1 // Copyright 2017 Dolphin Emulator Project
2 // Licensed under GPLv2+
3 // Refer to the license.txt file included.
4
5 #include <gtest/gtest.h>
6
7 #include "Common/BitUtils.h"
8 #include "Common/CommonTypes.h"
9
TEST(BitUtils,BitSize)10 TEST(BitUtils, BitSize)
11 {
12 EXPECT_EQ(Common::BitSize<s8>(), 8u);
13 EXPECT_EQ(Common::BitSize<s16>(), 16u);
14 EXPECT_EQ(Common::BitSize<s32>(), 32u);
15 EXPECT_EQ(Common::BitSize<s64>(), 64u);
16
17 EXPECT_EQ(Common::BitSize<u8>(), 8u);
18 EXPECT_EQ(Common::BitSize<u16>(), 16u);
19 EXPECT_EQ(Common::BitSize<u32>(), 32u);
20 EXPECT_EQ(Common::BitSize<u64>(), 64u);
21 }
22
TEST(BitUtils,ExtractBit)23 TEST(BitUtils, ExtractBit)
24 {
25 constexpr s32 zero = 0;
26 EXPECT_EQ(Common::ExtractBit<0>(zero), 0);
27
28 constexpr s32 one = 1;
29 EXPECT_EQ(Common::ExtractBit<0>(one), 1);
30
31 constexpr s32 negative_one = -1;
32 EXPECT_EQ(Common::ExtractBit<31>(negative_one), 1);
33
34 constexpr s32 one_hundred_twenty_eight = 0b10000000;
35 EXPECT_EQ(Common::ExtractBit<7>(one_hundred_twenty_eight), 1);
36 }
37
TEST(BitUtils,ExtractBits)38 TEST(BitUtils, ExtractBits)
39 {
40 // Note: Parenthesizing is necessary to prevent the macros from
41 // mangling the template function usages.
42
43 constexpr s32 two_hundred_four_signed = 0b0011001100;
44 EXPECT_EQ((Common::ExtractBits<2, 3>(two_hundred_four_signed)), 3u);
45 EXPECT_EQ((Common::ExtractBits<2, 7>(two_hundred_four_signed)), 51u);
46 EXPECT_EQ((Common::ExtractBits<3, 6>(two_hundred_four_signed)), 9u);
47
48 constexpr u32 two_hundred_four_unsigned = 0b0011001100;
49 EXPECT_EQ((Common::ExtractBits<2, 3>(two_hundred_four_unsigned)), 3u);
50 EXPECT_EQ((Common::ExtractBits<2, 7>(two_hundred_four_unsigned)), 51u);
51 EXPECT_EQ((Common::ExtractBits<3, 6>(two_hundred_four_unsigned)), 9u);
52
53 // Ensure bit extraction remains sign-independent even when signed types are used.
54 constexpr s32 negative_one = -1;
55 EXPECT_EQ((Common::ExtractBits<0, 31>(negative_one)), 0xFFFFFFFFU);
56
57 // Ensure bit extraction with type overriding works as expected
58 EXPECT_EQ((Common::ExtractBits<0, 31, s32, s32>(negative_one)), -1);
59 }
60
TEST(BitUtils,RotateLeft)61 TEST(BitUtils, RotateLeft)
62 {
63 EXPECT_EQ(Common::RotateLeft(0xF0F0F0F0, 0), 0xF0F0F0F0U);
64 EXPECT_EQ(Common::RotateLeft(0xF0F0F0F0, 4), 0x0F0F0F0FU);
65 EXPECT_EQ(Common::RotateLeft(0xF0F0F0F0, 8), 0xF0F0F0F0U);
66 EXPECT_EQ(Common::RotateLeft(0xF0F0F0F0F0F0F0F0, 0), 0xF0F0F0F0F0F0F0F0U);
67 EXPECT_EQ(Common::RotateLeft(0xF0F0F0F0F0F0F0F0, 4), 0x0F0F0F0F0F0F0F0FU);
68 EXPECT_EQ(Common::RotateLeft(0xF0F0F0F0F0F0F0F0, 8), 0xF0F0F0F0F0F0F0F0U);
69
70 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1, 1), 0xE3E3E3E3U);
71 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1, 2), 0xC7C7C7C7U);
72 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1, 3), 0x8F8F8F8FU);
73 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1, 4), 0x1F1F1F1FU);
74 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1F1F1F1F1, 1), 0xE3E3E3E3E3E3E3E3U);
75 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1F1F1F1F1, 2), 0xC7C7C7C7C7C7C7C7U);
76 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1F1F1F1F1, 3), 0x8F8F8F8F8F8F8F8FU);
77 EXPECT_EQ(Common::RotateLeft(0xF1F1F1F1F1F1F1F1, 4), 0x1F1F1F1F1F1F1F1FU);
