moebius库性能优化参考

moebius/Data/Convert/tmu.cpp

@@ -38,6 +38,9 @@ using lolly::data::to_Hex;
 using moebius::drd::STD_CODE;
 using moebius::drd::std_contains;
 
+// 成段 memcpy 直写目标串(定义见 tmu_writer::write 前)
+static void append_run (string& tmp, const char* src, int len);
+
 using namespace moebius;
 
 /******************************************************************************
@@ -285,17 +288,21 @@ tmu_reader::skip_blank () {
 
 string
 tmu_reader::decode (string s) {
-  int    i, n= N (s);
-  string r;
+  // 普通字符成段 memcpy 直写,转义字符单独处理
+  int         i, n= N (s), run= 0;
+  string      r;
+  const char* raw= s.begin ();
   for (i= 0; i < n; i++)
     if (((i + 1) < n) && (s[i] == '\\')) {
+      append_run (r, raw + run, i - run);
       i++;
       if (s[i] == ';')
         ;
       else if (s[i] == '\\') r << '\\';
       else r << s[i];
+      run= i + 1;
     }
-    else r << s[i];
+  append_run (r, raw + run, n - run);
   return r;
 }
 
@@ -352,28 +359,40 @@ tmu_reader::read_next () {
   }
 
   string r;
-  pos= old_pos;
-  while (true) {
-    old_pos= pos;
-    c      = read_char ();
-    if (c == "") return r;
-    else if (c == "\\") {
-      if ((pos < buf_N) && (buf[pos] == '\\')) {
-        r << c << "\\";
-        pos++;
+  // 字节级扫描代替逐字符 read_char:普通字符成段一次追加,
+  // 转义 '\\' 逐字保留并连同后续一个 utf8 序列一起复制,
+  // 免去原文档加载热路径上每字符一次的子串分配
+  pos    = old_pos;
+  int run= pos;
+  while (pos < buf_N) {
+    char b= buf[pos];
+    if (b == '\t' || b == '\r' || b == '\n' || b == ' ' || b == '<' ||
+        b == '|' || b == '>')
+      break;
+    if (b == '\\') {
+      append_run (r, buf.begin () + run, pos - run);
+      // 行续接 "\<newline>" 由 read_char 语义跳过
+      if ((pos + 1 < buf_N) && (buf[pos + 1] == '\n')) {
+        pos+= 2;
+        skip_spaces (buf, pos);
+        run= pos;
+        continue;
+      }
+      r << b;
+      pos++;
+      if (pos >= buf_N) {
+        run= pos;
+        break;
       }
-      else r << c << read_char ();
+      int start= pos;
+      decode_from_utf8 (buf, pos);
+      append_run (r, buf.begin () + start, pos - start);
+      run= pos;
+      continue;
     }
-    else if (c == "\t") break;
-    else if (c == "\r") break;
-    else if (c == "\n") break;
-    else if (c == " ") break;
-    else if (c == "<") break;
-    else if (c == "|") break;
-    else if (c == ">") break;
-    else r << c;
+    decode_from_utf8 (buf, pos);
   }
-  pos= old_pos;
+  append_run (r, buf.begin () + run, pos - run);
   return r;
 }
 
@@ -402,12 +421,10 @@ get_collection (tree& u, tree t) {
 tree
 tmu_reader::read_apply (string name, bool skip_flag) {
   // cout << "Read apply " << name << INDENT << LF;
-  tree t (make_tree_label (name));
-  if (codes->contains (name)) {
-    // cout << "  " << name << " -> " << as_string ((tree_label) codes [name])
-    // << "\n";
-    t= tree ((tree_label) codes[name]);
-  }
+  // codes 命中时免去 make_tree_label 的构造与查表(与 read 同法)
+  tree t;
+  if (codes->contains (name)) t= tree ((tree_label) codes[name]);
+  else t= tree (make_tree_label (name));
 
