📚 Phase 11 documentation: Everything is Box × MIR15 revolution

Key updates:
- Document MIR 26→15 instruction reduction plan (transitioning status)
- Add Core-15 target instruction set in INSTRUCTION_SET.md
- Save AI conference analyses validating Box Theory and 15-instruction design
- Create MIR annotation system proposal for optimization hints
- Update SKIP_PHASE_10_DECISION.md with LLVM direct migration rationale

Technical insights:
- RefNew/RefGet/RefSet can be eliminated through Box unification
- GC/sync/async all achievable with 15 core instructions
- BoxCall lowering can automatically insert GC barriers
- 2-3x performance improvement expected with LLVM
- Build time reduction 50%, binary size reduction 40%

Status: Design complete, implementation pending

tools/build_aot.sh

@@ -44,11 +44,10 @@ if ! cargo build --release --features cranelift-jit >/dev/null; then
   exit 1
 fi
 
-echo "[2/4] Emitting object (.o) via JIT (Strict/No-fallback) ..."
+echo "[2/4] Emitting object (.o) via JIT (Strict/No-fallback, jit-direct) ..."
 rm -rf target/aot_objects && mkdir -p target/aot_objects
 NYASH_AOT_OBJECT_OUT=target/aot_objects \
 NYASH_USE_PLUGIN_BUILTINS=1 \
-NYASH_JIT_EXEC=1 \
 NYASH_JIT_ONLY=1 \
 NYASH_JIT_STRICT=1 \
 NYASH_JIT_NATIVE_F64=1 \
@@ -56,13 +55,13 @@ NYASH_JIT_NATIVE_F64=1 \
 NYASH_JIT_PLUGIN_F64="${NYASH_JIT_PLUGIN_F64:-41:2}" \
 NYASH_JIT_ARGS_HANDLE_ONLY=1 \
 NYASH_JIT_THRESHOLD=1 \
-./target/release/nyash --backend vm "$INPUT" >/dev/null || true
+./target/release/nyash --jit-direct "$INPUT" >/dev/null || true
 
 OBJ="target/aot_objects/main.o"
 if [[ ! -f "$OBJ" ]]; then
   echo "error: object not generated: $OBJ" >&2
   echo "hint: Strict mode forbids fallback. Ensure main() is lowerable under current JIT coverage." >&2
-  echo "hint: Try a simpler RO example first, or expand JIT coverage for used ops." >&2
+  echo "hint: Try running jit-direct manually with envs above to see details." >&2
   exit 2
 fi
 

tools/mir15_smoke.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# MIR15 coverage smoke for VM + JIT (direct)
+# Usage: tools/mir15_smoke.sh [debug|release]
+
+MODE=${1:-release}
+BIN=./target/${MODE}/nyash
+
+echo "[smoke] building nyash (${MODE}, cranelift-jit)..." >&2
+cargo build --features cranelift-jit -q ${MODE:+--${MODE}}
+
+run_vm() {
+  local file="$1"
+  echo "[VM] $file" >&2
+  NYASH_VM_STATS=1 "$BIN" --backend vm "$file" >/dev/null || {
+    echo "[VM] FAILED: $file" >&2; exit 1; }
+}
+
+run_jit_direct() {
+  local file="$1"
+  echo "[JIT-DIRECT] $file" >&2
+  NYASH_JIT_EVENTS_COMPILE=1 NYASH_JIT_DUMP=1 NYASH_JIT_HOSTCALL=1 NYASH_JIT_THRESHOLD=1 \
+    "$BIN" --jit-direct "$file" >/dev/null || {
+    echo "[JIT] FAILED: $file" >&2; exit 1; }
+}
+
+run_jit_direct_optional() {
+  local file="$1"
+  echo "[JIT-DIRECT] $file (optional)" >&2
+  NYASH_JIT_EVENTS_COMPILE=1 NYASH_JIT_DUMP=1 NYASH_JIT_HOSTCALL=1 NYASH_JIT_THRESHOLD=1 \
+    "$BIN" --jit-direct "$file" >/dev/null || {
+    echo "[JIT] expected fallback: $file" >&2; return 0; }
+}
+
+echo "[smoke] VM core samples" >&2
+run_vm examples/include_main.nyash         # Const/Return
+run_vm examples/jit_branch_demo.nyash      # Branch/Jump/Phi path (via VM)
+run_vm examples/console_demo_simple.nyash  # ExternCall(env.console.log)
+
+echo "[smoke] JIT-direct Core-1" >&2
+run_jit_direct examples/jit_arith.nyash                     # BinOp
+run_jit_direct examples/jit_compare_i64_boolret.nyash       # Compare/bool ret
+run_jit_direct examples/jit_direct_local_store_load.nyash   # Load/Store (local slots)
+run_jit_direct examples/jit_branch_demo.nyash               # Branch/Jump/PHI(min)
+
+echo "[smoke] JIT-direct hostcalls (handle-based)" >&2
+run_jit_direct_optional examples/jit_array_is_empty.nyash            # any.isEmpty (optional)
+run_jit_direct_optional examples/jit_hostcall_array_append.nyash     # array.push (optional)
+run_jit_direct_optional examples/jit_map_get_param_hh.nyash          # map.get (optional)
+
+echo "[smoke] OK" >&2