macro(if normalize): switch to ControlFlowBuilder for If stmt construction; llvm: add PHI hygiene smoke for If cases

tools/test/smoke/llvm/ir_phi_hygiene_ifcases.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+root=$(cd "$(dirname "$0")"/../../../.. && pwd)
+bin="$root/target/release/nyash"
+
+if [ ! -x "$bin" ]; then
+  echo "nyash binary not found at $bin; build first (cargo build --release --features llvm)" >&2
+  exit 1
+fi
+
+export NYASH_MACRO_ENABLE=1
+export NYASH_MACRO_PATHS="apps/macros/examples/if_match_normalize_macro.nyash"
+export NYASH_LLVM_USE_HARNESS=1
+
+fails=0
+
+check_case() {
+  local src="$1"
+  local irfile="$root/tmp/$(basename "$src" .nyash)_llvm.ll"
+  mkdir -p "$root/tmp"
+  NYASH_LLVM_DUMP_IR="$irfile" "$bin" --backend llvm "$src" >/dev/null 2>&1 || {
+    echo "[FAIL] LLVM run failed for $src" >&2
+    fails=$((fails+1))
+    return
+  }
+  if [ ! -s "$irfile" ]; then
+    echo "[FAIL] IR not dumped for $src" >&2
+    fails=$((fails+1))
+    return
+  }
+  local empty_cnt
+  empty_cnt=$(rg -n "\\bphi\\b" "$irfile" | rg -v "\\[" | wc -l | tr -d ' ')
+  if [ "${empty_cnt:-0}" != "0" ]; then
+    echo "[FAIL] Empty PHI detected in $irfile" >&2
+    rg -n "\\bphi\\b" "$irfile" | rg -v "\\[" || true
+    fails=$((fails+1))
+    return
+  fi
+  echo "[OK] PHI hygiene (no empty PHI): $(basename "$irfile")"
+}
+
+check_case "apps/tests/macro_golden_if_assign.nyash"
+check_case "apps/tests/macro_golden_if_print.nyash"
+
+if [ "$fails" -ne 0 ]; then
+  exit 2
+fi
+echo "[OK] LLVM PHI hygiene for If-cases passed"
+exit 0
+