aboutsummaryrefslogtreecommitdiffhomepage
path: root/test/half_float.cpp
blob: 729de1bc725d2b0d4db43c7f9e48f90de92b50be (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#include <sstream>

#include "main.h"

#include <Eigen/src/Core/arch/Default/Half.h>

#define VERIFY_HALF_BITS_EQUAL(h, bits) \
  VERIFY_IS_EQUAL((numext::bit_cast<numext::uint16_t>(h)), (static_cast<numext::uint16_t>(bits)))

// Make sure it's possible to forward declare Eigen::half
namespace Eigen {
struct half;
}

using Eigen::half;

void test_conversion()
{
  using Eigen::half_impl::__half_raw;

  // Round-trip bit-cast with uint16.
  VERIFY_IS_EQUAL(
    numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(1.0f))),
    half(1.0f));
  VERIFY_IS_EQUAL(
    numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(0.5f))),
    half(0.5f));
  VERIFY_IS_EQUAL(
    numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(-0.33333f))),
    half(-0.33333f));
   VERIFY_IS_EQUAL(
    numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(0.0f))),
    half(0.0f));

  // Conversion from float.
  VERIFY_HALF_BITS_EQUAL(half(1.0f), 0x3c00);
  VERIFY_HALF_BITS_EQUAL(half(0.5f), 0x3800);
  VERIFY_HALF_BITS_EQUAL(half(0.33333f), 0x3555);
  VERIFY_HALF_BITS_EQUAL(half(0.0f), 0x0000);
  VERIFY_HALF_BITS_EQUAL(half(-0.0f), 0x8000);
  VERIFY_HALF_BITS_EQUAL(half(65504.0f), 0x7bff);
  VERIFY_HALF_BITS_EQUAL(half(65536.0f), 0x7c00);  // Becomes infinity.

  // Denormals.
  VERIFY_HALF_BITS_EQUAL(half(-5.96046e-08f), 0x8001);
  VERIFY_HALF_BITS_EQUAL(half(5.96046e-08f), 0x0001);
  VERIFY_HALF_BITS_EQUAL(half(1.19209e-07f), 0x0002);

  // Verify round-to-nearest-even behavior.
  float val1 = float(half(__half_raw(0x3c00)));
  float val2 = float(half(__half_raw(0x3c01)));
  float val3 = float(half(__half_raw(0x3c02)));
  VERIFY_HALF_BITS_EQUAL(half(0.5f * (val1 + val2)), 0x3c00);
  VERIFY_HALF_BITS_EQUAL(half(0.5f * (val2 + val3)), 0x3c02);

  // Conversion from int.
  VERIFY_HALF_BITS_EQUAL(half(-1), 0xbc00);
  VERIFY_HALF_BITS_EQUAL(half(0), 0x0000);
  VERIFY_HALF_BITS_EQUAL(half(1), 0x3c00);
  VERIFY_HALF_BITS_EQUAL(half(2), 0x4000);
  VERIFY_HALF_BITS_EQUAL(half(3), 0x4200);

  // Conversion from bool.
  VERIFY_HALF_BITS_EQUAL(half(false), 0x0000);
  VERIFY_HALF_BITS_EQUAL(half(true), 0x3c00);

  // Conversion to float.
  VERIFY_IS_EQUAL(float(half(__half_raw(0x0000))), 0.0f);
  VERIFY_IS_EQUAL(float(half(__half_raw(0x3c00))), 1.0f);

  // Denormals.
  VERIFY_IS_APPROX(float(half(__half_raw(0x8001))), -5.96046e-08f);
  VERIFY_IS_APPROX(float(half(__half_raw(0x0001))), 5.96046e-08f);
  VERIFY_IS_APPROX(float(half(__half_raw(0x0002))), 1.19209e-07f);

  // NaNs and infinities.
  VERIFY(!(numext::isinf)(float(half(65504.0f))));  // Largest finite number.
  VERIFY(!(numext::isnan)(float(half(0.0f))));
  VERIFY((numext::isinf)(float(half(__half_raw(0xfc00)))));
  VERIFY((numext::isnan)(float(half(__half_raw(0xfc01)))));
  VERIFY((numext::isinf)(float(half(__half_raw(0x7c00)))));
  VERIFY((numext::isnan)(float(half(__half_raw(0x7c01)))));

