1 // Copyright 2017 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "absl/numeric/int128.h"
16
17 #include <algorithm>
18 #include <limits>
19 #include <random>
20 #include <type_traits>
21 #include <utility>
22 #include <vector>
23
24 #include "gtest/gtest.h"
25 #include "absl/base/internal/cycleclock.h"
26 #include "absl/hash/hash_testing.h"
27 #include "absl/meta/type_traits.h"
28
29 #if defined(_MSC_VER) && _MSC_VER == 1900
30 // Disable "unary minus operator applied to unsigned type" warnings in Microsoft
31 // Visual C++ 14 (2015).
32 #pragma warning(disable:4146)
33 #endif
34
35 namespace {
36
37 template <typename T>
38 class Uint128IntegerTraitsTest : public ::testing::Test {};
39 typedef ::testing::Types<bool, char, signed char, unsigned char, char16_t,
40 char32_t, wchar_t,
41 short, // NOLINT(runtime/int)
42 unsigned short, // NOLINT(runtime/int)
43 int, unsigned int,
44 long, // NOLINT(runtime/int)
45 unsigned long, // NOLINT(runtime/int)
46 long long, // NOLINT(runtime/int)
47 unsigned long long> // NOLINT(runtime/int)
48 IntegerTypes;
49
50 template <typename T>
51 class Uint128FloatTraitsTest : public ::testing::Test {};
52 typedef ::testing::Types<float, double, long double> FloatingPointTypes;
53
54 TYPED_TEST_SUITE(Uint128IntegerTraitsTest, IntegerTypes);
55
TYPED_TEST(Uint128IntegerTraitsTest,ConstructAssignTest)56 TYPED_TEST(Uint128IntegerTraitsTest, ConstructAssignTest) {
57 static_assert(std::is_constructible<absl::uint128, TypeParam>::value,
58 "absl::uint128 must be constructible from TypeParam");
59 static_assert(std::is_assignable<absl::uint128&, TypeParam>::value,
60 "absl::uint128 must be assignable from TypeParam");
61 static_assert(!std::is_assignable<TypeParam&, absl::uint128>::value,
62 "TypeParam must not be assignable from absl::uint128");
63 }
64
65 TYPED_TEST_SUITE(Uint128FloatTraitsTest, FloatingPointTypes);
66
TYPED_TEST(Uint128FloatTraitsTest,ConstructAssignTest)67 TYPED_TEST(Uint128FloatTraitsTest, ConstructAssignTest) {
68 static_assert(std::is_constructible<absl::uint128, TypeParam>::value,
69 "absl::uint128 must be constructible from TypeParam");
70 static_assert(!std::is_assignable<absl::uint128&, TypeParam>::value,
71 "absl::uint128 must not be assignable from TypeParam");
72 static_assert(!std::is_assignable<TypeParam&, absl::uint128>::value,
73 "TypeParam must not be assignable from absl::uint128");
74 }
75
76 #ifdef ABSL_HAVE_INTRINSIC_INT128
77 // These type traits done separately as TYPED_TEST requires typeinfo, and not
78 // all platforms have this for __int128 even though they define the type.
TEST(Uint128,IntrinsicTypeTraitsTest)79 TEST(Uint128, IntrinsicTypeTraitsTest) {
80 static_assert(std::is_constructible<absl::uint128, __int128>::value,
81 "absl::uint128 must be constructible from __int128");
82 static_assert(std::is_assignable<absl::uint128&, __int128>::value,
83 "absl::uint128 must be assignable from __int128");
84 static_assert(!std::is_assignable<__int128&, absl::uint128>::value,
85 "__int128 must not be assignable from absl::uint128");
86
87 static_assert(std::is_constructible<absl::uint128, unsigned __int128>::value,
88 "absl::uint128 must be constructible from unsigned __int128");
89 static_assert(std::is_assignable<absl::uint128&, unsigned __int128>::value,
90 "absl::uint128 must be assignable from unsigned __int128");
91 static_assert(!std::is_assignable<unsigned __int128&, absl::uint128>::value,
92 "unsigned __int128 must not be assignable from absl::uint128");
93 }
94 #endif // ABSL_HAVE_INTRINSIC_INT128
95
TEST(Uint128,TrivialTraitsTest)96 TEST(Uint128, TrivialTraitsTest) {
97 static_assert(absl::is_trivially_default_constructible<absl::uint128>::value,
98 "");
99 static_assert(absl::is_trivially_copy_constructible<absl::uint128>::value,
100 "");
101 static_assert(absl::is_trivially_copy_assignable<absl::uint128>::value, "");
102 static_assert(std::is_trivially_destructible<absl::uint128>::value, "");
103 }
104
TEST(Uint128,AllTests)105 TEST(Uint128, AllTests) {
106 absl::uint128 zero = 0;
107 absl::uint128 one = 1;
108 absl::uint128 one_2arg = absl::MakeUint128(0, 1);
109 absl::uint128 two = 2;
110 absl::uint128 three = 3;
111 absl::uint128 big = absl::MakeUint128(2000, 2);
112 absl::uint128 big_minus_one = absl::MakeUint128(2000, 1);
113 absl::uint128 bigger = absl::MakeUint128(2001, 1);
114 absl::uint128 biggest = absl::Uint128Max();
115 absl::uint128 high_low = absl::MakeUint128(1, 0);
116 absl::uint128 low_high =
117 absl::MakeUint128(0, std::numeric_limits<uint64_t>::max());
118 EXPECT_LT(one, two);
119 EXPECT_GT(two, one);
120 EXPECT_LT(one, big);
121 EXPECT_LT(one, big);
122 EXPECT_EQ(one, one_2arg);
123 EXPECT_NE(one, two);
124 EXPECT_GT(big, one);
125 EXPECT_GE(big, two);
126 EXPECT_GE(big, big_minus_one);
127 EXPECT_GT(big, big_minus_one);
128 EXPECT_LT(big_minus_one, big);
129 EXPECT_LE(big_minus_one, big);
130 EXPECT_NE(big_minus_one, big);
131 EXPECT_LT(big, biggest);
132 EXPECT_LE(big, biggest);
133 EXPECT_GT(biggest, big);
134 EXPECT_GE(biggest, big);
135 EXPECT_EQ(big, ~~big);
136 EXPECT_EQ(one, one | one);
137 EXPECT_EQ(big, big | big);
138 EXPECT_EQ(one, one | zero);
139 EXPECT_EQ(one, one & one);
140 EXPECT_EQ(big, big & big);
141 EXPECT_EQ(zero, one & zero);
142 EXPECT_EQ(zero, big & ~big);
143 EXPECT_EQ(zero, one ^ one);
144 EXPECT_EQ(zero, big ^ big);
145 EXPECT_EQ(one, one ^ zero);
146
147 // Shift operators.
148 EXPECT_EQ(big, big << 0);
149 EXPECT_EQ(big, big >> 0);
150 EXPECT_GT(big << 1, big);
151 EXPECT_LT(big >> 1, big);
152 EXPECT_EQ(big, (big << 10) >> 10);
153 EXPECT_EQ(big, (big >> 1) << 1);
154 EXPECT_EQ(one, (one << 80) >> 80);
155 EXPECT_EQ(zero, (one >> 80) << 80);
156
157 // Shift assignments.
