half_float.cpp 14 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349
  1. // This file is part of Eigen, a lightweight C++ template library
  2. // for linear algebra.
  3. //
  4. // This Source Code Form is subject to the terms of the Mozilla
  5. // Public License v. 2.0. If a copy of the MPL was not distributed
  6. // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
  7. #include <sstream>
  8. #include "main.h"
  9. #include <Eigen/src/Core/arch/Default/Half.h>
  10. #define VERIFY_HALF_BITS_EQUAL(h, bits) \
  11. VERIFY_IS_EQUAL((numext::bit_cast<numext::uint16_t>(h)), (static_cast<numext::uint16_t>(bits)))
  12. // Make sure it's possible to forward declare Eigen::half
  13. namespace Eigen {
  14. struct half;
  15. }
  16. using Eigen::half;
  17. void test_conversion()
  18. {
  19. using Eigen::half_impl::__half_raw;
  20. // Round-trip bit-cast with uint16.
  21. VERIFY_IS_EQUAL(
  22. numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(1.0f))),
  23. half(1.0f));
  24. VERIFY_IS_EQUAL(
  25. numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(0.5f))),
  26. half(0.5f));
  27. VERIFY_IS_EQUAL(
  28. numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(-0.33333f))),
  29. half(-0.33333f));
  30. VERIFY_IS_EQUAL(
  31. numext::bit_cast<half>(numext::bit_cast<numext::uint16_t>(half(0.0f))),
  32. half(0.0f));
  33. // Conversion from float.
  34. VERIFY_HALF_BITS_EQUAL(half(1.0f), 0x3c00);
  35. VERIFY_HALF_BITS_EQUAL(half(0.5f), 0x3800);
  36. VERIFY_HALF_BITS_EQUAL(half(0.33333f), 0x3555);
  37. VERIFY_HALF_BITS_EQUAL(half(0.0f), 0x0000);
  38. VERIFY_HALF_BITS_EQUAL(half(-0.0f), 0x8000);
  39. VERIFY_HALF_BITS_EQUAL(half(65504.0f), 0x7bff);
  40. VERIFY_HALF_BITS_EQUAL(half(65536.0f), 0x7c00); // Becomes infinity.
  41. // Denormals.
  42. VERIFY_HALF_BITS_EQUAL(half(-5.96046e-08f), 0x8001);
  43. VERIFY_HALF_BITS_EQUAL(half(5.96046e-08f), 0x0001);
  44. VERIFY_HALF_BITS_EQUAL(half(1.19209e-07f), 0x0002);
  45. // Verify round-to-nearest-even behavior.
  46. float val1 = float(half(__half_raw(0x3c00)));
  47. float val2 = float(half(__half_raw(0x3c01)));
  48. float val3 = float(half(__half_raw(0x3c02)));
  49. VERIFY_HALF_BITS_EQUAL(half(0.5f * (val1 + val2)), 0x3c00);
  50. VERIFY_HALF_BITS_EQUAL(half(0.5f * (val2 + val3)), 0x3c02);
  51. // Conversion from int.
  52. VERIFY_HALF_BITS_EQUAL(half(-1), 0xbc00);
  53. VERIFY_HALF_BITS_EQUAL(half(0), 0x0000);
  54. VERIFY_HALF_BITS_EQUAL(half(1), 0x3c00);
  55. VERIFY_HALF_BITS_EQUAL(half(2), 0x4000);
  56. VERIFY_HALF_BITS_EQUAL(half(3), 0x4200);
  57. // Conversion from bool.
  58. VERIFY_HALF_BITS_EQUAL(half(false), 0x0000);
  59. VERIFY_HALF_BITS_EQUAL(half(true), 0x3c00);
  60. // Conversion to float.
  61. VERIFY_IS_EQUAL(float(half(__half_raw(0x0000))), 0.0f);
  62. VERIFY_IS_EQUAL(float(half(__half_raw(0x3c00))), 1.0f);
  63. // Denormals.
  64. VERIFY_IS_APPROX(float(half(__half_raw(0x8001))), -5.96046e-08f);
  65. VERIFY_IS_APPROX(float(half(__half_raw(0x0001))), 5.96046e-08f);
  66. VERIFY_IS_APPROX(float(half(__half_raw(0x0002))), 1.19209e-07f);
  67. // NaNs and infinities.
