1 //===- unittests/Support/MathExtrasTest.cpp - math utils tests ------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "llvm/Support/MathExtras.h" 10 #include "gtest/gtest.h" 11 12 using namespace llvm; 13 14 namespace { 15 16 TEST(MathExtras, countTrailingZeros) { 17 uint8_t Z8 = 0; 18 uint16_t Z16 = 0; 19 uint32_t Z32 = 0; 20 uint64_t Z64 = 0; 21 EXPECT_EQ(8u, countTrailingZeros(Z8)); 22 EXPECT_EQ(16u, countTrailingZeros(Z16)); 23 EXPECT_EQ(32u, countTrailingZeros(Z32)); 24 EXPECT_EQ(64u, countTrailingZeros(Z64)); 25 26 uint8_t NZ8 = 42; 27 uint16_t NZ16 = 42; 28 uint32_t NZ32 = 42; 29 uint64_t NZ64 = 42; 30 EXPECT_EQ(1u, countTrailingZeros(NZ8)); 31 EXPECT_EQ(1u, countTrailingZeros(NZ16)); 32 EXPECT_EQ(1u, countTrailingZeros(NZ32)); 33 EXPECT_EQ(1u, countTrailingZeros(NZ64)); 34 } 35 36 TEST(MathExtras, countLeadingZeros) { 37 uint8_t Z8 = 0; 38 uint16_t Z16 = 0; 39 uint32_t Z32 = 0; 40 uint64_t Z64 = 0; 41 EXPECT_EQ(8u, countLeadingZeros(Z8)); 42 EXPECT_EQ(16u, countLeadingZeros(Z16)); 43 EXPECT_EQ(32u, countLeadingZeros(Z32)); 44 EXPECT_EQ(64u, countLeadingZeros(Z64)); 45 46 uint8_t NZ8 = 42; 47 uint16_t NZ16 = 42; 48 uint32_t NZ32 = 42; 49 uint64_t NZ64 = 42; 50 EXPECT_EQ(2u, countLeadingZeros(NZ8)); 51 EXPECT_EQ(10u, countLeadingZeros(NZ16)); 52 EXPECT_EQ(26u, countLeadingZeros(NZ32)); 53 EXPECT_EQ(58u, countLeadingZeros(NZ64)); 54 55 EXPECT_EQ(8u, countLeadingZeros(0x00F000FFu)); 56 EXPECT_EQ(8u, countLeadingZeros(0x00F12345u)); 57 for (unsigned i = 0; i <= 30; ++i) { 58 EXPECT_EQ(31 - i, countLeadingZeros(1u << i)); 59 } 60 61 EXPECT_EQ(8u, countLeadingZeros(0x00F1234500F12345ULL)); 62 EXPECT_EQ(1u, countLeadingZeros(1ULL << 62)); 63 for (unsigned i = 0; i <= 62; ++i) { 64 EXPECT_EQ(63 - i, countLeadingZeros(1ULL << i)); 65 } 66 } 67 68 TEST(MathExtras, onesMask) { 69 EXPECT_EQ(0U, maskLeadingOnes<uint8_t>(0)); 70 EXPECT_EQ(0U, maskTrailingOnes<uint8_t>(0)); 71 EXPECT_EQ(0U, maskLeadingOnes<uint16_t>(0)); 72 EXPECT_EQ(0U, maskTrailingOnes<uint16_t>(0)); 73 EXPECT_EQ(0U, maskLeadingOnes<uint32_t>(0)); 74 EXPECT_EQ(0U, maskTrailingOnes<uint32_t>(0)); 75 EXPECT_EQ(0U, maskLeadingOnes<uint64_t>(0)); 76 EXPECT_EQ(0U, maskTrailingOnes<uint64_t>(0)); 77 78 EXPECT_EQ(0x00000003U, maskTrailingOnes<uint32_t>(2U)); 79 EXPECT_EQ(0xC0000000U, maskLeadingOnes<uint32_t>(2U)); 80 81 EXPECT_EQ(0x000007FFU, maskTrailingOnes<uint32_t>(11U)); 82 EXPECT_EQ(0xFFE00000U, maskLeadingOnes<uint32_t>(11U)); 83 84 EXPECT_EQ(0xFFFFFFFFU, maskTrailingOnes<uint32_t>(32U)); 85 EXPECT_EQ(0xFFFFFFFFU, maskLeadingOnes<uint32_t>(32U)); 86 EXPECT_EQ(0xFFFFFFFFFFFFFFFFULL, maskTrailingOnes<uint64_t>(64U)); 87 