82 строки
2.2 KiB
C++
82 строки
2.2 KiB
C++
//--------------------------------------------------------------------------------------
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// File: AlignedNew.h
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//
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// Copyright (c) Microsoft Corporation.
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// Licensed under the MIT License.
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//
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// http://go.microsoft.com/fwlink/?LinkId=248929
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// http://go.microsoft.com/fwlink/?LinkID=615561
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//--------------------------------------------------------------------------------------
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#pragma once
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#include <cstddef>
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#include <cstdlib>
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#include <new>
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#ifdef _WIN32
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#include <malloc.h>
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#endif
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namespace DirectX
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{
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// Derive from this to customize operator new and delete for
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// types that have special heap alignment requirements.
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//
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// Example usage:
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//
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// XM_ALIGNED_STRUCT(16) MyAlignedType : public AlignedNew<MyAlignedType>
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template<typename TDerived>
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struct AlignedNew
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{
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// Allocate aligned memory.
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static void* operator new (size_t size)
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{
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const size_t alignment = alignof(TDerived);
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static_assert(alignment > 8, "AlignedNew is only useful for types with > 8 byte alignment. Did you forget a __declspec(align) on TDerived?");
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static_assert(((alignment - 1) & alignment) == 0, "AlignedNew only works with power of two alignment");
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#ifdef _WIN32
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void* ptr = _aligned_malloc(size, alignment);
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#else
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// This C++17 Standard Library function is currently NOT
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// implemented for the Microsoft Standard C++ Library.
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void* ptr = aligned_alloc(alignment, size);
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#endif
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if (!ptr)
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throw std::bad_alloc();
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return ptr;
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}
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// Free aligned memory.
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static void operator delete (void* ptr)
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{
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#ifdef _WIN32
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_aligned_free(ptr);
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#else
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free(ptr);
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#endif
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}
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// Array overloads.
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static void* operator new[](size_t size)
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{
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static_assert((sizeof(TDerived) % alignof(TDerived) == 0), "AlignedNew expects type to be padded to the alignment");
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return operator new(size);
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}
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static void operator delete[](void* ptr)
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{
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operator delete(ptr);
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}
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};
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}
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