1 // Copyright 2006-2008 the V8 project authors. All rights reserved.
2
3 #include <stdlib.h>
4
5 #include "v8.h"
6
7 #include "platform.h"
8 #include "cctest.h"
9 #include "diy-fp.h"
10 #include "double.h"
11
12
13 using namespace v8::internal;
14
15
TEST(Uint64Conversions)16 TEST(Uint64Conversions) {
17 // Start by checking the byte-order.
18 uint64_t ordered = V8_2PART_UINT64_C(0x01234567, 89ABCDEF);
19 CHECK_EQ(3512700564088504e-318, Double(ordered).value());
20
21 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
22 CHECK_EQ(5e-324, Double(min_double64).value());
23
24 uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff);
25 CHECK_EQ(1.7976931348623157e308, Double(max_double64).value());
26 }
27
TEST(AsDiyFp)28 TEST(AsDiyFp) {
29 uint64_t ordered = V8_2PART_UINT64_C(0x01234567, 89ABCDEF);
30 DiyFp diy_fp = Double(ordered).AsDiyFp();
31 CHECK_EQ(0x12 - 0x3FF - 52, diy_fp.e());
32 // The 52 mantissa bits, plus the implicit 1 in bit 52 as a UINT64.
33 CHECK(V8_2PART_UINT64_C(0x00134567, 89ABCDEF) == diy_fp.f()); // NOLINT
34
35 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
36 diy_fp = Double(min_double64).AsDiyFp();
37 CHECK_EQ(-0x3FF - 52 + 1, diy_fp.e());
38 // This is a denormal; so no hidden bit.
39 CHECK(1 == diy_fp.f()); // NOLINT
40
41 uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff);
42 diy_fp = Double(max_double64).AsDiyFp();
43 CHECK_EQ(0x7FE - 0x3FF - 52, diy_fp.e());
44 CHECK(V8_2PART_UINT64_C(0x001fffff, ffffffff) == diy_fp.f()); // NOLINT
45 }
46
47
TEST(AsNormalizedDiyFp)48 TEST(AsNormalizedDiyFp) {
49 uint64_t ordered = V8_2PART_UINT64_C(0x01234567, 89ABCDEF);
50 DiyFp diy_fp = Double(ordered).AsNormalizedDiyFp();
51 CHECK_EQ(0x12 - 0x3FF - 52 - 11, diy_fp.e());
52 CHECK((V8_2PART_UINT64_C(0x00134567, 89ABCDEF) << 11) ==
53 diy_fp.f()); // NOLINT
54
55 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
56 diy_fp = Double(min_double64).AsNormalizedDiyFp();
57 CHECK_EQ(-0x3FF - 52 + 1 - 63, diy_fp.e());
58 // This is a denormal; so no hidden bit.