EXPECT_EQ(0xFFFFFFFFFFFFFFFFULL, maskLeadingOnes<uint64_t>(64U)); 88 89 EXPECT_EQ(0x0000FFFFFFFFFFFFULL, maskTrailingOnes<uint64_t>(48U)); 90 EXPECT_EQ(0xFFFFFFFFFFFF0000ULL, maskLeadingOnes<uint64_t>(48U)); 91 } 92 93 TEST(MathExtras, findFirstSet) { 94 uint8_t Z8 = 0; 95 uint16_t Z16 = 0; 96 uint32_t Z32 = 0; 97 uint64_t Z64 = 0; 98 EXPECT_EQ(0xFFULL, findFirstSet(Z8)); 99 EXPECT_EQ(0xFFFFULL, findFirstSet(Z16)); 100 EXPECT_EQ(0xFFFFFFFFULL, findFirstSet(Z32)); 101 EXPECT_EQ(0xFFFFFFFFFFFFFFFFULL, findFirstSet(Z64)); 102 103 uint8_t NZ8 = 42; 104 uint16_t NZ16 = 42; 105 uint32_t NZ32 = 42; 106 uint64_t NZ64 = 42; 107 EXPECT_EQ(1u, findFirstSet(NZ8)); 108 EXPECT_EQ(1u, findFirstSet(NZ16)); 109 EXPECT_EQ(1u, findFirstSet(NZ32)); 110 EXPECT_EQ(1u, findFirstSet(NZ64)); 111 } 112 113 TEST(MathExtras, findLastSet) { 114 uint8_t Z8 = 0; 115 uint16_t Z16 = 0; 116 uint32_t Z32 = 0; 117 uint64_t Z64 = 0; 118 EXPECT_EQ(0xFFULL, findLastSet(Z8)); 119 EXPECT_EQ(0xFFFFULL, findLastSet(Z16)); 120 EXPECT_EQ(0xFFFFFFFFULL, findLastSet(Z32)); 121 EXPECT_EQ(0xFFFFFFFFFFFFFFFFULL, findLastSet(Z64)); 122 123 uint8_t NZ8 = 42; 124 uint16_t NZ16 = 42; 125 uint32_t NZ32 = 42; 126 uint64_t NZ64 = 42; 127 EXPECT_EQ(5u, findLastSet(NZ8)); 128 EXPECT_EQ(5u, findLastSet(NZ16)); 129 EXPECT_EQ(5u, findLastSet(NZ32)); 130 EXPECT_EQ(5u, findLastSet(NZ64)); 131 } 132 133 TEST(MathExtras, isIntN) { 134 EXPECT_TRUE(isIntN(16, 32767)); 135 EXPECT_FALSE(isIntN(16, 32768)); 136 } 137 138 TEST(MathExtras, isUIntN) { 139 EXPECT_TRUE(isUIntN(16, 65535)); 140 EXPECT_FALSE(isUIntN(16, 65536)); 141 EXPECT_TRUE(isUIntN(1, 0)); 142 EXPECT_TRUE(isUIntN(6, 63)); 143 } 144 145 TEST(MathExtras, maxIntN) { 146 EXPECT_EQ(32767, maxIntN(16)); 147 EXPECT_EQ(2147483647, maxIntN(32)); 148 EXPECT_EQ(std::numeric_limits<int32_t>::max(), maxIntN(32)); 149 EXPECT_EQ(std::numeric_limits<int64_t>::max(), maxIntN(64)); 150 } 151 152 TEST(MathExtras, minIntN) { 153 EXPECT_EQ(-32768LL, minIntN(16)); 154 EXPECT_EQ(-64LL, minIntN(7)); 155 EXPECT_EQ(std::numeric_limits<int32_t>::min(), minIntN(32)); 156 EXPECT_EQ(std::numeric_limits<int64_t>::min(), minIntN(64)); 157 } 158 159 TEST(MathExtras, maxUIntN) { 160 EXPECT_EQ(0xffffULL, maxUIntN(16)); 161 EXPECT_EQ(0xffffffffULL, maxUIntN(32)); 162 EXPECT_EQ(0xffffffffffffffffULL, maxUIntN(64)); 163 EXPECT_EQ(1ULL, maxUIntN(1)); 164 EXPECT_EQ(0x0fULL, maxUIntN(4)); 165 } 166 167 TEST(MathExtras, reverseBits) { 168 uint8_t NZ8 = 42; 169 uint16_t NZ16 = 42; 170 uint32_t NZ32 = 42; 171 uint64_t NZ64 = 42; 172 EXPECT_EQ(0x54ULL, reverseBits(NZ8)); 173 EXPECT_EQ(0x5400ULL, reverseBits(NZ16)); 174 EXPECT_EQ(0x54000000ULL, reverseBits(NZ32)); 