cli: global --emit-mir-json early gate; selfhost: FlowEntryBox (emit-only) + FlowRunner (Mini‑VM); LocalSSA: after‑PHI materialize (ensure_calls/ensure_cond); harness: v1→v0 downgrade extern fallback; tools: build_and_run_wasm.sh; smokes: flow_runner + harness; docs: harness-first + CURRENT_TASK updates (drop tmp/*)

Author: nyash-codex

CURRENT_TASK_SELFHOST.md

@@ -36,7 +36,11 @@ Next actions
 - [x] Enable commit/push for selfhost branches (local hooks updated)
 - [x] PipelineV2: Apply LocalSSA.ensure_cond as final pass (fail‑safe)
 - [x] Add quick smokes for If(Compare) CFG and loop counter
- - [x] Verify Jump lowering and add docs pointers (quick/selfhost jump smokes; LLVM PHI harness smokes)
+- [x] Verify Jump lowering and add docs pointers (quick/selfhost jump smokes; LLVM PHI harness smokes)
+ - [x] v1→v0 downgrade extern fallback (harness‑only): unresolved Global → externcall when NYASH_LLVM_DOWNGRADE_V1=1
+   - Runner emit updated: src/runner/mir_json_emit.rs
+   - New smoke: tools/smokes/v2/profiles/quick/llvm/harness_v1_downgrade_global_extern_compile_ok.sh
+   - Fail‑Fast maintained for VM/AOT (unresolved Global → error)
 
 Phase 15.7 — NyKernel (Option B) minimal AOT step
 - [x] Introduce `crates/hako_kernel` minimal static shim (C‑ABI stubs)
@@ -63,3 +67,14 @@ Addendum — 2025‑10‑01 (late)
   - tools/smokes/v2/profiles/quick/selfhost/selfhost_pipeline_v2_method_exec_vm.sh
   - tools/smokes/v2/profiles/quick/selfhost/selfhost_pipeline_v2_newbox_exec_vm.sh
 - Stage‑1 extractors: hardened to accept negatives/whitespace; emitters now accept string‑form args (e.g., "[5, 7]") and materialize ints. Follow‑up: verify PipelineV2 call path end‑to‑end; boundary smoke will be enabled after confirming args materialization.
+
+Addendum — 2025‑10‑02
+- Runner/Flow minimal box化（emit-only入口＆VM実行ヘルパ）
+  - Added: `apps/selfhost-compiler/pipeline_v2/flow_entry.hako` (FlowEntryBox) — emit‑only entry, v0 / v1→v0 互換
+  - Added: `apps/selfhost/vm/flow_runner.hako` (FlowRunner) — FlowEntry→Mini‑VM 実行の薄い箱
+  - Mapped modules: `selfhost.compiler.pipeline_v2.flow_entry`, `selfhost.vm.flow_runner`（nyash.toml/hako.toml）
+  - New smoke: `tools/smokes/v2/profiles/quick/selfhost/selfhost_flow_runner_return_int_vm.sh`（Return(Int 42)→exec=42）
+- LocalSSA 材化ポリシー整理（PHI直後に統一）
+  - ensure_calls: 実装済（v0/v1のrecv/argsに対応）
+  - ensure_cond: ブロック先頭→PHI直後に変更（copy位置を統一）
+  - 既存 selfhost PipelineV2 smokesは NYASH_PIPELINE_V2=1 で回して緑を確認

apps/selfhost-compiler/builder/ssa/local.nyash

@@ -176,7 +176,7 @@ static box LocalSSA {
         cur = obj_end
         continue
       }
-      // Insert copy at the start of the block
+      // Insert copy after PHI cluster at block head
       // Trace: capture block id of this branch's block
       local bid = 0
       // Find nearest '"id":<n>' before this block's instructions
@@ -187,9 +187,22 @@ static box LocalSSA {
           if bid_csv == "" { bid_csv = "" + bid } else { bid_csv = bid_csv + "," + bid }
         }
       }
+      // Compute insertion point just after contiguous PHI nodes
+      local insert_at = insts_start
+      {
+        local scan = insts_start
+        loop(true) {
+          local pphi = me._index_of_from(out, "\"op\":\"phi\"", scan)
+          if pphi < 0 || pphi >= obj_start { break }
+          local sphi = me._seek_obj_start(out, pphi)
+          local ephi = me._seek_obj_end(out, sphi)
+          insert_at = ephi
+          scan = ephi
+        }
+      }
       local new_id = me._max_dst_id(out) + 1
       local copy_inst = "{\\\"op\\\":\\\"copy\\\",\\\"src\\\":" + digits + ",\\\"dst\\\":" + new_id + "},"
-      out = out.substring(0, insts_start) + copy_inst + out.substring(insts_start, out.length())
+      out = out.substring(0, insert_at) + copy_inst + out.substring(insert_at, out.length())
       t_copies = t_copies + 1
       // Rewrite branch cond to new_id within obj segment (adjust obj positions by insertion)
       local delta = copy_inst.length()
@@ -258,6 +271,249 @@ static box LocalSSA {
     return json_text
   }
 