  68. VERIFY(!(numext::isinf)(float(half(65504.0f)))); // Largest finite number.
  69. VERIFY(!(numext::isnan)(float(half(0.0f))));
  70. VERIFY((numext::isinf)(float(half(__half_raw(0xfc00)))));
  71. VERIFY((numext::isnan)(float(half(__half_raw(0xfc01)))));
  72. VERIFY((numext::isinf)(float(half(__half_raw(0x7c00)))));
  73. VERIFY((numext::isnan)(float(half(__half_raw(0x7c01)))));
  74. #if !EIGEN_COMP_MSVC
  75. // Visual Studio errors out on divisions by 0
  76. VERIFY((numext::isnan)(float(half(0.0 / 0.0))));
  77. VERIFY((numext::isinf)(float(half(1.0 / 0.0))));
  78. VERIFY((numext::isinf)(float(half(-1.0 / 0.0))));
  79. #endif
  80. // Exactly same checks as above, just directly on the half representation.
  81. VERIFY(!(numext::isinf)(half(__half_raw(0x7bff))));
  82. VERIFY(!(numext::isnan)(half(__half_raw(0x0000))));
  83. VERIFY((numext::isinf)(half(__half_raw(0xfc00))));
  84. VERIFY((numext::isnan)(half(__half_raw(0xfc01))));
  85. VERIFY((numext::isinf)(half(__half_raw(0x7c00))));
  86. VERIFY((numext::isnan)(half(__half_raw(0x7c01))));
  87. #if !EIGEN_COMP_MSVC
  88. // Visual Studio errors out on divisions by 0
  89. VERIFY((numext::isnan)(half(0.0 / 0.0)));
  90. VERIFY((numext::isinf)(half(1.0 / 0.0)));
  91. VERIFY((numext::isinf)(half(-1.0 / 0.0)));
  92. #endif
  93. // Conversion to bool
  94. VERIFY(!static_cast<bool>(half(0.0)));
  95. VERIFY(!static_cast<bool>(half(-0.0)));
  96. VERIFY(static_cast<bool>(half(__half_raw(0x7bff))));
  97. VERIFY(static_cast<bool>(half(-0.33333)));
  98. VERIFY(static_cast<bool>(half(1.0)));
  99. VERIFY(static_cast<bool>(half(-1.0)));
  100. VERIFY(static_cast<bool>(half(-5.96046e-08f)));
  101. }
  102. void test_numtraits()
  103. {
  104. std::cout << "epsilon = " << NumTraits<half>::epsilon() << " (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::epsilon()) << ")" << std::endl;
  105. std::cout << "highest = " << NumTraits<half>::highest() << " (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::highest()) << ")" << std::endl;
  106. std::cout << "lowest = " << NumTraits<half>::lowest() << " (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::lowest()) << ")" << std::endl;
  107. 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;
  108. 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;
  109. std::cout << "infinity = " << NumTraits<half>::infinity() << " (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::infinity()) << ")" << std::endl;
  110. std::cout << "quiet nan = " << NumTraits<half>::quiet_NaN() << " (0x" << std::hex << numext::bit_cast<numext::uint16_t>(NumTraits<half>::quiet_NaN()) << ")" << std::endl;
  111. 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;
  112. VERIFY(NumTraits<half>::IsSigned);
  113. VERIFY_IS_EQUAL(
  114. numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::infinity()),
  115. numext::bit_cast<numext::uint16_t>(half(std::numeric_limits<float>::infinity())) );
  116. // There is no guarantee that casting a 32-bit NaN to 16-bit has a precise
  117. // bit pattern. We test that it is in fact a NaN, then test the signaling
  118. // bit (msb of significand is 1 for quiet, 0 for signaling).
  119. const numext::uint16_t HALF_QUIET_BIT = 0x0200;
  120. VERIFY(
  121. (numext::isnan)(std::numeric_limits<half>::quiet_NaN())
  122. && (numext::isnan)(half(std::numeric_limits<float>::quiet_NaN()))
  123. && ((numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::quiet_NaN()) & HALF_QUIET_BIT) > 0)
  124. && ((numext::bit_cast<numext::uint16_t>(half(std::numeric_limits<float>::quiet_NaN())) & HALF_QUIET_BIT) > 0) );
  125. // After a cast to half, a signaling NaN may become non-signaling
  126. // (e.g. in the case of casting float to native __fp16). Thus, we check that
  127. // both are NaN, and that only the `numeric_limits` version is signaling.