175 EXPECT_EQ(0x5400000000000000ULL, reverseBits(NZ64)); 176 } 177 178 TEST(MathExtras, isPowerOf2_32) { 179 EXPECT_FALSE(isPowerOf2_32(0)); 180 EXPECT_TRUE(isPowerOf2_32(1 << 6)); 181 EXPECT_TRUE(isPowerOf2_32(1 << 12)); 182 EXPECT_FALSE(isPowerOf2_32((1 << 19) + 3)); 183 EXPECT_FALSE(isPowerOf2_32(0xABCDEF0)); 184 } 185 186 TEST(MathExtras, isPowerOf2_64) { 187 EXPECT_FALSE(isPowerOf2_64(0)); 188 EXPECT_TRUE(isPowerOf2_64(1LL << 46)); 189 EXPECT_TRUE(isPowerOf2_64(1LL << 12)); 190 EXPECT_FALSE(isPowerOf2_64((1LL << 53) + 3)); 191 EXPECT_FALSE(isPowerOf2_64(0xABCDEF0ABCDEF0LL)); 192 } 193 194 TEST(MathExtras, PowerOf2Ceil) { 195 EXPECT_EQ(0U, PowerOf2Ceil(0U)); 196 EXPECT_EQ(8U, PowerOf2Ceil(8U)); 197 EXPECT_EQ(8U, PowerOf2Ceil(7U)); 198 } 199 200 TEST(MathExtras, PowerOf2Floor) { 201 EXPECT_EQ(0U, PowerOf2Floor(0U)); 202 EXPECT_EQ(8U, PowerOf2Floor(8U)); 203 EXPECT_EQ(4U, PowerOf2Floor(7U)); 204 } 205 206 TEST(MathExtras, CTLog2) { 207 EXPECT_EQ(CTLog2<1ULL << 0>(), 0U); 208 EXPECT_EQ(CTLog2<1ULL << 1>(), 1U); 209 EXPECT_EQ(CTLog2<1ULL << 2>(), 2U); 210 EXPECT_EQ(CTLog2<1ULL << 3>(), 3U); 211 EXPECT_EQ(CTLog2<1ULL << 4>(), 4U); 212 EXPECT_EQ(CTLog2<1ULL << 5>(), 5U); 213 EXPECT_EQ(CTLog2<1ULL << 6>(), 6U); 214 EXPECT_EQ(CTLog2<1ULL << 7>(), 7U); 215 EXPECT_EQ(CTLog2<1ULL << 8>(), 8U); 216 EXPECT_EQ(CTLog2<1ULL << 9>(), 9U); 217 EXPECT_EQ(CTLog2<1ULL << 10>(), 10U); 218 EXPECT_EQ(CTLog2<1ULL << 11>(), 11U); 219 EXPECT_EQ(CTLog2<1ULL << 12>(), 12U); 220 EXPECT_EQ(CTLog2<1ULL << 13>(), 13U); 221 EXPECT_EQ(CTLog2<1ULL << 14>(), 14U); 222 EXPECT_EQ(CTLog2<1ULL << 15>(), 15U); 223 } 224 225 TEST(MathExtras, ByteSwap_32) { 226 EXPECT_EQ(0x44332211u, ByteSwap_32(0x11223344)); 227 EXPECT_EQ(0xDDCCBBAAu, ByteSwap_32(0xAABBCCDD)); 228 } 229 230 TEST(MathExtras, ByteSwap_64) { 231 EXPECT_EQ(0x8877665544332211ULL, ByteSwap_64(0x1122334455667788LL)); 232 EXPECT_EQ(0x1100FFEEDDCCBBAAULL, ByteSwap_64(0xAABBCCDDEEFF0011LL)); 233 } 234 235 TEST(MathExtras, countLeadingOnes) { 236 for (int i = 30; i >= 0; --i) { 237 // Start with all ones and unset some bit. 238 EXPECT_EQ(31u - i, countLeadingOnes(0xFFFFFFFF ^ (1 << i))); 239 } 240 for (int i = 62; i >= 0; --i) { 241 // Start with all ones and unset some bit. 242 EXPECT_EQ(63u - i, countLeadingOnes(0xFFFFFFFFFFFFFFFFULL ^ (1LL << i))); 243 } 244 for (int i = 30; i >= 0; --i) { 245 // Start with all ones and unset some bit. 246 EXPECT_EQ(31u - i, countLeadingOnes(0xFFFFFFFF ^ (1 << i))); 247 } 248 } 249 250 TEST(MathExtras, FloatBits) { 251 static const float kValue = 5632.34f; 252 EXPECT_FLOAT_EQ(kValue, BitsToFloat(FloatToBits(kValue))); 253 } 254 255 