158 absl::uint128 big_copy = big;
159 EXPECT_EQ(big << 0, big_copy <<= 0);
160 big_copy = big;
161 EXPECT_EQ(big >> 0, big_copy >>= 0);
162 big_copy = big;
163 EXPECT_EQ(big << 1, big_copy <<= 1);
164 big_copy = big;
165 EXPECT_EQ(big >> 1, big_copy >>= 1);
166 big_copy = big;
167 EXPECT_EQ(big << 10, big_copy <<= 10);
168 big_copy = big;
169 EXPECT_EQ(big >> 10, big_copy >>= 10);
170 big_copy = big;
171 EXPECT_EQ(big << 64, big_copy <<= 64);
172 big_copy = big;
173 EXPECT_EQ(big >> 64, big_copy >>= 64);
174 big_copy = big;
175 EXPECT_EQ(big << 73, big_copy <<= 73);
176 big_copy = big;
177 EXPECT_EQ(big >> 73, big_copy >>= 73);
178
179 EXPECT_EQ(absl::Uint128High64(biggest), std::numeric_limits<uint64_t>::max());
180 EXPECT_EQ(absl::Uint128Low64(biggest), std::numeric_limits<uint64_t>::max());
181 EXPECT_EQ(zero + one, one);
182 EXPECT_EQ(one + one, two);
183 EXPECT_EQ(big_minus_one + one, big);
184 EXPECT_EQ(one - one, zero);
185 EXPECT_EQ(one - zero, one);
186 EXPECT_EQ(zero - one, biggest);
187 EXPECT_EQ(big - big, zero);
188 EXPECT_EQ(big - one, big_minus_one);
189 EXPECT_EQ(big + std::numeric_limits<uint64_t>::max(), bigger);
190 EXPECT_EQ(biggest + 1, zero);
191 EXPECT_EQ(zero - 1, biggest);
192 EXPECT_EQ(high_low - one, low_high);
193 EXPECT_EQ(low_high + one, high_low);
194 EXPECT_EQ(absl::Uint128High64((absl::uint128(1) << 64) - 1), 0);
195 EXPECT_EQ(absl::Uint128Low64((absl::uint128(1) << 64) - 1),
196 std::numeric_limits<uint64_t>::max());
197 EXPECT_TRUE(!!one);
198 EXPECT_TRUE(!!high_low);
199 EXPECT_FALSE(!!zero);
200 EXPECT_FALSE(!one);
201 EXPECT_FALSE(!high_low);
202 EXPECT_TRUE(!zero);
203 EXPECT_TRUE(zero == 0); // NOLINT(readability/check)
204 EXPECT_FALSE(zero != 0); // NOLINT(readability/check)
205 EXPECT_FALSE(one == 0); // NOLINT(readability/check)
206 EXPECT_TRUE(one != 0); // NOLINT(readability/check)
207 EXPECT_FALSE(high_low == 0); // NOLINT(readability/check)
208 EXPECT_TRUE(high_low != 0); // NOLINT(readability/check)
209
210 absl::uint128 test = zero;
211 EXPECT_EQ(++test, one);
212 EXPECT_EQ(test, one);
213 EXPECT_EQ(test++, one);
214 EXPECT_EQ(test, two);
215 EXPECT_EQ(test -= 2, zero);
216 EXPECT_EQ(test, zero);
217 EXPECT_EQ(test += 2, two);
218 EXPECT_EQ(test, two);
219 EXPECT_EQ(--test, one);
220 EXPECT_EQ(test, one);
221 EXPECT_EQ(test--, one);
222 EXPECT_EQ(test, zero);
223 EXPECT_EQ(test |= three, three);
224 EXPECT_EQ(test &= one, one);
225 EXPECT_EQ(test ^= three, two);
226 EXPECT_EQ(test >>= 1, one);
227 EXPECT_EQ(test <<= 1, two);
228
229 EXPECT_EQ(big, +big);
230 EXPECT_EQ(two, +two);
231 EXPECT_EQ(absl::Uint128Max(), +absl::Uint128Max());
232 EXPECT_EQ(zero, +zero);
233
234 EXPECT_EQ(big, -(-big));
235 EXPECT_EQ(two, -((-one) - 1));
236 EXPECT_EQ(absl::Uint128Max(), -one);
237 EXPECT_EQ(zero, -zero);
238
239 EXPECT_EQ(absl::Uint128Max(), absl::kuint128max);
240 }
241
TEST(Int128,RightShiftOfNegativeNumbers)242 TEST(Int128, RightShiftOfNegativeNumbers) {
243 absl::int128 minus_six = -6;
244 absl::int128 minus_three = -3;
245 absl::int128 minus_two = -2;
246 absl::int128 minus_one = -1;
247 if ((-6 >> 1) == -3) {
248 // Right shift is arithmetic (sign propagates)
249 EXPECT_EQ(minus_six >> 1, minus_three);
250 EXPECT_EQ(minus_six >> 2, minus_two);
251 EXPECT_EQ(minus_six >> 65, minus_one);
252 } else {
253 // Right shift is logical (zeros shifted in at MSB)
254 EXPECT_EQ(minus_six >> 1, absl::int128(absl::uint128(minus_six) >> 1));
255 EXPECT_EQ(minus_six >> 2, absl::int128(absl::uint128(minus_six) >> 2));
256 EXPECT_EQ(minus_six >> 65, absl::int128(absl::uint128(minus_six) >> 65));
257 }
258 }
259
TEST(Uint128,ConversionTests)260 TEST(Uint128, ConversionTests) {
261 EXPECT_TRUE(absl::MakeUint128(1, 0));
262
263 #ifdef ABSL_HAVE_INTRINSIC_INT128
264 unsigned __int128 intrinsic =
265 (static_cast<unsigned __int128>(0x3a5b76c209de76f6) << 64) +
266 0x1f25e1d63a2b46c5;
267 absl::uint128 custom =
268 absl::MakeUint128(0x3a5b76c209de76f6, 0x1f25e1d63a2b46c5);
269
270 EXPECT_EQ(custom, absl::uint128(intrinsic));
271 EXPECT_EQ(custom, absl::uint128(static_cast<__int128>(intrinsic)));
272 EXPECT_EQ(intrinsic, static_cast<unsigned __int128>(custom));
273 EXPECT_EQ(intrinsic, static_cast<__int128>(custom));
274 #endif // ABSL_HAVE_INTRINSIC_INT128
275
276 // verify that an integer greater than 2**64 that can be stored precisely
277 // inside a double is converted to a absl::uint128 without loss of
278 // information.
279 double precise_double = 0x530e * std::pow(2.0, 64.0) + 0xda74000000000000;
280 absl::uint128 from_precise_double(precise_double);
281 absl::uint128 from_precise_ints =
282 absl::MakeUint128(0x530e, 0xda74000000000000);
283 EXPECT_EQ(from_precise_double, from_precise_ints);
284 EXPECT_DOUBLE_EQ(static_cast<double>(from_precise_ints), precise_double);
285
286 double approx_double = 0xffffeeeeddddcccc * std::pow(2.0, 64.0) +
287 0xbbbbaaaa99998888;
288 absl::uint128 from_approx_double(approx_double);
289 EXPECT_DOUBLE_EQ(static_cast<double>(from_approx_double), approx_double);
290
291 double round_to_zero = 0.7;
292 double round_to_five = 5.8;
293 double round_to_nine = 9.3;
294 EXPECT_EQ(static_cast<absl::uint128>(round_to_zero), 0);
295 EXPECT_EQ(static_cast<absl::uint128>(round_to_five), 5);
296 EXPECT_EQ(static_cast<absl::uint128>(round_to_nine), 9);
297
298 absl::uint128 highest_precision_in_long_double =
299 ~absl::uint128{} >> (128 - std::numeric_limits<long double>::digits);
300 EXPECT_EQ(highest_precision_in_long_double,
301 static_cast<absl::uint128>(
302 static_cast<long double>(highest_precision_in_long_double)));
303 // Apply a mask just to make sure all the bits are the right place.
304 const absl::uint128 arbitrary_mask =
305 absl::MakeUint128(0xa29f622677ded751, 0xf8ca66add076f468);
306 EXPECT_EQ(highest_precision_in_long_double & arbitrary_mask,
307 static_cast<absl::uint128>(static_cast<long double>(
308 highest_precision_in_long_double & arbitrary_mask)));
309
310 EXPECT_EQ(static_cast<absl::uint128>(-0.1L), 0);
311 }
312
TEST(Uint128,OperatorAssignReturnRef)313 TEST(Uint128, OperatorAssignReturnRef) {
314 absl::uint128 v(1);
315 (v += 4) -= 3;
316 EXPECT_EQ(2, v);
317 }
318
TEST(Uint128,Multiply)319 TEST(Uint128, Multiply) {
320 absl::uint128 a, b, c;
321
322 // Zero test.
323 a = 0;
324 b = 0;
325 c = a * b;
326 EXPECT_EQ(0, c);
327
328 // Max carries.
329 a = absl::uint128(0) - 1;
330 b = absl::uint128(0) - 1;
331 c = a * b;
332 EXPECT_EQ(1, c);
333
334 // Self-operation with max carries.
335 c = absl::uint128(0) - 1;
336 c *= c;
337 EXPECT_EQ(1, c);
338
339 // 1-bit x 1-bit.
