infinite_recursive_call_check(Node* node, ScanEnv* env, int head)
{
  int ret;
  int r = 0;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
    {
      Node *x;
      OnigLen min;

      x = node;
      do {
        ret = infinite_recursive_call_check(NODE_CAR(x), env, head);
        if (ret < 0 || (ret & RECURSION_INFINITE) != 0) return ret;
        r |= ret;
        if (head != 0) {
          min = tree_min_len(NODE_CAR(x), env);
          if (min != 0) head = 0;
        }
      } while (IS_NOT_NULL(x = NODE_CDR(x)));
    }
    break;

  case NODE_ALT:
    {
      int must;

      must = RECURSION_MUST;
      do {
        ret = infinite_recursive_call_check(NODE_CAR(node), env, head);
        if (ret < 0 || (ret & RECURSION_INFINITE) != 0) return ret;

        r    |= (ret & RECURSION_EXIST);
        must &= ret;
      } while (IS_NOT_NULL(node = NODE_CDR(node)));
      r |= must;
    }
    break;

  case NODE_QUANT:
    r = infinite_recursive_call_check(NODE_BODY(node), env, head);
    if (r < 0) return r;
    if ((r & RECURSION_MUST) != 0) {
      if (QUANT_(node)->lower == 0)
        r &= ~RECURSION_MUST;
    }
    break;

  case NODE_ANCHOR:
    if (! ANCHOR_HAS_BODY(ANCHOR_(node)))
      break;
    /* fall */
  case NODE_CALL:
    r = infinite_recursive_call_check(NODE_BODY(node), env, head);
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      if (en->type == ENCLOSURE_MEMORY) {
        if (NODE_IS_MARK2(node))
          return 0;
        else if (NODE_IS_MARK1(node))
          return (head == 0 ? RECURSION_EXIST | RECURSION_MUST
                  : RECURSION_EXIST | RECURSION_MUST | RECURSION_INFINITE);
        else {
          NODE_STATUS_ADD(node, MARK2);
          r = infinite_recursive_call_check(NODE_BODY(node), env, head);
          NODE_STATUS_REMOVE(node, MARK2);
        }
      }
      else if (en->type == ENCLOSURE_IF_ELSE) {
        int eret;

        ret = infinite_recursive_call_check(NODE_BODY(node), env, head);
        if (ret < 0 || (ret & RECURSION_INFINITE) != 0) return ret;
        r |= ret;
        if (IS_NOT_NULL(en->te.Then)) {
          OnigLen min;
          if (head != 0) {
            min = tree_min_len(NODE_BODY(node), env);
          }
          else min = 0;

          ret = infinite_recursive_call_check(en->te.Then, env, min != 0 ? 0:head);
          if (ret < 0 || (ret & RECURSION_INFINITE) != 0) return ret;
          r |= ret;
        }
        if (IS_NOT_NULL(en->te.Else)) {
          eret = infinite_recursive_call_check(en->te.Else, env, head);
          if (eret < 0 || (eret & RECURSION_INFINITE) != 0) return eret;
          r |= (eret & RECURSION_EXIST);
          if ((eret & RECURSION_MUST) == 0)
            r &= ~RECURSION_MUST;
        }
      }
      else {
        r = infinite_recursive_call_check(NODE_BODY(node), env, head);
      }
    }
    break;

  default:
    break;
  }

  return r;
}


print_optimize_info(FILE* f, regex_t* reg)
{
  static const char* on[] = { "NONE", "EXACT",
                              "EXACT_FAST", "EXACT_FAST_STEP_FORWARD",
                              "EXACT_IC", "MAP" };

  fprintf(f, "optimize: %s\n", on[reg->optimize]);
  fprintf(f, "  anchor: "); print_anchor(f, reg->anchor);
  if ((reg->anchor & ANCHOR_END_BUF_MASK) != 0)
    print_distance_range(f, reg->anchor_dmin, reg->anchor_dmax);
  fprintf(f, "\n");

  if (reg->optimize) {
    fprintf(f, "  sub anchor: "); print_anchor(f, reg->sub_anchor);
    fprintf(f, "\n");
  }
  fprintf(f, "\n");

  if (reg->exact) {
    UChar *p;
    fprintf(f, "exact: [");
    for (p = reg->exact; p < reg->exact_end; p++) {
      fputc(*p, f);
    }
    fprintf(f, "]: length: %ld\n", (reg->exact_end - reg->exact));
  }
  else if (reg->optimize & OPTIMIZE_MAP) {
    int c, i, n = 0;

    for (i = 0; i < ONIG_CHAR_TABLE_SIZE; i++)
      if (reg->map[i]) n++;

    fprintf(f, "map: n=%d\n", n);
    if (n > 0) {
      c = 0;
      fputc('[', f);
      for (i = 0; i < ONIG_CHAR_TABLE_SIZE; i++) {
        if (reg->map[i] != 0) {
          if (c > 0)  fputs(", ", f);
          c++;
          if (ONIGENC_MBC_MAXLEN(reg->enc) == 1 &&
              ONIGENC_IS_CODE_PRINT(reg->enc, (OnigCodePoint )i))
            fputc(i, f);
          else
            fprintf(f, "%d", i);
        }
      }
      fprintf(f, "]\n");
    }
  }
}

don't expand string case folds to alternatives if code length == 1 and byte length is same


tree_min_len(Node* node, ScanEnv* env)
{
  OnigLen len;
  OnigLen tmin;

  len = 0;
  switch (NODE_TYPE(node)) {
  case NODE_BACKREF:
    if (! NODE_IS_CHECKER(node)) {
      int i;
      int* backs;
      MemEnv* mem_env = SCANENV_MEMENV(env);
      BackRefNode* br = BACKREF_(node);
      if (NODE_IS_RECURSION(node)) break;

      backs = BACKREFS_P(br);
      len = tree_min_len(mem_env[backs[0]].node, env);
      for (i = 1; i < br->back_num; i++) {
        tmin = tree_min_len(mem_env[backs[i]].node, env);
        if (len > tmin) len = tmin;
      }
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    {
      Node* t = NODE_BODY(node);
      if (NODE_IS_RECURSION(node)) {
        if (NODE_IS_MIN_FIXED(t))
          len = ENCLOSURE_(t)->min_len;
      }
      else
        len = tree_min_len(t, env);
    }
    break;
#endif

  case NODE_LIST:
    do {
      tmin = tree_min_len(NODE_CAR(node), env);
      len = distance_add(len, tmin);
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_ALT:
    {
      Node *x, *y;
      y = node;
      do {
        x = NODE_CAR(y);
        tmin = tree_min_len(x, env);
        if (y == node) len = tmin;
        else if (len > tmin) len = tmin;
      } while (IS_NOT_NULL(y = NODE_CDR(y)));
    }
    break;

  case NODE_STRING:
    {
      StrNode* sn = STR_(node);
      len = (int )(sn->end - sn->s);
    }
    break;

  case NODE_CTYPE:
  case NODE_CCLASS:
    len = ONIGENC_MBC_MINLEN(env->enc);
    break;

  case NODE_QUANT:
    {
      QuantNode* qn = QUANT_(node);

      if (qn->lower > 0) {
        len = tree_min_len(NODE_BODY(node), env);
        len = distance_multiply(len, qn->lower);
      }
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);
      switch (en->type) {
      case ENCLOSURE_MEMORY:
        if (NODE_IS_MIN_FIXED(node))
          len = en->min_len;
        else {
          if (NODE_IS_MARK1(node))
            len = 0;  /* recursive */
          else {
            NODE_STATUS_ADD(node, MARK1);
            len = tree_min_len(NODE_BODY(node), env);
            NODE_STATUS_REMOVE(node, MARK1);

            en->min_len = len;
            NODE_STATUS_ADD(node, MIN_FIXED);
          }
        }
        break;

      case ENCLOSURE_OPTION:
      case ENCLOSURE_STOP_BACKTRACK:
        len = tree_min_len(NODE_BODY(node), env);
        break;
      case ENCLOSURE_IF_ELSE:
        {
          OnigLen elen;

          len = tree_min_len(NODE_BODY(node), env);
          if (IS_NOT_NULL(en->te.Then))
            len += tree_min_len(en->te.Then, env);
          if (IS_NOT_NULL(en->te.Else))
            elen = tree_min_len(en->te.Else, env);
          else elen = 0;

          if (elen < len) len = elen;
        }
        break;
      }
    }
    break;

  case NODE_GIMMICK:
    {
      GimmickNode* g = GIMMICK_(node);
      if (g->type == GIMMICK_FAIL) {
        len = INFINITE_LEN;
        break;
      }
    }
    /* fall */
  case NODE_ANCHOR:
  default:
    break;
  }

  return len;
}


is_equal_mml(MinMax* a, MinMax* b)
{
  return a->min == b->min && a->max == b->max;
}


onig_new(regex_t** reg, const UChar* pattern, const UChar* pattern_end,
         OnigOptionType option, OnigEncoding enc, OnigSyntaxType* syntax,
         OnigErrorInfo* einfo)
{
  int r;

  *reg = (regex_t* )xmalloc(sizeof(regex_t));
  if (IS_NULL(*reg)) return ONIGERR_MEMORY;

  r = onig_reg_init(*reg, option, ONIGENC_CASE_FOLD_DEFAULT, enc, syntax);
  if (r != 0) goto err;

  r = onig_compile(*reg, pattern, pattern_end, einfo);
  if (r != 0) {
  err:
    onig_free(*reg);
    *reg = NULL;
  }
  return r;
}


set_bmh_search_skip_table(UChar* s, UChar* end, OnigEncoding enc ARG_UNUSED,
                          UChar skip[])
{
  int i, len;

  len = (int )(end - s);
  if (len < ONIG_CHAR_TABLE_SIZE) {
    for (i = 0; i < ONIG_CHAR_TABLE_SIZE; i++) skip[i] = len;

    for (i = 0; i < len - 1; i++)
      skip[s[i]] = len - 1 - i;

    return 0;
  }
  else {
    return ONIGERR_PARSER_BUG;
  }
}


alt_merge_opt_exact(OptExact* to, OptExact* add, OptEnv* env)
{
  int i, j, len;

  if (add->len == 0 || to->len == 0) {
    clear_opt_exact(to);
    return ;
  }

  if (! is_equal_mml(&to->mmd, &add->mmd)) {
    clear_opt_exact(to);
    return ;
  }

  for (i = 0; i < to->len && i < add->len; ) {
    if (to->s[i] != add->s[i]) break;
    len = enclen(env->enc, to->s + i);

    for (j = 1; j < len; j++) {
      if (to->s[i+j] != add->s[i+j]) break;
    }
    if (j < len) break;
    i += len;
  }

  if (! add->reach_end || i < add->len || i < to->len) {
    to->reach_end = 0;
  }
  to->len = i;
  to->ignore_case |= add->ignore_case;

  alt_merge_opt_anc_info(&to->anc, &add->anc);
  if (! to->reach_end) to->anc.right = 0;
}


setup_called_state_call(Node* node, int state)
{
  switch (NODE_TYPE(node)) {
  case NODE_ALT:
    state |= IN_ALT;
    /* fall */
  case NODE_LIST:
    do {
      setup_called_state_call(NODE_CAR(node), state);
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_QUANT:
    {
      QuantNode* qn = QUANT_(node);

      if (IS_REPEAT_INFINITE(qn->upper) || qn->upper >= 2)
        state |= IN_REAL_REPEAT;
      if (qn->lower != qn->upper)
        state |= IN_VAR_REPEAT;

      setup_called_state_call(NODE_QUANT_BODY(qn), state);
    }
    break;

  case NODE_ANCHOR:
    {
      AnchorNode* an = ANCHOR_(node);

      switch (an->type) {
      case ANCHOR_PREC_READ_NOT:
      case ANCHOR_LOOK_BEHIND_NOT:
        state |= IN_NOT;
        /* fall */
      case ANCHOR_PREC_READ:
      case ANCHOR_LOOK_BEHIND:
        setup_called_state_call(NODE_ANCHOR_BODY(an), state);
        break;
      default:
        break;
      }
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      if (en->type == ENCLOSURE_MEMORY) {
        if (NODE_IS_MARK1(node)) {
          if ((~en->m.called_state & state) != 0) {
            en->m.called_state |= state;
            setup_called_state_call(NODE_BODY(node), state);
          }
        }
        else {
          NODE_STATUS_ADD(node, MARK1);
          en->m.called_state |= state;
          setup_called_state_call(NODE_BODY(node), state);
          NODE_STATUS_REMOVE(node, MARK1);
        }
      }
      else if (en->type == ENCLOSURE_IF_ELSE) {
        if (IS_NOT_NULL(en->te.Then)) {
          setup_called_state_call(en->te.Then, state);
        }
        if (IS_NOT_NULL(en->te.Else))
          setup_called_state_call(en->te.Else, state);
      }
      else {
        setup_called_state_call(NODE_BODY(node), state);
      }
    }
    break;

  case NODE_CALL:
    setup_called_state_call(NODE_BODY(node), state);
    break;

  default:
    break;
  }
}


compile_string_node(Node* node, regex_t* reg)
{
  int r, len, prev_len, slen, ambig;
  UChar *p, *prev, *end;
  StrNode* sn;
  OnigEncoding enc = reg->enc;

  sn = STR_(node);
  if (sn->end <= sn->s)
    return 0;

  end = sn->end;
  ambig = NODE_STRING_IS_AMBIG(node);

  p = prev = sn->s;
  prev_len = enclen(enc, p);
  p += prev_len;
  slen = 1;

  for (; p < end; ) {
    len = enclen(enc, p);
    if (len == prev_len) {
      slen++;
    }
    else {
      r = add_compile_string(prev, prev_len, slen, reg, ambig);
      if (r != 0) return r;

      prev  = p;
      slen  = 1;
      prev_len = len;
    }

    p += len;
  }

  return add_compile_string(prev, prev_len, slen, reg, ambig);
}


compile_string_raw_node(StrNode* sn, regex_t* reg)
{
  if (sn->end <= sn->s)
    return 0;

  return add_compile_string(sn->s, 1 /* sb */, (int )(sn->end - sn->s), reg, 0);
}


setup_call2_call(Node* node)
{
  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    do {
      setup_call2_call(NODE_CAR(node));
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_QUANT:
    setup_call2_call(NODE_BODY(node));
    break;

  case NODE_ANCHOR:
    if (ANCHOR_HAS_BODY(ANCHOR_(node)))
      setup_call2_call(NODE_BODY(node));
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      if (en->type == ENCLOSURE_MEMORY) {
        if (! NODE_IS_MARK1(node)) {
          NODE_STATUS_ADD(node, MARK1);
          setup_call2_call(NODE_BODY(node));
          NODE_STATUS_REMOVE(node, MARK1);
        }
      }
      else if (en->type == ENCLOSURE_IF_ELSE) {
        setup_call2_call(NODE_BODY(node));
        if (IS_NOT_NULL(en->te.Then))
          setup_call2_call(en->te.Then);
        if (IS_NOT_NULL(en->te.Else))
          setup_call2_call(en->te.Else);
      }
      else {
        setup_call2_call(NODE_BODY(node));
      }
    }
    break;

  case NODE_CALL:
    if (! NODE_IS_MARK1(node)) {
      NODE_STATUS_ADD(node, MARK1);
      {
        CallNode* cn = CALL_(node);
        Node* called = NODE_CALL_BODY(cn);

        cn->entry_count++;