TEST(MathExtras, DoubleBits) { 256 static const double kValue = 87987234.983498; 257 EXPECT_DOUBLE_EQ(kValue, BitsToDouble(DoubleToBits(kValue))); 258 } 259 260 TEST(MathExtras, MinAlign) { 261 EXPECT_EQ(1u, MinAlign(2, 3)); 262 EXPECT_EQ(2u, MinAlign(2, 4)); 263 EXPECT_EQ(1u, MinAlign(17, 64)); 264 EXPECT_EQ(256u, MinAlign(256, 512)); 265 } 266 267 TEST(MathExtras, NextPowerOf2) { 268 EXPECT_EQ(4u, NextPowerOf2(3)); 269 EXPECT_EQ(16u, NextPowerOf2(15)); 270 EXPECT_EQ(256u, NextPowerOf2(128)); 271 } 272 273 TEST(MathExtras, alignTo) { 274 EXPECT_EQ(8u, alignTo(5, 8)); 275 EXPECT_EQ(24u, alignTo(17, 8)); 276 EXPECT_EQ(0u, alignTo(~0LL, 8)); 277 278 EXPECT_EQ(7u, alignTo(5, 8, 7)); 279 EXPECT_EQ(17u, alignTo(17, 8, 1)); 280 EXPECT_EQ(3u, alignTo(~0LL, 8, 3)); 281 EXPECT_EQ(552u, alignTo(321, 255, 42)); 282 } 283 284 template<typename T> 285 void SaturatingAddTestHelper() 286 { 287 const T Max = std::numeric_limits<T>::max(); 288 bool ResultOverflowed; 289 290 EXPECT_EQ(T(3), SaturatingAdd(T(1), T(2))); 291 EXPECT_EQ(T(3), SaturatingAdd(T(1), T(2), &ResultOverflowed)); 292 EXPECT_FALSE(ResultOverflowed); 293 294 EXPECT_EQ(Max, SaturatingAdd(Max, T(1))); 295 EXPECT_EQ(Max, SaturatingAdd(Max, T(1), &ResultOverflowed)); 296 EXPECT_TRUE(ResultOverflowed); 297 298 EXPECT_EQ(Max, SaturatingAdd(T(1), T(Max - 1))); 299 EXPECT_EQ(Max, SaturatingAdd(T(1), T(Max - 1), &ResultOverflowed)); 300 EXPECT_FALSE(ResultOverflowed); 301 302 EXPECT_EQ(Max, SaturatingAdd(T(1), Max)); 303 EXPECT_EQ(Max, SaturatingAdd(T(1), Max, &ResultOverflowed)); 304 EXPECT_TRUE(ResultOverflowed); 305 306 EXPECT_EQ(Max, SaturatingAdd(Max, Max)); 307 EXPECT_EQ(Max, SaturatingAdd(Max, Max, &ResultOverflowed)); 308 EXPECT_TRUE(ResultOverflowed); 309 } 310 311 TEST(MathExtras, SaturatingAdd) { 312 SaturatingAddTestHelper<uint8_t>(); 313 SaturatingAddTestHelper<uint16_t>(); 314 SaturatingAddTestHelper<uint32_t>(); 315 SaturatingAddTestHelper<uint64_t>(); 316 } 317 318 template<typename T> 319 void SaturatingMultiplyTestHelper() 320 { 321 const T Max = std::numeric_limits<T>::max(); 322 bool ResultOverflowed; 323 324 // Test basic multiplication. 325 EXPECT_EQ(T(6), SaturatingMultiply(T(2), T(3))); 326 EXPECT_EQ(T(6), SaturatingMultiply(T(2), T(3), &ResultOverflowed)); 327 EXPECT_FALSE(ResultOverflowed); 328 329 EXPECT_EQ(T(6), SaturatingMultiply(T(3), T(2))); 330 EXPECT_EQ(T(6), SaturatingMultiply(T(3), T(2), &ResultOverflowed)); 331 EXPECT_FALSE(ResultOverflowed); 332 333 // Test multiplication by zero. 334 EXPECT_EQ(T(0), SaturatingMultiply(T(0), T(0))); 335 EXPECT_EQ(T(0), SaturatingMultiply(T(0), T(0), &ResultOverflowed)); 336 