1 /* 2 * Copyright 2011 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkColorPriv.h" 9 #include "SkEndian.h" 10 #include "SkFloatBits.h" 11 #include "SkFloatingPoint.h" 12 #include "SkMathPriv.h" 13 #include "SkPoint.h" 14 #include "SkRandom.h" 15 #include "Test.h" 16 17 static void test_clz(skiatest::Reporter* reporter) { 18 REPORTER_ASSERT(reporter, 32 == SkCLZ(0)); 19 REPORTER_ASSERT(reporter, 31 == SkCLZ(1)); 20 REPORTER_ASSERT(reporter, 1 == SkCLZ(1 << 30)); 21 REPORTER_ASSERT(reporter, 0 == SkCLZ(~0U)); 22 23 SkRandom rand; 24 for (int i = 0; i < 1000; ++i) { 25 uint32_t mask = rand.nextU(); 26 // need to get some zeros for testing, but in some obscure way so the 27 // compiler won't "see" that, and work-around calling the functions. 28 mask >>= (mask & 31); 29 int intri = SkCLZ(mask); 30 int porta = SkCLZ_portable(mask); 31 REPORTER_ASSERT(reporter, intri == porta); 32 } 33 } 34 35 /////////////////////////////////////////////////////////////////////////////// 36 37 static float sk_fsel(float pred, float result_ge, float result_lt) { 38 return pred >= 0 ? result_ge : result_lt; 39 } 40 41 static float fast_floor(float x) { 42 // float big = sk_fsel(x, 0x1.0p+23, -0x1.0p+23); 43 float big = sk_fsel(x, (float)(1 << 23), -(float)(1 << 23)); 44 return (float)(x + big) - big; 45 } 46 47 static float std_floor(float x) { 48 return sk_float_floor(x); 49 } 50 51 static void test_floor_value(skiatest::Reporter* reporter, float value) { 52 float fast = fast_floor(value); 53 float std = std_floor(value); 54 REPORTER_ASSERT(reporter, std == fast); 55 // SkDebugf("value[%1.9f] std[%g] fast[%g] equal[%d]\n", 56 // value, std, fast, std == fast); 57 } 58 59 static void test_floor(skiatest::Reporter* reporter) { 60 static const float gVals[] = { 61 0, 1, 1.1f, 1.01f, 1.001f, 1.0001f, 1.00001f, 1.000001f, 1.0000001f 62 }; 63 64 for (size_t i = 0; i < SK_ARRAY_COUNT(gVals); ++i) { 65 test_floor_value(reporter, gVals[i]); 66 // test_floor_value(reporter, -gVals[i]); 67 } 68 } 69 70 /////////////////////////////////////////////////////////////////////////////// 71 72 // test that SkMul16ShiftRound and SkMulDiv255Round return the same result 73 static void test_muldivround(skiatest::Reporter* reporter) { 74 #if 0 75 // this "complete" test is too slow, so we test a random sampling of it 76 77 for (int a = 0; a <= 32767; ++a) { 78 for (int b = 0; b <= 32767; ++b) { 79 unsigned prod0 = SkMul16ShiftRound(a, b, 8); 80 unsigned prod1 = SkMulDiv255Round(a, b); 81 SkASSERT(prod0 == prod1); 82 } 83 } 84 #endif 85 86 SkRandom rand; 87 for (int i = 0; i < 10000; ++i) { 88 unsigned a = rand.nextU() & 0x7FFF; 89 unsigned b = rand.nextU() & 0x7FFF; 90 91 unsigned prod0 = SkMul16ShiftRound(a, b, 8); 92 unsigned prod1 = SkMulDiv255Round(a, b); 93 94 REPORTER_ASSERT(reporter, prod0 == prod1); 95 } 96 } 97 98 static float float_blend(int src, int dst, float unit) { 