        NODE_STATUS_ADD(called, CALLED);
        ENCLOSURE_(called)->m.entry_count++;
        setup_call2_call(called);
      }
      NODE_STATUS_REMOVE(node, MARK1);
    }
    break;

  default:
    break;
  }
}


comp_opt_exact_or_map(OptExact* e, OptMap* m)
{
#define COMP_EM_BASE  20
  int ae, am;

  if (m->value <= 0) return -1;

  ae = COMP_EM_BASE * e->len * (e->ignore_case ? 1 : 2);
  am = COMP_EM_BASE * 5 * 2 / m->value;
  return comp_distance_value(&e->mmd, &m->mmd, ae, am);
}


setup_called_state(Node* node, int state)
{
  switch (NODE_TYPE(node)) {
  case NODE_ALT:
    state |= IN_ALT;
    /* fall */
  case NODE_LIST:
    do {
      setup_called_state(NODE_CAR(node), state);
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    break;

#ifdef USE_CALL
  case NODE_CALL:
    setup_called_state_call(node, state);
    break;
#endif

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      switch (en->type) {
      case ENCLOSURE_MEMORY:
        if (en->m.entry_count > 1)
          state |= IN_MULTI_ENTRY;

        en->m.called_state |= state;
        /* fall */
      case ENCLOSURE_OPTION:
      case ENCLOSURE_STOP_BACKTRACK:
        setup_called_state(NODE_BODY(node), state);
        break;
      case ENCLOSURE_IF_ELSE:
        setup_called_state(NODE_BODY(node), state);
        if (IS_NOT_NULL(en->te.Then))
          setup_called_state(en->te.Then, state);
        if (IS_NOT_NULL(en->te.Else))
          setup_called_state(en->te.Else, state);
        break;
      }
    }
    break;

  case NODE_QUANT:
    {
      QuantNode* qn = QUANT_(node);

      if (IS_REPEAT_INFINITE(qn->upper) || qn->upper >= 2)
        state |= IN_REAL_REPEAT;
      if (qn->lower != qn->upper)
        state |= IN_VAR_REPEAT;

      setup_called_state(NODE_QUANT_BODY(qn), state);
    }
    break;

  case NODE_ANCHOR:
    {
      AnchorNode* an = ANCHOR_(node);

      switch (an->type) {
      case ANCHOR_PREC_READ_NOT:
      case ANCHOR_LOOK_BEHIND_NOT:
        state |= IN_NOT;
        /* fall */
      case ANCHOR_PREC_READ:
      case ANCHOR_LOOK_BEHIND:
        setup_called_state(NODE_ANCHOR_BODY(an), state);
        break;
      default:
        break;
      }
    }
    break;

  case NODE_BACKREF:
  case NODE_STRING:
  case NODE_CTYPE:
  case NODE_CCLASS:
  case NODE_GIMMICK:
  default:
    break;
  }
}


set_optimize_info_from_tree(Node* node, regex_t* reg, ScanEnv* scan_env)
{
  int r;
  NodeOpt opt;
  OptEnv env;

  env.enc            = reg->enc;
  env.options        = reg->options;
  env.case_fold_flag = reg->case_fold_flag;
  env.scan_env       = scan_env;
  clear_mml(&env.mmd);

  r = optimize_nodes(node, &opt, &env);
  if (r != 0) return r;

  reg->anchor = opt.anc.left & (ANCHOR_BEGIN_BUF |
        ANCHOR_BEGIN_POSITION | ANCHOR_ANYCHAR_INF | ANCHOR_ANYCHAR_INF_ML |
        ANCHOR_LOOK_BEHIND);

  if ((opt.anc.left & (ANCHOR_LOOK_BEHIND | ANCHOR_PREC_READ_NOT)) != 0)
    reg->anchor &= ~ANCHOR_ANYCHAR_INF_ML;

  reg->anchor |= opt.anc.right & (ANCHOR_END_BUF | ANCHOR_SEMI_END_BUF |
       ANCHOR_PREC_READ_NOT);

  if (reg->anchor & (ANCHOR_END_BUF | ANCHOR_SEMI_END_BUF)) {
    reg->anchor_dmin = opt.len.min;
    reg->anchor_dmax = opt.len.max;
  }

  if (opt.exb.len > 0 || opt.exm.len > 0) {
    select_opt_exact(reg->enc, &opt.exb, &opt.exm);
    if (opt.map.value > 0 && comp_opt_exact_or_map(&opt.exb, &opt.map) > 0) {
      goto set_map;
    }
    else {
      r = set_optimize_exact(reg, &opt.exb);
      set_sub_anchor(reg, &opt.exb.anc);
    }
  }
  else if (opt.map.value > 0) {
  set_map:
    set_optimize_map(reg, &opt.map);
    set_sub_anchor(reg, &opt.map.anc);
  }
  else {
    reg->sub_anchor |= opt.anc.left & ANCHOR_BEGIN_LINE;
    if (opt.len.max == 0)
      reg->sub_anchor |= opt.anc.right & ANCHOR_END_LINE;
  }

#if defined(ONIG_DEBUG_COMPILE) || defined(ONIG_DEBUG_MATCH)
  print_optimize_info(stderr, reg);
#endif
  return r;
}


check_type_tree(Node* node, int type_mask, int enclosure_mask, int anchor_mask)
{
  NodeType type;
  int r = 0;

  type = NODE_TYPE(node);
  if ((NODE_TYPE2BIT(type) & type_mask) == 0)
    return 1;

  switch (type) {
  case NODE_LIST:
  case NODE_ALT:
    do {
      r = check_type_tree(NODE_CAR(node), type_mask, enclosure_mask,
                          anchor_mask);
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_QUANT:
    r = check_type_tree(NODE_BODY(node), type_mask, enclosure_mask, anchor_mask);
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);
      if (((1<<en->type) & enclosure_mask) == 0)
        return 1;

      r = check_type_tree(NODE_BODY(node), type_mask, enclosure_mask, anchor_mask);
      if (r == 0 && en->type == ENCLOSURE_IF_ELSE) {
        if (IS_NOT_NULL(en->te.Then)) {
          r = check_type_tree(en->te.Then, type_mask, enclosure_mask, anchor_mask);
          if (r != 0) break;
        }
        if (IS_NOT_NULL(en->te.Else)) {
          r = check_type_tree(en->te.Else, type_mask, enclosure_mask, anchor_mask);
        }
      }
    }
    break;

  case NODE_ANCHOR:
    type = ANCHOR_(node)->type;
    if ((type & anchor_mask) == 0)
      return 1;

    if (IS_NOT_NULL(NODE_BODY(node)))
      r = check_type_tree(NODE_BODY(node), type_mask, enclosure_mask, anchor_mask);
    break;

  case NODE_GIMMICK:
  default:
    break;
  }
  return r;
}


compile_tree(Node* node, regex_t* reg, ScanEnv* env)
{
  int n, len, pos, r = 0;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
    do {
      r = compile_tree(NODE_CAR(node), reg, env);
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_ALT:
    {
      Node* x = node;
      len = 0;
      do {
        len += compile_length_tree(NODE_CAR(x), reg);
        if (IS_NOT_NULL(NODE_CDR(x))) {
          len += SIZE_OP_PUSH + SIZE_OP_JUMP;
        }
      } while (IS_NOT_NULL(x = NODE_CDR(x)));
      pos = reg->used + len;  /* goal position */

      do {
        len = compile_length_tree(NODE_CAR(node), reg);
        if (IS_NOT_NULL(NODE_CDR(node))) {
          enum OpCode push = NODE_IS_SUPER(node) ? OP_PUSH_SUPER : OP_PUSH;
          r = add_opcode_rel_addr(reg, push, len + SIZE_OP_JUMP);
          if (r != 0) break;
        }
        r = compile_tree(NODE_CAR(node), reg, env);
        if (r != 0) break;
        if (IS_NOT_NULL(NODE_CDR(node))) {
          len = pos - (reg->used + SIZE_OP_JUMP);
          r = add_opcode_rel_addr(reg, OP_JUMP, len);
          if (r != 0) break;
        }
      } while (IS_NOT_NULL(node = NODE_CDR(node)));
    }
    break;

  case NODE_STRING:
    if (NODE_STRING_IS_RAW(node))
      r = compile_string_raw_node(STR_(node), reg);
    else
      r = compile_string_node(node, reg);
    break;

  case NODE_CCLASS:
    r = compile_cclass_node(CCLASS_(node), reg);
    break;

  case NODE_CTYPE:
    {
      int op;

      switch (CTYPE_(node)->ctype) {
      case CTYPE_ANYCHAR:
        if (IS_MULTILINE(CTYPE_OPTION(node, reg)))
          r = add_opcode(reg, OP_ANYCHAR_ML);
        else
          r = add_opcode(reg, OP_ANYCHAR);
        break;

      case ONIGENC_CTYPE_WORD:
        if (CTYPE_(node)->ascii_mode == 0) {
          op = CTYPE_(node)->not != 0 ? OP_NO_WORD : OP_WORD;
        }
        else {
          op = CTYPE_(node)->not != 0 ? OP_NO_WORD_ASCII : OP_WORD_ASCII;
        }
        r = add_opcode(reg, op);
        break;

      default:
        return ONIGERR_TYPE_BUG;
        break;
      }
    }
    break;

  case NODE_BACKREF:
    {
      BackRefNode* br = BACKREF_(node);

      if (NODE_IS_CHECKER(node)) {
#ifdef USE_BACKREF_WITH_LEVEL
        if (NODE_IS_NEST_LEVEL(node)) {
          r = add_opcode(reg, OP_BACKREF_CHECK_WITH_LEVEL);
          if (r != 0) return r;
          r = add_length(reg, br->nest_level);
          if (r != 0) return r;
        }
        else
#endif
          {
            r = add_opcode(reg, OP_BACKREF_CHECK);
            if (r != 0) return r;
          }

        goto add_bacref_mems;
      }
      else {
#ifdef USE_BACKREF_WITH_LEVEL
        if (NODE_IS_NEST_LEVEL(node)) {
          r = add_opcode(reg, OP_BACKREF_WITH_LEVEL);
          if (r != 0) return r;
          r = add_option(reg, (reg->options & ONIG_OPTION_IGNORECASE));
          if (r != 0) return r;
          r = add_length(reg, br->nest_level);
          if (r != 0) return r;

          goto add_bacref_mems;
        }
        else
#endif
        if (br->back_num == 1) {
          n = br->back_static[0];
          if (IS_IGNORECASE(reg->options)) {
            r = add_opcode(reg, OP_BACKREF_N_IC);
            if (r != 0) return r;
            r = add_mem_num(reg, n);
          }
          else {
            switch (n) {
            case 1:  r = add_opcode(reg, OP_BACKREF1); break;
            case 2:  r = add_opcode(reg, OP_BACKREF2); break;
            default:
              r = add_opcode(reg, OP_BACKREF_N);
              if (r != 0) return r;
              r = add_mem_num(reg, n);
              break;
            }
          }
        }
        else {
          int i;
          int* p;

          if (IS_IGNORECASE(reg->options)) {
            r = add_opcode(reg, OP_BACKREF_MULTI_IC);
          }
          else {
            r = add_opcode(reg, OP_BACKREF_MULTI);
          }
          if (r != 0) return r;

        add_bacref_mems:
          r = add_length(reg, br->back_num);
          if (r != 0) return r;
          p = BACKREFS_P(br);
          for (i = br->back_num - 1; i >= 0; i--) {
            r = add_mem_num(reg, p[i]);
            if (r != 0) return r;
          }
        }
      }
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    r = compile_call(CALL_(node), reg, env);
    break;
#endif

  case NODE_QUANT:
    r = compile_quantifier_node(QUANT_(node), reg, env);
    break;

  case NODE_ENCLOSURE:
    r = compile_enclosure_node(ENCLOSURE_(node), reg, env);
    break;

  case NODE_ANCHOR:
    r = compile_anchor_node(ANCHOR_(node), reg, env);
    break;

  case NODE_GIMMICK:
    r = compile_gimmick_node(GIMMICK_(node), reg);
    break;

  default:
#ifdef ONIG_DEBUG
    fprintf(stderr, "compile_tree: undefined node type %d\n", NODE_TYPE(node));
#endif
    break;
  }

  return r;
}


add_mml(MinMax* to, MinMax* from)
{
  to->min = distance_add(to->min, from->min);
  to->max = distance_add(to->max, from->max);
}


numbered_ref_check(Node* node)
{
  int r = 0;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    do {
      r = numbered_ref_check(NODE_CAR(node));
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_ANCHOR:
    if (IS_NULL(NODE_BODY(node)))
      break;
    /* fall */
  case NODE_QUANT:
    r = numbered_ref_check(NODE_BODY(node));
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      r = numbered_ref_check(NODE_BODY(node));
      if (r != 0) return r;

      if (en->type == ENCLOSURE_IF_ELSE) {
        if (IS_NOT_NULL(en->te.Then)) {
          r = numbered_ref_check(en->te.Then);
          if (r != 0) return r;
        }
        if (IS_NOT_NULL(en->te.Else)) {
          r = numbered_ref_check(en->te.Else);
          if (r != 0) return r;
        }
      }
    }

    break;

  case NODE_BACKREF:
    if (! NODE_IS_BY_NAME(node))
      return ONIGERR_NUMBERED_BACKREF_OR_CALL_NOT_ALLOWED;
    break;

  default:
    break;
  }

  return r;
}


add_abs_addr(regex_t* reg, int addr)
{
  AbsAddrType ra = (AbsAddrType )addr;