#if !EIGEN_COMP_MSVC
  // Visual Studio errors out on divisions by 0
  VERIFY((numext::isnan)(float(half(0.0 / 0.0))));
  VERIFY((numext::isinf)(float(half(1.0 / 0.0))));
  VERIFY((numext::isinf)(float(half(-1.0 / 0.0))));
#endif

  // Exactly same checks as above, just directly on the half representation.
  VERIFY(!(numext::isinf)(half(__half_raw(0x7bff))));
  VERIFY(!(numext::isnan)(half(__half_raw(0x0000))));
  VERIFY((numext::isinf)(half(__half_raw(0xfc00))));
  VERIFY((numext::isnan)(half(__half_raw(0xfc01))));
  VERIFY((numext::isinf)(half(__half_raw(0x7c00))));
  VERIFY((numext::isnan)(half(__half_raw(0x7c01))));

#if !EIGEN_COMP_MSVC
  // Visual Studio errors out on divisions by 0
  VERIFY((numext::isnan)(half(0.0 / 0.0)));
  VERIFY((numext::isinf)(half(1.0 / 0.0)));
  VERIFY((numext::isinf)(half(-1.0 / 0.0)));
#endif

  // Conversion to bool
  VERIFY(!static_cast<bool>(half(0.0)));
  VERIFY(!static_cast<bool>(half(-0.0)));
  VERIFY(static_cast<bool>(half(__half_raw(0x7bff))));
  VERIFY(static_cast<bool>(half(-0.33333)));
  VERIFY(static_cast<bool>(half(1.0)));
  VERIFY(static_cast<bool>(half(-1.0)));
  VERIFY(static_cast<bool>(half(-5.96046e-08f)));
}

void test_numtraits()
{
  std::cout << "epsilon       = " << NumTraits<half>::epsilon() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::epsilon()) << ")" << std::endl;
  std::cout << "highest       = " << NumTraits<half>::highest() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::highest()) << ")" << std::endl;
  std::cout << "lowest        = " << NumTraits<half>::lowest() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::lowest()) << ")" << std::endl;
  std::cout << "min           = " << (std::numeric_limits<half>::min)() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(half((std::numeric_limits<half>::min)())) << ")" << std::endl;
  std::cout << "denorm min    = " << (std::numeric_limits<half>::denorm_min)() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(half((std::numeric_limits<half>::denorm_min)())) << ")" << std::endl;
  std::cout << "infinity      = " << NumTraits<half>::infinity() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::infinity()) << ")" << std::endl;
  std::cout << "quiet nan     = " << NumTraits<half>::quiet_NaN() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::quiet_NaN()) << ")" << std::endl;
  std::cout << "signaling nan = " << std::numeric_limits<half>::signaling_NaN() << "  (0x" << std::hex << numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::signaling_NaN()) << ")" << std::endl;

  VERIFY(NumTraits<half>::IsSigned);

  VERIFY_IS_EQUAL(
    numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::infinity()),
    numext::bit_cast<numext::uint16_t>(half(std::numeric_limits<float>::infinity())) );
  // There is no guarantee that casting a 32-bit NaN to 16-bit has a precise
  // bit pattern.  We test that it is in fact a NaN, then test the signaling
  // bit (msb of significand is 1 for quiet, 0 for signaling).
  const numext::uint16_t HALF_QUIET_BIT = 0x0200;
  VERIFY(
    (numext::isnan)(std::numeric_limits<half>::quiet_NaN())
    && (numext::isnan)(half(std::numeric_limits<float>::quiet_NaN()))
    && ((numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::quiet_NaN()) & HALF_QUIET_BIT) > 0)
    && ((numext::bit_cast<numext::uint16_t>(half(std::numeric_limits<float>::quiet_NaN())) & HALF_QUIET_BIT) > 0) );
  // After a cast to half, a signaling NaN may become non-signaling
  // (e.g. in the case of casting float to native __fp16). Thus, we check that
  // both are NaN, and that only the `numeric_limits` version is signaling.
  VERIFY(
    (numext::isnan)(std::numeric_limits<half>::signaling_NaN())
    && (numext::isnan)(half(std::numeric_limits<float>::signaling_NaN()))
    && ((numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::signaling_NaN()) & HALF_QUIET_BIT) == 0) );