59 CHECK(V8_2PART_UINT64_C(0x80000000, 00000000) == diy_fp.f()); // NOLINT
60
61 uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff);
62 diy_fp = Double(max_double64).AsNormalizedDiyFp();
63 CHECK_EQ(0x7FE - 0x3FF - 52 - 11, diy_fp.e());
64 CHECK((V8_2PART_UINT64_C(0x001fffff, ffffffff) << 11) ==
65 diy_fp.f()); // NOLINT
66 }
67
68
TEST(IsDenormal)69 TEST(IsDenormal) {
70 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
71 CHECK(Double(min_double64).IsDenormal());
72 uint64_t bits = V8_2PART_UINT64_C(0x000FFFFF, FFFFFFFF);
73 CHECK(Double(bits).IsDenormal());
74 bits = V8_2PART_UINT64_C(0x00100000, 00000000);
75 CHECK(!Double(bits).IsDenormal());
76 }
77
78
TEST(IsSpecial)79 TEST(IsSpecial) {
80 CHECK(Double(V8_INFINITY).IsSpecial());
81 CHECK(Double(-V8_INFINITY).IsSpecial());
82 CHECK(Double(OS::nan_value()).IsSpecial());
83 uint64_t bits = V8_2PART_UINT64_C(0xFFF12345, 00000000);
84 CHECK(Double(bits).IsSpecial());
85 // Denormals are not special:
86 CHECK(!Double(5e-324).IsSpecial());
87 CHECK(!Double(-5e-324).IsSpecial());
88 // And some random numbers:
89 CHECK(!Double(0.0).IsSpecial());
90 CHECK(!Double(-0.0).IsSpecial());
91 CHECK(!Double(1.0).IsSpecial());
92 CHECK(!Double(-1.0).IsSpecial());
93 CHECK(!Double(1000000.0).IsSpecial());
94 CHECK(!Double(-1000000.0).IsSpecial());
95 CHECK(!Double(1e23).IsSpecial());
96 CHECK(!Double(-1e23).IsSpecial());
97 CHECK(!Double(1.7976931348623157e308).IsSpecial());
98 CHECK(!Double(-1.7976931348623157e308).IsSpecial());
99 }
100
101
TEST(IsInfinite)102 TEST(IsInfinite) {
103 CHECK(Double(V8_INFINITY).IsInfinite());
104 CHECK(Double(-V8_INFINITY).IsInfinite());
105 CHECK(!Double(OS::nan_value()).IsInfinite());
106 CHECK(!Double(0.0).IsInfinite());
107 CHECK(!Double(-0.0).IsInfinite());
108 CHECK(!Double(1.0).IsInfinite());
109 CHECK(!Double(-1.0).IsInfinite());
110 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
111 CHECK(!Double(min_double64).IsInfinite());
112 }
113
114
TEST(IsNan)115 TEST(IsNan) {
116 CHECK(Double(OS::nan_value()).IsNan());
117 uint64_t other_nan = V8_2PART_UINT64_C(0xFFFFFFFF, 00000001);
118 CHECK(Double(other_nan).IsNan());
119 CHECK(!Double(V8_INFINITY).IsNan());
120 CHECK(!Double(-V8_INFINITY).IsNan());
121 CHECK(!Double(0.0).IsNan());
122 CHECK(!Double(-0.0).IsNan());
123 CHECK(!Double(1.0).IsNan());
124 CHECK(!Double(-1.0).IsNan());
125 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
126 CHECK(!Double(min_double64).IsNan());
127 }
128
129
TEST(Sign)130 TEST(Sign) {
131 CHECK_EQ(1, Double(1.0).Sign());
132 CHECK_EQ(1, Double(V8_INFINITY).Sign());
133 CHECK_EQ(-1, Double(-V8_INFINITY).Sign());
134 CHECK_EQ(1, Double(0.0).Sign());
135 CHECK_EQ(-1, Double(-0.0).Sign());
136 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
137 CHECK_EQ(1, Double(min_double64).Sign());
138 }
139
140
TEST(NormalizedBoundaries)141 TEST(NormalizedBoundaries) {
142 DiyFp boundary_plus;
143 DiyFp boundary_minus;
144 DiyFp diy_fp = Double(1.5).AsNormalizedDiyFp();
145 Double(1.5).NormalizedBoundaries(&boundary_minus, &boundary_plus);
146 CHECK_EQ(diy_fp.e(), boundary_minus.e());
147 CHECK_EQ(diy_fp.e(), boundary_plus.e());
148 // 1.5 does not have a significand of the form 2^p (for some p).
149 // Therefore its boundaries are at the same distance.
150 CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f());
151 CHECK((1 << 10) == diy_fp.f() - boundary_minus.f()); // NOLINT
152
153 diy_fp = Double(1.0).AsNormalizedDiyFp();
154 Double(1.0).NormalizedBoundaries(&boundary_minus, &boundary_plus);
155 CHECK_EQ(diy_fp.e(), boundary_minus.e());
156 CHECK_EQ(diy_fp.e(), boundary_plus.e());
157 // 1.0 does have a significand of the form 2^p (for some p).