99 return dst + (src - dst) * unit; 100 } 101 102 static int blend31(int src, int dst, int a31) { 103 return dst + ((src - dst) * a31 * 2114 >> 16); 104 // return dst + ((src - dst) * a31 * 33 >> 10); 105 } 106 107 static int blend31_slow(int src, int dst, int a31) { 108 int prod = src * a31 + (31 - a31) * dst + 16; 109 prod = (prod + (prod >> 5)) >> 5; 110 return prod; 111 } 112 113 static int blend31_round(int src, int dst, int a31) { 114 int prod = (src - dst) * a31 + 16; 115 prod = (prod + (prod >> 5)) >> 5; 116 return dst + prod; 117 } 118 119 static int blend31_old(int src, int dst, int a31) { 120 a31 += a31 >> 4; 121 return dst + ((src - dst) * a31 >> 5); 122 } 123 124 // suppress unused code warning 125 static int (*blend_functions[])(int, int, int) = { 126 blend31, 127 blend31_slow, 128 blend31_round, 129 blend31_old 130 }; 131 132 static void test_blend31() { 133 int failed = 0; 134 int death = 0; 135 if (false) { // avoid bit rot, suppress warning 136 failed = (*blend_functions[0])(0,0,0); 137 } 138 for (int src = 0; src <= 255; src++) { 139 for (int dst = 0; dst <= 255; dst++) { 140 for (int a = 0; a <= 31; a++) { 141 // int r0 = blend31(src, dst, a); 142 // int r0 = blend31_round(src, dst, a); 143 // int r0 = blend31_old(src, dst, a); 144 int r0 = blend31_slow(src, dst, a); 145 146 float f = float_blend(src, dst, a / 31.f); 147 int r1 = (int)f; 148 int r2 = SkScalarRoundToInt(f); 149 150 if (r0 != r1 && r0 != r2) { 151 SkDebugf("src:%d dst:%d a:%d result:%d float:%g\n", 152 src, dst, a, r0, f); 153 failed += 1; 154 } 155 if (r0 > 255) { 156 death += 1; 157 SkDebugf("death src:%d dst:%d a:%d result:%d float:%g\n", 158 src, dst, a, r0, f); 159 } 160 } 161 } 162 } 163 SkDebugf("---- failed %d death %d\n", failed, death); 164 } 165 166 static void test_blend(skiatest::Reporter* reporter) { 167 for (int src = 0; src <= 255; src++) { 168 for (int dst = 0; dst <= 255; dst++) { 169 for (int a = 0; a <= 255; a++) { 170 int r0 = SkAlphaBlend255(src, dst, a); 171 float f1 = float_blend(src, dst, a / 255.f); 172 int r1 = SkScalarRoundToInt(f1); 173 174 if (r0 != r1) { 175 float diff = sk_float_abs(f1 - r1); 176 diff = sk_float_abs(diff - 0.5f); 177 if (diff > (1 / 255.f)) { 178 #ifdef SK_DEBUG 179 SkDebugf("src:%d dst:%d a:%d result:%d float:%g\n", 180 src, dst, a, r0, f1); 181 #endif 182 REPORTER_ASSERT(reporter, false); 183 } 184 } 185 } 186 } 187 } 188 } 189 190 static void check_length(skiatest::Reporter* reporter, 191 const SkPoint& p, SkScalar targetLen) { 192 float x = SkScalarToFloat(p.fX); 193 float y = SkScalarToFloat(p.fY); 194 float len = sk_float_sqrt(x*x + y*y); 195 196 len /= SkScalarToFloat(targetLen); 197 198 REPORTER_ASSERT(reporter, len > 0.999f && len < 1.001f); 199 } 200 201 static float nextFloat(SkRandom& rand) { 202 SkFloatIntUnion data; 203 data.fSignBitInt = rand.nextU(); 204 return data.fFloat; 205 } 206 207 /* returns true if a == b as resulting from (int)x. Since it is undefined 208 what to do if the float exceeds 2^32-1, we check for that explicitly. 