+  // Experimental: call-site operand materialization (minimal)
+  // Insert copy instructions after the PHI cluster of a block when call/method/new operands
+  // (recv/args) are not defined earlier in the same block. This keeps operands locally materialized
+  // without changing semantics. JSON is manipulated textually to avoid adding heavy dependencies.
+  ensure_calls(json_text) {
+    if json_text == null { return json_text }
+    // Only operate on MIR(JSON) text; Stage‑1 remains unchanged
+    if me._is_mir_json(json_text) == 0 { return json_text }
+    local out = json_text
+    local cur = 0
+    loop(true) {
+      // Find next call-like instruction (v0 and v1 tolerant)
+      local p1 = me._index_of_from(out, "\"op\":\"call\"", cur)
+      local p2 = me._index_of_from(out, "\"op\":\"boxcall\"", cur)
+      local p3 = me._index_of_from(out, "\"op\":\"newbox\"", cur)
+      local p4 = me._index_of_from(out, "\"op\":\"mir_call\"", cur)
+      // choose earliest >=0
+      local op_pos = -1
+      local kind = 0 // 1=call,2=boxcall,3=newbox,4=mir_call
+      if p1 >= 0 { op_pos = p1  kind = 1 }
+      if p2 >= 0 && (op_pos < 0 || p2 < op_pos) { op_pos = p2  kind = 2 }
+      if p3 >= 0 && (op_pos < 0 || p3 < op_pos) { op_pos = p3  kind = 3 }
+      if p4 >= 0 && (op_pos < 0 || p4 < op_pos) { op_pos = p4  kind = 4 }
+      if op_pos < 0 { break }
+
+      // Determine instruction object and enclosing block bounds
+      local obj_start = me._seek_obj_start(out, op_pos)
+      local obj_end = me._seek_obj_end(out, obj_start)
+      local insts_start = me._block_insts_start(out, obj_start)
+      if insts_start < 0 { cur = obj_end  continue }
+
+      // Compute insertion point: after the contiguous PHI cluster at the block head
+      local insert_at = insts_start
+      local scan = insts_start
+      loop(true) {
+        local pphi = me._index_of_from(out, "\"op\":\"phi\"", scan)
+        if pphi < 0 || pphi >= obj_start { break }
+        local sphi = me._seek_obj_start(out, pphi)
+        local ephi = me._seek_obj_end(out, sphi)
+        insert_at = ephi
+        scan = ephi
+      }
+
+      // Inline helpers are expanded where needed（Nyash: avoid nested func capture for portability）
+
+      // V0: args array inside the instruction object
+      if kind == 1 || kind == 2 || kind == 3 {
+        // Receiver for boxcall
+        if kind == 2 {
+          local bk = "\"box\":"
+          local bp = me._index_of_from(out, bk, obj_start)
+          if bp >= 0 && bp < obj_end {
+            local digits = me._read_digits(out, bp + bk.length())
+            // Check if dst:<digits> exists before this instruction in the block
+            local has_def = 0
+            if digits != "" {
+              local def_pat = "\"dst\":" + digits
+              local s = insts_start
+              loop(true) {
+                local p = me._index_of_from(out, def_pat, s)
+                if p < 0 || p >= obj_start { break }
+                has_def = 1
+                break
+              }
+            }
+            if digits != "" && has_def == 0 {
+              // Insert copy and rewrite box id
+              local new_id = me._max_dst_id(out) + 1
+              local copy_inst = "{\\\"op\\\":\\\"copy\\\",\\\"src\\\":" + digits + ",\\\"dst\\\":" + new_id + "},"
+              out = out.substring(0, insert_at) + copy_inst + out.substring(insert_at, out.length())
+              local delta = copy_inst.length()
+              if insert_at <= obj_start { obj_start = obj_start + delta  obj_end = obj_end + delta }
+              // rewrite digits at bp
+              local head = out.substring(0, bp + bk.length())
+              local di = bp + bk.length()
+              loop(true) {
+                local ch = out.substring(di, di+1)
+                if ch >= "0" && ch <= "9" { di = di + 1 } else { break }
+              }
+              local tail = out.substring(di, out.length())
+              out = head + new_id + tail
+            }
+          }
+        }
+        // Args list
+        local ak = me._index_of_from(out, "\"args\":[", obj_start)
+        if ak >= 0 && ak < obj_end {
+          // find end of args list (first closing ']' after ak)
+          local i = ak + 8
+          local rb = i
+          loop(true) {
+            local ch = out.substring(i, i+1)
+            if ch == "]" || ch == "" { rb = i  break }
+            i = i + 1
+          }
+          // iterate over digits inside args
+          local pos = ak + 8
+          loop(pos < rb) {
+            local ch = out.substring(pos, pos+1)
+            if ch >= "0" && ch <= "9" {
+              local digits = me._read_digits(out, pos)
+              // materialize this operand if needed
+              if digits != "" {
+                // Check local def
+                local has_def = 0
+                local def_pat = "\"dst\":" + digits
+                local s = insts_start
+                loop(true) {
+                  local p = me._index_of_from(out, def_pat, s)
+                  if p < 0 || p >= obj_start { break }
+                  has_def = 1
+                  break
+                }
+                if has_def == 0 {
+                  local new_id = me._max_dst_id(out) + 1
+                  local copy_inst = "{\\\"op\\\":\\\"copy\\\",\\\"src\\\":" + digits + ",\\\"dst\\\":" + new_id + "},"
+                  out = out.substring(0, insert_at) + copy_inst + out.substring(insert_at, out.length())
+                  local delta = copy_inst.length()