   bool closed= !skip_flag;
   int  buf_N = N (buf);
@@ -511,12 +528,10 @@ tmu_reader::read (bool skip_flag) {
           C << read_apply (name, false);
         }
         else {
-          tree t (make_tree_label (name));
-          if (codes->contains (name)) {
-            // cout << name << " -> " << as_string ((tree_label) codes [name])
-            // << "\n";
-            t= tree ((tree_label) codes[name]);
-          }
+          // codes 命中时免去 make_tree_label 的构造与查表
+          tree t;
+          if (codes->contains (name)) t= tree ((tree_label) codes[name]);
+          else t= tree (make_tree_label (name));
           C << t;
         }
       }
@@ -593,8 +608,9 @@ tmu_writer::cr () {
   for (i= n - 1; i >= 0; i--)
     if ((buf[i] != ' ') || ((i > 0) && (buf[i - 1] == '\\'))) break;
   if (i < n - 1) {
-    buf= buf (0, i + 1);
-    n  = n - N (buf);
+    // 原地截断代替整段前缀拷贝:buf 由 writer 独占,rep 引用计数为 1
+    buf->resize (i + 1);
+    n= n - N (buf);
     for (i= 0; i < n; i++)
       buf << "\\ ";
   }
@@ -642,23 +658,44 @@ tmu_writer::write_return () {
   ret_flag= true;
 }
 
+// 普通字符成段直写 tmp(resize + memcpy,无子串分配),
+// 转义字符单独写入——逐字符 << 与逐字符下标写都有每次调用的额外开销
+static void
+append_run (string& tmp, const char* src, int len) {
+  if (len <= 0) return;
+  int old_n= N (tmp);
+  tmp->resize (old_n + len);
+  memcpy (tmp.begin () + old_n, src, len);
+}
+
 void
 tmu_writer::write (string s, bool flag, bool encode_space) {
   if (flag) {
-    int i, n= N (s);
+    int         i, n= N (s), run= 0;
+    bool        any= false; // 是否写入了实际字符(决定 spc/ret 标志)
+    const char* raw= s.begin ();
     for (i= 0; i < n; i++) {
       char c= s[i];
-      if ((c == ' ') && (!encode_space)) write_space ();
-      else {
-        if (c == ' ') tmp << "\\ ";
-        else if (c == '\\') tmp << "\\\\";
-        else if (c == '<') tmp << "\\<";
-        else if (c == '|') tmp << "\\|";
-        else if (c == '>') tmp << "\\>";
-        else tmp << c;
-        spc_flag= false;
-        ret_flag= false;
+      if ((c == ' ') && (!encode_space)) {
+        if (i > run) any= true;
+        append_run (tmp, raw + run, i - run);
+        run= i + 1;
+        write_space ();
       }
+      else if (c == ' ' || c == '\\' || c == '<' || c == '|' || c == '>') {
+        if (i > run) any= true;
+        append_run (tmp, raw + run, i - run);
+        tmp << "\\";
+        tmp << c;
+        any= true;
+        run= i + 1;
+      }
+    }
+    if (n > run) any= true;
+    append_run (tmp, raw + run, n - run);
+    if (any) {
+      spc_flag= false;
+      ret_flag= false;
     }
   }
   else {

moebius/Data/Tree/tree_cursor.cpp

@@ -104,17 +104,8 @@ is_modified_accessible (tree t, path p, bool activate, bool persistent) {
   }
 }
 
-static bool
-next_without_border (tree t, path p) {
-  return false;
-  // Assuming that t is a concat, check whether p does not correspond
-  // to an inaccessible border position
-  int i= p->item + 1;
-  if (i >= N (t)) return false;
-  if (is_compound (t[i]) && the_drd->is_child_enforcing (t[i]))
-    return p->next == end (t[p->item]);
-  return false;
-}
+// next_without_border 已被上游禁用(恒 false 的桩),其三处调用与
+// 函数体已一并移除;原始逻辑见 git 历史与本任务 devel/moebius.md
 