78 }
79
TEST(BitUtils,RotateRight)80 TEST(BitUtils, RotateRight)
81 {
82 EXPECT_EQ(Common::RotateRight(0xF0F0F0F0, 0), 0xF0F0F0F0U);
83 EXPECT_EQ(Common::RotateRight(0xF0F0F0F0, 4), 0x0F0F0F0FU);
84 EXPECT_EQ(Common::RotateRight(0xF0F0F0F0, 8), 0xF0F0F0F0U);
85 EXPECT_EQ(Common::RotateRight(0xF0F0F0F0F0F0F0F0, 0), 0xF0F0F0F0F0F0F0F0U);
86 EXPECT_EQ(Common::RotateRight(0xF0F0F0F0F0F0F0F0, 4), 0x0F0F0F0F0F0F0F0FU);
87 EXPECT_EQ(Common::RotateRight(0xF0F0F0F0F0F0F0F0, 8), 0xF0F0F0F0F0F0F0F0U);
88
89 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1, 1), 0xF8F8F8F8U);
90 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1, 2), 0x7C7C7C7CU);
91 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1, 3), 0x3E3E3E3EU);
92 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1, 4), 0x1F1F1F1FU);
93 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1F1F1F1F1, 1), 0xF8F8F8F8F8F8F8F8U);
94 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1F1F1F1F1, 2), 0x7C7C7C7C7C7C7C7CU);
95 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1F1F1F1F1, 3), 0x3E3E3E3E3E3E3E3EU);
96 EXPECT_EQ(Common::RotateRight(0xF1F1F1F1F1F1F1F1, 4), 0x1F1F1F1F1F1F1F1FU);
97 }
98
TEST(BitUtils,IsValidLowMask)99 TEST(BitUtils, IsValidLowMask)
100 {
101 EXPECT_TRUE(Common::IsValidLowMask(0b0u));
102 EXPECT_TRUE(Common::IsValidLowMask(0b1u));
103 EXPECT_FALSE(Common::IsValidLowMask(0b10u));
104 EXPECT_TRUE(Common::IsValidLowMask(0b11u));
105 EXPECT_FALSE(Common::IsValidLowMask(0b1110u));
106 EXPECT_TRUE(Common::IsValidLowMask(0b1111u));
107 EXPECT_FALSE(Common::IsValidLowMask(0b10000u));
108 EXPECT_FALSE(Common::IsValidLowMask(0b101111u));
109
110 EXPECT_TRUE(Common::IsValidLowMask((u8)~0b0));
111 EXPECT_FALSE(Common::IsValidLowMask((u8)(~0b0 - 1)));
112 EXPECT_FALSE(Common::IsValidLowMask((u8) ~(0b10000)));
113 EXPECT_FALSE(Common::IsValidLowMask((u8)(~((u8)(~0b0) >> 1) | 0b1111)));
114
115 EXPECT_TRUE(Common::IsValidLowMask((u16)~0b0));
116 EXPECT_FALSE(Common::IsValidLowMask((u16)(~0b0 - 1)));
117 EXPECT_FALSE(Common::IsValidLowMask((u16) ~(0b10000)));
118 EXPECT_FALSE(Common::IsValidLowMask((u16)(~((u16)(~0b0) >> 1) | 0b1111)));
119
120 EXPECT_TRUE(Common::IsValidLowMask((u32)~0b0));
121 EXPECT_FALSE(Common::IsValidLowMask((u32)(~0b0 - 1)));
122 EXPECT_FALSE(Common::IsValidLowMask((u32) ~(0b10000)));
123 EXPECT_FALSE(Common::IsValidLowMask((u32)(~((u32)(~0b0) >> 1) | 0b1111)));
124
125 EXPECT_TRUE(Common::IsValidLowMask((u64)~0b0));
126 EXPECT_FALSE(Common::IsValidLowMask((u64)(~0b0 - 1)));
127 EXPECT_FALSE(Common::IsValidLowMask((u64) ~(0b10000)));
128 EXPECT_FALSE(Common::IsValidLowMask((u64)(~((u64)(~0b0) >> 1) | 0b1111)));
129 }
130
TEST(BitUtils,BitCast)131 TEST(BitUtils, BitCast)
132 {
133 EXPECT_EQ(0x00000000U, Common::BitCast<u32>(0.0f));
134 EXPECT_EQ(0x80000000U, Common::BitCast<u32>(-0.0f));
135 EXPECT_EQ(0x3F800000U, Common::BitCast<u32>(1.0f));
136 EXPECT_EQ(0xBF800000U, Common::BitCast<u32>(-1.0f));
137
138 EXPECT_EQ(0x0000000000000000ULL, Common::BitCast<u64>(0.0));
139 EXPECT_EQ(0x8000000000000000ULL, Common::BitCast<u64>(-0.0));
140 EXPECT_EQ(0x3FF0000000000000ULL, Common::BitCast<u64>(1.0));
141 EXPECT_EQ(0xBFF0000000000000ULL, Common::BitCast<u64>(-1.0));
142 }
143