pool_allocator.h: Qualify __throw_bad_alloc.

2004-06-18  Benjamin Kosnik  <bkoz@redhat.com>

	* include/ext/pool_allocator.h: Qualify __throw_bad_alloc.
	(__pool_base): Remove unused template parameter.  Add
	protected. Move lock data into __pool_base::_Lock. Remove static
	on member functions.
	(__pool_base::_M_get_free_list): New.
	(__pool_alloc): Move _S_force new here.
	* src/allocator.cc: Move out of line __pool_base definitions here.
	* config/linker-map.gnu: Export bits from __pool_base.

From-SVN: r83355

1 files changed, 42 insertions, 180 deletions

diff --git a/libstdc++-v3/include/ext/pool_allocator.h b/libstdc++-v3/include/ext/pool_allocator.h
index 2f0aec5..e5efac3 100644
--- a/libstdc++-v3/include/ext/pool_allocator.h
+++ b/libstdc++-v3/include/ext/pool_allocator.h
@@ -55,8 +55,6 @@
 
 namespace __gnu_cxx
 {
-  using std::__throw_bad_alloc;
-
   /**
    *  @if maint
    *  Uses various allocators to fulfill underlying requests (and makes as
@@ -71,71 +69,64 @@ namespace __gnu_cxx
    *     information that we can return the object to the proper free list
    *     without permanently losing part of the object.
    *
-   *  The template parameter specifies whether more than one thread may use
-   *  this allocator.  It is safe to allocate an object from one instance
-   *  of the allocator and deallocate it with another one.  This effectively
-   *  transfers its ownership to the second one.  This may have undesirable
-   *  effects on reference locality.
-   *
    *  @endif
    *  (See @link Allocators allocators info @endlink for more.)
    */
-  template<bool __threads>
-    struct __pool_base
+    class __pool_base
     {
+    protected:
+
       enum { _S_align = 8 };
       enum { _S_max_bytes = 128 };
-      enum { _S_freelists = _S_max_bytes / _S_align };
+      enum { _S_free_list_size = _S_max_bytes / _S_align };
       
+      // It would be nice to use _STL_auto_lock here.  But we need a
+      // test whether threads are in use.
+      struct _Lock
+      {
+	static _STL_mutex_lock        _S_lock;
+	_Lock() { _S_lock._M_acquire_lock(); }
+	~_Lock() { _S_lock._M_release_lock(); }
+      };
+
       union _Obj
       {
 	union _Obj* _M_free_list_link;
 	char        _M_client_data[1];    // The client sees this.
       };
       
-      static _Obj* volatile         _S_free_list[_S_freelists];
+      static _Obj* volatile         _S_free_list[_S_free_list_size];
       
       // Chunk allocation state.
       static char*                  _S_start_free;
       static char*                  _S_end_free;
-      static size_t                 _S_heap_size;
-      
-      static _STL_mutex_lock        _S_lock;
-      static _Atomic_word	    _S_force_new;
+      static size_t                 _S_heap_size;     
       
-      static size_t
-      _S_round_up(size_t __bytes)
+      size_t
+      _M_round_up(size_t __bytes)
       { return ((__bytes + (size_t)_S_align - 1) & ~((size_t)_S_align - 1)); }
       
-      static size_t
-      _S_freelist_index(size_t __bytes)
-      { return ((__bytes + (size_t)_S_align - 1) / (size_t)_S_align - 1); }
+      _Obj* volatile*
+      _M_get_free_list(size_t __bytes);
     
       // Returns an object of size __n, and optionally adds to size __n
       // free list.
-      static void*
-      _S_refill(size_t __n);
+      void*
+      _M_refill(size_t __n);
       
       // Allocates a chunk for nobjs of size size.  nobjs may be reduced
       // if it is inconvenient to allocate the requested number.
-      static char*
-      _S_chunk_alloc(size_t __n, int& __nobjs);
-      
-      // It would be nice to use _STL_auto_lock here.  But we need a
-      // test whether threads are in use.
-      struct _Lock
-      {
-	_Lock() { if (__threads) _S_lock._M_acquire_lock(); }
-	~_Lock() { if (__threads) _S_lock._M_release_lock(); }
-      } __attribute__ ((__unused__));
-      friend struct _Lock;
+      char*
+      _M_allocate_chunk(size_t __n, int& __nobjs);
     };
 