 static int
 lowest_accessible_child (tree t) {
@@ -162,8 +153,8 @@ is_accessible_cursor (tree t, path p) {
     return false;
   else switch (L (t)) {
     case CONCAT:
-      if (!is_accessible_cursor (t[p->item], p->next)) return false;
-      else return !next_without_border (t, p);
+      // next_without_border 已被上游禁用(恒 false),调用移除
+      return is_accessible_cursor (t[p->item], p->next);
     case ACTIVE:
       return is_modified_accessible (t, p, true, false);
     case VAR_ACTIVE:
@@ -248,7 +239,7 @@ closest_accessible (tree t, path p, int dir) {
         path r   = closest_accessible (t[j], sp2, sdir);
         if (!is_nil (r)) {
           r= path (j, r);
-          if (!is_concat (t) || !next_without_border (t, r)) {
+          if (!is_concat (t)) {
             if (the_drd->is_parent_enforcing (t) && !graphics_in_path (t, p) &&
                 !is_accessible_cursor (t, p)) {
               if (r->item == lowest_accessible_child (t)) return path (0);
@@ -336,7 +327,7 @@ valid_cursor (tree t, path p, bool start_flag) {
         p->next == end (t[p->item]))))
     return false;
   if (is_concat (t)) {
-    if (next_without_border (t, p)) return false;
+    // next_without_border 已被上游禁用(恒 false),调用移除
     return valid_cursor (t[p->item], p->next, start_flag || (p->item != 0));
   }
   if (is_mod_active_once (t)) return is_atomic (t[0]) || (!is_atom (p->next));
@@ -492,6 +483,14 @@ right_correct (tree t, path p) {
 
 static path
 keep_positive (path p) {
+  // 常见情况全为非负索引:原样返回,免去逐层递归重建
+  bool has_neg= false;
+  for (path q= p; !is_nil (q); q= q->next)
+    if (q->item < 0) {
+      has_neg= true;
+      break;
+    }
+  if (!has_neg) return p;
   if (is_nil (p)) return p;
   if (p->item < 0) return path ();
   return path (p->item, keep_positive (p->next));
@@ -520,8 +519,12 @@ start (tree t, path p) {
 path
 end (tree t, path p) {
   // cout << "End " << p << " in " << t << "\n";
-  if ((!is_nil (p)) && (arity (parent_subtree (t, p)) == 0)) return p;
-  return correct_cursor (t, p * right_index (subtree (t, p)));
+  if (is_nil (p)) return correct_cursor (t, path (right_index (t)));
+  // 父节点已下探取得,其第 last_item(p) 个孩子即 p 所指节点,
+  // 免去 subtree 的第二次全树下探
+  tree& par= parent_subtree (t, p);
+  if (N (par) == 0) return p;
+  return correct_cursor (t, p * right_index (par[last_item (p)]));
 }
 
 path

moebius/Data/Tree/tree_modify.cpp

@@ -74,12 +74,27 @@ tree
 simplify_correct (tree t) {
   if (is_atomic (t)) return t;
   if (is_func (t, QUOTE, 1) && (is_atomic (t[0]))) return t[0];
-  int  i, n= N (t);
+  int i, n= N (t);
+  if (is_concat (t) || is_document (t)) {
+    // concat/document 需要合并/展平,维持原有重建逻辑
+    tree r (t, n);
+    for (i= 0; i < n; i++)
+      r[i]= simplify_correct (t[i]);
+    if (is_concat (r)) r= simplify_concat (r);
+    if (is_document (r)) r= simplify_document (r);
+    return r;
+  }
+  // 其他复合节点:递归结果暂存,全部孩子共享原 rep 时免去新节点分配
+  array<tree> tmp (n);
+  bool        changed= false;
+  for (i= 0; i < n; i++) {
+    tmp[i]= simplify_correct (t[i]);
+    if (!strong_equal (tmp[i], t[i])) changed= true;
+  }
+  if (!changed) return t;
   tree r (t, n);
   for (i= 0; i < n; i++)
-    r[i]= simplify_correct (t[i]);
-  if (is_concat (r)) r= simplify_concat (r);
-  if (is_document (r)) r= simplify_document (r);
+    r[i]= tmp[i];
   return r;
 }
 
@@ -127,8 +142,7 @@ correct_node (tree& t) {
   // NOTE: this routine should only modify t and its descendants,
   // but not any ancestors
   if (is_compound (t)) {
-    if (the_drd->contains (as_string (L (t))) &&
-        !the_drd->correct_arity (L (t), N (t)))
+    if (the_drd->contains (L (t)) && !the_drd->correct_arity (L (t), N (t)))
       assign (t, "");
     if (is_concat (t)) correct_concat_node (t, 0);
   }