  128. VERIFY(
  129. (numext::isnan)(std::numeric_limits<half>::signaling_NaN())
  130. && (numext::isnan)(half(std::numeric_limits<float>::signaling_NaN()))
  131. && ((numext::bit_cast<numext::uint16_t>(std::numeric_limits<half>::signaling_NaN()) & HALF_QUIET_BIT) == 0) );
  132. VERIFY( (std::numeric_limits<half>::min)() > half(0.f) );
  133. VERIFY( (std::numeric_limits<half>::denorm_min)() > half(0.f) );
  134. VERIFY( (std::numeric_limits<half>::min)()/half(2) > half(0.f) );
  135. VERIFY_IS_EQUAL( (std::numeric_limits<half>::denorm_min)()/half(2), half(0.f) );
  136. }
  137. void test_arithmetic()
  138. {
  139. VERIFY_IS_EQUAL(float(half(2) + half(2)), 4);
  140. VERIFY_IS_EQUAL(float(half(2) + half(-2)), 0);
  141. VERIFY_IS_APPROX(float(half(0.33333f) + half(0.66667f)), 1.0f);
  142. VERIFY_IS_EQUAL(float(half(2.0f) * half(-5.5f)), -11.0f);
  143. VERIFY_IS_APPROX(float(half(1.0f) / half(3.0f)), 0.33333f);
  144. VERIFY_IS_EQUAL(float(-half(4096.0f)), -4096.0f);
  145. VERIFY_IS_EQUAL(float(-half(-4096.0f)), 4096.0f);
  146. half x(3);
  147. half y = ++x;
  148. VERIFY_IS_EQUAL(x, half(4));
  149. VERIFY_IS_EQUAL(y, half(4));
  150. y = --x;
  151. VERIFY_IS_EQUAL(x, half(3));
  152. VERIFY_IS_EQUAL(y, half(3));
  153. y = x++;
  154. VERIFY_IS_EQUAL(x, half(4));
  155. VERIFY_IS_EQUAL(y, half(3));
  156. y = x--;
  157. VERIFY_IS_EQUAL(x, half(3));
  158. VERIFY_IS_EQUAL(y, half(4));
  159. }
  160. void test_comparison()
  161. {
  162. VERIFY(half(1.0f) > half(0.5f));
  163. VERIFY(half(0.5f) < half(1.0f));
  164. VERIFY(!(half(1.0f) < half(0.5f)));
  165. VERIFY(!(half(0.5f) > half(1.0f)));
  166. VERIFY(!(half(4.0f) > half(4.0f)));
  167. VERIFY(!(half(4.0f) < half(4.0f)));
  168. VERIFY(!(half(0.0f) < half(-0.0f)));
  169. VERIFY(!(half(-0.0f) < half(0.0f)));
  170. VERIFY(!(half(0.0f) > half(-0.0f)));
  171. VERIFY(!(half(-0.0f) > half(0.0f)));
  172. VERIFY(half(0.2f) > half(-1.0f));
  173. VERIFY(half(-1.0f) < half(0.2f));
  174. VERIFY(half(-16.0f) < half(-15.0f));
  175. VERIFY(half(1.0f) == half(1.0f));
  176. VERIFY(half(1.0f) != half(2.0f));
  177. // Comparisons with NaNs and infinities.
