include/mimalloc-new-delete.h

/* ----------------------------------------------------------------------------
Copyright (c) 2018-2020 Microsoft Research, Daan Leijen
This is free software; you can redistribute it and/or modify it under the
terms of the MIT license. A copy of the license can be found in the file
"LICENSE" at the root of this distribution.
-----------------------------------------------------------------------------*/
#pragma once
#ifndef MIMALLOC_NEW_DELETE_H
#define MIMALLOC_NEW_DELETE_H

// -----------------------------------------------------------------------------------
// This header provides convenient overrides for the new and delete operations in C++.
//
// This header should be included in only one source file!
//
// On Windows, or when linking dynamically with mimalloc, these
// can be more performant than the standard new-delete operations.
// See <https://en.cppreference.com/w/cpp/memory/new/operator_new>
// -----------------------------------------------------------------------------------
#if defined(__cplusplus)
  #if defined(new)              // in case this is included over `mimalloc-override.h`
  #pragma push_macro("new")
  #define MI_PUSHED_NEW
  #undef new
  #endif

  #include <new>
  #include <mimalloc.h>
 
  void operator delete(void* p) noexcept              { mi_free(p); };
  void operator delete[](void* p) noexcept            { mi_free(p); };

  void* operator new(std::size_t n) noexcept(false)   { return MI_SOURCE_RET(mi_new, n); }
  void* operator new[](std::size_t n) noexcept(false) { return MI_SOURCE_RET(mi_new, n); }

  void* operator new  (std::size_t n, const std::nothrow_t& ) noexcept { return MI_SOURCE_RET(mi_new_nothrow, n); }
  void* operator new[](std::size_t n, const std::nothrow_t& ) noexcept { return MI_SOURCE_RET(mi_new_nothrow, n); }

  #if (__cplusplus >= 201402L || _MSC_VER >= 1916)
  void operator delete  (void* p, std::size_t n) noexcept { mi_free_size(p,n); };
  void operator delete[](void* p, std::size_t n) noexcept { mi_free_size(p,n); };
  #endif

  #if (__cplusplus > 201402L || defined(__cpp_aligned_new))
  void operator delete  (void* p, std::align_val_t al) noexcept { mi_free_aligned(p, static_cast<size_t>(al)); }
  void operator delete[](void* p, std::align_val_t al) noexcept { mi_free_aligned(p, static_cast<size_t>(al)); }
  void operator delete  (void* p, std::size_t n, std::align_val_t al) noexcept { mi_free_size_aligned(p, n, static_cast<size_t>(al)); };
  void operator delete[](void* p, std::size_t n, std::align_val_t al) noexcept { mi_free_size_aligned(p, n, static_cast<size_t>(al)); };

  void* operator new( std::size_t n, std::align_val_t al)   noexcept(false) { return MI_SOURCE_RET(mi_new_aligned, n, static_cast<size_t>(al)); }
  void* operator new[]( std::size_t n, std::align_val_t al) noexcept(false) { return MI_SOURCE_RET(mi_new_aligned, n, static_cast<size_t>(al)); }
  void* operator new  (std::size_t n, std::align_val_t al, const std::nothrow_t&) noexcept { return MI_SOURCE_RET(mi_new_aligned_nothrow, n, static_cast<size_t>(al)); }
  void* operator new[](std::size_t n, std::align_val_t al, const std::nothrow_t&) noexcept { return MI_SOURCE_RET(mi_new_aligned_nothrow, n, static_cast<size_t>(al)); }
  #endif

  #if !defined(NDEBUG)
  // Instances for debug override of the new operator (in `mimalloc-override.h`)
  void* operator new(std::size_t n, mi_source_t __mi_source)   noexcept(false) { (void)(__mi_source); return MI_SOURCE_ARG(mi_new, n); }
  void* operator new[](std::size_t n, mi_source_t __mi_source) noexcept(false) { (void)(__mi_source); return MI_SOURCE_ARG(mi_new, n); }

  void operator delete(void* p, mi_source_t )   noexcept { mi_free(p); };
  void operator delete[](void* p, mi_source_t ) noexcept { mi_free(p); };
  #endif

  #if defined(MI_PUSHED_NEW)
  #pragma pop_macro("new")
  #endif
#endif

#endif // MIMALLOC_NEW_DELETE_H