ci: add GitHub Actions workflow; runner: prefer PyVM in selfhost paths; stage3: add LLVM + bridge acceptance smokes; docs: update env flags

tools/ny_stage3_bridge_accept_smoke.sh

@@ -0,0 +1,60 @@
+#!/usr/bin/env bash
+set -euo pipefail
+[[ "${NYASH_CLI_VERBOSE:-0}" == "1" ]] && set -x
+
+ROOT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
+BIN="$ROOT_DIR/target/release/nyash"
+
+if [[ ! -x "$BIN" ]]; then
+  (cd "$ROOT_DIR" && cargo build --release >/dev/null)
+fi
+
+pass() { echo "✅ $1" >&2; }
+fail() { echo "❌ $1" >&2; echo "$2" >&2; exit 1; }
+
+run_json_expect_code() {
+  local name="$1"; shift
+  local json="$1"; shift
+  local expect_code="$1"; shift
+  set +e
+  # Feed JSON v0 directly via pipe. Prefer PyVM for parity.
+  OUT=$(printf '%s\n' "$json" | NYASH_PIPE_USE_PYVM=${NYASH_PIPE_USE_PYVM:-1} "$BIN" --ny-parser-pipe --backend vm 2>&1)
+  CODE=$?
+  set -e
+  if [[ "$CODE" == "$expect_code" ]]; then pass "$name"; else fail "$name" "$OUT"; fi
+}
+
+# A) try/catch/finally acceptance (degrade path unless NYASH_BRIDGE_TRY_ENABLE=1); final return 0
+JSON_A='{"version":0,"kind":"Program","body":[
+  {"type":"Try","try":[{"type":"Local","name":"x","expr":{"type":"Int","value":1}}],
+   "catches":[{"param":"e","typeHint":"Error","body":[{"type":"Local","name":"y","expr":{"type":"Int","value":2}}]}],
+   "finally":[{"type":"Local","name":"z","expr":{"type":"Int","value":3}}]
+  },
+  {"type":"Return","expr":{"type":"Int","value":0}}
+]}'
+run_json_expect_code "try/catch/finally (accept)" "$JSON_A" 0
+
+# B) break acceptance under dead branch (ignored when not in loop)
+JSON_B='{"version":0,"kind":"Program","body":[
+  {"type":"If","cond":{"type":"Bool","value":false},"then":[{"type":"Break"}]},
+  {"type":"Return","expr":{"type":"Int","value":0}}
+]}'
+run_json_expect_code "break in dead branch (accept)" "$JSON_B" 0
+
+# C) continue acceptance under dead branch (ignored when not in loop)
+JSON_C='{"version":0,"kind":"Program","body":[
+  {"type":"If","cond":{"type":"Bool","value":false},"then":[{"type":"Continue"}]},
+  {"type":"Return","expr":{"type":"Int","value":0}}
+]}'
+run_json_expect_code "continue in dead branch (accept)" "$JSON_C" 0
+
+# D) throw acceptance as expression (degrade path unless NYASH_BRIDGE_THROW_ENABLE=1)
+JSON_D='{"version":0,"kind":"Program","body":[
+  {"type":"Expr","expr":{"type":"Throw","expr":{"type":"Int","value":123}}},
+  {"type":"Return","expr":{"type":"Int","value":0}}
+]}'
+run_json_expect_code "throw (accept)" "$JSON_D" 0
+
+echo "All Stage-3 bridge acceptance smokes PASS" >&2
+exit 0
+

tools/selfhost_stage2_smoke.sh

@@ -12,6 +12,10 @@ fi
 TMP="$ROOT_DIR/tmp"
 mkdir -p "$TMP"
 
+# Default to PyVM reference unless explicitly disabled by caller
+: "${NYASH_VM_USE_PY:=1}"
+export NYASH_VM_USE_PY
+
 pass() { echo "✅ $1" >&2; }
 fail() { echo "❌ $1" >&2; echo "$2" >&2; exit 1; }
 

tools/smokes/curated_llvm_stage3.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Curated LLVM Stage-3 acceptance smoke (llvmlite harness)
+# Usage: tools/smokes/curated_llvm_stage3.sh [--phi-off]
+
+ROOT_DIR=$(cd "$(dirname "$0")/../.." && pwd)
+BIN="$ROOT_DIR/target/release/nyash"
+
+if ! [ -x "$BIN" ]; then
+  echo "[curated-llvm-stage3] building nyash (release, features=llvm)" >&2
+  cargo build --release --features llvm >/dev/null
+fi
+
+export NYASH_LLVM_USE_HARNESS=1
+
+if [[ "${1:-}" == "--phi-off" ]]; then
+  export NYASH_MIR_NO_PHI=1
+  export NYASH_VERIFY_ALLOW_NO_PHI=1
+  echo "[curated-llvm-stage3] PHI-off (edge-copy) enabled" >&2
+fi
+
+run_ok() {
+  local path="$1"
+  echo "[curated-llvm-stage3] RUN --backend llvm: ${path}"
+  timeout 10s "$BIN" --backend llvm "$path" >/dev/null
+}
+
+# A) try/catch/finally without actual throw
+run_ok "$ROOT_DIR/apps/tests/stage3_try_finally_basic.nyash"
+
+# B) throw in dead branch (acceptance only)
+run_ok "$ROOT_DIR/apps/tests/stage3_throw_dead_branch.nyash"
+
+# C) repeat with trap disabled (robustness; should be no-op here)
+NYASH_LLVM_TRAP_ON_THROW=0 run_ok "$ROOT_DIR/apps/tests/stage3_try_finally_basic.nyash"
+NYASH_LLVM_TRAP_ON_THROW=0 run_ok "$ROOT_DIR/apps/tests/stage3_throw_dead_branch.nyash"
+
+echo "[curated-llvm-stage3] OK"
+