EXPECT_FALSE(ResultOverflowed); 337 338 EXPECT_EQ(T(0), SaturatingMultiply(T(1), T(0))); 339 EXPECT_EQ(T(0), SaturatingMultiply(T(1), T(0), &ResultOverflowed)); 340 EXPECT_FALSE(ResultOverflowed); 341 342 EXPECT_EQ(T(0), SaturatingMultiply(T(0), T(1))); 343 EXPECT_EQ(T(0), SaturatingMultiply(T(0), T(1), &ResultOverflowed)); 344 EXPECT_FALSE(ResultOverflowed); 345 346 EXPECT_EQ(T(0), SaturatingMultiply(Max, T(0))); 347 EXPECT_EQ(T(0), SaturatingMultiply(Max, T(0), &ResultOverflowed)); 348 EXPECT_FALSE(ResultOverflowed); 349 350 EXPECT_EQ(T(0), SaturatingMultiply(T(0), Max)); 351 EXPECT_EQ(T(0), SaturatingMultiply(T(0), Max, &ResultOverflowed)); 352 EXPECT_FALSE(ResultOverflowed); 353 354 // Test multiplication by maximum value. 355 EXPECT_EQ(Max, SaturatingMultiply(Max, T(2))); 356 EXPECT_EQ(Max, SaturatingMultiply(Max, T(2), &ResultOverflowed)); 357 EXPECT_TRUE(ResultOverflowed); 358 359 EXPECT_EQ(Max, SaturatingMultiply(T(2), Max)); 360 EXPECT_EQ(Max, SaturatingMultiply(T(2), Max, &ResultOverflowed)); 361 EXPECT_TRUE(ResultOverflowed); 362 363 EXPECT_EQ(Max, SaturatingMultiply(Max, Max)); 364 EXPECT_EQ(Max, SaturatingMultiply(Max, Max, &ResultOverflowed)); 365 EXPECT_TRUE(ResultOverflowed); 366 367 // Test interesting boundary conditions for algorithm - 368 // ((1 << A) - 1) * ((1 << B) + K) for K in [-1, 0, 1] 369 // and A + B == std::numeric_limits<T>::digits. 370 // We expect overflow iff A > B and K = 1. 371 const int Digits = std::numeric_limits<T>::digits; 372 for (int A = 1, B = Digits - 1; B >= 1; ++A, --B) { 373 for (int K = -1; K <= 1; ++K) { 374 T X = (T(1) << A) - T(1); 375 T Y = (T(1) << B) + K; 376 bool OverflowExpected = A > B && K == 1; 377 378 if(OverflowExpected) { 379 EXPECT_EQ(Max, SaturatingMultiply(X, Y)); 380 EXPECT_EQ(Max, SaturatingMultiply(X, Y, &ResultOverflowed)); 381 EXPECT_TRUE(ResultOverflowed); 382 } else { 383 EXPECT_EQ(X * Y, SaturatingMultiply(X, Y)); 384 EXPECT_EQ(X * Y, SaturatingMultiply(X, Y, &ResultOverflowed)); 385 EXPECT_FALSE(ResultOverflowed); 386 } 387 } 388 } 389 } 390 391 TEST(MathExtras, SaturatingMultiply) { 392 SaturatingMultiplyTestHelper<uint8_t>(); 393 SaturatingMultiplyTestHelper<uint16_t>(); 394 SaturatingMultiplyTestHelper<uint32_t>(); 395 SaturatingMultiplyTestHelper<uint64_t>(); 396 } 397 398 template<typename T> 399 void SaturatingMultiplyAddTestHelper() 400 { 401 const T Max = std::numeric_limits<T>::max(); 402 bool ResultOverflowed; 403 404 // Test basic multiply-add. 405 EXPECT_EQ(T(16), SaturatingMultiplyAdd(T(2), T(3), T(10))); 406 EXPECT_EQ(T(16), SaturatingMultiplyAdd(T(2), T(3), T(10), &ResultOverflowed)); 407 EXPECT_FALSE(ResultOverflowed); 408 