  BB_ADD(reg, &ra, SIZE_ABSADDR);
  return 0;
}


is_exclusive(Node* x, Node* y, regex_t* reg)
{
  int i, len;
  OnigCodePoint code;
  UChar *p;
  NodeType ytype;

 retry:
  ytype = NODE_TYPE(y);
  switch (NODE_TYPE(x)) {
  case NODE_CTYPE:
    {
      if (CTYPE_(x)->ctype == CTYPE_ANYCHAR ||
          CTYPE_(y)->ctype == CTYPE_ANYCHAR)
        break;

      switch (ytype) {
      case NODE_CTYPE:
        if (CTYPE_(y)->ctype == CTYPE_(x)->ctype &&
            CTYPE_(y)->not   != CTYPE_(x)->not &&
            CTYPE_(y)->ascii_mode == CTYPE_(x)->ascii_mode)
          return 1;
        else
          return 0;
        break;

      case NODE_CCLASS:
      swap:
        {
          Node* tmp;
          tmp = x; x = y; y = tmp;
          goto retry;
        }
        break;

      case NODE_STRING:
        goto swap;
        break;

      default:
        break;
      }
    }
    break;

  case NODE_CCLASS:
    {
      int range;
      CClassNode* xc = CCLASS_(x);

      switch (ytype) {
      case NODE_CTYPE:
        switch (CTYPE_(y)->ctype) {
        case CTYPE_ANYCHAR:
          return 0;
          break;

        case ONIGENC_CTYPE_WORD:
          if (CTYPE_(y)->not == 0) {
            if (IS_NULL(xc->mbuf) && !IS_NCCLASS_NOT(xc)) {
              range = CTYPE_(y)->ascii_mode != 0 ? 128 : SINGLE_BYTE_SIZE;
              for (i = 0; i < range; i++) {
                if (BITSET_AT(xc->bs, i)) {
                  if (ONIGENC_IS_CODE_WORD(reg->enc, i)) return 0;
                }
              }
              return 1;
            }
            return 0;
          }
          else {
            if (IS_NOT_NULL(xc->mbuf)) return 0;
            if (IS_NCCLASS_NOT(xc)) return 0;

            range = CTYPE_(y)->ascii_mode != 0 ? 128 : SINGLE_BYTE_SIZE;
            for (i = 0; i < range; i++) {
              if (! ONIGENC_IS_CODE_WORD(reg->enc, i)) {
                if (BITSET_AT(xc->bs, i))
                  return 0;
              }
            }
            for (i = range; i < SINGLE_BYTE_SIZE; i++) {
              if (BITSET_AT(xc->bs, i)) return 0;
            }
            return 1;
          }
          break;

        default:
          break;
        }
        break;

      case NODE_CCLASS:
        {
          int v;
          CClassNode* yc = CCLASS_(y);

          for (i = 0; i < SINGLE_BYTE_SIZE; i++) {
            v = BITSET_AT(xc->bs, i);
            if ((v != 0 && !IS_NCCLASS_NOT(xc)) || (v == 0 && IS_NCCLASS_NOT(xc))) {
              v = BITSET_AT(yc->bs, i);
              if ((v != 0 && !IS_NCCLASS_NOT(yc)) ||
                  (v == 0 && IS_NCCLASS_NOT(yc)))
                return 0;
            }
          }
          if ((IS_NULL(xc->mbuf) && !IS_NCCLASS_NOT(xc)) ||
              (IS_NULL(yc->mbuf) && !IS_NCCLASS_NOT(yc)))
            return 1;
          return 0;
        }
        break;

      case NODE_STRING:
        goto swap;
        break;

      default:
        break;
      }
    }
    break;

  case NODE_STRING:
    {
      StrNode* xs = STR_(x);

      if (NODE_STRING_LEN(x) == 0)
        break;

      switch (ytype) {
      case NODE_CTYPE:
        switch (CTYPE_(y)->ctype) {
        case CTYPE_ANYCHAR:
          break;

        case ONIGENC_CTYPE_WORD:
          if (CTYPE_(y)->ascii_mode == 0) {
            if (ONIGENC_IS_MBC_WORD(reg->enc, xs->s, xs->end))
              return CTYPE_(y)->not;
            else
              return !(CTYPE_(y)->not);
          }
          else {
            if (ONIGENC_IS_MBC_WORD_ASCII(reg->enc, xs->s, xs->end))
              return CTYPE_(y)->not;
            else
              return !(CTYPE_(y)->not);
          }
          break;
        default:
          break;
        }
        break;

      case NODE_CCLASS:
        {
          CClassNode* cc = CCLASS_(y);

          code = ONIGENC_MBC_TO_CODE(reg->enc, xs->s,
                                     xs->s + ONIGENC_MBC_MAXLEN(reg->enc));
          return onig_is_code_in_cc(reg->enc, code, cc) == 0;
        }
        break;

      case NODE_STRING:
        {
          UChar *q;
          StrNode* ys = STR_(y);

          len = NODE_STRING_LEN(x);
          if (len > NODE_STRING_LEN(y)) len = NODE_STRING_LEN(y);
          if (NODE_STRING_IS_AMBIG(x) || NODE_STRING_IS_AMBIG(y)) {
            /* tiny version */
            return 0;
          }
          else {
            for (i = 0, p = ys->s, q = xs->s; i < len; i++, p++, q++) {
              if (*p != *q) return 1;
            }
          }
        }
        break;

      default:
        break;
      }
    }
    break;

  default:
    break;
  }

  return 0;
}


compile_length_gimmick_node(GimmickNode* node, regex_t* reg)
{
  int len;

  switch (node->type) {
  case GIMMICK_FAIL:
    len = SIZE_OP_FAIL;
    break;

  case GIMMICK_KEEP:
  case GIMMICK_SAVE:
    len = SIZE_OP_PUSH_SAVE_VAL;
    break;

  case GIMMICK_UPDATE_VAR:
    len = SIZE_OP_UPDATE_VAR;
    break;

#ifdef USE_CALLOUT
  case GIMMICK_CALLOUT:
    switch (node->detail_type) {
    case ONIG_CALLOUT_OF_CONTENTS:
      len = SIZE_OP_CALLOUT_CONTENTS;
      break;
    case ONIG_CALLOUT_OF_NAME:
      len = SIZE_OP_CALLOUT_NAME;
      break;

    default:
      len = ONIGERR_TYPE_BUG;
      break;
    }
    break;
#endif
  }

  return len;
}


renumber_by_map(Node* node, GroupNumRemap* map)
{
  int r = 0;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    do {
      r = renumber_by_map(NODE_CAR(node), map);
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_QUANT:
    r = renumber_by_map(NODE_BODY(node), map);
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      r = renumber_by_map(NODE_BODY(node), map);
      if (r != 0) return r;

      if (en->type == ENCLOSURE_IF_ELSE) {
        if (IS_NOT_NULL(en->te.Then)) {
          r = renumber_by_map(en->te.Then, map);
          if (r != 0) return r;
        }
        if (IS_NOT_NULL(en->te.Else)) {
          r = renumber_by_map(en->te.Else, map);
          if (r != 0) return r;
        }
      }
    }
    break;

  case NODE_BACKREF:
    r = renumber_node_backref(node, map);
    break;

  case NODE_ANCHOR:
    if (IS_NOT_NULL(NODE_BODY(node)))
      r = renumber_by_map(NODE_BODY(node), map);
    break;

  default:
    break;
  }

  return r;
}


quantifiers_memory_node_info(Node* node)
{
  int r = QUANT_BODY_IS_EMPTY;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    {
      int v;
      do {
        v = quantifiers_memory_node_info(NODE_CAR(node));
        if (v > r) r = v;
      } while (IS_NOT_NULL(node = NODE_CDR(node)));
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    if (NODE_IS_RECURSION(node)) {
      return QUANT_BODY_IS_EMPTY_REC; /* tiny version */
    }
    else
      r = quantifiers_memory_node_info(NODE_BODY(node));
    break;
#endif

  case NODE_QUANT:
    {
      QuantNode* qn = QUANT_(node);
      if (qn->upper != 0) {
        r = quantifiers_memory_node_info(NODE_BODY(node));
      }
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);
      switch (en->type) {
      case ENCLOSURE_MEMORY:
        if (NODE_IS_RECURSION(node)) {
          return QUANT_BODY_IS_EMPTY_REC;
        }
        return QUANT_BODY_IS_EMPTY_MEM;
        break;

      case ENCLOSURE_OPTION:
      case ENCLOSURE_STOP_BACKTRACK:
        r = quantifiers_memory_node_info(NODE_BODY(node));
        break;
      case ENCLOSURE_IF_ELSE:
        {
          int v;
          r = quantifiers_memory_node_info(NODE_BODY(node));
          if (IS_NOT_NULL(en->te.Then)) {
            v = quantifiers_memory_node_info(en->te.Then);
            if (v > r) r = v;
          }
          if (IS_NOT_NULL(en->te.Else)) {
            v = quantifiers_memory_node_info(en->te.Else);
            if (v > r) r = v;
          }
        }
        break;
      default:
        break;
      }
    }
    break;

  case NODE_BACKREF:
  case NODE_STRING:
  case NODE_CTYPE:
  case NODE_CCLASS:
  case NODE_ANCHOR:
  case NODE_GIMMICK:
  default:
    break;
  }

  return r;
}


disable_noname_group_capture(Node** root, regex_t* reg, ScanEnv* env)
{
  int r, i, pos, counter;
  MemStatusType loc;
  GroupNumRemap* map;

  map = (GroupNumRemap* )xalloca(sizeof(GroupNumRemap) * (env->num_mem + 1));
  CHECK_NULL_RETURN_MEMERR(map);
  for (i = 1; i <= env->num_mem; i++) {
    map[i].new_val = 0;
  }
  counter = 0;
  r = noname_disable_map(root, map, &counter);
  if (r != 0) return r;

  r = renumber_by_map(*root, map);
  if (r != 0) return r;

  for (i = 1, pos = 1; i <= env->num_mem; i++) {
    if (map[i].new_val > 0) {
      SCANENV_MEMENV(env)[pos] = SCANENV_MEMENV(env)[i];
      pos++;
    }
  }

  loc = env->capture_history;
  MEM_STATUS_CLEAR(env->capture_history);
  for (i = 1; i <= ONIG_MAX_CAPTURE_HISTORY_GROUP; i++) {
    if (MEM_STATUS_AT(loc, i)) {
      MEM_STATUS_ON_SIMPLE(env->capture_history, map[i].new_val);
    }
  }

  env->num_mem = env->num_named;
  reg->num_mem = env->num_named;

  return onig_renumber_name_table(reg, map);
}


optimize_nodes(Node* node, NodeOpt* opt, OptEnv* env)
{
  int i;
  int r;
  NodeOpt xo;
  OnigEncoding enc;

  r = 0;
  enc = env->enc;
  clear_node_opt_info(opt);
  set_bound_node_opt_info(opt, &env->mmd);

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
    {
      OptEnv nenv;
      Node* nd = node;

      copy_opt_env(&nenv, env);
      do {
        r = optimize_nodes(NODE_CAR(nd), &xo, &nenv);
        if (r == 0) {
          add_mml(&nenv.mmd, &xo.len);
          concat_left_node_opt_info(enc, opt, &xo);
        }
      } while (r == 0 && IS_NOT_NULL(nd = NODE_CDR(nd)));
    }
    break;

  case NODE_ALT:
    {
      Node* nd = node;

      do {
        r = optimize_nodes(NODE_CAR(nd), &xo, env);
        if (r == 0) {
          if (nd == node) copy_node_opt_info(opt, &xo);
          else            alt_merge_node_opt_info(opt, &xo, env);
        }
      } while ((r == 0) && IS_NOT_NULL(nd = NODE_CDR(nd)));
    }
    break;

  case NODE_STRING:
    {
      StrNode* sn = STR_(node);
      int slen = (int )(sn->end - sn->s);
      /* int is_raw = NODE_STRING_IS_RAW(node); */

      if (! NODE_STRING_IS_AMBIG(node)) {
        concat_opt_exact_str(&opt->exb, sn->s, sn->end, enc);
        if (slen > 0) {
          add_char_opt_map(&opt->map, *(sn->s), enc);
        }
        set_mml(&opt->len, slen, slen);
      }
      else {
        int max;

        if (NODE_STRING_IS_DONT_GET_OPT_INFO(node)) {
          int n = onigenc_strlen(enc, sn->s, sn->end);
          max = ONIGENC_MBC_MAXLEN_DIST(enc) * n;
        }
        else {
          concat_opt_exact_str(&opt->exb, sn->s, sn->end, enc);
          opt->exb.ignore_case = 1;

          if (slen > 0) {
            r = add_char_amb_opt_map(&opt->map, sn->s, sn->end,
                                     enc, env->case_fold_flag);
            if (r != 0) break;
          }

          max = slen;
        }

        set_mml(&opt->len, slen, max);
      }

      if (opt->exb.len == slen)
        opt->exb.reach_end = 1;
    }
    break;

  case NODE_CCLASS:
    {
      int z;
      CClassNode* cc = CCLASS_(node);

      /* no need to check ignore case. (set in setup_tree()) */

      if (IS_NOT_NULL(cc->mbuf) || IS_NCCLASS_NOT(cc)) {
        OnigLen min = ONIGENC_MBC_MINLEN(enc);
        OnigLen max = ONIGENC_MBC_MAXLEN_DIST(enc);

        set_mml(&opt->len, min, max);
      }
      else {
        for (i = 0; i < SINGLE_BYTE_SIZE; i++) {
          z = BITSET_AT(cc->bs, i);
          if ((z && ! IS_NCCLASS_NOT(cc)) || (! z && IS_NCCLASS_NOT(cc))) {
            add_char_opt_map(&opt->map, (UChar )i, enc);
          }
        }
        set_mml(&opt->len, 1, 1);
      }
    }
    break;

  case NODE_CTYPE:
    {
      int min, max;
      int range;

      max = ONIGENC_MBC_MAXLEN_DIST(enc);

      if (max == 1) {
        min = 1;

        switch (CTYPE_(node)->ctype) {
        case CTYPE_ANYCHAR:
          break;

        case ONIGENC_CTYPE_WORD:
          range = CTYPE_(node)->ascii_mode != 0 ? 128 : SINGLE_BYTE_SIZE;
          if (CTYPE_(node)->not != 0) {
            for (i = 0; i < range; i++) {
              if (! ONIGENC_IS_CODE_WORD(enc, i)) {
                add_char_opt_map(&opt->map, (UChar )i, enc);
              }
            }
            for (i = range; i < SINGLE_BYTE_SIZE; i++) {
              add_char_opt_map(&opt->map, (UChar )i, enc);
            }
          }
          else {
            for (i = 0; i < range; i++) {
              if (ONIGENC_IS_CODE_WORD(enc, i)) {
                add_char_opt_map(&opt->map, (UChar )i, enc);
              }
            }
          }
          break;
        }
      }
      else {
        min = ONIGENC_MBC_MINLEN(enc);
      }
      set_mml(&opt->len, min, max);
    }
    break;

  case NODE_ANCHOR:
    switch (ANCHOR_(node)->type) {
    case ANCHOR_BEGIN_BUF:
    case ANCHOR_BEGIN_POSITION:
    case ANCHOR_BEGIN_LINE:
    case ANCHOR_END_BUF:
    case ANCHOR_SEMI_END_BUF:
    case ANCHOR_END_LINE:
    case ANCHOR_PREC_READ_NOT:
    case ANCHOR_LOOK_BEHIND:
      add_opt_anc_info(&opt->anc, ANCHOR_(node)->type);
      break;

    case ANCHOR_PREC_READ:
      {
        r = optimize_nodes(NODE_BODY(node), &xo, env);
        if (r == 0) {
          if (xo.exb.len > 0)
            copy_opt_exact(&opt->expr, &xo.exb);
          else if (xo.exm.len > 0)
            copy_opt_exact(&opt->expr, &xo.exm);

          opt->expr.reach_end = 0;

          if (xo.map.value > 0)
            copy_opt_map(&opt->map, &xo.map);
        }
      }
      break;

    case ANCHOR_LOOK_BEHIND_NOT:
      break;
    }
    break;

  case NODE_BACKREF:
    if (! NODE_IS_CHECKER(node)) {
      int* backs;
      OnigLen min, max, tmin, tmax;
      MemEnv* mem_env = SCANENV_MEMENV(env->scan_env);
      BackRefNode* br = BACKREF_(node);

      if (NODE_IS_RECURSION(node)) {
        set_mml(&opt->len, 0, INFINITE_LEN);
        break;
      }
      backs = BACKREFS_P(br);
      min = tree_min_len(mem_env[backs[0]].node, env->scan_env);
      max = tree_max_len(mem_env[backs[0]].node, env->scan_env);
      for (i = 1; i < br->back_num; i++) {
        tmin = tree_min_len(mem_env[backs[i]].node, env->scan_env);
        tmax = tree_max_len(mem_env[backs[i]].node, env->scan_env);
        if (min > tmin) min = tmin;
        if (max < tmax) max = tmax;
      }
      set_mml(&opt->len, min, max);
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    if (NODE_IS_RECURSION(node))
      set_mml(&opt->len, 0, INFINITE_LEN);
    else {
      OnigOptionType save = env->options;
      env->options = ENCLOSURE_(NODE_BODY(node))->o.options;
      r = optimize_nodes(NODE_BODY(node), opt, env);
      env->options = save;
    }
    break;
#endif

  case NODE_QUANT:
    {
      OnigLen min, max;
      QuantNode* qn = QUANT_(node);

