src/gromacs/simd/tests/simd4_floatingpoint.cpp

   1 /*
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   6  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   7  * and including many others, as listed in the AUTHORS file in the
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   9  *
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  36 #include "gmxpre.h"
  37
  38 #include <cmath>
  39
  40 #include "gromacs/math/units.h"
  41 #include "gromacs/math/utilities.h"
  42 #include "gromacs/simd/simd.h"
  43 #include "gromacs/utility/basedefinitions.h"
  44
  45 #include "testutils/testasserts.h"
  46
  47 #include "data.h"
  48 #include "simd4.h"
  49
  50 #if GMX_SIMD
  51
  52 namespace gmx
  53 {
  54 namespace test
  55 {
  56 namespace
  57 {
  58
  59 /*! \cond internal */
  60 /*! \addtogroup module_simd */
  61 /*! \{ */
  62
  63 #    if GMX_SIMD4_HAVE_REAL
  64
  65 /*! \brief Test fixture for SIMD4 floating-point operations (identical to the SIMD4 \ref Simd4Test) */
  66 typedef Simd4Test Simd4FloatingpointTest;
  67
  68 TEST_F(Simd4FloatingpointTest, setZero)
  69 {
  70     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(0.0), setZero());
  71 }
  72
  73 TEST_F(Simd4FloatingpointTest, set)
  74 {
  75     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(c1), Simd4Real(c1));
  76 }
  77
  78 TEST_F(Simd4FloatingpointTest, add)
  79 {
  80     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0 + c3, c1 + c4, c2 + c5), rSimd4_c0c1c2 + rSimd4_c3c4c5);
  81 }
  82
  83 TEST_F(Simd4FloatingpointTest, sub)
  84 {
  85     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0 - c3, c1 - c4, c2 - c5), rSimd4_c0c1c2 - rSimd4_c3c4c5);
  86 }
  87
  88 TEST_F(Simd4FloatingpointTest, mul)
  89 {
  90     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0 * c3, c1 * c4, c2 * c5), rSimd4_c0c1c2 * rSimd4_c3c4c5);
  91 }
  92
  93 TEST_F(Simd4FloatingpointTest, fma)
  94 {
  95     // The last bit of FMA operations depends on hardware, so we don't require exact match
  96     GMX_EXPECT_SIMD4_REAL_NEAR(setSimd4RealFrom3R(c0 * c3 + c6, c1 * c4 + c7, c2 * c5 + c8),
  97                                fma(rSimd4_c0c1c2, rSimd4_c3c4c5, rSimd4_c6c7c8));
  98 }
  99
 100 TEST_F(Simd4FloatingpointTest, fms)
 101 {
 102     // The last bit of FMA operations depends on hardware, so we don't require exact match
 103     GMX_EXPECT_SIMD4_REAL_NEAR(setSimd4RealFrom3R(c0 * c3 - c6, c1 * c4 - c7, c2 * c5 - c8),
 104                                fms(rSimd4_c0c1c2, rSimd4_c3c4c5, rSimd4_c6c7c8));
 105 }
 106
 107 TEST_F(Simd4FloatingpointTest, fnma)
 108 {
 109     // The last bit of FMA operations depends on hardware, so we don't require exact match
 110     GMX_EXPECT_SIMD4_REAL_NEAR(setSimd4RealFrom3R(c6 - c0 * c3, c7 - c1 * c4, c8 - c2 * c5),
 111                                fnma(rSimd4_c0c1c2, rSimd4_c3c4c5, rSimd4_c6c7c8));
 112 }
 113
 114 TEST_F(Simd4FloatingpointTest, fnms)
 115 {
 116     // The last bit of FMA operations depends on hardware, so we don't require exact match
 117     GMX_EXPECT_SIMD4_REAL_NEAR(setSimd4RealFrom3R(-c0 * c3 - c6, -c1 * c4 - c7, -c2 * c5 - c8),
 118                                fnms(rSimd4_c0c1c2, rSimd4_c3c4c5, rSimd4_c6c7c8));
 119 }
 120
 121 TEST_F(Simd4FloatingpointTest, abs)
 122 {
 123     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_c0c1c2, abs(rSimd4_c0c1c2)); // fabs(x)=x
 124     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_c0c1c2, abs(rSimd4_m0m1m2)); // fabs(-x)=x
 125 }
 126
 127 TEST_F(Simd4FloatingpointTest, neg)
 128 {
