mirror of git://gcc.gnu.org/git/gcc.git
				
				
				
			
		
			
				
	
	
		
			154 lines
		
	
	
		
			4.6 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			154 lines
		
	
	
		
			4.6 KiB
		
	
	
	
		
			C++
		
	
	
	
// <memory> -*- C++ -*-
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// Copyright (C) 2001-2016 Free Software Foundation, Inc.
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//
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// This file is part of the GNU ISO C++ Library.  This library is free
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// software; you can redistribute it and/or modify it under the
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// terms of the GNU General Public License as published by the
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// Free Software Foundation; either version 3, or (at your option)
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// any later version.
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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// GNU General Public License for more details.
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// Under Section 7 of GPL version 3, you are granted additional
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// permissions described in the GCC Runtime Library Exception, version
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// 3.1, as published by the Free Software Foundation.
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// You should have received a copy of the GNU General Public License and
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// a copy of the GCC Runtime Library Exception along with this program;
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// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
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// <http://www.gnu.org/licenses/>.
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/*
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 * Copyright (c) 1997-1999
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 * Silicon Graphics Computer Systems, Inc.
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 *
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 * Permission to use, copy, modify, distribute and sell this software
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 * and its documentation for any purpose is hereby granted without fee,
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 * provided that the above copyright notice appear in all copies and
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 * that both that copyright notice and this permission notice appear
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 * in supporting documentation.  Silicon Graphics makes no
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 * representations about the suitability of this software for any
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 * purpose.  It is provided "as is" without express or implied warranty.
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 *
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 */
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/** @file include/memory
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 *  This is a Standard C++ Library header.
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 */
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#ifndef _GLIBCXX_MEMORY
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#define _GLIBCXX_MEMORY 1
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#pragma GCC system_header
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/**
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 * @defgroup memory Memory
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 * @ingroup utilities
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 *
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 * Components for memory allocation, deallocation, and management.
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 */
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/**
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 * @defgroup pointer_abstractions Pointer Abstractions
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 * @ingroup memory
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 *
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 * Smart pointers, etc.
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 */
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#include <bits/stl_algobase.h>
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#include <bits/allocator.h>
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#include <bits/stl_construct.h>
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#include <bits/stl_uninitialized.h>
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#include <bits/stl_tempbuf.h>
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#include <bits/stl_raw_storage_iter.h>
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#if __cplusplus >= 201103L
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#  include <exception>        	  // std::exception
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#  include <typeinfo>         	  // std::type_info in get_deleter
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#  include <iosfwd>           	  // std::basic_ostream
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#  include <ext/atomicity.h>
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#  include <ext/concurrence.h>
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#  include <bits/functexcept.h>
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#  include <bits/stl_function.h>  // std::less
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#  include <bits/uses_allocator.h>
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#  include <type_traits>
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#  include <debug/debug.h>
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#  include <bits/unique_ptr.h>
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#  include <bits/shared_ptr.h>
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#  include <bits/shared_ptr_atomic.h>
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#  if _GLIBCXX_USE_DEPRECATED
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#    include <backward/auto_ptr.h>
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#  endif
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#else
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#  include <backward/auto_ptr.h>
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#endif
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#if __cplusplus >= 201103L
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#  include <cstdint>
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#  ifdef _GLIBCXX_USE_C99_STDINT_TR1
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namespace std _GLIBCXX_VISIBILITY(default)
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{
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_GLIBCXX_BEGIN_NAMESPACE_VERSION
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/**
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 *  @brief Fit aligned storage in buffer.
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 *
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 *  [ptr.align]
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 *
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 *  This function tries to fit @a __size bytes of storage with alignment
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 *  @a __align into the buffer @a __ptr of size @a __space bytes.  If such
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 *  a buffer fits then @a __ptr is changed to point to the first byte of the
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 *  aligned storage and @a __space is reduced by the bytes used for alignment.
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 *
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 *  @param __align   A fundamental or extended alignment value.
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 *  @param __size    Size of the aligned storage required.
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 *  @param __ptr     Pointer to a buffer of @a __space bytes.
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 *  @param __space   Size of the buffer pointed to by @a __ptr.
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 *  @return the updated pointer if the aligned storage fits, otherwise nullptr.
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 */
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inline void*
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align(size_t __align, size_t __size, void*& __ptr, size_t& __space) noexcept
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{
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  const auto __intptr = reinterpret_cast<uintptr_t>(__ptr);
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  const auto __aligned = (__intptr - 1u + __align) & -__align;
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  const auto __diff = __aligned - __intptr;
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  if ((__size + __diff) > __space)
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    return nullptr;
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  else
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    {
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      __space -= __diff;
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      return __ptr = reinterpret_cast<void*>(__aligned);
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    }
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}
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// 20.7.4 [util.dynamic.safety], pointer safety
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enum class pointer_safety { relaxed, preferred, strict };
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inline void
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declare_reachable(void*) { }
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template <class T>
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  inline T*
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  undeclare_reachable(T* __p) { return __p; }
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inline void
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declare_no_pointers(char*, size_t) { }
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inline void
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undeclare_no_pointers(char*, size_t) { }
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inline pointer_safety
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get_pointer_safety() noexcept { return pointer_safety::relaxed; }
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_GLIBCXX_END_NAMESPACE_VERSION
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} // namespace
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#endif // _GLIBCXX_USE_C99_STDINT_TR1
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#endif // C++11
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#endif /* _GLIBCXX_MEMORY */
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