340 for (int i = 0; i < 64; ++i) {
341 for (int j = 0; j < 64; ++j) {
342 a = absl::uint128(1) << i;
343 b = absl::uint128(1) << j;
344 c = a * b;
345 EXPECT_EQ(absl::uint128(1) << (i + j), c);
346 }
347 }
348
349 // Verified with dc.
350 a = absl::MakeUint128(0xffffeeeeddddcccc, 0xbbbbaaaa99998888);
351 b = absl::MakeUint128(0x7777666655554444, 0x3333222211110000);
352 c = a * b;
353 EXPECT_EQ(absl::MakeUint128(0x530EDA741C71D4C3, 0xBF25975319080000), c);
354 EXPECT_EQ(0, c - b * a);
355 EXPECT_EQ(a*a - b*b, (a+b) * (a-b));
356
357 // Verified with dc.
358 a = absl::MakeUint128(0x0123456789abcdef, 0xfedcba9876543210);
359 b = absl::MakeUint128(0x02468ace13579bdf, 0xfdb97531eca86420);
360 c = a * b;
361 EXPECT_EQ(absl::MakeUint128(0x97a87f4f261ba3f2, 0x342d0bbf48948200), c);
362 EXPECT_EQ(0, c - b * a);
363 EXPECT_EQ(a*a - b*b, (a+b) * (a-b));
364 }
365
TEST(Uint128,AliasTests)366 TEST(Uint128, AliasTests) {
367 absl::uint128 x1 = absl::MakeUint128(1, 2);
368 absl::uint128 x2 = absl::MakeUint128(2, 4);
369 x1 += x1;
370 EXPECT_EQ(x2, x1);
371
372 absl::uint128 x3 = absl::MakeUint128(1, static_cast<uint64_t>(1) << 63);
373 absl::uint128 x4 = absl::MakeUint128(3, 0);
374 x3 += x3;
375 EXPECT_EQ(x4, x3);
376 }
377
TEST(Uint128,DivideAndMod)378 TEST(Uint128, DivideAndMod) {
379 using std::swap;
380
381 // a := q * b + r
382 absl::uint128 a, b, q, r;
383
384 // Zero test.
385 a = 0;
386 b = 123;
387 q = a / b;
388 r = a % b;
389 EXPECT_EQ(0, q);
390 EXPECT_EQ(0, r);
391
392 a = absl::MakeUint128(0x530eda741c71d4c3, 0xbf25975319080000);
393 q = absl::MakeUint128(0x4de2cab081, 0x14c34ab4676e4bab);
394 b = absl::uint128(0x1110001);
395 r = absl::uint128(0x3eb455);
396 ASSERT_EQ(a, q * b + r); // Sanity-check.
397
398 absl::uint128 result_q, result_r;
399 result_q = a / b;
400 result_r = a % b;
401 EXPECT_EQ(q, result_q);
402 EXPECT_EQ(r, result_r);
403
404 // Try the other way around.
405 swap(q, b);
406 result_q = a / b;
407 result_r = a % b;
408 EXPECT_EQ(q, result_q);
409 EXPECT_EQ(r, result_r);
410 // Restore.
411 swap(b, q);
412
413 // Dividend < divisor; result should be q:0 r:<dividend>.
414 swap(a, b);
415 result_q = a / b;
416 result_r = a % b;
417 EXPECT_EQ(0, result_q);
418 EXPECT_EQ(a, result_r);
419 // Try the other way around.
420 swap(a, q);
421 result_q = a / b;
422 result_r = a % b;
423 EXPECT_EQ(0, result_q);
424 EXPECT_EQ(a, result_r);
425 // Restore.
426 swap(q, a);
427 swap(b, a);
428
429 // Try a large remainder.
430 b = a / 2 + 1;
431 absl::uint128 expected_r =
432 absl::MakeUint128(0x29876d3a0e38ea61, 0xdf92cba98c83ffff);
433 // Sanity checks.
434 ASSERT_EQ(a / 2 - 1, expected_r);
435 ASSERT_EQ(a, b + expected_r);
436 result_q = a / b;
437 result_r = a % b;
438 EXPECT_EQ(1, result_q);
439 EXPECT_EQ(expected_r, result_r);
440 }
441
TEST(Uint128,DivideAndModRandomInputs)442 TEST(Uint128, DivideAndModRandomInputs) {
443 const int kNumIters = 1 << 18;
444 std::minstd_rand random(testing::UnitTest::GetInstance()->random_seed());
445 std::uniform_int_distribution<uint64_t> uniform_uint64;
446 for (int i = 0; i < kNumIters; ++i) {
447 const absl::uint128 a =
448 absl::MakeUint128(uniform_uint64(random), uniform_uint64(random));
449 const absl::uint128 b =
450 absl::MakeUint128(uniform_uint64(random), uniform_uint64(random));
451 if (b == 0) {
452 continue; // Avoid a div-by-zero.
453 }
454 const absl::uint128 q = a / b;
455 const absl::uint128 r = a % b;
456 ASSERT_EQ(a, b * q + r);
457 }
458 }
459
TEST(Uint128,ConstexprTest)460 TEST(Uint128, ConstexprTest) {
461 constexpr absl::uint128 zero = absl::uint128();
462 constexpr absl::uint128 one = 1;
463 constexpr absl::uint128 minus_two = -2;
464 EXPECT_EQ(zero, absl::uint128(0));
465 EXPECT_EQ(one, absl::uint128(1));
466 EXPECT_EQ(minus_two, absl::MakeUint128(-1, -2));
467 }
468
TEST(Uint128,NumericLimitsTest)469 TEST(Uint128, NumericLimitsTest) {
470 static_assert(std::numeric_limits<absl::uint128>::is_specialized, "");
471 static_assert(!std::numeric_limits<absl::uint128>::is_signed, "");
472 static_assert(std::numeric_limits<absl::uint128>::is_integer, "");
473 EXPECT_EQ(static_cast<int>(128 * std::log10(2)),
474 std::numeric_limits<absl::uint128>::digits10);
475 EXPECT_EQ(0, std::numeric_limits<absl::uint128>::min());
476 EXPECT_EQ(0, std::numeric_limits<absl::uint128>::lowest());
477 EXPECT_EQ(absl::Uint128Max(), std::numeric_limits<absl::uint128>::max());
478 }
479
TEST(Uint128,Hash)480 TEST(Uint128, Hash) {
481 EXPECT_TRUE(absl::VerifyTypeImplementsAbslHashCorrectly({
482 // Some simple values
483 absl::uint128{0},
484 absl::uint128{1},
485 ~absl::uint128{},
486 // 64 bit limits
487 absl::uint128{std::numeric_limits<int64_t>::max()},
488 absl::uint128{std::numeric_limits<uint64_t>::max()} + 0,
489 absl::uint128{std::numeric_limits<uint64_t>::max()} + 1,
490 absl::uint128{std::numeric_limits<uint64_t>::max()} + 2,
491 // Keeping high same
492 absl::uint128{1} << 62,
493 absl::uint128{1} << 63,
494 // Keeping low same
495 absl::uint128{1} << 64,
496 absl::uint128{1} << 65,
497 // 128 bit limits
498 std::numeric_limits<absl::uint128>::max(),
499 std::numeric_limits<absl::uint128>::max() - 1,
500 std::numeric_limits<absl::uint128>::min() + 1,
501 std::numeric_limits<absl::uint128>::min(),
502 }));
503 }
504
505
TEST(Int128Uint128,ConversionTest)506 TEST(Int128Uint128, ConversionTest) {
507 absl::int128 nonnegative_signed_values[] = {
508 0,
509 1,
510 0xffeeddccbbaa9988,
511 absl::MakeInt128(0x7766554433221100, 0),
512 absl::MakeInt128(0x1234567890abcdef, 0xfedcba0987654321),
513 absl::Int128Max()};
514 for (absl::int128 value : nonnegative_signed_values) {
515 EXPECT_EQ(value, absl::int128(absl::uint128(value)));
516
517 absl::uint128 assigned_value;
518 assigned_value = value;
519 EXPECT_EQ(value, absl::int128(assigned_value));
520 }
521
522 absl::int128 negative_values[] = {
523 -1, -0x1234567890abcdef,
524 absl::MakeInt128(-0x5544332211ffeedd, 0),
525 -absl::MakeInt128(0x76543210fedcba98, 0xabcdef0123456789)};
526 for (absl::int128 value : negative_values) {
527 EXPECT_EQ(absl::uint128(-value), -absl::uint128(value));
528
529 absl::uint128 assigned_value;
530 assigned_value = value;
531 EXPECT_EQ(absl::uint128(-value), -assigned_value);
532 }
533 }
534
535 template <typename T>
536 class Int128IntegerTraitsTest : public ::testing::Test {};
537
538 TYPED_TEST_SUITE(Int128IntegerTraitsTest, IntegerTypes);
539
TYPED_TEST(Int128IntegerTraitsTest,ConstructAssignTest)540 TYPED_TEST(Int128IntegerTraitsTest, ConstructAssignTest) {
541 static_assert(std::is_constructible<absl::int128, TypeParam>::value,
542 "absl::int128 must be constructible from TypeParam");
543 static_assert(std::is_assignable<absl::int128&, TypeParam>::value,
544 "absl::int128 must be assignable from TypeParam");
545 static_assert(!std::is_assignable<TypeParam&, absl::int128>::value,
546 "TypeParam must not be assignable from absl::int128");
547 }
548
549 template <typename T>
550 class Int128FloatTraitsTest : public ::testing::Test {};
551
552 TYPED_TEST_SUITE(Int128FloatTraitsTest, FloatingPointTypes);
553
TYPED_TEST(Int128FloatTraitsTest,ConstructAssignTest)554 TYPED_TEST(Int128FloatTraitsTest, ConstructAssignTest) {
555 static_assert(std::is_constructible<absl::int128, TypeParam>::value,
556 "absl::int128 must be constructible from TypeParam");
557 static_assert(!std::is_assignable<absl::int128&, TypeParam>::value,
558 "absl::int128 must not be assignable from TypeParam");
559 static_assert(!std::is_assignable<TypeParam&, absl::int128>::value,
560 "TypeParam must not be assignable from absl::int128");
561 }
562
563 #ifdef ABSL_HAVE_INTRINSIC_INT128
564 // These type traits done separately as TYPED_TEST requires typeinfo, and not
565 // all platforms have this for __int128 even though they define the type.