209 */ 210 static bool equal_float_native_skia(float x, uint32_t ni, uint32_t si) { 211 if (!(x == x)) { // NAN 212 return ((int32_t)si) == SK_MaxS32 || ((int32_t)si) == SK_MinS32; 213 } 214 // for out of range, C is undefined, but skia always should return NaN32 215 if (x > SK_MaxS32) { 216 return ((int32_t)si) == SK_MaxS32; 217 } 218 if (x < -SK_MaxS32) { 219 return ((int32_t)si) == SK_MinS32; 220 } 221 return si == ni; 222 } 223 224 static void assert_float_equal(skiatest::Reporter* reporter, const char op[], 225 float x, uint32_t ni, uint32_t si) { 226 if (!equal_float_native_skia(x, ni, si)) { 227 ERRORF(reporter, "%s float %g bits %x native %x skia %x\n", 228 op, x, SkFloat2Bits(x), ni, si); 229 } 230 } 231 232 static void test_float_cast(skiatest::Reporter* reporter, float x) { 233 int ix = (int)x; 234 int iix = SkFloatToIntCast(x); 235 assert_float_equal(reporter, "cast", x, ix, iix); 236 } 237 238 static void test_float_floor(skiatest::Reporter* reporter, float x) { 239 int ix = (int)floor(x); 240 int iix = SkFloatToIntFloor(x); 241 assert_float_equal(reporter, "floor", x, ix, iix); 242 } 243 244 static void test_float_round(skiatest::Reporter* reporter, float x) { 245 double xx = x + 0.5; // need intermediate double to avoid temp loss 246 int ix = (int)floor(xx); 247 int iix = SkFloatToIntRound(x); 248 assert_float_equal(reporter, "round", x, ix, iix); 249 } 250 251 static void test_float_ceil(skiatest::Reporter* reporter, float x) { 252 int ix = (int)ceil(x); 253 int iix = SkFloatToIntCeil(x); 254 assert_float_equal(reporter, "ceil", x, ix, iix); 255 } 256 257 static void test_float_conversions(skiatest::Reporter* reporter, float x) { 258 test_float_cast(reporter, x); 259 test_float_floor(reporter, x); 260 test_float_round(reporter, x); 261 test_float_ceil(reporter, x); 262 } 263 264 static void test_int2float(skiatest::Reporter* reporter, int ival) { 265 float x0 = (float)ival; 266 float x1 = SkIntToFloatCast(ival); 267 REPORTER_ASSERT(reporter, x0 == x1); 268 } 269 270 static void unittest_fastfloat(skiatest::Reporter* reporter) { 271 SkRandom rand; 272 size_t i; 273 274 static const float gFloats[] = { 275 0.f, 1.f, 0.5f, 0.499999f, 0.5000001f, 1.f/3, 276 0.000000001f, 1000000000.f, // doesn't overflow 277 0.0000000001f, 10000000000.f // does overflow 278 }; 279 for (i = 0; i < SK_ARRAY_COUNT(gFloats); i++) { 280 test_float_conversions(reporter, gFloats[i]); 281 test_float_conversions(reporter, -gFloats[i]); 282 } 283 284 for (int outer = 0; outer < 100; outer++) { 285 rand.setSeed(outer); 286 for (i = 0; i < 100000; i++) { 287 float x = nextFloat(rand); 288 test_float_conversions(reporter, x); 289 } 290 291 test_int2float(reporter, 0); 292 test_int2float(reporter, 1); 293 