exact shape) in post_k:

• Strictly Var + IntLiteral with lhs_var == dst_var (no commutation, no general binop).
• Type: integer only (string concat stays out-of-scope; Fail-Fast under strict).

P3: Verifier tightening (env writes-only discipline)

Add a structural check to ensure env updates only target writes fields:

• In Normalized emission, any “env update” must update a field that exists in EnvLayout.writes.
• Writing to an inputs field is prohibited (strict Fail-Fast).

Verification

Commands:

cargo test --lib

# New Phase 130 smokes
bash tools/smokes/v2/profiles/integration/apps/phase130_if_only_post_if_add_vm.sh
bash tools/smokes/v2/profiles/integration/apps/phase130_if_only_post_if_add_llvm_exe.sh

# Regressions (minimum)
bash tools/smokes/v2/profiles/integration/apps/phase129_if_only_post_if_return_var_vm.sh
bash tools/smokes/v2/profiles/integration/apps/phase129_join_k_as_last_vm.sh
bash tools/smokes/v2/profiles/integration/apps/phase128_if_only_partial_assign_normalized_vm.sh

Notes

• Phase 130 intentionally stays “if-only” to keep the change-set small and correctness-focused.
• Loop lowering in Normalized is a separate phase; do not mix scopes.