TEST(Int128,IntrinsicTypeTraitsTest)566 TEST(Int128, IntrinsicTypeTraitsTest) {
567 static_assert(std::is_constructible<absl::int128, __int128>::value,
568 "absl::int128 must be constructible from __int128");
569 static_assert(std::is_assignable<absl::int128&, __int128>::value,
570 "absl::int128 must be assignable from __int128");
571 static_assert(!std::is_assignable<__int128&, absl::int128>::value,
572 "__int128 must not be assignable from absl::int128");
573
574 static_assert(std::is_constructible<absl::int128, unsigned __int128>::value,
575 "absl::int128 must be constructible from unsigned __int128");
576 static_assert(!std::is_assignable<absl::int128&, unsigned __int128>::value,
577 "absl::int128 must be assignable from unsigned __int128");
578 static_assert(!std::is_assignable<unsigned __int128&, absl::int128>::value,
579 "unsigned __int128 must not be assignable from absl::int128");
580 }
581 #endif // ABSL_HAVE_INTRINSIC_INT128
582
TEST(Int128,TrivialTraitsTest)583 TEST(Int128, TrivialTraitsTest) {
584 static_assert(absl::is_trivially_default_constructible<absl::int128>::value,
585 "");
586 static_assert(absl::is_trivially_copy_constructible<absl::int128>::value, "");
587 static_assert(absl::is_trivially_copy_assignable<absl::int128>::value, "");
588 static_assert(std::is_trivially_destructible<absl::int128>::value, "");
589 }
590
TEST(Int128,BoolConversionTest)591 TEST(Int128, BoolConversionTest) {
592 EXPECT_FALSE(absl::int128(0));
593 for (int i = 0; i < 64; ++i) {
594 EXPECT_TRUE(absl::MakeInt128(0, uint64_t{1} << i));
595 }
596 for (int i = 0; i < 63; ++i) {
597 EXPECT_TRUE(absl::MakeInt128(int64_t{1} << i, 0));
598 }
599 EXPECT_TRUE(absl::Int128Min());
600
601 EXPECT_EQ(absl::int128(1), absl::int128(true));
602 EXPECT_EQ(absl::int128(0), absl::int128(false));
603 }
604
605 template <typename T>
606 class Int128IntegerConversionTest : public ::testing::Test {};
607
608 TYPED_TEST_SUITE(Int128IntegerConversionTest, IntegerTypes);
609
TYPED_TEST(Int128IntegerConversionTest,RoundTripTest)610 TYPED_TEST(Int128IntegerConversionTest, RoundTripTest) {
611 EXPECT_EQ(TypeParam{0}, static_cast<TypeParam>(absl::int128(0)));
612 EXPECT_EQ(std::numeric_limits<TypeParam>::min(),
613 static_cast<TypeParam>(
614 absl::int128(std::numeric_limits<TypeParam>::min())));
615 EXPECT_EQ(std::numeric_limits<TypeParam>::max(),
616 static_cast<TypeParam>(
617 absl::int128(std::numeric_limits<TypeParam>::max())));
618 }
619
620 template <typename T>
621 class Int128FloatConversionTest : public ::testing::Test {};
622
623 TYPED_TEST_SUITE(Int128FloatConversionTest, FloatingPointTypes);
624
TYPED_TEST(Int128FloatConversionTest,ConstructAndCastTest)625 TYPED_TEST(Int128FloatConversionTest, ConstructAndCastTest) {
626 // Conversions where the floating point values should be exactly the same.
627 // 0x9f5b is a randomly chosen small value.
628 for (int i = 0; i < 110; ++i) { // 110 = 126 - #bits in 0x9f5b
629 SCOPED_TRACE(::testing::Message() << "i = " << i);
630
631 TypeParam float_value = std::ldexp(static_cast<TypeParam>(0x9f5b), i);
632 absl::int128 int_value = absl::int128(0x9f5b) << i;
633
634 EXPECT_EQ(float_value, static_cast<TypeParam>(int_value));
635 EXPECT_EQ(-float_value, static_cast<TypeParam>(-int_value));
636 EXPECT_EQ(int_value, absl::int128(float_value));
637 EXPECT_EQ(-int_value, absl::int128(-float_value));
638 }
639
640 // Round trip conversions with a small sample of randomly generated uint64_t
641 // values (less than int64_t max so that value * 2^64 fits into int128).
642 uint64_t values[] = {0x6d4492c24fb86199, 0x26ead65e4cb359b5,
643 0x2c43407433ba3fd1, 0x3b574ec668df6b55,
644 0x1c750e55a29f4f0f};
645 for (uint64_t value : values) {
646 for (int i = 0; i <= 64; ++i) {
647 SCOPED_TRACE(::testing::Message()
648 << "value = " << value << "; i = " << i);
649
650 TypeParam fvalue = std::ldexp(static_cast<TypeParam>(value), i);
651 EXPECT_DOUBLE_EQ(fvalue, static_cast<TypeParam>(absl::int128(fvalue)));
652 EXPECT_DOUBLE_EQ(-fvalue, static_cast<TypeParam>(-absl::int128(fvalue)));
653 EXPECT_DOUBLE_EQ(-fvalue, static_cast<TypeParam>(absl::int128(-fvalue)));
654 EXPECT_DOUBLE_EQ(fvalue, static_cast<TypeParam>(-absl::int128(-fvalue)));
655 }
656 }
657
658 // Round trip conversions with a small sample of random large positive values.
659 absl::int128 large_values[] = {
660 absl::MakeInt128(0x5b0640d96c7b3d9f, 0xb7a7189e51d18622),
661 absl::MakeInt128(0x34bed042c6f65270, 0x73b236570669a089),
662 absl::MakeInt128(0x43deba9e6da12724, 0xf7f0f83da686797d),
663 absl::MakeInt128(0x71e8d383be4e5589, 0x75c3f96fb00752b6)};
664 for (absl::int128 value : large_values) {
665 // Make value have as many significant bits as can be represented by
666 // the mantissa, also making sure the highest and lowest bit in the range
667 // are set.