test_int2float(reporter, -1); 294 for (i = 0; i < 100000; i++) { 295 // for now only test ints that are 24bits or less, since we don't 296 // round (down) large ints the same as IEEE... 297 int ival = rand.nextU() & 0xFFFFFF; 298 test_int2float(reporter, ival); 299 test_int2float(reporter, -ival); 300 } 301 } 302 } 303 304 static float make_zero() { 305 return sk_float_sin(0); 306 } 307 308 static void unittest_isfinite(skiatest::Reporter* reporter) { 309 float nan = sk_float_asin(2); 310 float inf = 1.0f / make_zero(); 311 float big = 3.40282e+038f; 312 313 REPORTER_ASSERT(reporter, !SkScalarIsNaN(inf)); 314 REPORTER_ASSERT(reporter, !SkScalarIsNaN(-inf)); 315 REPORTER_ASSERT(reporter, !SkScalarIsFinite(inf)); 316 REPORTER_ASSERT(reporter, !SkScalarIsFinite(-inf)); 317 318 REPORTER_ASSERT(reporter, SkScalarIsNaN(nan)); 319 REPORTER_ASSERT(reporter, !SkScalarIsNaN(big)); 320 REPORTER_ASSERT(reporter, !SkScalarIsNaN(-big)); 321 REPORTER_ASSERT(reporter, !SkScalarIsNaN(0)); 322 323 REPORTER_ASSERT(reporter, !SkScalarIsFinite(nan)); 324 REPORTER_ASSERT(reporter, SkScalarIsFinite(big)); 325 REPORTER_ASSERT(reporter, SkScalarIsFinite(-big)); 326 REPORTER_ASSERT(reporter, SkScalarIsFinite(0)); 327 } 328 329 static void test_muldiv255(skiatest::Reporter* reporter) { 330 for (int a = 0; a <= 255; a++) { 331 for (int b = 0; b <= 255; b++) { 332 int ab = a * b; 333 float s = ab / 255.0f; 334 int round = (int)floorf(s + 0.5f); 335 int trunc = (int)floorf(s); 336 337 int iround = SkMulDiv255Round(a, b); 338 int itrunc = SkMulDiv255Trunc(a, b); 339 340 REPORTER_ASSERT(reporter, iround == round); 341 REPORTER_ASSERT(reporter, itrunc == trunc); 342 343 REPORTER_ASSERT(reporter, itrunc <= iround); 344 REPORTER_ASSERT(reporter, iround <= a); 345 REPORTER_ASSERT(reporter, iround <= b); 346 } 347 } 348 } 349 350 static void test_muldiv255ceiling(skiatest::Reporter* reporter) { 351 for (int c = 0; c <= 255; c++) { 352 for (int a = 0; a <= 255; a++) { 353 int product = (c * a + 255); 354 int expected_ceiling = (product + (product >> 8)) >> 8; 355 int webkit_ceiling = (c * a + 254) / 255; 356 REPORTER_ASSERT(reporter, expected_ceiling == webkit_ceiling); 357 int skia_ceiling = SkMulDiv255Ceiling(c, a); 358 REPORTER_ASSERT(reporter, skia_ceiling == webkit_ceiling); 359 } 360 } 361 } 362 363 static void test_copysign(skiatest::Reporter* reporter) { 364 static const int32_t gTriples[] = { 365 // x, y, expected result 366 0, 0, 0, 367 0, 1, 0, 368 0, -1, 0, 369 1, 0, 1, 370 1, 1, 1, 371 1, -1, -1, 372 -1, 0, 1, 373 -1, 1, 1, 374 -1, -1, -1, 375 }; 376 for (size_t i = 0; i < SK_ARRAY_COUNT(gTriples); i += 3) { 377 REPORTER_ASSERT(reporter, 378 SkCopySign32(gTriples[i], gTriples[i+1]) == gTriples[i+2]); 379 float x = (float)gTriples[i]; 380 float y = (float)gTriples[i+1]; 381 float expected = (float)gTriples[i+2]; 382 REPORTER_ASSERT(reporter, sk_float_copysign(x, y) == expected); 383 } 384 385 SkRandom rand; 386 for (int j = 0; j < 1000; j++) { 387 int ix = rand.nextS(); 388 REPORTER_ASSERT(reporter, SkCopySign32(ix, ix) == ix); 389 REPORTER_ASSERT(reporter, SkCopySign32(ix, -ix) == -ix); 390 REPORTER_ASSERT(reporter, SkCopySign32(-ix, ix) == ix); 391 REPORTER_ASSERT(reporter, SkCopySign32(-ix, -ix) == -ix); 392 393 SkScalar sx = rand.nextSScalar1(); 394 REPORTER_ASSERT(reporter, SkScalarCopySign(sx, sx) == sx); 395 REPORTER_ASSERT(reporter, SkScalarCopySign(sx, -sx) == -sx); 396 REPORTER_ASSERT(reporter, SkScalarCopySign(-sx, sx) == sx); 397 REPORTER_ASSERT(reporter, SkScalarCopySign(-sx, -sx) == -sx); 398 } 399 } 400 401 DEF_TEST(Math, reporter) { 402 int i; 403 SkRandom rand; 404 405 // these should assert 406 #if 0 407 SkToS8(128); 408 SkToS8(-129); 409 SkToU8(256); 410 SkToU8(-5); 411 412 SkToS16(32768); 413 SkToS16(-32769); 414 SkToU16(65536); 415 SkToU16(-5); 416 417 if (sizeof(size_t) > 4) { 418 SkToS32(4*1024*1024); 419 SkToS32(-4*1024*1024); 420 SkToU32(5*1024*1024); 421 SkToU32(-5); 422 } 423 #endif 424 425 test_muldiv255(reporter); 426 test_muldiv255ceiling(reporter); 427 test_copysign(reporter); 428 429 { 430 SkScalar x = SK_ScalarNaN; 431 REPORTER_ASSERT(reporter, SkScalarIsNaN(x)); 432 } 433 434 for (i = 0; i < 1000; i++) { 435 int value = rand.nextS16(); 436 int max = rand.nextU16(); 437 438 int clamp = SkClampMax(value, max); 439 int clamp2 = value < 0 ? 0 : (value > max ? max : value); 440 REPORTER_ASSERT(reporter, clamp == clamp2); 441 } 442 443 for (i = 0; i < 10000; i++) { 444 SkPoint p; 445 446 // These random values are being treated as 32-bit-patterns, not as 447 // ints; calling SkIntToScalar() here produces crashes. 448 p.setLength((SkScalar) rand.nextS(), 449 (SkScalar) rand.nextS(), 450 SK_Scalar1); 451 check_length(reporter, p, SK_Scalar1); 452 p.setLength((SkScalar) (rand.nextS() >> 13), 453 (SkScalar) (rand.nextS() >> 13), 454 SK_Scalar1); 455 check_length(reporter, p, SK_Scalar1); 456 } 457 458 { 459 SkFixed result = SkFixedDiv(100, 100); 460 REPORTER_ASSERT(reporter, result == SK_Fixed1); 461 result = SkFixedDiv(1, SK_Fixed1); 462 REPORTER_ASSERT(reporter, result == 1); 463 } 464 465 unittest_fastfloat(reporter); 466 unittest_isfinite(reporter); 467 468 for (i = 0; i < 10000; i++) { 469 SkFixed numer = rand.nextS(); 470 SkFixed denom = rand.nextS(); 471 SkFixed result = SkFixedDiv(numer, denom); 472 int64_t check = ((int64_t)numer << 16) / denom; 473 474 (void)SkCLZ(numer); 475 (void)SkCLZ(denom); 476 477 REPORTER_ASSERT(reporter, result != (SkFixed)SK_NaN32); 478 if (check > SK_MaxS32) { 479 check = SK_MaxS32; 480 } else if (check < -SK_MaxS32) { 481 check = SK_MinS32; 482 } 483 REPORTER_ASSERT(reporter, result == (int32_t)check); 484 } 485 486 test_blend(reporter); 487 488 if (false) test_floor(reporter); 489 490 // disable for now 491 if (false) test_blend31(); // avoid bit rot, suppress