158 // Therefore its lower boundary is twice as close as the upper boundary.
159 CHECK_GT(boundary_plus.f() - diy_fp.f(), diy_fp.f() - boundary_minus.f());
160 CHECK((1 << 9) == diy_fp.f() - boundary_minus.f()); // NOLINT
161 CHECK((1 << 10) == boundary_plus.f() - diy_fp.f()); // NOLINT
162
163 uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001);
164 diy_fp = Double(min_double64).AsNormalizedDiyFp();
165 Double(min_double64).NormalizedBoundaries(&boundary_minus, &boundary_plus);
166 CHECK_EQ(diy_fp.e(), boundary_minus.e());
167 CHECK_EQ(diy_fp.e(), boundary_plus.e());
168 // min-value does not have a significand of the form 2^p (for some p).
169 // Therefore its boundaries are at the same distance.
170 CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f());
171 // Denormals have their boundaries much closer.
172 CHECK((static_cast<uint64_t>(1) << 62) ==
173 diy_fp.f() - boundary_minus.f()); // NOLINT
174
175 uint64_t smallest_normal64 = V8_2PART_UINT64_C(0x00100000, 00000000);
176 diy_fp = Double(smallest_normal64).AsNormalizedDiyFp();
177 Double(smallest_normal64).NormalizedBoundaries(&boundary_minus,
178 &boundary_plus);
179 CHECK_EQ(diy_fp.e(), boundary_minus.e());
180 CHECK_EQ(diy_fp.e(), boundary_plus.e());
181 // Even though the significand is of the form 2^p (for some p), its boundaries
182 // are at the same distance. (This is the only exception).
183 CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f());
184 CHECK((1 << 10) == diy_fp.f() - boundary_minus.f()); // NOLINT
185
186 uint64_t largest_denormal64 = V8_2PART_UINT64_C(0x000FFFFF, FFFFFFFF);
187 diy_fp = Double(largest_denormal64).AsNormalizedDiyFp();
188 Double(largest_denormal64).NormalizedBoundaries(&boundary_minus,
189 &boundary_plus);
190 CHECK_EQ(diy_fp.e(), boundary_minus.e());
191 CHECK_EQ(diy_fp.e(), boundary_plus.e());
192 CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f());
193 CHECK((1 << 11) == diy_fp.f() - boundary_minus.f()); // NOLINT
194
195 uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff);
196 diy_fp = Double(max_double64).AsNormalizedDiyFp();
197 Double(max_double64).NormalizedBoundaries(&boundary_minus, &boundary_plus);
198 CHECK_EQ(diy_fp.e(), boundary_minus.e());
199 CHECK_EQ(diy_fp.e(), boundary_plus.e());
200 // max-value does not have a significand of the form 2^p (for some p).
201 // Therefore its boundaries are at the same distance.
202 CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f());
203 CHECK((1 << 10) == diy_fp.f() - boundary_minus.f()); // NOLINT
204 }
205
206
TEST(NextDouble)207 TEST(NextDouble) {
208 CHECK_EQ(4e-324, Double(0.0).NextDouble());
209 CHECK_EQ(0.0, Double(-0.0).NextDouble());
210 CHECK_EQ(-0.0, Double(-4e-324).NextDouble());
211 Double d0(-4e-324);
212 Double d1(d0.NextDouble());
213 Double d2(d1.NextDouble());
214 CHECK_EQ(-0.0, d1.value());
215 CHECK_EQ(0.0, d2.value());
216 CHECK_EQ(4e-324, d2.NextDouble());
217 CHECK_EQ(-1.7976931348623157e308, Double(-V8_INFINITY).NextDouble());
218 CHECK_EQ(V8_INFINITY,
219 Double(V8_2PART_UINT64_C(0x7fefffff, ffffffff)).NextDouble());
220 }
221