409 // Test multiply overflows, add doesn't overflow 410 EXPECT_EQ(Max, SaturatingMultiplyAdd(Max, Max, T(0), &ResultOverflowed)); 411 EXPECT_TRUE(ResultOverflowed); 412 413 // Test multiply doesn't overflow, add overflows 414 EXPECT_EQ(Max, SaturatingMultiplyAdd(T(1), T(1), Max, &ResultOverflowed)); 415 EXPECT_TRUE(ResultOverflowed); 416 417 // Test multiply-add with Max as operand 418 EXPECT_EQ(Max, SaturatingMultiplyAdd(T(1), T(1), Max, &ResultOverflowed)); 419 EXPECT_TRUE(ResultOverflowed); 420 421 EXPECT_EQ(Max, SaturatingMultiplyAdd(T(1), Max, T(1), &ResultOverflowed)); 422 EXPECT_TRUE(ResultOverflowed); 423 424 EXPECT_EQ(Max, SaturatingMultiplyAdd(Max, Max, T(1), &ResultOverflowed)); 425 EXPECT_TRUE(ResultOverflowed); 426 427 EXPECT_EQ(Max, SaturatingMultiplyAdd(Max, Max, Max, &ResultOverflowed)); 428 EXPECT_TRUE(ResultOverflowed); 429 430 // Test multiply-add with 0 as operand 431 EXPECT_EQ(T(1), SaturatingMultiplyAdd(T(1), T(1), T(0), &ResultOverflowed)); 432 EXPECT_FALSE(ResultOverflowed); 433 434 EXPECT_EQ(T(1), SaturatingMultiplyAdd(T(1), T(0), T(1), &ResultOverflowed)); 435 EXPECT_FALSE(ResultOverflowed); 436 437 EXPECT_EQ(T(1), SaturatingMultiplyAdd(T(0), T(0), T(1), &ResultOverflowed)); 438 EXPECT_FALSE(ResultOverflowed); 439 440 EXPECT_EQ(T(0), SaturatingMultiplyAdd(T(0), T(0), T(0), &ResultOverflowed)); 441 EXPECT_FALSE(ResultOverflowed); 442 443 } 444 445 TEST(MathExtras, SaturatingMultiplyAdd) { 446 SaturatingMultiplyAddTestHelper<uint8_t>(); 447 SaturatingMultiplyAddTestHelper<uint16_t>(); 448 SaturatingMultiplyAddTestHelper<uint32_t>(); 449 SaturatingMultiplyAddTestHelper<uint64_t>(); 450 } 451 452 TEST(MathExtras, IsShiftedUInt) { 453 EXPECT_TRUE((isShiftedUInt<1, 0>(0))); 454 EXPECT_TRUE((isShiftedUInt<1, 0>(1))); 455 EXPECT_FALSE((isShiftedUInt<1, 0>(2))); 456 EXPECT_FALSE((isShiftedUInt<1, 0>(3))); 457 EXPECT_FALSE((isShiftedUInt<1, 0>(0x8000000000000000))); 458 EXPECT_TRUE((isShiftedUInt<1, 63>(0x8000000000000000))); 459 EXPECT_TRUE((isShiftedUInt<2, 62>(0xC000000000000000))); 460 EXPECT_FALSE((isShiftedUInt<2, 62>(0xE000000000000000))); 461 462 // 0x201 is ten bits long and has a 1 in the MSB and LSB. 463 EXPECT_TRUE((isShiftedUInt<10, 5>(uint64_t(0x201) << 5))); 464 EXPECT_FALSE((isShiftedUInt<10, 5>(uint64_t(0x201) << 4))); 465 EXPECT_FALSE((isShiftedUInt<10, 5>(uint64_t(0x201) << 6))); 466 } 467 468 TEST(MathExtras, IsShiftedInt) { 469 EXPECT_TRUE((isShiftedInt<1, 0>(0))); 470 EXPECT_TRUE((isShiftedInt<1, 0>(-1))); 471 EXPECT_FALSE((isShiftedInt<1, 0>(2))); 472 EXPECT_FALSE((isShiftedInt<1, 0>(3))); 473 EXPECT_FALSE((isShiftedInt<1, 0>(0x8000000000000000))); 474 