warning 492 493 test_muldivround(reporter); 494 test_clz(reporter); 495 } 496 497 template <typename T> struct PairRec { 498 T fYin; 499 T fYang; 500 }; 501 502 DEF_TEST(TestEndian, reporter) { 503 static const PairRec<uint16_t> g16[] = { 504 { 0x0, 0x0 }, 505 { 0xFFFF, 0xFFFF }, 506 { 0x1122, 0x2211 }, 507 }; 508 static const PairRec<uint32_t> g32[] = { 509 { 0x0, 0x0 }, 510 { 0xFFFFFFFF, 0xFFFFFFFF }, 511 { 0x11223344, 0x44332211 }, 512 }; 513 static const PairRec<uint64_t> g64[] = { 514 { 0x0, 0x0 }, 515 { 0xFFFFFFFFFFFFFFFFULL, 0xFFFFFFFFFFFFFFFFULL }, 516 { 0x1122334455667788ULL, 0x8877665544332211ULL }, 517 }; 518 519 REPORTER_ASSERT(reporter, 0x1122 == SkTEndianSwap16<0x2211>::value); 520 REPORTER_ASSERT(reporter, 0x11223344 == SkTEndianSwap32<0x44332211>::value); 521 REPORTER_ASSERT(reporter, 0x1122334455667788ULL == SkTEndianSwap64<0x8877665544332211ULL>::value); 522 523 for (size_t i = 0; i < SK_ARRAY_COUNT(g16); ++i) { 524 REPORTER_ASSERT(reporter, g16[i].fYang == SkEndianSwap16(g16[i].fYin)); 525 } 526 for (size_t i = 0; i < SK_ARRAY_COUNT(g32); ++i) { 527 REPORTER_ASSERT(reporter, g32[i].fYang == SkEndianSwap32(g32[i].fYin)); 528 } 529 for (size_t i = 0; i < SK_ARRAY_COUNT(g64); ++i) { 530 REPORTER_ASSERT(reporter, g64[i].fYang == SkEndianSwap64(g64[i].fYin)); 531 } 532 } 533 534 template <typename T> 535 static void test_divmod(skiatest::Reporter* r) { 536 const struct { 537 T numer; 538 T denom; 539 } kEdgeCases[] = { 540 {(T)17, (T)17}, 541 {(T)17, (T)4}, 542 {(T)0, (T)17}, 543 // For unsigned T these negatives are just some large numbers. Doesn't hurt to test them. 544 {(T)-17, (T)-17}, 545 {(T)-17, (T)4}, 546 {(T)17, (T)-4}, 547 {(T)-17, (T)-4}, 548 }; 549 550 for (size_t i = 0; i < SK_ARRAY_COUNT(kEdgeCases); i++) { 551 const T numer = kEdgeCases[i].numer; 552 const T denom = kEdgeCases[i].denom; 553 T div, mod; 554 SkTDivMod(numer, denom, &div, &mod); 555 REPORTER_ASSERT(r, numer/denom == div); 556 REPORTER_ASSERT(r, numer%denom == mod); 557 } 558 559 SkRandom rand; 560 for (size_t i = 0; i < 10000; i++) { 561 const T numer = (T)rand.nextS(); 562 T denom = 0; 563 while (0 == denom) { 564 denom = (T)rand.nextS(); 565 } 566 T div, mod; 567 SkTDivMod(numer, denom, &div, &mod); 568 REPORTER_ASSERT(r, numer/denom == div); 569 REPORTER_ASSERT(r, numer%denom == mod); 570 } 571 } 572 573 DEF_TEST(divmod_u8, r) { 574 test_divmod<uint8_t>(r); 575 } 576 577 DEF_TEST(divmod_u16, r) { 578 test_divmod<uint16_t>(r); 579 } 580 581 DEF_TEST(divmod_u32, r) { 582 test_divmod<uint32_t>(r); 583 } 584 585 DEF_TEST(divmod_u64, r) { 586 test_divmod<uint64_t>(r); 587 } 588 589 DEF_TEST(divmod_s8, r) { 590 test_divmod<int8_t>(r); 591 } 592 593 DEF_TEST(divmod_s16, r) { 594 test_divmod<int16_t>(r); 595 } 596 597 DEF_TEST(divmod_s32, r) { 598 test_divmod<int32_t>(r); 599 } 600 601 DEF_TEST(divmod_s64, r) { 602 test_divmod<int64_t>(r); 603 } 604