668 value >>= (127 - std::numeric_limits<TypeParam>::digits);
669 value |= absl::int128(1) << (std::numeric_limits<TypeParam>::digits - 1);
670 value |= 1;
671 for (int i = 0; i < 127 - std::numeric_limits<TypeParam>::digits; ++i) {
672 absl::int128 int_value = value << i;
673 EXPECT_EQ(int_value,
674 static_cast<absl::int128>(static_cast<TypeParam>(int_value)));
675 EXPECT_EQ(-int_value,
676 static_cast<absl::int128>(static_cast<TypeParam>(-int_value)));
677 }
678 }
679
680 // Small sample of checks that rounding is toward zero
681 EXPECT_EQ(0, absl::int128(TypeParam(0.1)));
682 EXPECT_EQ(17, absl::int128(TypeParam(17.8)));
683 EXPECT_EQ(0, absl::int128(TypeParam(-0.8)));
684 EXPECT_EQ(-53, absl::int128(TypeParam(-53.1)));
685 EXPECT_EQ(0, absl::int128(TypeParam(0.5)));
686 EXPECT_EQ(0, absl::int128(TypeParam(-0.5)));
687 TypeParam just_lt_one = std::nexttoward(TypeParam(1), TypeParam(0));
688 EXPECT_EQ(0, absl::int128(just_lt_one));
689 TypeParam just_gt_minus_one = std::nexttoward(TypeParam(-1), TypeParam(0));
690 EXPECT_EQ(0, absl::int128(just_gt_minus_one));
691
692 // Check limits
693 EXPECT_DOUBLE_EQ(std::ldexp(static_cast<TypeParam>(1), 127),
694 static_cast<TypeParam>(absl::Int128Max()));
695 EXPECT_DOUBLE_EQ(-std::ldexp(static_cast<TypeParam>(1), 127),
696 static_cast<TypeParam>(absl::Int128Min()));
697 }
698
TEST(Int128,FactoryTest)699 TEST(Int128, FactoryTest) {
700 EXPECT_EQ(absl::int128(-1), absl::MakeInt128(-1, -1));
701 EXPECT_EQ(absl::int128(-31), absl::MakeInt128(-1, -31));
702 EXPECT_EQ(absl::int128(std::numeric_limits<int64_t>::min()),
703 absl::MakeInt128(-1, std::numeric_limits<int64_t>::min()));
704 EXPECT_EQ(absl::int128(0), absl::MakeInt128(0, 0));
705 EXPECT_EQ(absl::int128(1), absl::MakeInt128(0, 1));
706 EXPECT_EQ(absl::int128(std::numeric_limits<int64_t>::max()),
707 absl::MakeInt128(0, std::numeric_limits<int64_t>::max()));
708 }
709
TEST(Int128,HighLowTest)710 TEST(Int128, HighLowTest) {
711 struct HighLowPair {
712 int64_t high;
713 uint64_t low;
714 };
715 HighLowPair values[]{{0, 0}, {0, 1}, {1, 0}, {123, 456}, {-654, 321}};
716 for (const HighLowPair& pair : values) {
717 absl::int128 value = absl::MakeInt128(pair.high, pair.low);
718 EXPECT_EQ(pair.low, absl::Int128Low64(value));
719 EXPECT_EQ(pair.high, absl::Int128High64(value));
720 }
721 }
722
TEST(Int128,LimitsTest)723 TEST(Int128, LimitsTest) {
724 EXPECT_EQ(absl::MakeInt128(0x7fffffffffffffff, 0xffffffffffffffff),
725 absl::Int128Max());
726 EXPECT_EQ(absl::Int128Max(), ~absl::Int128Min());
727 }
728
729 #if defined(ABSL_HAVE_INTRINSIC_INT128)
TEST(Int128,IntrinsicConversionTest)730 TEST(Int128, IntrinsicConversionTest) {
731 __int128 intrinsic =
732 (static_cast<__int128>(0x3a5b76c209de76f6) << 64) + 0x1f25e1d63a2b46c5;
733 absl::int128 custom =
734 absl::MakeInt128(0x3a5b76c209de76f6, 0x1f25e1d63a2b46c5);
735
736 EXPECT_EQ(custom, absl::int128(intrinsic));
737 EXPECT_EQ(intrinsic, static_cast<__int128>(custom));
738 }
739 #endif // ABSL_HAVE_INTRINSIC_INT128
740
TEST(Int128,ConstexprTest)741 TEST(Int128, ConstexprTest) {
742 constexpr absl::int128 zero = absl::int128();
743 constexpr absl::int128 one = 1;
744 constexpr absl::int128 minus_two = -2;
745 constexpr absl::int128 min = absl::Int128Min();
746 constexpr absl::int128 max = absl::Int128Max();
747 EXPECT_EQ(zero, absl::int128(0));
748 EXPECT_EQ(one, absl::int128(1));
749 EXPECT_EQ(minus_two, absl::MakeInt128(-1, -2));
750 EXPECT_GT(max, one);
751 EXPECT_LT(min, minus_two);
752 }
753
TEST(Int128,ComparisonTest)754 TEST(Int128, ComparisonTest) {
755 struct TestCase {
756 absl::int128 smaller;
757 absl::int128 larger;
758 };
759 TestCase cases[] = {
760 {absl::int128(0), absl::int128(123)},
761 {absl::MakeInt128(-12, 34), absl::MakeInt128(12, 34)},
762 {absl::MakeInt128(1, 1000), absl::MakeInt128(1000, 1)},
763 {absl::MakeInt128(-1000, 1000), absl::MakeInt128(-1, 1)},
764 };
765 for (const TestCase& pair : cases) {
766 SCOPED_TRACE(::testing::Message() << "pair.smaller = " << pair.smaller
767 << "; pair.larger = " << pair.larger);
768
769 EXPECT_TRUE(pair.smaller == pair.smaller); // NOLINT(readability/check)
770 EXPECT_TRUE(pair.larger == pair.larger); // NOLINT(readability/check)
771 EXPECT_FALSE(pair.smaller == pair.larger); // NOLINT(readability/check)
772
773 EXPECT_TRUE(pair.smaller != pair.larger); // NOLINT(readability/check)
774 EXPECT_FALSE(pair.smaller != pair.smaller); // NOLINT(readability/check)
775 EXPECT_FALSE(pair.larger != pair.larger); // NOLINT(readability/check)
776
777 EXPECT_TRUE(pair.smaller < pair.larger); // NOLINT(readability/check)
778 EXPECT_FALSE(pair.larger < pair.smaller); // NOLINT(readability/check)
779
780 EXPECT_TRUE(pair.larger > pair.smaller); // NOLINT(readability/check)
781 EXPECT_FALSE(pair.smaller > pair.larger); // NOLINT(readability/check)
782
783 EXPECT_TRUE(pair.smaller <= pair.larger); // NOLINT(readability/check)
784 EXPECT_FALSE(pair.larger <= pair.smaller); // NOLINT(readability/check)
785 EXPECT_TRUE(pair.smaller <= pair.smaller); // NOLINT(readability/check)
786 EXPECT_TRUE(pair.larger <= pair.larger); // NOLINT(readability/check)
787
788 EXPECT_TRUE(pair.larger >= pair.smaller); // NOLINT(readability/check)
789 EXPECT_FALSE(pair.smaller >= pair.larger); // NOLINT(readability/check)
790 EXPECT_TRUE(pair.smaller >= pair.smaller); // NOLINT(readability/check)
791 EXPECT_TRUE(pair.larger >= pair.larger); // NOLINT(readability/check)
792 }
793 }
794
TEST(Int128,UnaryPlusTest)795 TEST(Int128, UnaryPlusTest) {
796 int64_t values64[] = {0, 1, 12345, 0x4000000000000000,
797 std::numeric_limits<int64_t>::max()};
798 for (int64_t value : values64) {
799 SCOPED_TRACE(::testing::Message() << "value = " << value);
800
801 EXPECT_EQ(absl::int128(value), +absl::int128(value));
802 EXPECT_EQ(absl::int128(-value), +absl::int128(-value));
803 EXPECT_EQ(absl::MakeInt128(value, 0), +absl::MakeInt128(value, 0));
804 EXPECT_EQ(absl::MakeInt128(-value, 0), +absl::MakeInt128(-value, 0));
805 }
806 }
807
TEST(Int128,UnaryNegationTest)808 TEST(Int128, UnaryNegationTest) {
809 int64_t values64[] = {0, 1, 12345, 0x4000000000000000,
810 std::numeric_limits<int64_t>::max()};
811 for (int64_t value : values64) {
812 SCOPED_TRACE(::testing::Message() << "value = " << value);
813
814 EXPECT_EQ(absl::int128(-value), -absl::int128(value));
815 EXPECT_EQ(absl::int128(value), -absl::int128(-value));
816 EXPECT_EQ(absl::MakeInt128(-value, 0), -absl::MakeInt128(value, 0));
817 EXPECT_EQ(absl::MakeInt128(value, 0), -absl::MakeInt128(-value, 0));
818 }
819 }
820
TEST(Int128,LogicalNotTest)821 TEST(Int128, LogicalNotTest) {
822 EXPECT_TRUE(!absl::int128(0));
823 for (int i = 0; i < 64; ++i) {
824 EXPECT_FALSE(!absl::MakeInt128(0, uint64_t{1} << i));
825 }
826 for (int i = 0; i < 63; ++i) {
827 EXPECT_FALSE(!absl::MakeInt128(int64_t{1} << i, 0));
828 }
829 }
830
TEST(Int128,AdditionSubtractionTest)831 TEST(Int128, AdditionSubtractionTest) {
832 // 64 bit pairs that will not cause overflow / underflow. These test negative
833 // carry; positive carry must be checked separately.
