yuzu/src/tests/common/bit_field.cpp

91 lines
2.9 KiB
C++
Raw Normal View History

// Copyright 2019 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <array>
#include <cstring>
#include <type_traits>
#include <catch2/catch.hpp>
#include "common/bit_field.h"
TEST_CASE("BitField", "[common]") {
enum class TestEnum : u32 {
A = 0b10111101,
B = 0b10101110,
C = 0b00001111,
};
union LEBitField {
u32_le raw;
BitField<0, 6, u32> a;
BitField<6, 4, s32> b;
BitField<10, 8, TestEnum> c;
BitField<18, 14, u32> d;
} le_bitfield;
union BEBitField {
u32_be raw;
BitFieldBE<0, 6, u32> a;
BitFieldBE<6, 4, s32> b;
BitFieldBE<10, 8, TestEnum> c;
BitFieldBE<18, 14, u32> d;
} be_bitfield;
static_assert(sizeof(LEBitField) == sizeof(u32));
static_assert(sizeof(BEBitField) == sizeof(u32));
static_assert(std::is_trivially_copyable_v<LEBitField>);
static_assert(std::is_trivially_copyable_v<BEBitField>);
std::array<u8, 4> raw{{
0b01101100,
0b11110110,
0b10111010,
0b11101100,
}};
std::memcpy(&le_bitfield, &raw, sizeof(raw));
std::memcpy(&be_bitfield, &raw, sizeof(raw));
// bit fields: 11101100101110'10111101'1001'101100
REQUIRE(le_bitfield.raw == 0b11101100'10111010'11110110'01101100);
REQUIRE(le_bitfield.a == 0b101100);
REQUIRE(le_bitfield.b == -7); // 1001 as two's complement
REQUIRE(le_bitfield.c == TestEnum::A);
REQUIRE(le_bitfield.d == 0b11101100101110);
le_bitfield.a.Assign(0b000111);
le_bitfield.b.Assign(-1);
le_bitfield.c.Assign(TestEnum::C);
le_bitfield.d.Assign(0b01010101010101);
std::memcpy(&raw, &le_bitfield, sizeof(raw));
// bit fields: 01010101010101'00001111'1111'000111
REQUIRE(le_bitfield.raw == 0b01010101'01010100'00111111'11000111);
REQUIRE(raw == std::array<u8, 4>{{
0b11000111,
0b00111111,
0b01010100,
0b01010101,
}});
// bit fields: 01101100111101'10101110'1011'101100
REQUIRE(be_bitfield.raw == 0b01101100'11110110'10111010'11101100);
REQUIRE(be_bitfield.a == 0b101100);
REQUIRE(be_bitfield.b == -5); // 1011 as two's complement
REQUIRE(be_bitfield.c == TestEnum::B);
REQUIRE(be_bitfield.d == 0b01101100111101);
be_bitfield.a.Assign(0b000111);
be_bitfield.b.Assign(-1);
be_bitfield.c.Assign(TestEnum::C);
be_bitfield.d.Assign(0b01010101010101);
std::memcpy(&raw, &be_bitfield, sizeof(raw));
// bit fields: 01010101010101'00001111'1111'000111
REQUIRE(be_bitfield.raw == 0b01010101'01010100'00111111'11000111);
REQUIRE(raw == std::array<u8, 4>{{
0b01010101,
0b01010100,
0b00111111,
0b11000111,
}});
}