  VERIFY( (std::numeric_limits<half>::min)() > half(0.f) );
  VERIFY( (std::numeric_limits<half>::denorm_min)() > half(0.f) );
  VERIFY( (std::numeric_limits<half>::min)()/half(2) > half(0.f) );
  VERIFY_IS_EQUAL( (std::numeric_limits<half>::denorm_min)()/half(2), half(0.f) );
}

void test_arithmetic()
{
  VERIFY_IS_EQUAL(float(half(2) + half(2)), 4);
  VERIFY_IS_EQUAL(float(half(2) + half(-2)), 0);
  VERIFY_IS_APPROX(float(half(0.33333f) + half(0.66667f)), 1.0f);
  VERIFY_IS_EQUAL(float(half(2.0f) * half(-5.5f)), -11.0f);
  VERIFY_IS_APPROX(float(half(1.0f) / half(3.0f)), 0.33333f);
  VERIFY_IS_EQUAL(float(-half(4096.0f)), -4096.0f);
  VERIFY_IS_EQUAL(float(-half(-4096.0f)), 4096.0f);
  
  half x(3);
  half y = ++x;
  VERIFY_IS_EQUAL(x, half(4));
  VERIFY_IS_EQUAL(y, half(4));
  y = --x;
  VERIFY_IS_EQUAL(x, half(3));
  VERIFY_IS_EQUAL(y, half(3));
  y = x++;
  VERIFY_IS_EQUAL(x, half(4));
  VERIFY_IS_EQUAL(y, half(3));
  y = x--;
  VERIFY_IS_EQUAL(x, half(3));
  VERIFY_IS_EQUAL(y, half(4));
}

void test_comparison()
{
  VERIFY(half(1.0f) > half(0.5f));
  VERIFY(half(0.5f) < half(1.0f));
  VERIFY(!(half(1.0f) < half(0.5f)));
  VERIFY(!(half(0.5f) > half(1.0f)));

  VERIFY(!(half(4.0f) > half(4.0f)));
  VERIFY(!(half(4.0f) < half(4.0f)));

  VERIFY(!(half(0.0f) < half(-0.0f)));
  VERIFY(!(half(-0.0f) < half(0.0f)));
  VERIFY(!(half(0.0f) > half(-0.0f)));
  VERIFY(!(half(-0.0f) > half(0.0f)));

  VERIFY(half(0.2f) > half(-1.0f));
  VERIFY(half(-1.0f) < half(0.2f));
  VERIFY(half(-16.0f) < half(-15.0f));

  VERIFY(half(1.0f) == half(1.0f));
  VERIFY(half(1.0f) != half(2.0f));

  // Comparisons with NaNs and infinities.
#if !EIGEN_COMP_MSVC
  // Visual Studio errors out on divisions by 0
  VERIFY(!(half(0.0 / 0.0) == half(0.0 / 0.0)));
  VERIFY(half(0.0 / 0.0) != half(0.0 / 0.0));

  VERIFY(!(half(1.0) == half(0.0 / 0.0)));
  VERIFY(!(half(1.0) < half(0.0 / 0.0)));
  VERIFY(!(half(1.0) > half(0.0 / 0.0)));
  VERIFY(half(1.0) != half(0.0 / 0.0));

  VERIFY(half(1.0) < half(1.0 / 0.0));
  VERIFY(half(1.0) > half(-1.0 / 0.0));
#endif
}

void test_basic_functions()
{
  VERIFY_IS_EQUAL(float(numext::abs(half(3.5f))), 3.5f);
  VERIFY_IS_EQUAL(float(abs(half(3.5f))), 3.5f);
  VERIFY_IS_EQUAL(float(numext::abs(half(-3.5f))), 3.5f);
  VERIFY_IS_EQUAL(float(abs(half(-3.5f))), 3.5f);