  178. #if !EIGEN_COMP_MSVC
  179. // Visual Studio errors out on divisions by 0
  180. VERIFY(!(half(0.0 / 0.0) == half(0.0 / 0.0)));
  181. VERIFY(half(0.0 / 0.0) != half(0.0 / 0.0));
  182. VERIFY(!(half(1.0) == half(0.0 / 0.0)));
  183. VERIFY(!(half(1.0) < half(0.0 / 0.0)));
  184. VERIFY(!(half(1.0) > half(0.0 / 0.0)));
  185. VERIFY(half(1.0) != half(0.0 / 0.0));
  186. VERIFY(half(1.0) < half(1.0 / 0.0));
  187. VERIFY(half(1.0) > half(-1.0 / 0.0));
  188. #endif
  189. }
  190. void test_basic_functions()
  191. {
  192. VERIFY_IS_EQUAL(float(numext::abs(half(3.5f))), 3.5f);
  193. VERIFY_IS_EQUAL(float(abs(half(3.5f))), 3.5f);
  194. VERIFY_IS_EQUAL(float(numext::abs(half(-3.5f))), 3.5f);
  195. VERIFY_IS_EQUAL(float(abs(half(-3.5f))), 3.5f);
  196. VERIFY_IS_EQUAL(float(numext::floor(half(3.5f))), 3.0f);
  197. VERIFY_IS_EQUAL(float(floor(half(3.5f))), 3.0f);
  198. VERIFY_IS_EQUAL(float(numext::floor(half(-3.5f))), -4.0f);
  199. VERIFY_IS_EQUAL(float(floor(half(-3.5f))), -4.0f);
  200. VERIFY_IS_EQUAL(float(numext::ceil(half(3.5f))), 4.0f);
  201. VERIFY_IS_EQUAL(float(ceil(half(3.5f))), 4.0f);
  202. VERIFY_IS_EQUAL(float(numext::ceil(half(-3.5f))), -3.0f);
  203. VERIFY_IS_EQUAL(float(ceil(half(-3.5f))), -3.0f);
  204. VERIFY_IS_APPROX(float(numext::sqrt(half(0.0f))), 0.0f);
  205. VERIFY_IS_APPROX(float(sqrt(half(0.0f))), 0.0f);
  206. VERIFY_IS_APPROX(float(numext::sqrt(half(4.0f))), 2.0f);
  207. VERIFY_IS_APPROX(float(sqrt(half(4.0f))), 2.0f);
  208. VERIFY_IS_APPROX(float(numext::pow(half(0.0f), half(1.0f))), 0.0f);
  209. VERIFY_IS_APPROX(float(pow(half(0.0f), half(1.0f))), 0.0f);
  210. VERIFY_IS_APPROX(float(numext::pow(half(2.0f), half(2.0f))), 4.0f);
  211. VERIFY_IS_APPROX(float(pow(half(2.0f), half(2.0f))), 4.0f);
  212. VERIFY_IS_EQUAL(float(numext::exp(half(0.0f))), 1.0f);
  213. VERIFY_IS_EQUAL(float(exp(half(0.0f))), 1.0f);
  214. VERIFY_IS_APPROX(float(numext::exp(half(EIGEN_PI))), 20.f + float(EIGEN_PI));
  215. VERIFY_IS_APPROX(float(exp(half(EIGEN_PI))), 20.f + float(EIGEN_PI));
  216. VERIFY_IS_EQUAL(float(numext::expm1(half(0.0f))), 0.0f);
  217. VERIFY_IS_EQUAL(float(expm1(half(0.0f))), 0.0f);
  218. VERIFY_IS_APPROX(float(numext::expm1(half(2.0f))), 6.3890561f);
  219. VERIFY_IS_APPROX(float(expm1(half(2.0f))), 6.3890561f);
  220. VERIFY_IS_EQUAL(float(numext::log(half(1.0f))), 0.0f);
  221. VERIFY_IS_EQUAL(float(log(half(1.0f))), 0.0f);
  222. VERIFY_IS_APPROX(float(numext::log(half(10.0f))), 2.30273f);
  223. VERIFY_IS_APPROX(float(log(half(10.0f))), 2.30273f);
  224. VERIFY_IS_EQUAL(float(numext::log1p(half(0.0f))), 0.0f);
  225. VERIFY_IS_EQUAL(float(log1p(half(0.0f))), 0.0f);
  226. VERIFY_IS_APPROX(float(numext::log1p(half(10.0f))), 2.3978953f);
  227. VERIFY_IS_APPROX(float(log1p(half(10.0f))), 2.3978953f);
  228. VERIFY_IS_APPROX(numext::fmod(half(5.3f), half(2.0f)), half(1.3f));
  229. VERIFY_IS_APPROX(fmod(half(5.3f), half(2.0f)), half(1.3f));
  230. VERIFY_IS_APPROX(numext::fmod(half(-18.5f), half(-4.2f)), half(-1.7f));
  231. VERIFY_IS_APPROX(fmod(half(-18.5f), half(-4.2f)), half(-1.7f));
  232. }