+                  if insert_at <= obj_start { obj_start = obj_start + delta  obj_end = obj_end + delta }
+                  // rewrite occurrence inside [ak..rb)
+                  local head = out.substring(0, ak)
+                  local mid = out.substring(ak, rb)
+                  local q = mid.indexOf(digits)
+                  if q >= 0 {
+                    mid = mid.substring(0, q) + new_id + mid.substring(q + digits.length(), mid.length())
+                    out = head + mid + out.substring(rb, out.length())
+                    // recompute bounds
+                    insts_start = me._block_insts_start(out, obj_start)
+                    insert_at = insts_start
+                    scan = insts_start
+                    loop(true) {
+                      local pphi2 = me._index_of_from(out, "\"op\":\"phi\"", scan)
+                      if pphi2 < 0 || pphi2 >= obj_start { break }
+                      local sphi2 = me._seek_obj_start(out, pphi2)
+                      local ephi2 = me._seek_obj_end(out, sphi2)
+                      insert_at = ephi2
+                      scan = ephi2
+                    }
+                    // refresh rb & pos relative to new string
+                    rb = me._index_of_from(out, "]", ak + 8)
+                    if rb < 0 { rb = obj_end }
+                    pos = ak + 8
+                    continue
+                  }
+                }
+              }
+              // Move after this number (recompute rb due to potential rewrite)
+              rb = me._index_of_from(out, "]", ak + 8)
+              if rb < 0 { rb = obj_end }
+              pos = ak + 8
+              // advance to next non-digit to avoid infinite loop
+              loop(true) {
+                local c2 = out.substring(pos, pos+1)
+                if !(c2 >= "0" && c2 <= "9") { break }
+                pos = pos + 1
+              }
+            } else {
+              pos = pos + 1
+            }
+          }
+        }
+      } else {
+        // V1: mir_call has args in nested object
+        local mk = "\"mir_call\":{"
+        local mp = me._index_of_from(out, mk, obj_start)
+        if mp >= 0 && mp < obj_end {
+          local ak = me._index_of_from(out, "\"args\":[", mp)
+          if ak >= 0 && ak < obj_end {
+            local i = ak + 8
+            local rb = i
+            loop(true) {
+              local ch = out.substring(i, i+1)
+              if ch == "]" || ch == "" { rb = i  break }
+              i = i + 1
+            }
+            local pos = ak + 8
+            loop(pos < rb) {
+              local ch = out.substring(pos, pos+1)
+              if ch >= "0" && ch <= "9" {
+                local digits = me._read_digits(out, pos)
+                // materialize this operand if needed
+                if digits != "" {
+                  local has_def = 0
+                  local def_pat = "\"dst\":" + digits
+                  local s = insts_start
+                  loop(true) {
+                    local p = me._index_of_from(out, def_pat, s)
+                    if p < 0 || p >= obj_start { break }
+                    has_def = 1
+                    break
+                  }
+                  if has_def == 0 {
+                    local new_id = me._max_dst_id(out) + 1
+                    local copy_inst = "{\\\"op\\\":\\\"copy\\\",\\\"src\\\":" + digits + ",\\\"dst\\\":" + new_id + "},"
+                    out = out.substring(0, insert_at) + copy_inst + out.substring(insert_at, out.length())
+                    local delta = copy_inst.length()
+                    if insert_at <= obj_start { obj_start = obj_start + delta  obj_end = obj_end + delta }
+                    local head = out.substring(0, ak)
+                    local mid = out.substring(ak, rb)
+                    local q = mid.indexOf(digits)
+                    if q >= 0 {
+                      mid = mid.substring(0, q) + new_id + mid.substring(q + digits.length(), mid.length())
+                      out = head + mid + out.substring(rb, out.length())
+                      insts_start = me._block_insts_start(out, obj_start)
+                      insert_at = insts_start
+                      scan = insts_start
+                      loop(true) {
+                        local pphi2 = me._index_of_from(out, "\"op\":\"phi\"", scan)
+                        if pphi2 < 0 || pphi2 >= obj_start { break }
+                        local sphi2 = me._seek_obj_start(out, pphi2)
+                        local ephi2 = me._seek_obj_end(out, sphi2)
+                        insert_at = ephi2
+                        scan = ephi2
+                      }
+                      rb = me._index_of_from(out, "]", ak + 8)
+                      if rb < 0 { rb = obj_end }
+                      pos = ak + 8
+                      continue
+                    }
+                  }
+                }
+                rb = me._index_of_from(out, "]", ak + 8)
+                if rb < 0 { rb = obj_end }
+                pos = ak + 8
+                loop(true) {
+                  local c2 = out.substring(pos, pos+1)
+                  if !(c2 >= "0" && c2 <= "9") { break }
+                  pos = pos + 1
+                }
+              } else {
+                pos = pos + 1
+              }
+            }
+          }
+        }
+      }
+
+      // advance cursor beyond this instruction object
+      cur = obj_end
+    }
+    return out
+  }
+
   // --- Trace API (既定OFF) ---
   trace_enable(on) {
     if on { me._trace_on = 1 } else { me._trace_on = 0 }