      r = optimize_nodes(NODE_BODY(node), &xo, env);
      if (r != 0) break;

      if (qn->lower > 0) {
        copy_node_opt_info(opt, &xo);
        if (xo.exb.len > 0) {
          if (xo.exb.reach_end) {
            for (i = 2; i <= qn->lower && ! is_full_opt_exact(&opt->exb); i++) {
              int rc = concat_opt_exact(&opt->exb, &xo.exb, enc);
              if (rc > 0) break;
            }
            if (i < qn->lower) opt->exb.reach_end = 0;
          }
        }

        if (qn->lower != qn->upper) {
          opt->exb.reach_end = 0;
          opt->exm.reach_end = 0;
        }
        if (qn->lower > 1)
          opt->exm.reach_end = 0;
      }

      if (IS_REPEAT_INFINITE(qn->upper)) {
        if (env->mmd.max == 0 &&
            NODE_IS_ANYCHAR(NODE_BODY(node)) && qn->greedy != 0) {
          if (IS_MULTILINE(CTYPE_OPTION(NODE_QUANT_BODY(qn), env)))
            add_opt_anc_info(&opt->anc, ANCHOR_ANYCHAR_INF_ML);
          else
            add_opt_anc_info(&opt->anc, ANCHOR_ANYCHAR_INF);
        }

        max = (xo.len.max > 0 ? INFINITE_LEN : 0);
      }
      else {
        max = distance_multiply(xo.len.max, qn->upper);
      }

      min = distance_multiply(xo.len.min, qn->lower);
      set_mml(&opt->len, min, max);
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      switch (en->type) {
      case ENCLOSURE_OPTION:
        {
          OnigOptionType save = env->options;

          env->options = en->o.options;
          r = optimize_nodes(NODE_BODY(node), opt, env);
          env->options = save;
        }
        break;

      case ENCLOSURE_MEMORY:
#ifdef USE_CALL
        en->opt_count++;
        if (en->opt_count > MAX_NODE_OPT_INFO_REF_COUNT) {
          OnigLen min, max;

          min = 0;
          max = INFINITE_LEN;
          if (NODE_IS_MIN_FIXED(node)) min = en->min_len;
          if (NODE_IS_MAX_FIXED(node)) max = en->max_len;
          set_mml(&opt->len, min, max);
        }
        else
#endif
          {
            r = optimize_nodes(NODE_BODY(node), opt, env);
            if (is_set_opt_anc_info(&opt->anc, ANCHOR_ANYCHAR_INF_MASK)) {
              if (MEM_STATUS_AT0(env->scan_env->backrefed_mem, en->m.regnum))
                remove_opt_anc_info(&opt->anc, ANCHOR_ANYCHAR_INF_MASK);
            }
          }
        break;

      case ENCLOSURE_STOP_BACKTRACK:
        r = optimize_nodes(NODE_BODY(node), opt, env);
        break;

      case ENCLOSURE_IF_ELSE:
        {
          OptEnv nenv;

          copy_opt_env(&nenv, env);
          r = optimize_nodes(NODE_ENCLOSURE_BODY(en), &xo, &nenv);
          if (r == 0) {
            add_mml(&nenv.mmd, &xo.len);
            concat_left_node_opt_info(enc, opt, &xo);
            if (IS_NOT_NULL(en->te.Then)) {
              r = optimize_nodes(en->te.Then, &xo, &nenv);
              if (r == 0) {
                concat_left_node_opt_info(enc, opt, &xo);
              }
            }

            if (IS_NOT_NULL(en->te.Else)) {
              r = optimize_nodes(en->te.Else, &xo, env);
              if (r == 0)
                alt_merge_node_opt_info(opt, &xo, env);
            }
          }
        }
        break;
      }
    }
    break;

  case NODE_GIMMICK:
    break;

  default:
#ifdef ONIG_DEBUG
    fprintf(stderr, "optimize_nodes: undefined node type %d\n", NODE_TYPE(node));
#endif
    r = ONIGERR_TYPE_BUG;
    break;
  }

  return r;
}


compile_call(CallNode* node, regex_t* reg, ScanEnv* env)
{
  int r;

  r = add_opcode(reg, OP_CALL);
  if (r != 0) return r;
  r = unset_addr_list_add(env->unset_addr_list, BB_GET_OFFSET_POS(reg),
                          NODE_CALL_BODY(node));
  if (r != 0) return r;
  r = add_abs_addr(reg, 0 /*dummy addr.*/);
  return r;
}


setup_anchor(Node* node, regex_t* reg, int state, ScanEnv* env)
{
/* allowed node types in look-behind */
#define ALLOWED_TYPE_IN_LB \
  ( NODE_BIT_LIST | NODE_BIT_ALT | NODE_BIT_STRING | NODE_BIT_CCLASS \
  | NODE_BIT_CTYPE | NODE_BIT_ANCHOR | NODE_BIT_ENCLOSURE | NODE_BIT_QUANT \
  | NODE_BIT_CALL | NODE_BIT_GIMMICK)

#define ALLOWED_ENCLOSURE_IN_LB       ( 1<<ENCLOSURE_MEMORY | 1<<ENCLOSURE_OPTION )
#define ALLOWED_ENCLOSURE_IN_LB_NOT   (1<<ENCLOSURE_OPTION)

#define ALLOWED_ANCHOR_IN_LB \
  ( ANCHOR_LOOK_BEHIND | ANCHOR_BEGIN_LINE | ANCHOR_END_LINE | ANCHOR_BEGIN_BUF \
  | ANCHOR_BEGIN_POSITION | ANCHOR_WORD_BOUNDARY | ANCHOR_NO_WORD_BOUNDARY \
  | ANCHOR_WORD_BEGIN | ANCHOR_WORD_END \
  | ANCHOR_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY \
  | ANCHOR_NO_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY )

#define ALLOWED_ANCHOR_IN_LB_NOT \
  ( ANCHOR_LOOK_BEHIND | ANCHOR_LOOK_BEHIND_NOT | ANCHOR_BEGIN_LINE \
  | ANCHOR_END_LINE | ANCHOR_BEGIN_BUF | ANCHOR_BEGIN_POSITION | ANCHOR_WORD_BOUNDARY \
  | ANCHOR_NO_WORD_BOUNDARY | ANCHOR_WORD_BEGIN | ANCHOR_WORD_END \
  | ANCHOR_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY \
  | ANCHOR_NO_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY )

  int r;
  AnchorNode* an = ANCHOR_(node);

  switch (an->type) {
  case ANCHOR_PREC_READ:
    r = setup_tree(NODE_ANCHOR_BODY(an), reg, state, env);
    break;
  case ANCHOR_PREC_READ_NOT:
    r = setup_tree(NODE_ANCHOR_BODY(an), reg, (state | IN_NOT), env);
    break;

  case ANCHOR_LOOK_BEHIND:
    {
      r = check_type_tree(NODE_ANCHOR_BODY(an), ALLOWED_TYPE_IN_LB,
                          ALLOWED_ENCLOSURE_IN_LB, ALLOWED_ANCHOR_IN_LB);
      if (r < 0) return r;
      if (r > 0) return ONIGERR_INVALID_LOOK_BEHIND_PATTERN;
      r = setup_tree(NODE_ANCHOR_BODY(an), reg, state, env);
      if (r != 0) return r;
      r = setup_look_behind(node, reg, env);
    }
    break;

  case ANCHOR_LOOK_BEHIND_NOT:
    {
      r = check_type_tree(NODE_ANCHOR_BODY(an), ALLOWED_TYPE_IN_LB,
                          ALLOWED_ENCLOSURE_IN_LB_NOT, ALLOWED_ANCHOR_IN_LB_NOT);
      if (r < 0) return r;
      if (r > 0) return ONIGERR_INVALID_LOOK_BEHIND_PATTERN;
      r = setup_tree(NODE_ANCHOR_BODY(an), reg, (state | IN_NOT), env);
      if (r != 0) return r;
      r = setup_look_behind(node, reg, env);
    }
    break;

  default:
    r = 0;
    break;
  }

  return r;
}


recursive_call_check_trav(Node* node, ScanEnv* env, int state)
{
  int r = 0;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    {
      int ret;
      do {
        ret = recursive_call_check_trav(NODE_CAR(node), env, state);
        if (ret == FOUND_CALLED_NODE) r = FOUND_CALLED_NODE;
        else if (ret < 0) return ret;
      } while (IS_NOT_NULL(node = NODE_CDR(node)));
    }
    break;

  case NODE_QUANT:
    r = recursive_call_check_trav(NODE_BODY(node), env, state);
    if (QUANT_(node)->upper == 0) {
      if (r == FOUND_CALLED_NODE)
        QUANT_(node)->is_refered = 1;
    }
    break;

  case NODE_ANCHOR:
    {
      AnchorNode* an = ANCHOR_(node);
      if (ANCHOR_HAS_BODY(an))
        r = recursive_call_check_trav(NODE_ANCHOR_BODY(an), env, state);
    }
    break;

  case NODE_ENCLOSURE:
    {
      int ret;
      int state1;
      EnclosureNode* en = ENCLOSURE_(node);

      if (en->type == ENCLOSURE_MEMORY) {
        if (NODE_IS_CALLED(node) || (state & IN_RECURSION) != 0) {
          if (! NODE_IS_RECURSION(node)) {
            NODE_STATUS_ADD(node, MARK1);
            r = recursive_call_check(NODE_BODY(node));
            if (r != 0)
              NODE_STATUS_ADD(node, RECURSION);
            NODE_STATUS_REMOVE(node, MARK1);
          }

          if (NODE_IS_CALLED(node))
            r = FOUND_CALLED_NODE;
        }
      }

      state1 = state;
      if (NODE_IS_RECURSION(node))
        state1 |= IN_RECURSION;

      ret = recursive_call_check_trav(NODE_BODY(node), env, state1);
      if (ret == FOUND_CALLED_NODE)
        r = FOUND_CALLED_NODE;

      if (en->type == ENCLOSURE_IF_ELSE) {
        if (IS_NOT_NULL(en->te.Then)) {
          ret = recursive_call_check_trav(en->te.Then, env, state1);
          if (ret == FOUND_CALLED_NODE)
            r = FOUND_CALLED_NODE;
        }
        if (IS_NOT_NULL(en->te.Else)) {
          ret = recursive_call_check_trav(en->te.Else, env, state1);
          if (ret == FOUND_CALLED_NODE)
            r = FOUND_CALLED_NODE;
        }
      }
    }
    break;

  default:
    break;
  }

  return r;
}


compile_length_tree(Node* node, regex_t* reg)
{
  int len, r;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
    len = 0;
    do {
      r = compile_length_tree(NODE_CAR(node), reg);
      if (r < 0) return r;
      len += r;
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    r = len;
    break;

  case NODE_ALT:
    {
      int n;

      n = r = 0;
      do {
        r += compile_length_tree(NODE_CAR(node), reg);
        n++;
      } while (IS_NOT_NULL(node = NODE_CDR(node)));
      r += (SIZE_OP_PUSH + SIZE_OP_JUMP) * (n - 1);
    }
    break;

  case NODE_STRING:
    if (NODE_STRING_IS_RAW(node))
      r = compile_length_string_raw_node(STR_(node), reg);
    else
      r = compile_length_string_node(node, reg);
    break;

  case NODE_CCLASS:
    r = compile_length_cclass_node(CCLASS_(node), reg);
    break;

  case NODE_CTYPE:
    r = SIZE_OPCODE;
    break;

  case NODE_BACKREF:
    {
      BackRefNode* br = BACKREF_(node);

      if (NODE_IS_CHECKER(node)) {
#ifdef USE_BACKREF_WITH_LEVEL
        if (NODE_IS_NEST_LEVEL(node)) {
          r = SIZE_OPCODE + SIZE_LENGTH + SIZE_LENGTH + (SIZE_MEMNUM * br->back_num);
        }
        else
#endif
          r = SIZE_OPCODE + SIZE_LENGTH + (SIZE_MEMNUM * br->back_num);
      }
      else {
#ifdef USE_BACKREF_WITH_LEVEL
        if (NODE_IS_NEST_LEVEL(node)) {
          r = SIZE_OPCODE + SIZE_OPTION + SIZE_LENGTH +
            SIZE_LENGTH + (SIZE_MEMNUM * br->back_num);
        }
        else
#endif
        if (br->back_num == 1) {
          r = ((!IS_IGNORECASE(reg->options) && br->back_static[0] <= 2)
               ? SIZE_OPCODE : (SIZE_OPCODE + SIZE_MEMNUM));
        }
        else {
          r = SIZE_OPCODE + SIZE_LENGTH + (SIZE_MEMNUM * br->back_num);
        }
      }
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    r = SIZE_OP_CALL;
    break;
#endif

  case NODE_QUANT:
    r = compile_length_quantifier_node(QUANT_(node), reg);
    break;

  case NODE_ENCLOSURE:
    r = compile_length_enclosure_node(ENCLOSURE_(node), reg);
    break;

  case NODE_ANCHOR:
    r = compile_length_anchor_node(ANCHOR_(node), reg);
    break;

  case NODE_GIMMICK:
    r = compile_length_gimmick_node(GIMMICK_(node), reg);
    break;

  default:
    return ONIGERR_TYPE_BUG;
    break;
  }

  return r;
}


clear_opt_exact(OptExact* e)
{
  clear_mml(&e->mmd);
  clear_opt_anc_info(&e->anc);
  e->reach_end   = 0;
  e->ignore_case = 0;
  e->len         = 0;
  e->s[0]        = '\0';
}


swap_node(Node* a, Node* b)
{
  Node c;

  c = *a; *a = *b; *b = c;

  if (NODE_TYPE(a) == NODE_STRING) {
    StrNode* sn = STR_(a);
    if (sn->capa == 0) {
      int len = (int )(sn->end - sn->s);
      sn->s   = sn->buf;
      sn->end = sn->s + len;
    }
  }

  if (NODE_TYPE(b) == NODE_STRING) {
    StrNode* sn = STR_(b);
    if (sn->capa == 0) {
      int len = (int )(sn->end - sn->s);
      sn->s   = sn->buf;
      sn->end = sn->s + len;
    }
  }
}


print_indent_tree(FILE* f, Node* node, int indent)
{
  int i;
  NodeType type;
  UChar* p;
  int add = 3;