  233. void test_trigonometric_functions()
  234. {
  235. VERIFY_IS_APPROX(numext::cos(half(0.0f)), half(cosf(0.0f)));
  236. VERIFY_IS_APPROX(cos(half(0.0f)), half(cosf(0.0f)));
  237. VERIFY_IS_APPROX(numext::cos(half(EIGEN_PI)), half(cosf(EIGEN_PI)));
  238. // VERIFY_IS_APPROX(numext::cos(half(EIGEN_PI/2)), half(cosf(EIGEN_PI/2)));
  239. // VERIFY_IS_APPROX(numext::cos(half(3*EIGEN_PI/2)), half(cosf(3*EIGEN_PI/2)));
  240. VERIFY_IS_APPROX(numext::cos(half(3.5f)), half(cosf(3.5f)));
  241. VERIFY_IS_APPROX(numext::sin(half(0.0f)), half(sinf(0.0f)));
  242. VERIFY_IS_APPROX(sin(half(0.0f)), half(sinf(0.0f)));
  243. // VERIFY_IS_APPROX(numext::sin(half(EIGEN_PI)), half(sinf(EIGEN_PI)));
  244. VERIFY_IS_APPROX(numext::sin(half(EIGEN_PI/2)), half(sinf(EIGEN_PI/2)));
  245. VERIFY_IS_APPROX(numext::sin(half(3*EIGEN_PI/2)), half(sinf(3*EIGEN_PI/2)));
  246. VERIFY_IS_APPROX(numext::sin(half(3.5f)), half(sinf(3.5f)));
  247. VERIFY_IS_APPROX(numext::tan(half(0.0f)), half(tanf(0.0f)));
  248. VERIFY_IS_APPROX(tan(half(0.0f)), half(tanf(0.0f)));
  249. // VERIFY_IS_APPROX(numext::tan(half(EIGEN_PI)), half(tanf(EIGEN_PI)));
  250. // VERIFY_IS_APPROX(numext::tan(half(EIGEN_PI/2)), half(tanf(EIGEN_PI/2)));
  251. //VERIFY_IS_APPROX(numext::tan(half(3*EIGEN_PI/2)), half(tanf(3*EIGEN_PI/2)));
  252. VERIFY_IS_APPROX(numext::tan(half(3.5f)), half(tanf(3.5f)));
  253. }
  254. void test_array()
  255. {
  256. typedef Array<half,1,Dynamic> ArrayXh;
  257. Index size = internal::random<Index>(1,10);
  258. Index i = internal::random<Index>(0,size-1);
  259. ArrayXh a1 = ArrayXh::Random(size), a2 = ArrayXh::Random(size);
  260. VERIFY_IS_APPROX( a1+a1, half(2)*a1 );
  261. VERIFY( (a1.abs() >= half(0)).all() );
  262. VERIFY_IS_APPROX( (a1*a1).sqrt(), a1.abs() );
  263. VERIFY( ((a1.min)(a2) <= (a1.max)(a2)).all() );
  264. a1(i) = half(-10.);
  265. VERIFY_IS_EQUAL( a1.minCoeff(), half(-10.) );
  266. a1(i) = half(10.);
  267. VERIFY_IS_EQUAL( a1.maxCoeff(), half(10.) );
  268. std::stringstream ss;
  269. ss << a1;
  270. }
  271. void test_product()
  272. {
  273. typedef Matrix<half,Dynamic,Dynamic> MatrixXh;
  274. Index rows = internal::random<Index>(1,EIGEN_TEST_MAX_SIZE);
  275. Index cols = internal::random<Index>(1,EIGEN_TEST_MAX_SIZE);
  276. Index depth = internal::random<Index>(1,EIGEN_TEST_MAX_SIZE);
  277. MatrixXh Ah = MatrixXh::Random(rows,depth);
  278. MatrixXh Bh = MatrixXh::Random(depth,cols);
  279. MatrixXh Ch = MatrixXh::Random(rows,cols);
  280. MatrixXf Af = Ah.cast<float>();
  281. MatrixXf Bf = Bh.cast<float>();
  282. MatrixXf Cf = Ch.cast<float>();
  283. VERIFY_IS_APPROX(Ch.noalias()+=Ah*Bh, (Cf.noalias()+=Af*Bf).cast<half>());
  284. }
  285. EIGEN_DECLARE_TEST(half_float)
  286. {
  287. CALL_SUBTEST(test_numtraits());
  288. for(int i = 0; i < g_repeat; i++) {
  289. CALL_SUBTEST(test_conversion());
  290. CALL_SUBTEST(test_arithmetic());
  291. CALL_SUBTEST(test_comparison());
  292. CALL_SUBTEST(test_basic_functions());
  293. CALL_SUBTEST(test_trigonometric_functions());
  294. CALL_SUBTEST(test_array());
  295. CALL_SUBTEST(test_product());
  296. }
  297. }