dynarmic/src/common/cast_util.h
2020-04-23 15:45:57 +01:00

45 lines
1.7 KiB
C++

/* This file is part of the dynarmic project.
* Copyright (c) 2018 MerryMage
* SPDX-License-Identifier: 0BSD
*/
#pragma once
#include <cstring>
#include <type_traits>
#include <mp/traits/function_info.h>
namespace Dynarmic::Common {
/// Reinterpret objects of one type as another by bit-casting between object representations.
template <class Dest, class Source>
inline Dest BitCast(const Source& source) noexcept {
static_assert(sizeof(Dest) == sizeof(Source), "size of destination and source objects must be equal");
static_assert(std::is_trivially_copyable_v<Dest>, "destination type must be trivially copyable.");
static_assert(std::is_trivially_copyable_v<Source>, "source type must be trivially copyable");
std::aligned_storage_t<sizeof(Dest), alignof(Dest)> dest;
std::memcpy(&dest, &source, sizeof(dest));
return reinterpret_cast<Dest&>(dest);
}
/// Reinterpret objects of any arbitrary type as another type by bit-casting between object representations.
/// Note that here we do not verify if source has enough bytes to read from.
template <class Dest, class SourcePtr>
inline Dest BitCastPointee(const SourcePtr source) noexcept {
static_assert(sizeof(SourcePtr) == sizeof(void*), "source pointer must have size of a pointer");
static_assert(std::is_trivially_copyable_v<Dest>, "destination type must be trivially copyable.");
std::aligned_storage_t<sizeof(Dest), alignof(Dest)> dest;
std::memcpy(&dest, BitCast<void*>(source), sizeof(dest));
return reinterpret_cast<Dest&>(dest);
}
/// Cast a lambda into an equivalent function pointer.
template <class Function>
inline auto FptrCast(Function f) noexcept {
return static_cast<mp::equivalent_function_type<Function>*>(f);
}
} // namespace Dynarmic::Common