  Indent(f, indent);
  if (IS_NULL(node)) {
    fprintf(f, "ERROR: null node!!!\n");
    exit (0);
  }

  type = NODE_TYPE(node);
  switch (type) {
  case NODE_LIST:
  case NODE_ALT:
    if (type == NODE_LIST)
      fprintf(f, "<list:%p>\n", node);
    else
      fprintf(f, "<alt:%p>\n", node);

    print_indent_tree(f, NODE_CAR(node), indent + add);
    while (IS_NOT_NULL(node = NODE_CDR(node))) {
      if (NODE_TYPE(node) != type) {
        fprintf(f, "ERROR: list/alt right is not a cons. %d\n", NODE_TYPE(node));
        exit(0);
      }
      print_indent_tree(f, NODE_CAR(node), indent + add);
    }
    break;

  case NODE_STRING:
    fprintf(f, "<string%s:%p>", (NODE_STRING_IS_RAW(node) ? "-raw" : ""), node);
    for (p = STR_(node)->s; p < STR_(node)->end; p++) {
      if (*p >= 0x20 && *p < 0x7f)
        fputc(*p, f);
      else {
        fprintf(f, " 0x%02x", *p);
      }
    }
    break;

  case NODE_CCLASS:
    fprintf(f, "<cclass:%p>", node);
    if (IS_NCCLASS_NOT(CCLASS_(node))) fputs(" not", f);
    if (CCLASS_(node)->mbuf) {
      BBuf* bbuf = CCLASS_(node)->mbuf;
      for (i = 0; i < bbuf->used; i++) {
        if (i > 0) fprintf(f, ",");
        fprintf(f, "%0x", bbuf->p[i]);
      }
    }
    break;

  case NODE_CTYPE:
    fprintf(f, "<ctype:%p> ", node);
    switch (CTYPE_(node)->ctype) {
    case CTYPE_ANYCHAR:
      fprintf(f, "<anychar:%p>", node);
      break;

    case ONIGENC_CTYPE_WORD:
      if (CTYPE_(node)->not != 0)
        fputs("not word", f);
      else
        fputs("word",     f);

      if (CTYPE_(node)->ascii_mode != 0)
        fputs(" (ascii)", f);

      break;

    default:
      fprintf(f, "ERROR: undefined ctype.\n");
      exit(0);
    }
    break;

  case NODE_ANCHOR:
    fprintf(f, "<anchor:%p> ", node);
    switch (ANCHOR_(node)->type) {
    case ANCHOR_BEGIN_BUF:        fputs("begin buf",      f); break;
    case ANCHOR_END_BUF:          fputs("end buf",        f); break;
    case ANCHOR_BEGIN_LINE:       fputs("begin line",     f); break;
    case ANCHOR_END_LINE:         fputs("end line",       f); break;
    case ANCHOR_SEMI_END_BUF:     fputs("semi end buf",   f); break;
    case ANCHOR_BEGIN_POSITION:   fputs("begin position", f); break;

    case ANCHOR_WORD_BOUNDARY:    fputs("word boundary",     f); break;
    case ANCHOR_NO_WORD_BOUNDARY: fputs("not word boundary", f); break;
#ifdef USE_WORD_BEGIN_END
    case ANCHOR_WORD_BEGIN:       fputs("word begin", f);     break;
    case ANCHOR_WORD_END:         fputs("word end", f);       break;
#endif
    case ANCHOR_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY:
      fputs("extended-grapheme-cluster boundary", f); break;
    case ANCHOR_NO_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY:
      fputs("no-extended-grapheme-cluster boundary", f); break;
    case ANCHOR_PREC_READ:
      fprintf(f, "prec read\n");
      print_indent_tree(f, NODE_BODY(node), indent + add);
      break;
    case ANCHOR_PREC_READ_NOT:
      fprintf(f, "prec read not\n");
      print_indent_tree(f, NODE_BODY(node), indent + add);
      break;
    case ANCHOR_LOOK_BEHIND:
      fprintf(f, "look behind\n");
      print_indent_tree(f, NODE_BODY(node), indent + add);
      break;
    case ANCHOR_LOOK_BEHIND_NOT:
      fprintf(f, "look behind not\n");
      print_indent_tree(f, NODE_BODY(node), indent + add);
      break;

    default:
      fprintf(f, "ERROR: undefined anchor type.\n");
      break;
    }
    break;

  case NODE_BACKREF:
    {
      int* p;
      BackRefNode* br = BACKREF_(node);
      p = BACKREFS_P(br);
      fprintf(f, "<backref%s:%p>", NODE_IS_CHECKER(node) ? "-checker" : "", node);
      for (i = 0; i < br->back_num; i++) {
        if (i > 0) fputs(", ", f);
        fprintf(f, "%d", p[i]);
      }
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    {
      CallNode* cn = CALL_(node);
      fprintf(f, "<call:%p>", node);
      p_string(f, cn->name_end - cn->name, cn->name);
    }
    break;
#endif

  case NODE_QUANT:
    fprintf(f, "<quantifier:%p>{%d,%d}%s\n", node,
            QUANT_(node)->lower, QUANT_(node)->upper,
            (QUANT_(node)->greedy ? "" : "?"));
    print_indent_tree(f, NODE_BODY(node), indent + add);
    break;

  case NODE_ENCLOSURE:
    fprintf(f, "<enclosure:%p> ", node);
    switch (ENCLOSURE_(node)->type) {
    case ENCLOSURE_OPTION:
      fprintf(f, "option:%d", ENCLOSURE_(node)->o.options);
      break;
    case ENCLOSURE_MEMORY:
      fprintf(f, "memory:%d", ENCLOSURE_(node)->m.regnum);
      break;
    case ENCLOSURE_STOP_BACKTRACK:
      fprintf(f, "stop-bt");
      break;

    default:
      break;
    }
    fprintf(f, "\n");
    print_indent_tree(f, NODE_BODY(node), indent + add);
    break;

  case NODE_GIMMICK:
    fprintf(f, "<gimmick:%p> ", node);
    switch (GIMMICK_(node)->type) {
    case GIMMICK_FAIL:
      fprintf(f, "fail");
      break;
    case GIMMICK_KEEP:
      fprintf(f, "keep:%d", GIMMICK_(node)->id);
      break;
    case GIMMICK_SAVE:
      fprintf(f, "save:%d:%d", GIMMICK_(node)->detail_type, GIMMICK_(node)->id);
      break;
    case GIMMICK_UPDATE_VAR:
      fprintf(f, "update_var:%d:%d", GIMMICK_(node)->detail_type, GIMMICK_(node)->id);
      break;
#ifdef USE_CALLOUT
    case GIMMICK_CALLOUT:
      switch (GIMMICK_(node)->detail_type) {
      case ONIG_CALLOUT_OF_CONTENTS:
        fprintf(f, "callout:contents:%d", GIMMICK_(node)->num);
        break;
      case ONIG_CALLOUT_OF_NAME:
        fprintf(f, "callout:name:%d:%d", GIMMICK_(node)->id, GIMMICK_(node)->num);
        break;
      }
#endif
    }
    break;

  default:
    fprintf(f, "print_indent_tree: undefined node type %d\n", NODE_TYPE(node));
    break;
  }

  if (type != NODE_LIST && type != NODE_ALT && type != NODE_QUANT &&
      type != NODE_ENCLOSURE)
    fprintf(f, "\n");
  fflush(f);
}


compile_anchor_node(AnchorNode* node, regex_t* reg, ScanEnv* env)
{
  int r, len;
  enum OpCode op;

  switch (node->type) {
  case ANCHOR_BEGIN_BUF:      r = add_opcode(reg, OP_BEGIN_BUF);      break;
  case ANCHOR_END_BUF:        r = add_opcode(reg, OP_END_BUF);        break;
  case ANCHOR_BEGIN_LINE:     r = add_opcode(reg, OP_BEGIN_LINE);     break;
  case ANCHOR_END_LINE:       r = add_opcode(reg, OP_END_LINE);       break;
  case ANCHOR_SEMI_END_BUF:   r = add_opcode(reg, OP_SEMI_END_BUF);   break;
  case ANCHOR_BEGIN_POSITION: r = add_opcode(reg, OP_BEGIN_POSITION); break;

  case ANCHOR_WORD_BOUNDARY:
    op = OP_WORD_BOUNDARY;
  word:
    r = add_opcode(reg, op);
    if (r != 0) return r;
    r = add_mode(reg, (ModeType )node->ascii_mode);
    break;

  case ANCHOR_NO_WORD_BOUNDARY:
    op = OP_NO_WORD_BOUNDARY; goto word;
    break;
#ifdef USE_WORD_BEGIN_END
  case ANCHOR_WORD_BEGIN:
    op = OP_WORD_BEGIN; goto word;
    break;
  case ANCHOR_WORD_END:
    op = OP_WORD_END; goto word;
    break;
#endif

  case ANCHOR_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY:
    r = add_opcode(reg, OP_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY);
    break;

  case ANCHOR_NO_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY:
    r = add_opcode(reg, OP_NO_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY);
    break;

  case ANCHOR_PREC_READ:
    r = add_opcode(reg, OP_PREC_READ_START);
    if (r != 0) return r;
    r = compile_tree(NODE_ANCHOR_BODY(node), reg, env);
    if (r != 0) return r;
    r = add_opcode(reg, OP_PREC_READ_END);
    break;

  case ANCHOR_PREC_READ_NOT:
    len = compile_length_tree(NODE_ANCHOR_BODY(node), reg);
    if (len < 0) return len;
    r = add_opcode_rel_addr(reg, OP_PREC_READ_NOT_START, len + SIZE_OP_PREC_READ_NOT_END);
    if (r != 0) return r;
    r = compile_tree(NODE_ANCHOR_BODY(node), reg, env);
    if (r != 0) return r;
    r = add_opcode(reg, OP_PREC_READ_NOT_END);
    break;

  case ANCHOR_LOOK_BEHIND:
    {
      int n;
      r = add_opcode(reg, OP_LOOK_BEHIND);
      if (r != 0) return r;
      if (node->char_len < 0) {
        r = get_char_length_tree(NODE_ANCHOR_BODY(node), reg, &n);
        if (r != 0) return ONIGERR_INVALID_LOOK_BEHIND_PATTERN;
      }
      else
        n = node->char_len;

      r = add_length(reg, n);
      if (r != 0) return r;
      r = compile_tree(NODE_ANCHOR_BODY(node), reg, env);
    }
    break;

  case ANCHOR_LOOK_BEHIND_NOT:
    {
      int n;

      len = compile_length_tree(NODE_ANCHOR_BODY(node), reg);
      r = add_opcode_rel_addr(reg, OP_LOOK_BEHIND_NOT_START,
                              len + SIZE_OP_LOOK_BEHIND_NOT_END);
      if (r != 0) return r;
      if (node->char_len < 0) {
        r = get_char_length_tree(NODE_ANCHOR_BODY(node), reg, &n);
        if (r != 0) return ONIGERR_INVALID_LOOK_BEHIND_PATTERN;
      }
      else
        n = node->char_len;
      r = add_length(reg, n);
      if (r != 0) return r;
      r = compile_tree(NODE_ANCHOR_BODY(node), reg, env);
      if (r != 0) return r;
      r = add_opcode(reg, OP_LOOK_BEHIND_NOT_END);
    }
    break;

  default:
    return ONIGERR_TYPE_BUG;
    break;
  }

  return r;
}


set_sunday_quick_search_skip_table(UChar* s, UChar* end, OnigEncoding enc,
                                   UChar skip[], int* roffset)
{
  int i, len, offset;

  offset = 1;
  if (ONIGENC_MBC_MINLEN(enc) > 1) {
    UChar* p = s;
    while (1) {
      len = enclen(enc, p);
      if (p + len >= end) {
        UChar* q = p + (ONIGENC_MBC_MINLEN(enc) - 1);
        while (q > p) {
          if (*q != '\0') {
            offset = q - p + 1;
            break;
          }
          q--;
        }
        break;
      }
      p += len;
    }
  }

  len = (int )(end - s);
  if (len + offset >= ONIG_CHAR_TABLE_SIZE)
    return ONIGERR_PARSER_BUG;

  *roffset = offset;

  for (i = 0; i < ONIG_CHAR_TABLE_SIZE; i++) skip[i] = (UChar )(len + offset);

  for (i = 0; i < len; i++)
    skip[s[i]] = len - i + (offset - 1);

  return 0;
}


add_rel_addr(regex_t* reg, int addr)
{
  RelAddrType ra = (RelAddrType )addr;

  BB_ADD(reg, &ra, SIZE_RELADDR);
  return 0;
}


expand_case_fold_make_rem_string(Node** rnode, UChar *s, UChar *end, regex_t* reg)
{
  int r;
  Node *node;

  node = onig_node_new_str(s, end);
  if (IS_NULL(node)) return ONIGERR_MEMORY;

  r = update_string_node_case_fold(reg, node);
  if (r != 0) {
    onig_node_free(node);
    return r;
  }

  NODE_STRING_SET_AMBIG(node);
  NODE_STRING_SET_DONT_GET_OPT_INFO(node);
  *rnode = node;
  return 0;
}


get_head_value_node(Node* node, int exact, regex_t* reg)
{
  Node* n = NULL_NODE;

  switch (NODE_TYPE(node)) {
  case NODE_BACKREF:
  case NODE_ALT:
#ifdef USE_CALL
  case NODE_CALL:
#endif
    break;

  case NODE_CTYPE:
    if (CTYPE_(node)->ctype == CTYPE_ANYCHAR)
      break;
    /* fall */
  case NODE_CCLASS:
    if (exact == 0) {
      n = node;
    }
    break;

  case NODE_LIST:
    n = get_head_value_node(NODE_CAR(node), exact, reg);
    break;

  case NODE_STRING:
    {
      StrNode* sn = STR_(node);

      if (sn->end <= sn->s)
        break;

      if (exact == 0 ||
          ! IS_IGNORECASE(reg->options) || NODE_STRING_IS_RAW(node)) {
        n = node;
      }
    }
    break;

  case NODE_QUANT:
    {
      QuantNode* qn = QUANT_(node);
      if (qn->lower > 0) {
        if (IS_NOT_NULL(qn->head_exact))
          n = qn->head_exact;
        else
          n = get_head_value_node(NODE_BODY(node), exact, reg);
      }
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);
      switch (en->type) {
      case ENCLOSURE_OPTION:
        {
          OnigOptionType options = reg->options;

          reg->options = ENCLOSURE_(node)->o.options;
          n = get_head_value_node(NODE_BODY(node), exact, reg);
          reg->options = options;
        }
        break;

      case ENCLOSURE_MEMORY:
      case ENCLOSURE_STOP_BACKTRACK:
      case ENCLOSURE_IF_ELSE:
        n = get_head_value_node(NODE_BODY(node), exact, reg);
        break;
      }
    }
    break;

  case NODE_ANCHOR:
    if (ANCHOR_(node)->type == ANCHOR_PREC_READ)
      n = get_head_value_node(NODE_BODY(node), exact, reg);
    break;

  case NODE_GIMMICK:
  default:
    break;
  }

  return n;
}


static void print_enc_string(FILE* fp, OnigEncoding enc,
                             const UChar *s, const UChar *end)
{
  fprintf(fp, "\nPATTERN: /");

  if (ONIGENC_MBC_MINLEN(enc) > 1) {
    const UChar *p;
    OnigCodePoint code;

    p = s;
    while (p < end) {
      code = ONIGENC_MBC_TO_CODE(enc, p, end);
      if (code >= 0x80) {
        fprintf(fp, " 0x%04x ", (int )code);
      }
      else {
        fputc((int )code, fp);
      }

      p += enclen(enc, p);
    }
  }
  else {
    while (s < end) {
      fputc((int )*s, fp);
      s++;
    }
  }

  fprintf(fp, "/\n");
}


add_length(regex_t* reg, int len)
{
  LengthType l = (LengthType )len;

  BB_ADD(reg, &l, SIZE_LENGTH);
  return 0;
}


concat_opt_anc_info(OptAnc* to, OptAnc* left, OptAnc* right,
                    OnigLen left_len, OnigLen right_len)
{
  clear_opt_anc_info(to);

  to->left = left->left;
  if (left_len == 0) {
    to->left |= right->left;
  }

  to->right = right->right;
  if (right_len == 0) {
    to->right |= left->right;
  }
  else {
    to->right |= (left->right & ANCHOR_PREC_READ_NOT);
  }
}


onig_compile(regex_t* reg, const UChar* pattern, const UChar* pattern_end,
             OnigErrorInfo* einfo)
{
#define COMPILE_INIT_SIZE  20

  int r, init_size;
  Node*  root;
  ScanEnv  scan_env;
#ifdef USE_CALL
  UnsetAddrList  uslist;
#endif

  root = 0;
  if (IS_NOT_NULL(einfo)) {
    einfo->enc = reg->enc;
    einfo->par = (UChar* )NULL;
  }