 129     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_m0m1m2, -(rSimd4_c0c1c2)); // fneg(x)=-x
 130     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_c0c1c2, -(rSimd4_m0m1m2)); // fneg(-x)=x
 131 }
 132
 133 #        if GMX_SIMD_HAVE_LOGICAL
 134 TEST_F(Simd4FloatingpointTest, and)
 135 {
 136     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_logicalResultAnd, (rSimd4_logicalA & rSimd4_logicalB));
 137 }
 138
 139 TEST_F(Simd4FloatingpointTest, or)
 140 {
 141     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_logicalResultOr, (rSimd4_logicalA | rSimd4_logicalB));
 142 }
 143
 144 TEST_F(Simd4FloatingpointTest, xor)
 145 {
 146     /* Test xor by taking xor with a number and its negative. This should result
 147      * in only the sign bit being set. We then use this bit change the sign of
 148      * different numbers.
 149      */
 150     Simd4Real signbit = Simd4Real(c1) ^ Simd4Real(-c1);
 151     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(-c2, c3, -c4), signbit ^ setSimd4RealFrom3R(c2, -c3, c4));
 152 }
 153
 154 TEST_F(Simd4FloatingpointTest, andNot)
 155 {
 156     /* Use xor (which we already tested, so fix that first if both tests fail)
 157      * to extract the sign bit, and then use andnot to take absolute values.
 158      */
 159     Simd4Real signbit = Simd4Real(c1) ^ Simd4Real(-c1);
 160     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c2, c3, c4),
 161                              andNot(signbit, setSimd4RealFrom3R(-c2, c3, -c4)));
 162 }
 163
 164 #        endif
 165
 166 TEST_F(Simd4FloatingpointTest, max)
 167 {
 168     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c3, c1, c4), max(rSimd4_c0c1c2, rSimd4_c3c0c4));
 169     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c3, c1, c4), max(rSimd4_c3c0c4, rSimd4_c0c1c2));
 170     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(-c0, -c0, -c2), max(rSimd4_m0m1m2, rSimd4_m3m0m4));
 171     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(-c0, -c0, -c2), max(rSimd4_m3m0m4, rSimd4_m0m1m2));
 172 }
 173
 174 TEST_F(Simd4FloatingpointTest, min)
 175 {
 176     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0, c0, c2), min(rSimd4_c0c1c2, rSimd4_c3c0c4));
 177     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0, c0, c2), min(rSimd4_c3c0c4, rSimd4_c0c1c2));
 178     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(-c3, -c1, -c4), min(rSimd4_m0m1m2, rSimd4_m3m0m4));
 179     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(-c3, -c1, -c4), min(rSimd4_m3m0m4, rSimd4_m0m1m2));
 180 }
 181
 182 TEST_F(Simd4FloatingpointTest, round)
 183 {
 184     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(2), round(Simd4Real(2.25)));
 185     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(4), round(Simd4Real(3.75)));
 186     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(-2), round(Simd4Real(-2.25)));
 187     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(-4), round(Simd4Real(-3.75)));
 188 }
 189
 190 TEST_F(Simd4FloatingpointTest, trunc)
 191 {
 192     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(2), trunc(rSimd4_2p25));
 193     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(3), trunc(rSimd4_3p75));
 194     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(-2), trunc(rSimd4_m2p25));
 195     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom1R(-3), trunc(rSimd4_m3p75));
 196 }
 197
 198 /* We do extensive 1/sqrt(x) and 1/x accuracy testing in the tests for
 199  * the SIMD math functions, so we just make sure the lookup instructions
 200  * appear to work for a few values here.