834 std::pair<int64_t, int64_t> cases[]{
835 {0, 0}, // 0, 0
836 {0, 2945781290834}, // 0, +
837 {1908357619234, 0}, // +, 0
838 {0, -1204895918245}, // 0, -
839 {-2957928523560, 0}, // -, 0
840 {89023982312461, 98346012567134}, // +, +
841 {-63454234568239, -23456235230773}, // -, -
842 {98263457263502, -21428561935925}, // +, -
843 {-88235237438467, 15923659234573}, // -, +
844 };
845 for (const auto& pair : cases) {
846 SCOPED_TRACE(::testing::Message()
847 << "pair = {" << pair.first << ", " << pair.second << '}');
848
849 EXPECT_EQ(absl::int128(pair.first + pair.second),
850 absl::int128(pair.first) + absl::int128(pair.second));
851 EXPECT_EQ(absl::int128(pair.second + pair.first),
852 absl::int128(pair.second) += absl::int128(pair.first));
853
854 EXPECT_EQ(absl::int128(pair.first - pair.second),
855 absl::int128(pair.first) - absl::int128(pair.second));
856 EXPECT_EQ(absl::int128(pair.second - pair.first),
857 absl::int128(pair.second) -= absl::int128(pair.first));
858
859 EXPECT_EQ(
860 absl::MakeInt128(pair.second + pair.first, 0),
861 absl::MakeInt128(pair.second, 0) + absl::MakeInt128(pair.first, 0));
862 EXPECT_EQ(
863 absl::MakeInt128(pair.first + pair.second, 0),
864 absl::MakeInt128(pair.first, 0) += absl::MakeInt128(pair.second, 0));
865
866 EXPECT_EQ(
867 absl::MakeInt128(pair.second - pair.first, 0),
868 absl::MakeInt128(pair.second, 0) - absl::MakeInt128(pair.first, 0));
869 EXPECT_EQ(
870 absl::MakeInt128(pair.first - pair.second, 0),
871 absl::MakeInt128(pair.first, 0) -= absl::MakeInt128(pair.second, 0));
872 }
873
874 // check positive carry
875 EXPECT_EQ(absl::MakeInt128(31, 0),
876 absl::MakeInt128(20, 1) +
877 absl::MakeInt128(10, std::numeric_limits<uint64_t>::max()));
878 }
879
TEST(Int128,IncrementDecrementTest)880 TEST(Int128, IncrementDecrementTest) {
881 absl::int128 value = 0;
882 EXPECT_EQ(0, value++);
883 EXPECT_EQ(1, value);
884 EXPECT_EQ(1, value--);
885 EXPECT_EQ(0, value);
886 EXPECT_EQ(-1, --value);
887 EXPECT_EQ(-1, value);
888 EXPECT_EQ(0, ++value);
889 EXPECT_EQ(0, value);
890 }
891
TEST(Int128,MultiplicationTest)892 TEST(Int128, MultiplicationTest) {
893 // 1 bit x 1 bit, and negative combinations
894 for (int i = 0; i < 64; ++i) {
895 for (int j = 0; j < 127 - i; ++j) {
896 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
897 absl::int128 a = absl::int128(1) << i;
898 absl::int128 b = absl::int128(1) << j;
899 absl::int128 c = absl::int128(1) << (i + j);
900
901 EXPECT_EQ(c, a * b);
902 EXPECT_EQ(-c, -a * b);
903 EXPECT_EQ(-c, a * -b);
904 EXPECT_EQ(c, -a * -b);
905
906 EXPECT_EQ(c, absl::int128(a) *= b);
907 EXPECT_EQ(-c, absl::int128(-a) *= b);
908 EXPECT_EQ(-c, absl::int128(a) *= -b);
909 EXPECT_EQ(c, absl::int128(-a) *= -b);
910 }
911 }
912
913 // Pairs of random values that will not overflow signed 64-bit multiplication
914 std::pair<int64_t, int64_t> small_values[] = {
915 {0x5e61, 0xf29f79ca14b4}, // +, +
916 {0x3e033b, -0x612c0ee549}, // +, -
917 {-0x052ce7e8, 0x7c728f0f}, // -, +
918 {-0x3af7054626, -0xfb1e1d}, // -, -
919 };
920 for (const std::pair<int64_t, int64_t>& pair : small_values) {
921 SCOPED_TRACE(::testing::Message()
922 << "pair = {" << pair.first << ", " << pair.second << '}');
923
924 EXPECT_EQ(absl::int128(pair.first * pair.second),
925 absl::int128(pair.first) * absl::int128(pair.second));
926 EXPECT_EQ(absl::int128(pair.first * pair.second),
927 absl::int128(pair.first) *= absl::int128(pair.second));
928
929 EXPECT_EQ(absl::MakeInt128(pair.first * pair.second, 0),
930 absl::MakeInt128(pair.first, 0) * absl::int128(pair.second));
931 EXPECT_EQ(absl::MakeInt128(pair.first * pair.second, 0),
932 absl::MakeInt128(pair.first, 0) *= absl::int128(pair.second));
933 }
934
935 // Pairs of positive random values that will not overflow 64-bit
936 // multiplication and can be left shifted by 32 without overflow
937 std::pair<int64_t, int64_t> small_values2[] = {
938 {0x1bb0a110, 0x31487671},
939 {0x4792784e, 0x28add7d7},
940 {0x7b66553a, 0x11dff8ef},
941 };
942 for (const std::pair<int64_t, int64_t>& pair : small_values2) {
943 SCOPED_TRACE(::testing::Message()
944 << "pair = {" << pair.first << ", " << pair.second << '}');
945
946 absl::int128 a = absl::int128(pair.first << 32);
947 absl::int128 b = absl::int128(pair.second << 32);
948 absl::int128 c = absl::MakeInt128(pair.first * pair.second, 0);
949
950 EXPECT_EQ(c, a * b);
951 EXPECT_EQ(-c, -a * b);
952 EXPECT_EQ(-c, a * -b);
953 EXPECT_EQ(c, -a * -b);
954
955 EXPECT_EQ(c, absl::int128(a) *= b);
956 EXPECT_EQ(-c, absl::int128(-a) *= b);
957 EXPECT_EQ(-c, absl::int128(a) *= -b);
958 EXPECT_EQ(c, absl::int128(-a) *= -b);
959 }
960
961 // check 0, 1, and -1 behavior with large values
962 absl::int128 large_values[] = {
963 {absl::MakeInt128(0xd66f061af02d0408, 0x727d2846cb475b53)},
964 {absl::MakeInt128(0x27b8d5ed6104452d, 0x03f8a33b0ee1df4f)},
965 {-absl::MakeInt128(0x621b6626b9e8d042, 0x27311ac99df00938)},
966 {-absl::MakeInt128(0x34e0656f1e95fb60, 0x4281cfd731257a47)},
967 };
968 for (absl::int128 value : large_values) {
969 EXPECT_EQ(0, 0 * value);
970 EXPECT_EQ(0, value * 0);
971 EXPECT_EQ(0, absl::int128(0) *= value);
972 EXPECT_EQ(0, value *= 0);
973
974 EXPECT_EQ(value, 1 * value);
975 EXPECT_EQ(value, value * 1);
976 EXPECT_EQ(value, absl::int128(1) *= value);
977 EXPECT_EQ(value, value *= 1);
978
979 EXPECT_EQ(-value, -1 * value);
980 EXPECT_EQ(-value, value * -1);
981 EXPECT_EQ(-value, absl::int128(-1) *= value);
982 EXPECT_EQ(-value, value *= -1);
983 }
984
985 // Manually calculated random large value cases
986 EXPECT_EQ(absl::MakeInt128(0xcd0efd3442219bb, 0xde47c05bcd9df6e1),
987 absl::MakeInt128(0x7c6448, 0x3bc4285c47a9d253) * 0x1a6037537b);
988 EXPECT_EQ(-absl::MakeInt128(0x1f8f149850b1e5e6, 0x1e50d6b52d272c3e),
989 -absl::MakeInt128(0x23, 0x2e68a513ca1b8859) * 0xe5a434cd14866e);
990 EXPECT_EQ(-absl::MakeInt128(0x55cae732029d1fce, 0xca6474b6423263e4),