#ifdef ONIG_DEBUG
  print_enc_string(stderr, reg->enc, pattern, pattern_end);
#endif

  if (reg->alloc == 0) {
    init_size = (int )(pattern_end - pattern) * 2;
    if (init_size <= 0) init_size = COMPILE_INIT_SIZE;
    r = BB_INIT(reg, init_size);
    if (r != 0) goto end;
  }
  else
    reg->used = 0;

  reg->num_mem            = 0;
  reg->num_repeat         = 0;
  reg->num_null_check     = 0;
  reg->repeat_range_alloc = 0;
  reg->repeat_range       = (OnigRepeatRange* )NULL;

  r = onig_parse_tree(&root, pattern, pattern_end, reg, &scan_env);
  if (r != 0) goto err;

  /* mixed use named group and no-named group */
  if (scan_env.num_named > 0 &&
      IS_SYNTAX_BV(scan_env.syntax, ONIG_SYN_CAPTURE_ONLY_NAMED_GROUP) &&
      ! ONIG_IS_OPTION_ON(reg->options, ONIG_OPTION_CAPTURE_GROUP)) {
    if (scan_env.num_named != scan_env.num_mem)
      r = disable_noname_group_capture(&root, reg, &scan_env);
    else
      r = numbered_ref_check(root);

    if (r != 0) goto err;
  }

  r = check_backrefs(root, &scan_env);
  if (r != 0) goto err;

#ifdef USE_CALL
  if (scan_env.num_call > 0) {
    r = unset_addr_list_init(&uslist, scan_env.num_call);
    if (r != 0) goto err;
    scan_env.unset_addr_list = &uslist;
    r = setup_call(root, &scan_env, 0);
    if (r != 0) goto err_unset;
    r = setup_call2(root);
    if (r != 0) goto err_unset;
    r = recursive_call_check_trav(root, &scan_env, 0);
    if (r  < 0) goto err_unset;
    r = infinite_recursive_call_check_trav(root, &scan_env);
    if (r != 0) goto err_unset;

    setup_called_state(root, 0);
  }

  reg->num_call = scan_env.num_call;
#endif

  r = setup_tree(root, reg, 0, &scan_env);
  if (r != 0) goto err_unset;

#ifdef ONIG_DEBUG_PARSE
  print_tree(stderr, root);
#endif

  reg->capture_history  = scan_env.capture_history;
  reg->bt_mem_start     = scan_env.bt_mem_start;
  reg->bt_mem_start    |= reg->capture_history;
  if (IS_FIND_CONDITION(reg->options))
    MEM_STATUS_ON_ALL(reg->bt_mem_end);
  else {
    reg->bt_mem_end  = scan_env.bt_mem_end;
    reg->bt_mem_end |= reg->capture_history;
  }
  reg->bt_mem_start |= reg->bt_mem_end;

  clear_optimize_info(reg);
#ifndef ONIG_DONT_OPTIMIZE
  r = set_optimize_info_from_tree(root, reg, &scan_env);
  if (r != 0) goto err_unset;
#endif

  if (IS_NOT_NULL(scan_env.mem_env_dynamic)) {
    xfree(scan_env.mem_env_dynamic);
    scan_env.mem_env_dynamic = (MemEnv* )NULL;
  }

  r = compile_tree(root, reg, &scan_env);
  if (r == 0) {
    if (scan_env.keep_num > 0) {
      r = add_opcode(reg, OP_UPDATE_VAR);
      if (r != 0) goto err;
      r = add_update_var_type(reg, UPDATE_VAR_KEEP_FROM_STACK_LAST);
      if (r != 0) goto err;
      r = add_mem_num(reg, 0 /* not used */);
      if (r != 0) goto err;
    }

    r = add_opcode(reg, OP_END);
#ifdef USE_CALL
    if (scan_env.num_call > 0) {
      r = fix_unset_addr_list(&uslist, reg);
      unset_addr_list_end(&uslist);
      if (r != 0) goto err;
    }
#endif

    if ((reg->num_repeat != 0) || (reg->bt_mem_end != 0)
#ifdef USE_CALLOUT
        || (IS_NOT_NULL(reg->extp) && reg->extp->callout_num != 0)
#endif
        )
      reg->stack_pop_level = STACK_POP_LEVEL_ALL;
    else {
      if (reg->bt_mem_start != 0)
        reg->stack_pop_level = STACK_POP_LEVEL_MEM_START;
      else
        reg->stack_pop_level = STACK_POP_LEVEL_FREE;
    }
  }
#ifdef USE_CALL
  else if (scan_env.num_call > 0) {
    unset_addr_list_end(&uslist);
  }
#endif
  onig_node_free(root);

#ifdef ONIG_DEBUG_COMPILE
  onig_print_names(stderr, reg);
  onig_print_compiled_byte_code_list(stderr, reg);
#endif

 end:
  return r;

 err_unset:
#ifdef USE_CALL
  if (scan_env.num_call > 0) {
    unset_addr_list_end(&uslist);
  }
#endif
 err:
  if (IS_NOT_NULL(scan_env.error)) {
    if (IS_NOT_NULL(einfo)) {
      einfo->par     = scan_env.error;
      einfo->par_end = scan_env.error_end;
    }
  }

  onig_node_free(root);
  if (IS_NOT_NULL(scan_env.mem_env_dynamic))
      xfree(scan_env.mem_env_dynamic);
  return r;
}


compile_length_anchor_node(AnchorNode* node, regex_t* reg)
{
  int len;
  int tlen = 0;

  if (IS_NOT_NULL(NODE_ANCHOR_BODY(node))) {
    tlen = compile_length_tree(NODE_ANCHOR_BODY(node), reg);
    if (tlen < 0) return tlen;
  }

  switch (node->type) {
  case ANCHOR_PREC_READ:
    len = SIZE_OP_PREC_READ_START + tlen + SIZE_OP_PREC_READ_END;
    break;
  case ANCHOR_PREC_READ_NOT:
    len = SIZE_OP_PREC_READ_NOT_START + tlen + SIZE_OP_PREC_READ_NOT_END;
    break;
  case ANCHOR_LOOK_BEHIND:
    len = SIZE_OP_LOOK_BEHIND + tlen;
    break;
  case ANCHOR_LOOK_BEHIND_NOT:
    len = SIZE_OP_LOOK_BEHIND_NOT_START + tlen + SIZE_OP_LOOK_BEHIND_NOT_END;
    break;

  case ANCHOR_WORD_BOUNDARY:
  case ANCHOR_NO_WORD_BOUNDARY:
#ifdef USE_WORD_BEGIN_END
  case ANCHOR_WORD_BEGIN:
  case ANCHOR_WORD_END:
#endif
    len = SIZE_OP_WORD_BOUNDARY;
    break;

  case ANCHOR_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY:
  case ANCHOR_NO_EXTENDED_GRAPHEME_CLUSTER_BOUNDARY:
    len = SIZE_OPCODE;
    break;

  default:
    len = SIZE_OPCODE;
    break;
  }

  return len;
}


alt_merge_mml(MinMax* to, MinMax* from)
{
  if (to->min > from->min) to->min = from->min;
  if (to->max < from->max) to->max = from->max;
}


compile_length_option_node(EnclosureNode* node, regex_t* reg)
{
  int tlen;
  OnigOptionType prev = reg->options;

  reg->options = node->o.options;
  tlen = compile_length_tree(NODE_ENCLOSURE_BODY(node), reg);
  reg->options = prev;

  return tlen;
}


next_setup(Node* node, Node* next_node, regex_t* reg)
{
  NodeType type;

 retry:
  type = NODE_TYPE(node);
  if (type == NODE_QUANT) {
    QuantNode* qn = QUANT_(node);
    if (qn->greedy && IS_REPEAT_INFINITE(qn->upper)) {
#ifdef USE_QUANT_PEEK_NEXT
      Node* n = get_head_value_node(next_node, 1, reg);
      /* '\0': for UTF-16BE etc... */
      if (IS_NOT_NULL(n) && STR_(n)->s[0] != '\0') {
        qn->next_head_exact = n;
      }
#endif
      /* automatic posseivation a*b ==> (?>a*)b */
      if (qn->lower <= 1) {
        if (NODE_IS_SIMPLE_TYPE(NODE_BODY(node))) {
          Node *x, *y;
          x = get_head_value_node(NODE_BODY(node), 0, reg);
          if (IS_NOT_NULL(x)) {
            y = get_head_value_node(next_node,  0, reg);
            if (IS_NOT_NULL(y) && is_exclusive(x, y, reg)) {
              Node* en = onig_node_new_enclosure(ENCLOSURE_STOP_BACKTRACK);
              CHECK_NULL_RETURN_MEMERR(en);
              NODE_STATUS_ADD(en, STOP_BT_SIMPLE_REPEAT);
              swap_node(node, en);
              NODE_BODY(node) = en;
            }
          }
        }
      }
    }
  }
  else if (type == NODE_ENCLOSURE) {
    EnclosureNode* en = ENCLOSURE_(node);
    if (en->type == ENCLOSURE_MEMORY) {
      node = NODE_BODY(node);
      goto retry;
    }
  }
  return 0;
}


add_option(regex_t* reg, OnigOptionType option)
{
  BB_ADD(reg, &option, SIZE_OPTION);
  return 0;
}


compile_enclosure_memory_node(EnclosureNode* node, regex_t* reg, ScanEnv* env)
{
  int r;
  int len;

#ifdef USE_CALL
  if (node->m.regnum == 0 && NODE_IS_CALLED(node)) {
    r = add_opcode(reg, OP_CALL);
    if (r != 0) return r;
    node->m.called_addr = BB_GET_OFFSET_POS(reg) + SIZE_ABSADDR + SIZE_OP_JUMP;
    NODE_STATUS_ADD(node, ADDR_FIXED);
    r = add_abs_addr(reg, (int )node->m.called_addr);
    if (r != 0) return r;
    len = compile_length_tree(NODE_ENCLOSURE_BODY(node), reg);
    len += SIZE_OP_RETURN;
    r = add_opcode_rel_addr(reg, OP_JUMP, len);
    if (r != 0) return r;

    r = compile_tree(NODE_ENCLOSURE_BODY(node), reg, env);
    if (r != 0) return r;
    r = add_opcode(reg, OP_RETURN);
    return r;
  }

  if (NODE_IS_CALLED(node)) {
    r = add_opcode(reg, OP_CALL);
    if (r != 0) return r;
    node->m.called_addr = BB_GET_OFFSET_POS(reg) + SIZE_ABSADDR + SIZE_OP_JUMP;
    NODE_STATUS_ADD(node, ADDR_FIXED);
    r = add_abs_addr(reg, (int )node->m.called_addr);
    if (r != 0) return r;
    len = compile_length_tree(NODE_ENCLOSURE_BODY(node), reg);
    len += (SIZE_OP_MEMORY_START_PUSH + SIZE_OP_RETURN);
    if (MEM_STATUS_AT0(reg->bt_mem_end, node->m.regnum))
      len += (NODE_IS_RECURSION(node)
              ? SIZE_OP_MEMORY_END_PUSH_REC : SIZE_OP_MEMORY_END_PUSH);
    else
      len += (NODE_IS_RECURSION(node)
              ? SIZE_OP_MEMORY_END_REC : SIZE_OP_MEMORY_END);

    r = add_opcode_rel_addr(reg, OP_JUMP, len);
    if (r != 0) return r;
  }
#endif

  if (MEM_STATUS_AT0(reg->bt_mem_start, node->m.regnum))
    r = add_opcode(reg, OP_MEMORY_START_PUSH);
  else
    r = add_opcode(reg, OP_MEMORY_START);
  if (r != 0) return r;
  r = add_mem_num(reg, node->m.regnum);
  if (r != 0) return r;
  r = compile_tree(NODE_ENCLOSURE_BODY(node), reg, env);
  if (r != 0) return r;

#ifdef USE_CALL
  if (MEM_STATUS_AT0(reg->bt_mem_end, node->m.regnum))
    r = add_opcode(reg, (NODE_IS_RECURSION(node)
                         ? OP_MEMORY_END_PUSH_REC : OP_MEMORY_END_PUSH));
  else
    r = add_opcode(reg, (NODE_IS_RECURSION(node)
                         ? OP_MEMORY_END_REC : OP_MEMORY_END));
  if (r != 0) return r;
  r = add_mem_num(reg, node->m.regnum);
  if (NODE_IS_CALLED(node)) {
    if (r != 0) return r;
    r = add_opcode(reg, OP_RETURN);
  }
#else
  if (MEM_STATUS_AT0(reg->bt_mem_end, node->m.regnum))
    r = add_opcode(reg, OP_MEMORY_END_PUSH);
  else
    r = add_opcode(reg, OP_MEMORY_END);
  if (r != 0) return r;
  r = add_mem_num(reg, node->m.regnum);
#endif

  return r;
}


compile_quantifier_node(QuantNode* qn, regex_t* reg, ScanEnv* env)
{
  int i, r, mod_tlen;
  int infinite = IS_REPEAT_INFINITE(qn->upper);
  enum QuantBodyEmpty empty_info = qn->body_empty_info;
  int tlen = compile_length_tree(NODE_QUANT_BODY(qn), reg);

  if (tlen < 0) return tlen;
  if (tlen == 0) return 0;

  if (is_anychar_infinite_greedy(qn) &&
      (qn->lower <= 1 ||
       int_multiply_cmp(tlen, qn->lower, QUANTIFIER_EXPAND_LIMIT_SIZE) <= 0)) {
    r = compile_tree_n_times(NODE_QUANT_BODY(qn), qn->lower, reg, env);
    if (r != 0) return r;
    if (IS_NOT_NULL(qn->next_head_exact)) {
      if (IS_MULTILINE(CTYPE_OPTION(NODE_QUANT_BODY(qn), reg)))
        r = add_opcode(reg, OP_ANYCHAR_ML_STAR_PEEK_NEXT);
      else
        r = add_opcode(reg, OP_ANYCHAR_STAR_PEEK_NEXT);
      if (r != 0) return r;
      return add_bytes(reg, STR_(qn->next_head_exact)->s, 1);
    }
    else {
      if (IS_MULTILINE(CTYPE_OPTION(NODE_QUANT_BODY(qn), reg)))
        return add_opcode(reg, OP_ANYCHAR_ML_STAR);
      else
        return add_opcode(reg, OP_ANYCHAR_STAR);
    }
  }

  if (empty_info == QUANT_BODY_IS_NOT_EMPTY)
    mod_tlen = tlen;
  else
    mod_tlen = tlen + (SIZE_OP_EMPTY_CHECK_START + SIZE_OP_EMPTY_CHECK_END);

  if (infinite &&
      (qn->lower <= 1 ||
       int_multiply_cmp(tlen, qn->lower, QUANTIFIER_EXPAND_LIMIT_SIZE) <= 0)) {
    if (qn->lower == 1 && tlen > QUANTIFIER_EXPAND_LIMIT_SIZE) {
      if (qn->greedy) {
        if (IS_NOT_NULL(qn->head_exact))
          r = add_opcode_rel_addr(reg, OP_JUMP, SIZE_OP_PUSH_OR_JUMP_EXACT1);
        else if (IS_NOT_NULL(qn->next_head_exact))
          r = add_opcode_rel_addr(reg, OP_JUMP, SIZE_OP_PUSH_IF_PEEK_NEXT);
        else
          r = add_opcode_rel_addr(reg, OP_JUMP, SIZE_OP_PUSH);
      }
      else {
        r = add_opcode_rel_addr(reg, OP_JUMP, SIZE_OP_JUMP);
      }
      if (r != 0) return r;
    }
    else {
      r = compile_tree_n_times(NODE_QUANT_BODY(qn), qn->lower, reg, env);
      if (r != 0) return r;
    }