EXPECT_TRUE((isShiftedInt<1, 63>(0x8000000000000000))); 475 EXPECT_TRUE((isShiftedInt<2, 62>(0xC000000000000000))); 476 EXPECT_FALSE((isShiftedInt<2, 62>(0xE000000000000000))); 477 478 // 0x201 is ten bits long and has a 1 in the MSB and LSB. 479 EXPECT_TRUE((isShiftedInt<11, 5>(int64_t(0x201) << 5))); 480 EXPECT_FALSE((isShiftedInt<11, 5>(int64_t(0x201) << 3))); 481 EXPECT_FALSE((isShiftedInt<11, 5>(int64_t(0x201) << 6))); 482 EXPECT_TRUE((isShiftedInt<11, 5>(-(int64_t(0x201) << 5)))); 483 EXPECT_FALSE((isShiftedInt<11, 5>(-(int64_t(0x201) << 3)))); 484 EXPECT_FALSE((isShiftedInt<11, 5>(-(int64_t(0x201) << 6)))); 485 486 EXPECT_TRUE((isShiftedInt<6, 10>(-(int64_t(1) << 15)))); 487 EXPECT_FALSE((isShiftedInt<6, 10>(int64_t(1) << 15))); 488 } 489 490 template <typename T> 491 class OverflowTest : public ::testing::Test { }; 492 493 using OverflowTestTypes = ::testing::Types<signed char, short, int, long, 494 long long>; 495 496 TYPED_TEST_CASE(OverflowTest, OverflowTestTypes); 497 498 TYPED_TEST(OverflowTest, AddNoOverflow) { 499 TypeParam Result; 500 EXPECT_FALSE(AddOverflow<TypeParam>(1, 2, Result)); 501 EXPECT_EQ(Result, TypeParam(3)); 502 } 503 504 TYPED_TEST(OverflowTest, AddOverflowToNegative) { 505 TypeParam Result; 506 auto MaxValue = std::numeric_limits<TypeParam>::max(); 507 EXPECT_TRUE(AddOverflow<TypeParam>(MaxValue, MaxValue, Result)); 508 EXPECT_EQ(Result, TypeParam(-2)); 509 } 510 511 TYPED_TEST(OverflowTest, AddOverflowToMin) { 512 TypeParam Result; 513 auto MaxValue = std::numeric_limits<TypeParam>::max(); 514 EXPECT_TRUE(AddOverflow<TypeParam>(MaxValue, TypeParam(1), Result)); 515 EXPECT_EQ(Result, std::numeric_limits<TypeParam>::min()); 516 } 517 518 TYPED_TEST(OverflowTest, AddOverflowToZero) { 519 TypeParam Result; 520 auto MinValue = std::numeric_limits<TypeParam>::min(); 521 EXPECT_TRUE(AddOverflow<TypeParam>(MinValue, MinValue, Result)); 522 EXPECT_EQ(Result, TypeParam(0)); 523 } 524 525 TYPED_TEST(OverflowTest, AddOverflowToMax) { 526 TypeParam Result; 527 auto MinValue = std::numeric_limits<TypeParam>::min(); 528 EXPECT_TRUE(AddOverflow<TypeParam>(MinValue, TypeParam(-1), Result)); 529 EXPECT_EQ(Result, std::numeric_limits<TypeParam>::max()); 530 } 531 532 TYPED_TEST(OverflowTest, SubNoOverflow) { 533 TypeParam Result; 534 EXPECT_FALSE(SubOverflow<TypeParam>(1, 2, Result)); 535 EXPECT_EQ(Result, TypeParam(-1)); 536 } 537 538 TYPED_TEST(OverflowTest, SubOverflowToMax) { 539 TypeParam Result; 540 auto MinValue = std::numeric_limits<TypeParam>::min(); 541 EXPECT_TRUE(SubOverflow<TypeParam>(0, MinValue, Result)); 542 EXPECT_EQ(Result, MinValue); 543 } 544 545 