81 lines
2.3 KiB
C++
81 lines
2.3 KiB
C++
/* This file is part of the dynarmic project.
|
|
* Copyright (c) 2016 MerryMage
|
|
* This software may be used and distributed according to the terms of the GNU
|
|
* General Public License version 2 or any later version.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <bitset>
|
|
#include <climits>
|
|
#include <cstddef>
|
|
|
|
#include "common/assert.h"
|
|
|
|
#ifdef _MSC_VER
|
|
#include <intrin.h>
|
|
#endif
|
|
|
|
namespace Dynarmic {
|
|
namespace Common {
|
|
|
|
/// The size of a type in terms of bits
|
|
template<typename T>
|
|
constexpr size_t BitSize() {
|
|
return sizeof(T) * CHAR_BIT;
|
|
}
|
|
|
|
/// Extract bits [begin_bit, end_bit] inclusive from value of type T.
|
|
template<size_t begin_bit, size_t end_bit, typename T>
|
|
constexpr T Bits(const T value) {
|
|
static_assert(begin_bit < end_bit,
|
|
"invalid bit range (position of beginning bit cannot be greater than that of end bit)");
|
|
static_assert(begin_bit < BitSize<T>(), "begin_bit must be smaller than size of T");
|
|
static_assert(end_bit < BitSize<T>(), "begin_bit must be smaller than size of T");
|
|
|
|
return (value >> begin_bit) & ((1 << (end_bit - begin_bit + 1)) - 1);
|
|
}
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma warning(push)
|
|
#pragma warning(disable:4554)
|
|
#endif
|
|
/// Extracts a single bit at bit_position from value of type T.
|
|
template<size_t bit_position, typename T>
|
|
constexpr bool Bit(const T value) {
|
|
static_assert(bit_position < BitSize<T>(), "bit_position must be smaller than size of T");
|
|
|
|
return ((value >> bit_position) & 1) != 0;
|
|
}
|
|
|
|
/// Extracts a single bit at bit_position from value of type T.
|
|
template<typename T>
|
|
constexpr bool Bit(size_t bit_position, const T value) {
|
|
ASSERT_MSG(bit_position < BitSize<T>(), "bit_position must be smaller than size of T");
|
|
|
|
return ((value >> bit_position) & 1) != 0;
|
|
}
|
|
#ifdef _MSC_VER
|
|
#pragma warning(pop)
|
|
#endif
|
|
|
|
/// Sign-extends a value that has NBits bits to the full bitwidth of type T.
|
|
template<size_t bit_count, typename T>
|
|
inline T SignExtend(const T value) {
|
|
static_assert(bit_count <= BitSize<T>(), "bit_count larger than bitsize of T");
|
|
|
|
constexpr T mask = static_cast<T>(1ULL << bit_count) - 1;
|
|
const bool signbit = Bit<bit_count - 1, T>(value);
|
|
if (signbit) {
|
|
return value | ~mask;
|
|
}
|
|
return value;
|
|
}
|
|
|
|
template <typename Integral>
|
|
inline size_t BitCount(Integral value) {
|
|
return std::bitset<BitSize<Integral>()>(value).count();
|
|
}
|
|
|
|
} // namespace Common
|
|
} // namespace Dynarmic
|