    if (qn->greedy) {
      if (IS_NOT_NULL(qn->head_exact)) {
        r = add_opcode_rel_addr(reg, OP_PUSH_OR_JUMP_EXACT1,
                                mod_tlen + SIZE_OP_JUMP);
        if (r != 0) return r;
        add_bytes(reg, STR_(qn->head_exact)->s, 1);
        r = compile_tree_empty_check(NODE_QUANT_BODY(qn), reg, empty_info, env);
        if (r != 0) return r;
        r = add_opcode_rel_addr(reg, OP_JUMP,
           -(mod_tlen + (int )SIZE_OP_JUMP + (int )SIZE_OP_PUSH_OR_JUMP_EXACT1));
      }
      else if (IS_NOT_NULL(qn->next_head_exact)) {
        r = add_opcode_rel_addr(reg, OP_PUSH_IF_PEEK_NEXT,
                                mod_tlen + SIZE_OP_JUMP);
        if (r != 0) return r;
        add_bytes(reg, STR_(qn->next_head_exact)->s, 1);
        r = compile_tree_empty_check(NODE_QUANT_BODY(qn), reg, empty_info, env);
        if (r != 0) return r;
        r = add_opcode_rel_addr(reg, OP_JUMP,
           -(mod_tlen + (int )SIZE_OP_JUMP + (int )SIZE_OP_PUSH_IF_PEEK_NEXT));
      }
      else {
        r = add_opcode_rel_addr(reg, OP_PUSH, mod_tlen + SIZE_OP_JUMP);
        if (r != 0) return r;
        r = compile_tree_empty_check(NODE_QUANT_BODY(qn), reg, empty_info, env);
        if (r != 0) return r;
        r = add_opcode_rel_addr(reg, OP_JUMP,
                   -(mod_tlen + (int )SIZE_OP_JUMP + (int )SIZE_OP_PUSH));
      }
    }
    else {
      r = add_opcode_rel_addr(reg, OP_JUMP, mod_tlen);
      if (r != 0) return r;
      r = compile_tree_empty_check(NODE_QUANT_BODY(qn), reg, empty_info, env);
      if (r != 0) return r;
      r = add_opcode_rel_addr(reg, OP_PUSH, -(mod_tlen + (int )SIZE_OP_PUSH));
    }
  }
  else if (qn->upper == 0 && qn->is_refered != 0) { /* /(?<n>..){0}/ */
    r = add_opcode_rel_addr(reg, OP_JUMP, tlen);
    if (r != 0) return r;
    r = compile_tree(NODE_QUANT_BODY(qn), reg, env);
  }
  else if (! infinite && qn->greedy &&
           (qn->upper == 1 ||
            int_multiply_cmp(tlen + SIZE_OP_PUSH, qn->upper,
                             QUANTIFIER_EXPAND_LIMIT_SIZE) <= 0)) {
    int n = qn->upper - qn->lower;

    r = compile_tree_n_times(NODE_QUANT_BODY(qn), qn->lower, reg, env);
    if (r != 0) return r;

    for (i = 0; i < n; i++) {
      int v = onig_positive_int_multiply(n - i, tlen);
      if (v < 0) return ONIGERR_TOO_BIG_NUMBER_FOR_REPEAT_RANGE;
      r = add_opcode_rel_addr(reg, OP_PUSH, v + (n - i - 1) * SIZE_OP_PUSH);
      if (r != 0) return r;
      r = compile_tree(NODE_QUANT_BODY(qn), reg, env);
      if (r != 0) return r;
    }
  }
  else if (! qn->greedy && qn->upper == 1 && qn->lower == 0) { /* '??' */
    r = add_opcode_rel_addr(reg, OP_PUSH, SIZE_OP_JUMP);
    if (r != 0) return r;
    r = add_opcode_rel_addr(reg, OP_JUMP, tlen);
    if (r != 0) return r;
    r = compile_tree(NODE_QUANT_BODY(qn), reg, env);
  }
  else {
    r = compile_range_repeat_node(qn, mod_tlen, empty_info, reg, env);
  }
  return r;
}


clear_node_opt_info(NodeOpt* opt)
{
  clear_mml(&opt->len);
  clear_opt_anc_info(&opt->anc);
  clear_opt_exact(&opt->exb);
  clear_opt_exact(&opt->exm);
  clear_opt_exact(&opt->expr);
  clear_opt_map(&opt->map);
}


set_optimize_exact(regex_t* reg, OptExact* e)
{
  int r;

  if (e->len == 0) return 0;

  if (e->ignore_case) {
    reg->exact = (UChar* )xmalloc(e->len);
    CHECK_NULL_RETURN_MEMERR(reg->exact);
    xmemcpy(reg->exact, e->s, e->len);
    reg->exact_end = reg->exact + e->len;
    reg->optimize = OPTIMIZE_STR_IC;
  }
  else {
    int allow_reverse;

    reg->exact = onigenc_strdup(reg->enc, e->s, e->s + e->len);
    CHECK_NULL_RETURN_MEMERR(reg->exact);
    reg->exact_end = reg->exact + e->len;

    allow_reverse =
      ONIGENC_IS_ALLOWED_REVERSE_MATCH(reg->enc, reg->exact, reg->exact_end);

    if (e->len >= 3 || (e->len >= 2 && allow_reverse)) {
#ifdef USE_SUNDAY_QUICK_SEARCH_ALGORITHM
      r = set_sunday_quick_search_skip_table(reg->exact, reg->exact_end,
                                             reg->enc, reg->map,
                                             &(reg->map_offset));
#else
      r = set_bmh_search_skip_table(reg->exact, reg->exact_end,
                                    reg->enc, reg->map);
#endif
      if (r != 0) return r;

      reg->optimize = (allow_reverse != 0
                       ? OPTIMIZE_STR_FAST
                       : OPTIMIZE_STR_FAST_STEP_FORWARD);
    }
    else {
      reg->optimize = OPTIMIZE_STR;
    }
  }

  reg->dmin = e->mmd.min;
  reg->dmax = e->mmd.max;

  if (reg->dmin != INFINITE_LEN) {
    reg->threshold_len = reg->dmin + (int )(reg->exact_end - reg->exact);
  }

  return 0;
}


infinite_recursive_call_check_trav(Node* node, ScanEnv* env)
{
  int r;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    do {
      r = infinite_recursive_call_check_trav(NODE_CAR(node), env);
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_ANCHOR:
    if (! ANCHOR_HAS_BODY(ANCHOR_(node))) {
      r = 0;
      break;
    }
    /* fall */
  case NODE_QUANT:
    r = infinite_recursive_call_check_trav(NODE_BODY(node), env);
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      if (en->type == ENCLOSURE_MEMORY) {
        if (NODE_IS_RECURSION(node) && NODE_IS_CALLED(node)) {
          int ret;

          NODE_STATUS_ADD(node, MARK1);

          ret = infinite_recursive_call_check(NODE_BODY(node), env, 1);
          if (ret < 0) return ret;
          else if ((ret & (RECURSION_MUST | RECURSION_INFINITE)) != 0)
            return ONIGERR_NEVER_ENDING_RECURSION;

          NODE_STATUS_REMOVE(node, MARK1);
        }
      }
      else if (en->type == ENCLOSURE_IF_ELSE) {
        if (IS_NOT_NULL(en->te.Then)) {
          r = infinite_recursive_call_check_trav(en->te.Then, env);
          if (r != 0) return r;
        }
        if (IS_NOT_NULL(en->te.Else)) {
          r = infinite_recursive_call_check_trav(en->te.Else, env);
          if (r != 0) return r;
        }
      }
    }

    r = infinite_recursive_call_check_trav(NODE_BODY(node), env);
    break;

  default:
    r = 0;
    break;
  }

  return r;
}


concat_opt_exact_str(OptExact* to, UChar* s, UChar* end, OnigEncoding enc)
{
  int i, j, len;
  UChar *p;

  for (i = to->len, p = s; p < end && i < OPT_EXACT_MAXLEN; ) {
    len = enclen(enc, p);
    if (i + len > OPT_EXACT_MAXLEN) break;
    for (j = 0; j < len && p < end; j++)
      to->s[i++] = *p++;
  }

  to->len = i;
}


add_multi_byte_cclass(BBuf* mbuf, regex_t* reg)
{
#ifdef PLATFORM_UNALIGNED_WORD_ACCESS
  add_length(reg, mbuf->used);
  return add_bytes(reg, mbuf->p, mbuf->used);
#else
  int r, pad_size;
  UChar* p = BB_GET_ADD_ADDRESS(reg) + SIZE_LENGTH;

  GET_ALIGNMENT_PAD_SIZE(p, pad_size);
  add_length(reg, mbuf->used + (WORD_ALIGNMENT_SIZE - 1));
  if (pad_size != 0) add_bytes(reg, PadBuf, pad_size);

  r = add_bytes(reg, mbuf->p, mbuf->used);

  /* padding for return value from compile_length_cclass_node() to be fix. */
  pad_size = (WORD_ALIGNMENT_SIZE - 1) - pad_size;
  if (pad_size != 0) add_bytes(reg, PadBuf, pad_size);
  return r;
#endif
}


is_good_case_fold_items_for_search(OnigEncoding enc, int slen,
                                   int n, OnigCaseFoldCodeItem items[])
{
  int i, len;
  UChar buf[ONIGENC_MBC_CASE_FOLD_MAXLEN];

  for (i = 0; i < n; i++) {
    OnigCaseFoldCodeItem* item = items + i;

    if (item->code_len != 1)    return 0;
    if (item->byte_len != slen) return 0;
    len = ONIGENC_CODE_TO_MBC(enc, item->code[0], buf);
    if (len != slen) return 0;
  }

  return 1;
}


comp_distance_value(MinMax* d1, MinMax* d2, int v1, int v2)
{
  if (v2 <= 0) return -1;
  if (v1 <= 0) return  1;

  v1 *= distance_value(d1);
  v2 *= distance_value(d2);

  if (v2 > v1) return  1;
  if (v2 < v1) return -1;

  if (d2->min < d1->min) return  1;
  if (d2->min > d1->min) return -1;
  return 0;
}


clear_mml(MinMax* l)
{
  l->min = l->max = 0;
}


is_full_opt_exact(OptExact* e)
{
  return e->len >= OPT_EXACT_MAXLEN;
}


compile_tree_empty_check(Node* node, regex_t* reg, int empty_info, ScanEnv* env)
{
  int r;
  int saved_num_null_check = reg->num_null_check;

  if (empty_info != QUANT_BODY_IS_NOT_EMPTY) {
    r = add_opcode(reg, OP_EMPTY_CHECK_START);
    if (r != 0) return r;
    r = add_mem_num(reg, reg->num_null_check); /* NULL CHECK ID */
    if (r != 0) return r;
    reg->num_null_check++;
  }

  r = compile_tree(node, reg, env);
  if (r != 0) return r;

  if (empty_info != QUANT_BODY_IS_NOT_EMPTY) {
    if (empty_info == QUANT_BODY_IS_EMPTY)
      r = add_opcode(reg, OP_EMPTY_CHECK_END);
    else if (empty_info == QUANT_BODY_IS_EMPTY_MEM)
      r = add_opcode(reg, OP_EMPTY_CHECK_END_MEMST);
    else if (empty_info == QUANT_BODY_IS_EMPTY_REC)
      r = add_opcode(reg, OP_EMPTY_CHECK_END_MEMST_PUSH);

    if (r != 0) return r;
    r = add_mem_num(reg, saved_num_null_check); /* NULL CHECK ID */
  }
  return r;
}


alt_merge_node_opt_info(NodeOpt* to, NodeOpt* add, OptEnv* env)
{
  alt_merge_opt_anc_info(&to->anc, &add->anc);
  alt_merge_opt_exact(&to->exb,  &add->exb, env);
  alt_merge_opt_exact(&to->exm,  &add->exm, env);
  alt_merge_opt_exact(&to->expr, &add->expr, env);
  alt_merge_opt_map(env->enc, &to->map, &add->map);

  alt_merge_mml(&to->len, &add->len);
}


set_sub_anchor(regex_t* reg, OptAnc* anc)
{
  reg->sub_anchor |= anc->left  & ANCHOR_BEGIN_LINE;
  reg->sub_anchor |= anc->right & ANCHOR_END_LINE;
}


setup_call(Node* node, ScanEnv* env, int state)
{
  int r;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
  case NODE_ALT:
    do {
      r = setup_call(NODE_CAR(node), env, state);
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_QUANT:
    if (QUANT_(node)->upper == 0)
      state |= IN_ZERO_REPEAT;

    r = setup_call(NODE_BODY(node), env, state);
    break;

  case NODE_ANCHOR:
    if (ANCHOR_HAS_BODY(ANCHOR_(node)))
      r = setup_call(NODE_BODY(node), env, state);
    else
      r = 0;
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      if (en->type == ENCLOSURE_MEMORY) {
        if ((state & IN_ZERO_REPEAT) != 0) {
          NODE_STATUS_ADD(node, IN_ZERO_REPEAT);
          ENCLOSURE_(node)->m.entry_count--;
        }
        r = setup_call(NODE_BODY(node), env, state);
      }
      else if (en->type == ENCLOSURE_IF_ELSE) {
        r = setup_call(NODE_BODY(node), env, state);
        if (r != 0) return r;
        if (IS_NOT_NULL(en->te.Then)) {
          r = setup_call(en->te.Then, env, state);
          if (r != 0) return r;
        }
        if (IS_NOT_NULL(en->te.Else))
          r = setup_call(en->te.Else, env, state);
      }
      else
        r = setup_call(NODE_BODY(node), env, state);
    }
    break;

  case NODE_CALL:
    if ((state & IN_ZERO_REPEAT) != 0) {
      NODE_STATUS_ADD(node, IN_ZERO_REPEAT);
      CALL_(node)->entry_count--;
    }

    r = setup_call_node_call(CALL_(node), env, state);
    break;

  default:
    r = 0;
    break;
  }

  return r;
}


setup_tree(Node* node, regex_t* reg, int state, ScanEnv* env)
{
  int r = 0;

  switch (NODE_TYPE(node)) {
  case NODE_LIST:
    {
      Node* prev = NULL_NODE;
      do {
        r = setup_tree(NODE_CAR(node), reg, state, env);
        if (IS_NOT_NULL(prev) && r == 0) {
          r = next_setup(prev, NODE_CAR(node), reg);
        }
        prev = NODE_CAR(node);
      } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    }
    break;

  case NODE_ALT:
    do {
      r = setup_tree(NODE_CAR(node), reg, (state | IN_ALT), env);
    } while (r == 0 && IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_STRING:
    if (IS_IGNORECASE(reg->options) && !NODE_STRING_IS_RAW(node)) {
      r = expand_case_fold_string(node, reg);
    }
    break;

