basic_string.tcc (_M_mutate): Do not reallocate unnecessarily when _M_rep() ==…

basic_string.tcc (_M_mutate): Do not reallocate unnecessarily when _M_rep() == &_S_empty_rep() and __new_size...

2004-10-18  Paolo Carlini  <pcarlini@suse.de>

	* include/bits/basic_string.tcc (_M_mutate): Do not reallocate
	unnecessarily when _M_rep() == &_S_empty_rep() and __new_size
	== capacity() (== 0): is ok to just leave everything unchanged.

	* include/bits/basic_string.h: Minor formatting fixes.
	* include/bits/basic_string.tcc: Likewise.

From-SVN: r89199

libstdc++-v3/ChangeLog

+2004-10-18  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/bits/basic_string.tcc (_M_mutate): Do not reallocate
+	unnecessarily when _M_rep() == &_S_empty_rep() and __new_size
+	== capacity() (== 0): is ok to just leave everything unchanged.
+
+	* include/bits/basic_string.h: Minor formatting fixes.
+	* include/bits/basic_string.tcc: Likewise.
+
 2004-10-17  Benjamin Kosnik  <bkoz@redhat.com>
 
 	* include/ext/mt_allocator.h (__pool::_M_get_align): New.

libstdc++-v3/include/bits/basic_string.h

@@ -271,10 +271,12 @@ namespace std
       // For the internal use we have functions similar to `begin'/`end'
       // but they do not call _M_leak.
       iterator
-      _M_ibegin() const { return iterator(_M_data()); }
+      _M_ibegin() const
+      { return iterator(_M_data()); }
 
       iterator
-      _M_iend() const { return iterator(_M_data() + this->size()); }
+      _M_iend() const
+      { return iterator(_M_data() + this->size()); }
 
       void
       _M_leak()    // for use in begin() & non-const op[]
@@ -527,16 +529,19 @@ namespace std
       ///  Returns the number of characters in the string, not including any
       ///  null-termination.
       size_type
-      size() const { return _M_rep()->_M_length; }
+      size() const
+      { return _M_rep()->_M_length; }
 
       ///  Returns the number of characters in the string, not including any
       ///  null-termination.
       size_type
-      length() const { return _M_rep()->_M_length; }
+      length() const
+      { return _M_rep()->_M_length; }
 
       /// Returns the size() of the largest possible %string.
       size_type
-      max_size() const { return _Rep::_S_max_size; }
+      max_size() const
+      { return _Rep::_S_max_size; }
 
       /**
        *  @brief  Resizes the %string to the specified number of characters.
@@ -562,14 +567,16 @@ namespace std
        *  setting them to 0.
        */
       void
-      resize(size_type __n) { this->resize(__n, _CharT()); }
+      resize(size_type __n)
+      { this->resize(__n, _CharT()); }
 
       /**
        *  Returns the total number of characters that the %string can hold
        *  before needing to allocate more memory.
        */
       size_type
-      capacity() const { return _M_rep()->_M_capacity; }
+      capacity() const
+      { return _M_rep()->_M_capacity; }
 
       /**
        *  @brief  Attempt to preallocate enough memory for specified number of
@@ -595,13 +602,15 @@ namespace std
        *  Erases the string, making it empty.
        */
       void
-      clear() { _M_mutate(0, this->size(), 0); }
+      clear()
+      { _M_mutate(0, this->size(), 0); }
 
       /**
        *  Returns true if the %string is empty.  Equivalent to *this == "".
        */
       bool
-      empty() const { return this->size() == 0; }
+      empty() const
+      { return this->size() == 0; }
 
       // Element access:
       /**
@@ -684,7 +693,8 @@ namespace std
        *  @return  Reference to this string.
        */
       basic_string&
-      operator+=(const basic_string& __str) { return this->append(__str); }
+      operator+=(const basic_string& __str)
+      { return this->append(__str); }
 
       /**
        *  @brief  Append a C string.
@@ -692,7 +702,8 @@ namespace std
        *  @return  Reference to this string.
        */
       basic_string&
-      operator+=(const _CharT* __s) { return this->append(__s); }
+      operator+=(const _CharT* __s)
+      { return this->append(__s); }
 
       /**
        *  @brief  Append a character.
@@ -700,7 +711,8 @@ namespace std
        *  @return  Reference to this string.
        */
       basic_string&
-      operator+=(_CharT __c) { return this->append(size_type(1), __c); }
+      operator+=(_CharT __c)
+      { return this->append(size_type(1), __c); }
 
       /**
        *  @brief  Append a string to this string.
@@ -1447,7 +1459,8 @@ namespace std
        *  happen.
       */
       const _CharT*
-      c_str() const { return _M_data(); }
+      c_str() const
+      { return _M_data(); }
 
       /**
        *  @brief  Return const pointer to contents.
@@ -1456,13 +1469,15 @@ namespace std
        *  happen.
       */
       const _CharT*
-      data() const { return _M_data(); }
+      data() const
+      { return _M_data(); }
 
       /**
        *  @brief  Return copy of allocator used to construct this string.
       */
       allocator_type
-      get_allocator() const { return _M_dataplus; }
+      get_allocator() const
+      { return _M_dataplus; }
 
       /**
        *  @brief  Find position of a C substring.

libstdc++-v3/include/bits/basic_string.tcc

@@ -373,7 +373,8 @@ namespace std
 
   template<typename _CharT, typename _Traits, typename _Alloc>
     void
-    basic_string<_CharT, _Traits, _Alloc>::_M_leak_hard()
+    basic_string<_CharT, _Traits, _Alloc>::
+    _M_leak_hard()
     {
 #ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
       if (_M_rep() == &_S_empty_rep())
@@ -393,16 +394,11 @@ namespace std
       const size_type __new_size = __old_size + __len2 - __len1;
       const size_type __how_much = __old_size - __pos - __len1;
 
-#ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
-      if (_M_rep() == &_S_empty_rep()
-	  || _M_rep()->_M_is_shared() || __new_size > capacity())
-#else
-      if (_M_rep()->_M_is_shared() || __new_size > capacity())
-#endif
+      if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
 	{
 	  // Must reallocate.
 	  const allocator_type __a = get_allocator();
-	  _Rep* __r = _Rep::_S_create(__new_size, capacity(), __a);
+	  _Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
 
 	  if (__pos)
 	    traits_type::copy(__r->_M_refdata(), _M_data(), __pos);
@@ -427,7 +423,8 @@ namespace std
 
   template<typename _CharT, typename _Traits, typename _Alloc>
     void
-    basic_string<_CharT, _Traits, _Alloc>::reserve(size_type __res)
+    basic_string<_CharT, _Traits, _Alloc>::
+    reserve(size_type __res)
     {
       if (__res != this->capacity() || _M_rep()->_M_is_shared())
         {
@@ -444,7 +441,9 @@ namespace std
     }
 
   template<typename _CharT, typename _Traits, typename _Alloc>
-    void basic_string<_CharT, _Traits, _Alloc>::swap(basic_string& __s)
+    void
+    basic_string<_CharT, _Traits, _Alloc>::
+    swap(basic_string& __s)
     {
       if (_M_rep()->_M_is_leaked())
 	_M_rep()->_M_set_sharable();
@@ -561,7 +560,8 @@ namespace std
 
   template<typename _CharT, typename _Traits, typename _Alloc>
     void
-    basic_string<_CharT, _Traits, _Alloc>::resize(size_type __n, _CharT __c)
+    basic_string<_CharT, _Traits, _Alloc>::
+    resize(size_type __n, _CharT __c)
     {
       if (__n > max_size())
 	__throw_length_error(__N("basic_string::resize"));