  VERIFY_IS_EQUAL(float(numext::floor(half(3.5f))), 3.0f);
  VERIFY_IS_EQUAL(float(floor(half(3.5f))), 3.0f);
  VERIFY_IS_EQUAL(float(numext::floor(half(-3.5f))), -4.0f);
  VERIFY_IS_EQUAL(float(floor(half(-3.5f))), -4.0f);

  VERIFY_IS_EQUAL(float(numext::ceil(half(3.5f))), 4.0f);
  VERIFY_IS_EQUAL(float(ceil(half(3.5f))), 4.0f);
  VERIFY_IS_EQUAL(float(numext::ceil(half(-3.5f))), -3.0f);
  VERIFY_IS_EQUAL(float(ceil(half(-3.5f))), -3.0f);

  VERIFY_IS_APPROX(float(numext::sqrt(half(0.0f))), 0.0f);
  VERIFY_IS_APPROX(float(sqrt(half(0.0f))), 0.0f);
  VERIFY_IS_APPROX(float(numext::sqrt(half(4.0f))), 2.0f);
  VERIFY_IS_APPROX(float(sqrt(half(4.0f))), 2.0f);

  VERIFY_IS_APPROX(float(numext::pow(half(0.0f), half(1.0f))), 0.0f);
  VERIFY_IS_APPROX(float(pow(half(0.0f), half(1.0f))), 0.0f);
  VERIFY_IS_APPROX(float(numext::pow(half(2.0f), half(2.0f))), 4.0f);
  VERIFY_IS_APPROX(float(pow(half(2.0f), half(2.0f))), 4.0f);

  VERIFY_IS_EQUAL(float(numext::exp(half(0.0f))), 1.0f);
  VERIFY_IS_EQUAL(float(exp(half(0.0f))), 1.0f);
  VERIFY_IS_APPROX(float(numext::exp(half(EIGEN_PI))), 20.f + float(EIGEN_PI));
  VERIFY_IS_APPROX(float(exp(half(EIGEN_PI))), 20.f + float(EIGEN_PI));

  VERIFY_IS_EQUAL(float(numext::expm1(half(0.0f))), 0.0f);
  VERIFY_IS_EQUAL(float(expm1(half(0.0f))), 0.0f);
  VERIFY_IS_APPROX(float(numext::expm1(half(2.0f))), 6.3890561f);
  VERIFY_IS_APPROX(float(expm1(half(2.0f))), 6.3890561f);

  VERIFY_IS_EQUAL(float(numext::log(half(1.0f))), 0.0f);
  VERIFY_IS_EQUAL(float(log(half(1.0f))), 0.0f);
  VERIFY_IS_APPROX(float(numext::log(half(10.0f))), 2.30273f);
  VERIFY_IS_APPROX(float(log(half(10.0f))), 2.30273f);

  VERIFY_IS_EQUAL(float(numext::log1p(half(0.0f))), 0.0f);
  VERIFY_IS_EQUAL(float(log1p(half(0.0f))), 0.0f);
  VERIFY_IS_APPROX(float(numext::log1p(half(10.0f))), 2.3978953f);
  VERIFY_IS_APPROX(float(log1p(half(10.0f))), 2.3978953f);
  
  VERIFY_IS_APPROX(numext::fmod(half(5.3f), half(2.0f)), half(1.3f));
  VERIFY_IS_APPROX(fmod(half(5.3f), half(2.0f)), half(1.3f));
  VERIFY_IS_APPROX(numext::fmod(half(-18.5f), half(-4.2f)), half(-1.7f));
  VERIFY_IS_APPROX(fmod(half(-18.5f), half(-4.2f)), half(-1.7f));
}

void test_trigonometric_functions()
{
  VERIFY_IS_APPROX(numext::cos(half(0.0f)), half(cosf(0.0f)));
  VERIFY_IS_APPROX(cos(half(0.0f)), half(cosf(0.0f)));
  VERIFY_IS_APPROX(numext::cos(half(EIGEN_PI)), half(cosf(EIGEN_PI)));
  // VERIFY_IS_APPROX(numext::cos(half(EIGEN_PI/2)), half(cosf(EIGEN_PI/2)));
  // VERIFY_IS_APPROX(numext::cos(half(3*EIGEN_PI/2)), half(cosf(3*EIGEN_PI/2)));
  VERIFY_IS_APPROX(numext::cos(half(3.5f)), half(cosf(3.5f)));