TYPED_TEST(OverflowTest, SubOverflowToMin) { 546 TypeParam Result; 547 auto MinValue = std::numeric_limits<TypeParam>::min(); 548 EXPECT_TRUE(SubOverflow<TypeParam>(0, MinValue, Result)); 549 EXPECT_EQ(Result, MinValue); 550 } 551 552 TYPED_TEST(OverflowTest, SubOverflowToNegative) { 553 TypeParam Result; 554 auto MaxValue = std::numeric_limits<TypeParam>::max(); 555 auto MinValue = std::numeric_limits<TypeParam>::min(); 556 EXPECT_TRUE(SubOverflow<TypeParam>(MaxValue, MinValue, Result)); 557 EXPECT_EQ(Result, TypeParam(-1)); 558 } 559 560 TYPED_TEST(OverflowTest, SubOverflowToPositive) { 561 TypeParam Result; 562 auto MaxValue = std::numeric_limits<TypeParam>::max(); 563 auto MinValue = std::numeric_limits<TypeParam>::min(); 564 EXPECT_TRUE(SubOverflow<TypeParam>(MinValue, MaxValue, Result)); 565 EXPECT_EQ(Result, TypeParam(1)); 566 } 567 568 TYPED_TEST(OverflowTest, MulNoOverflow) { 569 TypeParam Result; 570 EXPECT_FALSE(MulOverflow<TypeParam>(1, 2, Result)); 571 EXPECT_EQ(Result, 2); 572 EXPECT_FALSE(MulOverflow<TypeParam>(-1, 3, Result)); 573 EXPECT_EQ(Result, -3); 574 EXPECT_FALSE(MulOverflow<TypeParam>(4, -2, Result)); 575 EXPECT_EQ(Result, -8); 576 EXPECT_FALSE(MulOverflow<TypeParam>(-6, -5, Result)); 577 EXPECT_EQ(Result, 30); 578 } 579 580 TYPED_TEST(OverflowTest, MulNoOverflowToMax) { 581 TypeParam Result; 582 auto MaxValue = std::numeric_limits<TypeParam>::max(); 583 auto MinValue = std::numeric_limits<TypeParam>::min(); 584 EXPECT_FALSE(MulOverflow<TypeParam>(MinValue + 1, -1, Result)); 585 EXPECT_EQ(Result, MaxValue); 586 } 587 588 TYPED_TEST(OverflowTest, MulOverflowToMin) { 589 TypeParam Result; 590 auto MinValue = std::numeric_limits<TypeParam>::min(); 591 EXPECT_TRUE(MulOverflow<TypeParam>(MinValue, -1, Result)); 592 EXPECT_EQ(Result, MinValue); 593 } 594 595 TYPED_TEST(OverflowTest, MulOverflowMax) { 596 TypeParam Result; 597 auto MinValue = std::numeric_limits<TypeParam>::min(); 598 auto MaxValue = std::numeric_limits<TypeParam>::max(); 599 EXPECT_TRUE(MulOverflow<TypeParam>(MinValue, MinValue, Result)); 600 EXPECT_EQ(Result, 0); 601 EXPECT_TRUE(MulOverflow<TypeParam>(MaxValue, MaxValue, Result)); 602 EXPECT_EQ(Result, 1); 603 } 604 605 TYPED_TEST(OverflowTest, MulResultZero) { 606 TypeParam Result; 607 EXPECT_FALSE(MulOverflow<TypeParam>(4, 0, Result)); 608 EXPECT_EQ(Result, TypeParam(0)); 609 EXPECT_FALSE(MulOverflow<TypeParam>(-5, 0, Result)); 610 EXPECT_EQ(Result, TypeParam(0)); 611 EXPECT_FALSE(MulOverflow<TypeParam>(0, 5, Result)); 612 EXPECT_EQ(Result, TypeParam(0)); 613 EXPECT_FALSE(MulOverflow<TypeParam>(0, -5, Result)); 614 EXPECT_EQ(Result, TypeParam(0)); 615 } 616 617 } // namespace 618