991 0xa9b98a8ddf66bc * -absl::MakeInt128(0x81, 0x672e58231e2469d7));
992 EXPECT_EQ(absl::MakeInt128(0x19c8b7620b507dc4, 0xfec042b71a5f29a4),
993 -0x3e39341147 * -absl::MakeInt128(0x6a14b2, 0x5ed34cca42327b3c));
994
995 EXPECT_EQ(absl::MakeInt128(0xcd0efd3442219bb, 0xde47c05bcd9df6e1),
996 absl::MakeInt128(0x7c6448, 0x3bc4285c47a9d253) *= 0x1a6037537b);
997 EXPECT_EQ(-absl::MakeInt128(0x1f8f149850b1e5e6, 0x1e50d6b52d272c3e),
998 -absl::MakeInt128(0x23, 0x2e68a513ca1b8859) *= 0xe5a434cd14866e);
999 EXPECT_EQ(-absl::MakeInt128(0x55cae732029d1fce, 0xca6474b6423263e4),
1000 absl::int128(0xa9b98a8ddf66bc) *=
1001 -absl::MakeInt128(0x81, 0x672e58231e2469d7));
1002 EXPECT_EQ(absl::MakeInt128(0x19c8b7620b507dc4, 0xfec042b71a5f29a4),
1003 absl::int128(-0x3e39341147) *=
1004 -absl::MakeInt128(0x6a14b2, 0x5ed34cca42327b3c));
1005 }
1006
TEST(Int128,DivisionAndModuloTest)1007 TEST(Int128, DivisionAndModuloTest) {
1008 // Check against 64 bit division and modulo operators with a sample of
1009 // randomly generated pairs.
1010 std::pair<int64_t, int64_t> small_pairs[] = {
1011 {0x15f2a64138, 0x67da05}, {0x5e56d194af43045f, 0xcf1543fb99},
1012 {0x15e61ed052036a, -0xc8e6}, {0x88125a341e85, -0xd23fb77683},
1013 {-0xc06e20, 0x5a}, {-0x4f100219aea3e85d, 0xdcc56cb4efe993},
1014 {-0x168d629105, -0xa7}, {-0x7b44e92f03ab2375, -0x6516},
1015 };
1016 for (const std::pair<int64_t, int64_t>& pair : small_pairs) {
1017 SCOPED_TRACE(::testing::Message()
1018 << "pair = {" << pair.first << ", " << pair.second << '}');
1019
1020 absl::int128 dividend = pair.first;
1021 absl::int128 divisor = pair.second;
1022 int64_t quotient = pair.first / pair.second;
1023 int64_t remainder = pair.first % pair.second;
1024
1025 EXPECT_EQ(quotient, dividend / divisor);
1026 EXPECT_EQ(quotient, absl::int128(dividend) /= divisor);
1027 EXPECT_EQ(remainder, dividend % divisor);
1028 EXPECT_EQ(remainder, absl::int128(dividend) %= divisor);
1029 }
1030
1031 // Test behavior with 0, 1, and -1 with a sample of randomly generated large
1032 // values.
1033 absl::int128 values[] = {
1034 absl::MakeInt128(0x63d26ee688a962b2, 0x9e1411abda5c1d70),
1035 absl::MakeInt128(0x152f385159d6f986, 0xbf8d48ef63da395d),
1036 -absl::MakeInt128(0x3098d7567030038c, 0x14e7a8a098dc2164),
1037 -absl::MakeInt128(0x49a037aca35c809f, 0xa6a87525480ef330),
1038 };
1039 for (absl::int128 value : values) {
1040 SCOPED_TRACE(::testing::Message() << "value = " << value);
1041
1042 EXPECT_EQ(0, 0 / value);
1043 EXPECT_EQ(0, absl::int128(0) /= value);
1044 EXPECT_EQ(0, 0 % value);
1045 EXPECT_EQ(0, absl::int128(0) %= value);
1046
1047 EXPECT_EQ(value, value / 1);
1048 EXPECT_EQ(value, absl::int128(value) /= 1);
1049 EXPECT_EQ(0, value % 1);
1050 EXPECT_EQ(0, absl::int128(value) %= 1);
1051
1052 EXPECT_EQ(-value, value / -1);
1053 EXPECT_EQ(-value, absl::int128(value) /= -1);
1054 EXPECT_EQ(0, value % -1);
1055 EXPECT_EQ(0, absl::int128(value) %= -1);
1056 }
1057
1058 // Min and max values
1059 EXPECT_EQ(0, absl::Int128Max() / absl::Int128Min());
1060 EXPECT_EQ(absl::Int128Max(), absl::Int128Max() % absl::Int128Min());
1061 EXPECT_EQ(-1, absl::Int128Min() / absl::Int128Max());
1062 EXPECT_EQ(-1, absl::Int128Min() % absl::Int128Max());
1063
1064 // Power of two division and modulo of random large dividends
1065 absl::int128 positive_values[] = {
1066 absl::MakeInt128(0x21e1a1cc69574620, 0xe7ac447fab2fc869),
1067 absl::MakeInt128(0x32c2ff3ab89e66e8, 0x03379a613fd1ce74),
1068 absl::MakeInt128(0x6f32ca786184dcaf, 0x046f9c9ecb3a9ce1),
1069 absl::MakeInt128(0x1aeb469dd990e0ee, 0xda2740f243cd37eb),
1070 };
1071 for (absl::int128 value : positive_values) {
1072 for (int i = 0; i < 127; ++i) {
1073 SCOPED_TRACE(::testing::Message()
1074 << "value = " << value << "; i = " << i);
1075 absl::int128 power_of_two = absl::int128(1) << i;
1076
1077 EXPECT_EQ(value >> i, value / power_of_two);
1078 EXPECT_EQ(value >> i, absl::int128(value) /= power_of_two);
1079 EXPECT_EQ(value & (power_of_two - 1), value % power_of_two);
1080 EXPECT_EQ(value & (power_of_two - 1),
1081 absl::int128(value) %= power_of_two);
1082 }
1083 }
1084
1085 // Manually calculated cases with random large dividends
1086 struct DivisionModCase {
1087 absl::int128 dividend;
1088 absl::int128 divisor;
1089 absl::int128 quotient;
1090 absl::int128 remainder;
1091 };
1092 DivisionModCase manual_cases[] = {
1093 {absl::MakeInt128(0x6ada48d489007966, 0x3c9c5c98150d5d69),
1094 absl::MakeInt128(0x8bc308fb, 0x8cb9cc9a3b803344), 0xc3b87e08,
1095 absl::MakeInt128(0x1b7db5e1, 0xd9eca34b7af04b49)},
1096 {absl::MakeInt128(0xd6946511b5b, 0x4886c5c96546bf5f),
1097 -absl::MakeInt128(0x263b, 0xfd516279efcfe2dc), -0x59cbabf0,
1098 absl::MakeInt128(0x622, 0xf462909155651d1f)},
1099 {-absl::MakeInt128(0x33db734f9e8d1399, 0x8447ac92482bca4d), 0x37495078240,
1100 -absl::MakeInt128(0xf01f1, 0xbc0368bf9a77eae8), -0x21a508f404d},
1101 {-absl::MakeInt128(0x13f837b409a07e7d, 0x7fc8e248a7d73560), -0x1b9f,
1102 absl::MakeInt128(0xb9157556d724, 0xb14f635714d7563e), -0x1ade},
1103 };
1104 for (const DivisionModCase test_case : manual_cases) {
1105 EXPECT_EQ(test_case.quotient, test_case.dividend / test_case.divisor);
1106 EXPECT_EQ(test_case.quotient,
1107 absl::int128(test_case.dividend) /= test_case.divisor);
1108 EXPECT_EQ(test_case.remainder, test_case.dividend % test_case.divisor);
1109 EXPECT_EQ(test_case.remainder,
1110 absl::int128(test_case.dividend) %= test_case.divisor);
1111 }
1112 }
1113
TEST(Int128,BitwiseLogicTest)1114 TEST(Int128, BitwiseLogicTest) {
1115 EXPECT_EQ(absl::int128(-1), ~absl::int128(0));
1116
1117 absl::int128 values[]{
1118 0, -1, 0xde400bee05c3ff6b, absl::MakeInt128(0x7f32178dd81d634a, 0),
1119 absl::MakeInt128(0xaf539057055613a9, 0x7d104d7d946c2e4d)};
1120 for (absl::int128 value : values) {
1121 EXPECT_EQ(value, ~~value);
1122
1123 EXPECT_EQ(value, value | value);