 201  */
 202 TEST_F(Simd4FloatingpointTest, gmxSimd4RsqrtR)
 203 {
 204     Simd4Real x   = setSimd4RealFrom3R(4.0, M_PI, 1234567890.0);
 205     Simd4Real ref = setSimd4RealFrom3R(0.5, 1.0 / std::sqrt(M_PI), 1.0 / std::sqrt(1234567890.0));
 206     int       shiftbits = std::numeric_limits<real>::digits - GMX_SIMD_RSQRT_BITS;
 207
 208     if (shiftbits < 0)
 209     {
 210         shiftbits = 0;
 211     }
 212
 213     // The allowed Ulp deviation is 2 to the power of the number of mantissa
 214     // digits, minus the number of bits provided by the table lookup
 215     setUlpTol(1LL << shiftbits);
 216     GMX_EXPECT_SIMD4_REAL_NEAR(ref, rsqrt(x));
 217 }
 218
 219 TEST_F(Simd4FloatingpointTest, cmpEqAndSelectByMask)
 220 {
 221     Simd4Bool eq = rSimd4_c4c6c8 == rSimd4_c6c7c8;
 222     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(0, 0, c2), selectByMask(rSimd4_c0c1c2, eq));
 223 }
 224
 225 TEST_F(Simd4FloatingpointTest, selectByNotMask)
 226 {
 227     Simd4Bool eq = rSimd4_c4c6c8 == rSimd4_c6c7c8;
 228     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0, c1, 0), selectByNotMask(rSimd4_c0c1c2, eq));
 229 }
 230
 231 TEST_F(Simd4FloatingpointTest, cmpNe)
 232 {
 233     Simd4Bool eq = rSimd4_c4c6c8 != rSimd4_c6c7c8;
 234     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0, c1, 0), selectByMask(rSimd4_c0c1c2, eq));
 235 }
 236
 237 TEST_F(Simd4FloatingpointTest, cmpLe)
 238 {
 239     Simd4Bool le = rSimd4_c4c6c8 <= rSimd4_c6c7c8;
 240     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_c0c1c2, selectByMask(rSimd4_c0c1c2, le));
 241 }
 242
 243 TEST_F(Simd4FloatingpointTest, cmpLt)
 244 {
 245     Simd4Bool lt = rSimd4_c4c6c8 < rSimd4_c6c7c8;
 246     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c0, c1, 0), selectByMask(rSimd4_c0c1c2, lt));
 247 }
 248
 249 TEST_F(Simd4FloatingpointTest, andB)
 250 {
 251     Simd4Bool eq = rSimd4_c4c6c8 == rSimd4_c6c7c8;
 252     Simd4Bool le = rSimd4_c4c6c8 <= rSimd4_c6c7c8;
 253     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(0, 0, c2), selectByMask(rSimd4_c0c1c2, (eq && le)));
 254 }
 255
 256 TEST_F(Simd4FloatingpointTest, orB)
 257 {
 258     Simd4Bool eq = rSimd4_c4c6c8 == rSimd4_c6c7c8;
 259     Simd4Bool lt = rSimd4_c4c6c8 < rSimd4_c6c7c8;
 260     GMX_EXPECT_SIMD4_REAL_EQ(rSimd4_c0c1c2, selectByMask(rSimd4_c0c1c2, (eq || lt)));
 261 }
 262
 263 TEST_F(Simd4FloatingpointTest, anyTrue)
 264 {
 265     Simd4Bool eq;
 266
 267     /* this test is a bit tricky since we don't know the simd width.
 268      * We cannot check for truth values for "any" element beyond the first,
 269      * since that part of the data will not be used if simd width is 1.