apps/selfhost-compiler/pipeline_v2/README.md

@@ -6,6 +6,7 @@ Scope
 - No new capabilities or extern calls are introduced in Phase 15.7 (spec invariant).
 
 Boxes
+- FlowEntryBox (emit-only): entry to PipelineV2. Accepts Stage‑1 JSON and returns MIR(JSON).
 - ExecutionPipelineBox: orchestrates ParserBox → EmitterBox; optional BackendBox tag only.
 - BackendBox (stub): records backend name ("vm"|"llvm"|"pyvm"); no execution.
 - MirBuilderBox (stub/IF): future lowering and optimization entry (not wired in Phase 15.7).
@@ -20,6 +21,7 @@ Responsibilities
   - 既存の emit_mir_flow.hako は段階的に委譲→削減（互換維持）
   - Dev観測: `NYASH_EMIT_TRACE=1` を想定した最小トレース（現状は無条件1行出力。最終JSON行は変わらず）
 - Execute: delegated to Rust Runner (parent→child). This directory must NOT perform execution.
+  - Note: actual execution helper is provided under `apps/selfhost/vm/flow_runner.hako`.
 
 Non-goals (Phase 15.7)
 - No extern/FFI invocations to call backends from Ny code.
@@ -36,6 +38,14 @@ Tracing (dev)
   - `PipelineV2.lower_stage1_to_mir_trace(ast_json, prefer_cfg, trace)` — when `trace==1`, emit boxes print a single-line `[emit] ...` before JSON.
   - ExecutionPipelineBox は emit-only 経路であり、trace の布告は Runner 引数透過で後段導入予定（既定OFF）。
 
+JSON v1 (MirCall) — experimental
+- PipelineV2 provides an opt-in path to emit unified call form:
+  - `PipelineV2.lower_stage1_to_mir_v1(ast_json, prefer_cfg)` — emits op:`mir_call` with `callee` payload (Global/Method/Constructor) and `args` array.
+  - `PipelineV2.lower_stage1_to_mir_v1_compat(ast_json, prefer_cfg)` — emits v1 then adapts to legacy v0 (call/boxcall/newbox) via `selfhost.common.json.mir_v1_adapter`.
+- Notes
+  - Mini‑VM (MirVmMin) tolerates `op:"mir_call"` by treating its result as 0 (shape-only). Use the compat path to execute on MirVmMin.
+  - Default smokes remain on v0. Additional quick shape smokes exist under `tools/smokes/v2/profiles/quick/selfhost/*_v1_shape_vm.sh`.
+
 Fail-Fast
 - If parsing returns null/empty, print an error to stderr and return non-zero.
 - Do not print non-JSON lines when `NYASH_JSON_ONLY=1`.