1124 EXPECT_EQ(value, value & value);
1125 EXPECT_EQ(0, value ^ value);
1126
1127 EXPECT_EQ(value, absl::int128(value) |= value);
1128 EXPECT_EQ(value, absl::int128(value) &= value);
1129 EXPECT_EQ(0, absl::int128(value) ^= value);
1130
1131 EXPECT_EQ(value, value | 0);
1132 EXPECT_EQ(0, value & 0);
1133 EXPECT_EQ(value, value ^ 0);
1134
1135 EXPECT_EQ(absl::int128(-1), value | absl::int128(-1));
1136 EXPECT_EQ(value, value & absl::int128(-1));
1137 EXPECT_EQ(~value, value ^ absl::int128(-1));
1138 }
1139
1140 // small sample of randomly generated int64_t's
1141 std::pair<int64_t, int64_t> pairs64[]{
1142 {0x7f86797f5e991af4, 0x1ee30494fb007c97},
1143 {0x0b278282bacf01af, 0x58780e0a57a49e86},
1144 {0x059f266ccb93a666, 0x3d5b731bae9286f5},
1145 {0x63c0c4820f12108c, 0x58166713c12e1c3a},
1146 {0x381488bb2ed2a66e, 0x2220a3eb76a3698c},
1147 {0x2a0a0dfb81e06f21, 0x4b60585927f5523c},
1148 {0x555b1c3a03698537, 0x25478cd19d8e53cb},
1149 {0x4750f6f27d779225, 0x16397553c6ff05fc},
1150 };
1151 for (const std::pair<int64_t, int64_t>& pair : pairs64) {
1152 SCOPED_TRACE(::testing::Message()
1153 << "pair = {" << pair.first << ", " << pair.second << '}');
1154
1155 EXPECT_EQ(absl::MakeInt128(~pair.first, ~pair.second),
1156 ~absl::MakeInt128(pair.first, pair.second));
1157
1158 EXPECT_EQ(absl::int128(pair.first & pair.second),
1159 absl::int128(pair.first) & absl::int128(pair.second));
1160 EXPECT_EQ(absl::int128(pair.first | pair.second),
1161 absl::int128(pair.first) | absl::int128(pair.second));
1162 EXPECT_EQ(absl::int128(pair.first ^ pair.second),
1163 absl::int128(pair.first) ^ absl::int128(pair.second));
1164
1165 EXPECT_EQ(absl::int128(pair.first & pair.second),
1166 absl::int128(pair.first) &= absl::int128(pair.second));
1167 EXPECT_EQ(absl::int128(pair.first | pair.second),
1168 absl::int128(pair.first) |= absl::int128(pair.second));
1169 EXPECT_EQ(absl::int128(pair.first ^ pair.second),
1170 absl::int128(pair.first) ^= absl::int128(pair.second));
1171
1172 EXPECT_EQ(
1173 absl::MakeInt128(pair.first & pair.second, 0),
1174 absl::MakeInt128(pair.first, 0) & absl::MakeInt128(pair.second, 0));
1175 EXPECT_EQ(
1176 absl::MakeInt128(pair.first | pair.second, 0),
1177 absl::MakeInt128(pair.first, 0) | absl::MakeInt128(pair.second, 0));
1178 EXPECT_EQ(
1179 absl::MakeInt128(pair.first ^ pair.second, 0),
1180 absl::MakeInt128(pair.first, 0) ^ absl::MakeInt128(pair.second, 0));
1181
1182 EXPECT_EQ(
1183 absl::MakeInt128(pair.first & pair.second, 0),
1184 absl::MakeInt128(pair.first, 0) &= absl::MakeInt128(pair.second, 0));
1185 EXPECT_EQ(
1186 absl::MakeInt128(pair.first | pair.second, 0),
1187 absl::MakeInt128(pair.first, 0) |= absl::MakeInt128(pair.second, 0));
1188 EXPECT_EQ(
1189 absl::MakeInt128(pair.first ^ pair.second, 0),
1190 absl::MakeInt128(pair.first, 0) ^= absl::MakeInt128(pair.second, 0));
1191 }
1192 }
1193
TEST(Int128,BitwiseShiftTest)1194 TEST(Int128, BitwiseShiftTest) {
1195 for (int i = 0; i < 64; ++i) {
1196 for (int j = 0; j <= i; ++j) {
1197 // Left shift from j-th bit to i-th bit.
1198 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
1199 EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) << (i - j));
1200 EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) <<= (i - j));
1201 }
1202 }
1203 for (int i = 0; i < 63; ++i) {
1204 for (int j = 0; j < 64; ++j) {
1205 // Left shift from j-th bit to (i + 64)-th bit.
1206 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
1207 EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
1208 absl::int128(uint64_t{1} << j) << (i + 64 - j));
1209 EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
1210 absl::int128(uint64_t{1} << j) <<= (i + 64 - j));
1211 }
1212 for (int j = 0; j <= i; ++j) {
1213 // Left shift from (j + 64)-th bit to (i + 64)-th bit.
1214 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
1215 EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
1216 absl::MakeInt128(uint64_t{1} << j, 0) << (i - j));
1217 EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
1218 absl::MakeInt128(uint64_t{1} << j, 0) <<= (i - j));
1219 }
1220 }
1221
1222 for (int i = 0; i < 64; ++i) {
1223 for (int j = i; j < 64; ++j) {
1224 // Right shift from j-th bit to i-th bit.
1225 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
1226 EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) >> (j - i));
1227 EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) >>= (j - i));
1228 }
1229 for (int j = 0; j < 63; ++j) {
1230 // Right shift from (j + 64)-th bit to i-th bit.
1231 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
1232 EXPECT_EQ(uint64_t{1} << i,
1233 absl::MakeInt128(uint64_t{1} << j, 0) >> (j + 64 - i));
1234 EXPECT_EQ(uint64_t{1} << i,
1235 absl::MakeInt128(uint64_t{1} << j, 0) >>= (j + 64 - i));
1236 }
1237 }
1238 for (int i = 0; i < 63; ++i) {
1239 for (int j = i; j < 63; ++j) {
1240 // Right shift from (j + 64)-th bit to (i + 64)-th bit.
1241 SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
1242 EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
1243 absl::MakeInt128(uint64_t{1} << j, 0) >> (j - i));
1244 EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
1245 absl::MakeInt128(uint64_t{1} << j, 0) >>= (j - i));
1246 }
1247 }
1248 }
1249
TEST(Int128,NumericLimitsTest)1250 TEST(Int128, NumericLimitsTest) {
1251 static_assert(std::numeric_limits<absl::int128>::is_specialized, "");
1252 static_assert(std::numeric_limits<absl::int128>::is_signed, "");
1253 static_assert(std::numeric_limits<absl::int128>::is_integer, "");
1254 EXPECT_EQ(static_cast<int>(127 * std::log10(2)),
1255 std::numeric_limits<absl::int128>::digits10);
1256 EXPECT_EQ(absl::Int128Min(), std::numeric_limits<absl::int128>::min());
1257 EXPECT_EQ(absl::Int128Min(), std::numeric_limits<absl::int128>::lowest());
1258 EXPECT_EQ(absl::Int128Max(), std::numeric_limits<absl::int128>::max());
1259 }
1260
1261 } // namespace
1262