  VERIFY_IS_APPROX(numext::sin(half(0.0f)), half(sinf(0.0f)));
  VERIFY_IS_APPROX(sin(half(0.0f)), half(sinf(0.0f)));
  //  VERIFY_IS_APPROX(numext::sin(half(EIGEN_PI)), half(sinf(EIGEN_PI)));
  VERIFY_IS_APPROX(numext::sin(half(EIGEN_PI/2)), half(sinf(EIGEN_PI/2)));
  VERIFY_IS_APPROX(numext::sin(half(3*EIGEN_PI/2)), half(sinf(3*EIGEN_PI/2)));
  VERIFY_IS_APPROX(numext::sin(half(3.5f)), half(sinf(3.5f)));

  VERIFY_IS_APPROX(numext::tan(half(0.0f)), half(tanf(0.0f)));
  VERIFY_IS_APPROX(tan(half(0.0f)), half(tanf(0.0f)));
  //  VERIFY_IS_APPROX(numext::tan(half(EIGEN_PI)), half(tanf(EIGEN_PI)));
  //  VERIFY_IS_APPROX(numext::tan(half(EIGEN_PI/2)), half(tanf(EIGEN_PI/2)));
  //VERIFY_IS_APPROX(numext::tan(half(3*EIGEN_PI/2)), half(tanf(3*EIGEN_PI/2)));
  VERIFY_IS_APPROX(numext::tan(half(3.5f)), half(tanf(3.5f)));
}

void test_array()
{
  typedef Array<half,1,Dynamic> ArrayXh;
  Index size = internal::random<Index>(1,10);
  Index i = internal::random<Index>(0,size-1);
  ArrayXh a1 = ArrayXh::Random(size), a2 = ArrayXh::Random(size);
  VERIFY_IS_APPROX( a1+a1, half(2)*a1 );
  VERIFY( (a1.abs() >= half(0)).all() );
  VERIFY_IS_APPROX( (a1*a1).sqrt(), a1.abs() );

  VERIFY( ((a1.min)(a2) <= (a1.max)(a2)).all() );
  a1(i) = half(-10.);
  VERIFY_IS_EQUAL( a1.minCoeff(), half(-10.) );
  a1(i) = half(10.);
  VERIFY_IS_EQUAL( a1.maxCoeff(), half(10.) );

  std::stringstream ss;
  ss << a1;
}

void test_product()
{
  typedef Matrix<half,Dynamic,Dynamic> MatrixXh;
  Index rows  = internal::random<Index>(1,EIGEN_TEST_MAX_SIZE);
  Index cols  = internal::random<Index>(1,EIGEN_TEST_MAX_SIZE);
  Index depth = internal::random<Index>(1,EIGEN_TEST_MAX_SIZE);
  MatrixXh Ah = MatrixXh::Random(rows,depth);
  MatrixXh Bh = MatrixXh::Random(depth,cols);
  MatrixXh Ch = MatrixXh::Random(rows,cols);
  MatrixXf Af = Ah.cast<float>();
  MatrixXf Bf = Bh.cast<float>();
  MatrixXf Cf = Ch.cast<float>();
  VERIFY_IS_APPROX(Ch.noalias()+=Ah*Bh, (Cf.noalias()+=Af*Bf).cast<half>());
}

EIGEN_DECLARE_TEST(half_float)
{
  CALL_SUBTEST(test_numtraits());
  for(int i = 0; i < g_repeat; i++) {
    CALL_SUBTEST(test_conversion());
    CALL_SUBTEST(test_arithmetic());
    CALL_SUBTEST(test_comparison());
    CALL_SUBTEST(test_basic_functions());
    CALL_SUBTEST(test_trigonometric_functions());
    CALL_SUBTEST(test_array());
    CALL_SUBTEST(test_product());
  }
}