 270      */
 271     eq = (rSimd4_c4c6c8 == setSimd4RealFrom3R(c4, 0, 0));
 272     EXPECT_TRUE(anyTrue(eq));
 273
 274     eq = (rSimd4_c0c1c2 == rSimd4_c3c4c5);
 275     EXPECT_FALSE(anyTrue(eq));
 276 }
 277
 278 TEST_F(Simd4FloatingpointTest, blend)
 279 {
 280     Simd4Bool lt = rSimd4_c4c6c8 < rSimd4_c6c7c8;
 281     GMX_EXPECT_SIMD4_REAL_EQ(setSimd4RealFrom3R(c3, c4, c2), blend(rSimd4_c0c1c2, rSimd4_c3c4c5, lt));
 282 }
 283
 284 TEST_F(Simd4FloatingpointTest, reduce)
 285 {
 286     // The horizontal sum of the SIMD variable depends on the width, so
 287     // simply store it an extra time and calculate what the sum should be
 288     std::vector<real> v   = simd4Real2Vector(rSimd4_c3c4c5);
 289     real              sum = 0.0;
 290
 291     for (int i = 0; i < GMX_SIMD4_WIDTH; i++)
 292     {
 293         sum += v[i];
 294     }
 295
 296     EXPECT_REAL_EQ_TOL(sum, reduce(rSimd4_c3c4c5), defaultRealTolerance());
 297 }
 298
 299
 300 TEST_F(Simd4FloatingpointTest, dotProduct)
 301 {
 302     real res = c0 * c3 + c1 * c4 + c2 * c5;
 303
 304     EXPECT_REAL_EQ_TOL(res, dotProduct(rSimd4_c0c1c2, rSimd4_c3c4c5), defaultRealTolerance());
 305 }
 306
 307 TEST_F(Simd4FloatingpointTest, transpose)
 308 {
 309     Simd4Real v0, v1, v2, v3;
 310     int       i;
 311     // aligned pointers
 312     alignas(GMX_SIMD_ALIGNMENT) real p0[4 * GMX_SIMD4_WIDTH];
 313     real*                            p1 = p0 + GMX_SIMD4_WIDTH;
 314     real*                            p2 = p0 + 2 * GMX_SIMD4_WIDTH;
 315     real*                            p3 = p0 + 3 * GMX_SIMD4_WIDTH;
 316
 317     // Assign data with tens as row, single-digit as column
 318     for (i = 0; i < 4; i++)
 319     {
 320         // Scale by 1+100*eps to use low bits tii
 321         p0[i] = (0 * 10 + i * 1) * (1.0 + 100 * GMX_REAL_EPS);
 322         p1[i] = (1 * 10 + i * 1) * (1.0 + 100 * GMX_REAL_EPS);
 323         p2[i] = (2 * 10 + i * 1) * (1.0 + 100 * GMX_REAL_EPS);
 324         p3[i] = (3 * 10 + i * 1) * (1.0 + 100 * GMX_REAL_EPS);
 325     }
 326
 327     v0 = load4(p0);
 328     v1 = load4(p1);
 329     v2 = load4(p2);
 330     v3 = load4(p3);
 331
 332     transpose(&v0, &v1, &v2, &v3);
 333
 334     store4(p0, v0);
 335     store4(p1, v1);
 336     store4(p2, v2);
 337     store4(p3, v3);
 338
 339     for (i = 0; i < 4; i++)
 340     {
 341         EXPECT_REAL_EQ_TOL((i * 10 + 0) * (1.0 + 100 * GMX_REAL_EPS), p0[i], defaultRealTolerance());
 342         EXPECT_REAL_EQ_TOL((i * 10 + 1) * (1.0 + 100 * GMX_REAL_EPS), p1[i], defaultRealTolerance());
 343         EXPECT_REAL_EQ_TOL((i * 10 + 2) * (1.0 + 100 * GMX_REAL_EPS), p2[i], defaultRealTolerance());
 344         EXPECT_REAL_EQ_TOL((i * 10 + 3) * (1.0 + 100 * GMX_REAL_EPS), p3[i], defaultRealTolerance());
 345     }
 346 }
 347
 348 #    endif // GMX_SIMD4_HAVE_REAL
 349
 350 /*! \} */
 351 /*! \endcond */
 352
 353 } // namespace
 354 } // namespace test
 355 } // namespace gmx
 356
 357 #endif // GMX_SIMD