-  typedef __pool_base<true> __pool_alloc_base;
 
   template<typename _Tp>
-    class __pool_alloc : private __pool_alloc_base
+    class __pool_alloc : private __pool_base
     {
+    private:
+      static _Atomic_word	    _S_force_new;
+
     public:
       typedef size_t     size_type;
       typedef ptrdiff_t  difference_type;
@@ -194,116 +185,9 @@ namespace __gnu_cxx
     operator!=(const __pool_alloc<_Tp>&, const __pool_alloc<_Tp>&)
     { return false; }
 
-  // Allocate memory in large chunks in order to avoid fragmenting the
-  // heap too much.  Assume that __n is properly aligned.  We hold
-  // the allocation lock.
-  template<bool __threads>
-    char*
-    __pool_base<__threads>::_S_chunk_alloc(size_t __n, int& __nobjs)
-    {
-      char* __result;
-      size_t __total_bytes = __n * __nobjs;
-      size_t __bytes_left = _S_end_free - _S_start_free;
-      
-      if (__bytes_left >= __total_bytes)
-	{
-	  __result = _S_start_free;
-	  _S_start_free += __total_bytes;
-	  return __result ;
-	}
-      else if (__bytes_left >= __n)
-	{
-	  __nobjs = (int)(__bytes_left / __n);
-	  __total_bytes = __n * __nobjs;
-	  __result = _S_start_free;
-	  _S_start_free += __total_bytes;
-	  return __result;
-	}
-      else
-	{
-	  size_t __bytes_to_get = (2 * __total_bytes
-				   + _S_round_up(_S_heap_size >> 4));
-	  // Try to make use of the left-over piece.
-	  if (__bytes_left > 0)
-	    {
-	      _Obj* volatile* __free_list = (_S_free_list
-					     + _S_freelist_index(__bytes_left));
-	      
-	      ((_Obj*)(void*)_S_start_free)->_M_free_list_link = *__free_list;
-	      *__free_list = (_Obj*)(void*)_S_start_free;
-	    }
-	  
-	  _S_start_free = static_cast<char*>(::operator new(__bytes_to_get));
-	  if (_S_start_free == 0)
-	    {
-	      size_t __i;
-	      _Obj* volatile* __free_list;
-	      _Obj* __p;
-	      // Try to make do with what we have.  That can't hurt.  We
-	      // do not try smaller requests, since that tends to result
-	      // in disaster on multi-process machines.
-	      __i = __n;
-	      for (; __i <= (size_t) _S_max_bytes; __i += (size_t) _S_align)
-		{
-		  __free_list = _S_free_list + _S_freelist_index(__i);
-		  __p = *__free_list;
-		  if (__p != 0)
-		    {
-		      *__free_list = __p -> _M_free_list_link;
-		      _S_start_free = (char*)__p;
-		      _S_end_free = _S_start_free + __i;
-		      return _S_chunk_alloc(__n, __nobjs);
-		      // Any leftover piece will eventually make it to the
-		      // right free list.
-		    }
-		}
-	      _S_end_free = 0;        // In case of exception.
-	      _S_start_free = static_cast<char*>(::operator new(__bytes_to_get));
-	      // This should either throw an exception or remedy the situation.
-	      // Thus we assume it succeeded.
-	    }
-	  _S_heap_size += __bytes_to_get;
-	  _S_end_free = _S_start_free + __bytes_to_get;
-	  return _S_chunk_alloc(__n, __nobjs);
-	}
-    }
-  
-  // Returns an object of size __n, and optionally adds to "size
-  // __n"'s free list.  We assume that __n is properly aligned.  We
-  // hold the allocation lock.
-  template<bool __threads>
-    void*
-    __pool_base<__threads>::_S_refill(size_t __n)
-    {
-      int __nobjs = 20;
-      char* __chunk = _S_chunk_alloc(__n, __nobjs);
-      _Obj* volatile* __free_list;
-      _Obj* __result;
-      _Obj* __current_obj;
-      _Obj* __next_obj;
-      int __i;
-      
-      if (1 == __nobjs)
-	return __chunk;
-      __free_list = _S_free_list + _S_freelist_index(__n);
-      
-      // Build free list in chunk.
-      __result = (_Obj*)(void*)__chunk;
-      *__free_list = __next_obj = (_Obj*)(void*)(__chunk + __n);
-      for (__i = 1; ; __i++)
-	{
-	  __current_obj = __next_obj;
-	  __next_obj = (_Obj*)(void*)((char*)__next_obj + __n);
-	  if (__nobjs - 1 == __i)
-	    {
-	      __current_obj -> _M_free_list_link = 0;
-	      break;
-	    }
-	  else
-	    __current_obj -> _M_free_list_link = __next_obj;
-	}
-      return __result;
-    }
+  template<typename _Tp>
+    _Atomic_word
+    __pool_alloc<_Tp>::_S_force_new;
 