  case NODE_BACKREF:
    {
      int i;
      int* p;
      BackRefNode* br = BACKREF_(node);
      p = BACKREFS_P(br);
      for (i = 0; i < br->back_num; i++) {
        if (p[i] > env->num_mem)  return ONIGERR_INVALID_BACKREF;
        MEM_STATUS_ON(env->backrefed_mem, p[i]);
        MEM_STATUS_ON(env->bt_mem_start, p[i]);
#ifdef USE_BACKREF_WITH_LEVEL
        if (NODE_IS_NEST_LEVEL(node)) {
          MEM_STATUS_ON(env->bt_mem_end, p[i]);
        }
#endif
      }
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);

      switch (en->type) {
      case ENCLOSURE_OPTION:
        {
          OnigOptionType options = reg->options;
          reg->options = ENCLOSURE_(node)->o.options;
          r = setup_tree(NODE_BODY(node), reg, state, env);
          reg->options = options;
        }
        break;

      case ENCLOSURE_MEMORY:
#ifdef USE_CALL
        state |= en->m.called_state;
#endif

        if ((state & (IN_ALT | IN_NOT | IN_VAR_REPEAT | IN_MULTI_ENTRY)) != 0
            || NODE_IS_RECURSION(node)) {
          MEM_STATUS_ON(env->bt_mem_start, en->m.regnum);
        }
        r = setup_tree(NODE_BODY(node), reg, state, env);
        break;

      case ENCLOSURE_STOP_BACKTRACK:
        {
          Node* target = NODE_BODY(node);
          r = setup_tree(target, reg, state, env);
          if (NODE_TYPE(target) == NODE_QUANT) {
            QuantNode* tqn = QUANT_(target);
            if (IS_REPEAT_INFINITE(tqn->upper) && tqn->lower <= 1 &&
                tqn->greedy != 0) {  /* (?>a*), a*+ etc... */
              if (NODE_IS_SIMPLE_TYPE(NODE_BODY(target)))
                NODE_STATUS_ADD(node, STOP_BT_SIMPLE_REPEAT);
            }
          }
        }
        break;

      case ENCLOSURE_IF_ELSE:
        r = setup_tree(NODE_BODY(node), reg, (state | IN_ALT), env);
        if (r != 0) return r;
        if (IS_NOT_NULL(en->te.Then)) {
          r = setup_tree(en->te.Then, reg, (state | IN_ALT), env);
          if (r != 0) return r;
        }
        if (IS_NOT_NULL(en->te.Else))
          r = setup_tree(en->te.Else, reg, (state | IN_ALT), env);
        break;
      }
    }
    break;

  case NODE_QUANT:
    r = setup_quant(node, reg, state, env);
    break;

  case NODE_ANCHOR:
    r = setup_anchor(node, reg, state, env);
    break;

#ifdef USE_CALL
  case NODE_CALL:
#endif
  case NODE_CTYPE:
  case NODE_CCLASS:
  case NODE_GIMMICK:
  default:
    break;
  }

  return r;
}


tree_max_len(Node* node, ScanEnv* env)
{
  OnigLen len;
  OnigLen tmax;

  len = 0;
  switch (NODE_TYPE(node)) {
  case NODE_LIST:
    do {
      tmax = tree_max_len(NODE_CAR(node), env);
      len = distance_add(len, tmax);
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_ALT:
    do {
      tmax = tree_max_len(NODE_CAR(node), env);
      if (len < tmax) len = tmax;
    } while (IS_NOT_NULL(node = NODE_CDR(node)));
    break;

  case NODE_STRING:
    {
      StrNode* sn = STR_(node);
      len = (OnigLen )(sn->end - sn->s);
    }
    break;

  case NODE_CTYPE:
  case NODE_CCLASS:
    len = ONIGENC_MBC_MAXLEN_DIST(env->enc);
    break;

  case NODE_BACKREF:
    if (! NODE_IS_CHECKER(node)) {
      int i;
      int* backs;
      MemEnv* mem_env = SCANENV_MEMENV(env);
      BackRefNode* br = BACKREF_(node);
      if (NODE_IS_RECURSION(node)) {
        len = INFINITE_LEN;
        break;
      }
      backs = BACKREFS_P(br);
      for (i = 0; i < br->back_num; i++) {
        tmax = tree_max_len(mem_env[backs[i]].node, env);
        if (len < tmax) len = tmax;
      }
    }
    break;

#ifdef USE_CALL
  case NODE_CALL:
    if (! NODE_IS_RECURSION(node))
      len = tree_max_len(NODE_BODY(node), env);
    else
      len = INFINITE_LEN;
    break;
#endif

  case NODE_QUANT:
    {
      QuantNode* qn = QUANT_(node);

      if (qn->upper != 0) {
        len = tree_max_len(NODE_BODY(node), env);
        if (len != 0) {
          if (! IS_REPEAT_INFINITE(qn->upper))
            len = distance_multiply(len, qn->upper);
          else
            len = INFINITE_LEN;
        }
      }
    }
    break;

  case NODE_ENCLOSURE:
    {
      EnclosureNode* en = ENCLOSURE_(node);
      switch (en->type) {
      case ENCLOSURE_MEMORY:
        if (NODE_IS_MAX_FIXED(node))
          len = en->max_len;
        else {
          if (NODE_IS_MARK1(node))
            len = INFINITE_LEN;
          else {
            NODE_STATUS_ADD(node, MARK1);
            len = tree_max_len(NODE_BODY(node), env);
            NODE_STATUS_REMOVE(node, MARK1);

            en->max_len = len;
            NODE_STATUS_ADD(node, MAX_FIXED);
          }
        }
        break;

      case ENCLOSURE_OPTION:
      case ENCLOSURE_STOP_BACKTRACK:
        len = tree_max_len(NODE_BODY(node), env);
        break;
      case ENCLOSURE_IF_ELSE:
        {
          OnigLen tlen, elen;

          len = tree_max_len(NODE_BODY(node), env);
          if (IS_NOT_NULL(en->te.Then)) {
            tlen = tree_max_len(en->te.Then, env);
            len = distance_add(len, tlen);
          }
          if (IS_NOT_NULL(en->te.Else))
            elen = tree_max_len(en->te.Else, env);
          else elen = 0;

          if (elen > len) len = elen;
        }
        break;
      }
    }
    break;

  case NODE_ANCHOR:
  case NODE_GIMMICK:
  default:
    break;
  }

  return len;
}


int_stack_pop(int_stack* s)
{
  int v;

#ifdef ONIG_DEBUG
  if (s->n <= 0) {
    fprintf(stderr, "int_stack_pop: fail empty. %p\n", s);
    return 0;
  }
#endif

  v = s->v[s->n];
  s->n--;
  return v;
}


is_left(int a)
{
  if (a == ANCHOR_END_BUF  || a == ANCHOR_SEMI_END_BUF ||
      a == ANCHOR_END_LINE || a == ANCHOR_PREC_READ || a == ANCHOR_PREC_READ_NOT)
    return 0;

  return 1;
}


set_bound_node_opt_info(NodeOpt* opt, MinMax* plen)
{
  copy_mml(&(opt->exb.mmd),  plen);
  copy_mml(&(opt->expr.mmd), plen);
  copy_mml(&(opt->map.mmd),  plen);
}


add_bytes(regex_t* reg, UChar* bytes, int len)
{
  BB_ADD(reg, bytes, len);
  return 0;
}


fix_unset_addr_list(UnsetAddrList* uslist, regex_t* reg)
{
  int i, offset;
  EnclosureNode* en;
  AbsAddrType addr;

  for (i = 0; i < uslist->num; i++) {
    if (! NODE_IS_ADDR_FIXED(uslist->us[i].target))
      return ONIGERR_PARSER_BUG;

    en = ENCLOSURE_(uslist->us[i].target);
    addr   = en->m.called_addr;
    offset = uslist->us[i].offset;

    BB_WRITE(reg, offset, &addr, SIZE_ABSADDR);
  }
  return 0;
}


add_pointer(regex_t* reg, void* addr)
{
  PointerType ptr = (PointerType )addr;

  BB_ADD(reg, &ptr, SIZE_POINTER);
  return 0;
}


compile_option_node(EnclosureNode* node, regex_t* reg, ScanEnv* env)
{
  int r;
  OnigOptionType prev = reg->options;

  reg->options = node->o.options;
  r = compile_tree(NODE_ENCLOSURE_BODY(node), reg, env);
  reg->options = prev;

  return r;
}


copy_mml(MinMax* to, MinMax* from)
{
  to->min = from->min;
  to->max = from->max;
}


add_update_var_type(regex_t* reg, enum UpdateVarType type)
{
  UpdateVarType t = (UpdateVarType )type;

  BB_ADD(reg, &t, SIZE_UPDATE_VAR_TYPE);
  return 0;
}


divide_look_behind_alternatives(Node* node)
{
  Node *head, *np, *insert_node;
  AnchorNode* an = ANCHOR_(node);
  int anc_type = an->type;

  head = NODE_ANCHOR_BODY(an);
  np = NODE_CAR(head);
  swap_node(node, head);
  NODE_CAR(node) = head;
  NODE_BODY(head) = np;

  np = node;
  while (IS_NOT_NULL(np = NODE_CDR(np))) {
    insert_node = onig_node_new_anchor(anc_type, an->ascii_mode);
    CHECK_NULL_RETURN_MEMERR(insert_node);
    NODE_BODY(insert_node) = NODE_CAR(np);
    NODE_CAR(np) = insert_node;
  }

  if (anc_type == ANCHOR_LOOK_BEHIND_NOT) {
    np = node;
    do {
      NODE_SET_TYPE(np, NODE_LIST);  /* alt -> list */
    } while (IS_NOT_NULL(np = NODE_CDR(np)));
  }
  return 0;
}


add_mode(regex_t* reg, ModeType mode)
{
  BB_ADD(reg, &mode, SIZE_MODE);
  return 0;
}


alt_merge_opt_map(OnigEncoding enc, OptMap* to, OptMap* add)
{
  int i, val;

  /* if (! is_equal_mml(&to->mmd, &add->mmd)) return ; */
  if (to->value == 0) return ;
  if (add->value == 0 || to->mmd.max < add->mmd.min) {
    clear_opt_map(to);
    return ;
  }

  alt_merge_mml(&to->mmd, &add->mmd);

  val = 0;
  for (i = 0; i < ONIG_CHAR_TABLE_SIZE; i++) {
    if (add->map[i])
      to->map[i] = 1;

    if (to->map[i])
      val += map_position_value(enc, i);
  }
  to->value = val;

  alt_merge_opt_anc_info(&to->anc, &add->anc);
}


setup_quant(Node* node, regex_t* reg, int state, ScanEnv* env)
{
  int r;
  OnigLen d;
  QuantNode* qn = QUANT_(node);
  Node* body = NODE_BODY(node);

  if ((state & IN_REAL_REPEAT) != 0) {
    NODE_STATUS_ADD(node, IN_REAL_REPEAT);
  }
  if ((state & IN_MULTI_ENTRY) != 0) {
    NODE_STATUS_ADD(node, IN_MULTI_ENTRY);
  }

  if (IS_REPEAT_INFINITE(qn->upper) || qn->upper >= 1) {
    d = tree_min_len(body, env);
    if (d == 0) {
#ifdef USE_INSISTENT_CHECK_CAPTURES_IN_EMPTY_REPEAT
      qn->body_empty_info = quantifiers_memory_node_info(body);
      if (qn->body_empty_info == QUANT_BODY_IS_EMPTY_REC) {
        if (NODE_TYPE(body) == NODE_ENCLOSURE &&
            ENCLOSURE_(body)->type == ENCLOSURE_MEMORY) {
          MEM_STATUS_ON(env->bt_mem_end, ENCLOSURE_(body)->m.regnum);
        }
      }
#else
      qn->body_empty_info = QUANT_BODY_IS_EMPTY;
#endif
    }
  }

  if (IS_REPEAT_INFINITE(qn->upper) || qn->upper >= 2)
    state |= IN_REAL_REPEAT;
  if (qn->lower != qn->upper)
    state |= IN_VAR_REPEAT;

  r = setup_tree(body, reg, state, env);
  if (r != 0) return r;

  /* expand string */
#define EXPAND_STRING_MAX_LENGTH  100
  if (NODE_TYPE(body) == NODE_STRING) {
    if (!IS_REPEAT_INFINITE(qn->lower) && qn->lower == qn->upper &&
        qn->lower > 1 && qn->lower <= EXPAND_STRING_MAX_LENGTH) {
      int len = NODE_STRING_LEN(body);
      StrNode* sn = STR_(body);

      if (len * qn->lower <= EXPAND_STRING_MAX_LENGTH) {
        int i, n = qn->lower;
        onig_node_conv_to_str_node(node, STR_(body)->flag);
        for (i = 0; i < n; i++) {
          r = onig_node_str_cat(node, sn->s, sn->end);
          if (r != 0) return r;
        }
        onig_node_free(body);
        return r;
      }
    }
  }

#ifdef USE_OP_PUSH_OR_JUMP_EXACT
  if (qn->greedy && (qn->body_empty_info != QUANT_BODY_IS_NOT_EMPTY)) {
    if (NODE_TYPE(body) == NODE_QUANT) {
      QuantNode* tqn = QUANT_(body);
      if (IS_NOT_NULL(tqn->head_exact)) {
        qn->head_exact  = tqn->head_exact;
        tqn->head_exact = NULL;
      }
    }
    else {
      qn->head_exact = get_head_value_node(NODE_BODY(node), 1, reg);
    }
  }
#endif

  return r;
}


onig_positive_int_multiply(int x, int y)
{
  if (x == 0 || y == 0) return 0;

  if (x < INT_MAX / y)
    return x * y;
  else
    return -1;
}


setup_call_node_call(CallNode* cn, ScanEnv* env, int state)
{
  MemEnv* mem_env = SCANENV_MEMENV(env);

  if (cn->by_number != 0) {
    int gnum = cn->group_num;

    if (env->num_named > 0 &&
        IS_SYNTAX_BV(env->syntax, ONIG_SYN_CAPTURE_ONLY_NAMED_GROUP) &&
        ! ONIG_IS_OPTION_ON(env->options, ONIG_OPTION_CAPTURE_GROUP)) {
      return ONIGERR_NUMBERED_BACKREF_OR_CALL_NOT_ALLOWED;
    }

    if (gnum > env->num_mem) {
      onig_scan_env_set_error_string(env, ONIGERR_UNDEFINED_GROUP_REFERENCE,
                                     cn->name, cn->name_end);
      return ONIGERR_UNDEFINED_GROUP_REFERENCE;
    }

  set_call_attr:
    NODE_CALL_BODY(cn) = mem_env[cn->group_num].node;
    if (IS_NULL(NODE_CALL_BODY(cn))) {
      onig_scan_env_set_error_string(env, ONIGERR_UNDEFINED_NAME_REFERENCE,
                                     cn->name, cn->name_end);
      return ONIGERR_UNDEFINED_NAME_REFERENCE;
    }
  }
  else {
    int *refs;

    int n = onig_name_to_group_numbers(env->reg, cn->name, cn->name_end, &refs);
    if (n <= 0) {
      onig_scan_env_set_error_string(env, ONIGERR_UNDEFINED_NAME_REFERENCE,
                                     cn->name, cn->name_end);
      return ONIGERR_UNDEFINED_NAME_REFERENCE;
    }
    else if (n > 1) {
      onig_scan_env_set_error_string(env, ONIGERR_MULTIPLEX_DEFINITION_NAME_CALL,
                                     cn->name, cn->name_end);
      return ONIGERR_MULTIPLEX_DEFINITION_NAME_CALL;
    }
    else {
      cn->group_num = refs[0];
      goto set_call_attr;
    }
  }

  return 0;
}