   template<typename _Tp>
     _Tp*
@@ -314,7 +198,6 @@ namespace __gnu_cxx
 	{
 	  if (__n <= max_size())
 	    {
-	      const size_t __bytes = __n * sizeof(_Tp);
 	      // If there is a race through here, assume answer from getenv
 	      // will resolve in same direction.  Inspired by techniques
 	      // to efficiently support threading found in basic_string.h.
@@ -325,31 +208,32 @@ namespace __gnu_cxx
 		  else
 		    __atomic_add(&_S_force_new, -1);
 		}
-	      
-	      if ((__bytes > (size_t) _S_max_bytes) || (_S_force_new > 0))
+
+	      const size_t __bytes = __n * sizeof(_Tp);	      
+	      if (__bytes > size_t(_S_max_bytes) || _S_force_new == 1)
 		__ret = static_cast<_Tp*>(::operator new(__bytes));
 	      else
 		{
-		  _Obj* volatile* __free_list = (_S_free_list
-						 + _S_freelist_index(__bytes));
+		  _Obj* volatile* __free_list = _M_get_free_list(__bytes);
+
 		  // Acquire the lock here with a constructor call.  This
 		  // ensures that it is released in exit or during stack
 		  // unwinding.
 		  _Lock __lock_instance;
 		  _Obj* __restrict__ __result = *__free_list;
 		  if (__builtin_expect(__result == 0, 0))
-		    __ret = static_cast<_Tp*>(_S_refill(_S_round_up(__bytes)));
+		    __ret = static_cast<_Tp*>(_M_refill(_M_round_up(__bytes)));
 		  else
 		    {
 		      *__free_list = __result->_M_free_list_link;
 		      __ret = reinterpret_cast<_Tp*>(__result);
 		    }
 		  if (__builtin_expect(__ret == 0, 0))
-		    __throw_bad_alloc();
+		    std::__throw_bad_alloc();
 		}
 	    }
 	  else
-	    __throw_bad_alloc();
+	    std::__throw_bad_alloc();
 	}
       return __ret;
     }
@@ -361,44 +245,22 @@ namespace __gnu_cxx
       if (__n)
 	{
 	  const size_t __bytes = __n * sizeof(_Tp);
-	  if ((__bytes > (size_t) _S_max_bytes) || (_S_force_new > 0))
+	  if (__bytes > static_cast<size_t>(_S_max_bytes) || _S_force_new == 1)
 	    ::operator delete(__p);
 	  else
 	    {
-	      _Obj* volatile* __free_list = (_S_free_list
-					     + _S_freelist_index(__bytes));
-	      _Obj* __q = (_Obj*)__p;
+	      _Obj* volatile* __free_list = _M_get_free_list(__bytes);
+	      _Obj* __q = reinterpret_cast<_Obj*>(__p);
 
 	      // Acquire the lock here with a constructor call.  This
 	      // ensures that it is released in exit or during stack
 	      // unwinding.
 	      _Lock __lock_instance;
-	      __q -> _M_free_list_link = *__free_list;
+	      __q ->_M_free_list_link = *__free_list;
 	      *__free_list = __q;
 	    }
 	}
     }
-
-  template<bool __threads>
-    typename __pool_base<__threads>::_Obj* volatile
-    __pool_base<__threads>::_S_free_list[_S_freelists];
-
-  template<bool __threads>
-    char* __pool_base<__threads>::_S_start_free = 0;
-
-  template<bool __threads>
-    char* __pool_base<__threads>::_S_end_free = 0;
-
-  template<bool __threads>
-    size_t __pool_base<__threads>::_S_heap_size = 0;
-
-  template<bool __threads>
-    _STL_mutex_lock
-    __pool_base<__threads>::_S_lock __STL_MUTEX_INITIALIZER;
-
-  template<bool __threads>
-    _Atomic_word
-    __pool_base<__threads>::_S_force_new = 0;
 } // namespace __gnu_cxx
 
 #endif