Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 1 | //===-------------------------- hash.cpp ----------------------------------===// |
| 2 | // |
Howard Hinnant | f5256e1 | 2010-05-11 21:36:01 +0000 | [diff] [blame] | 3 | // The LLVM Compiler Infrastructure |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 4 | // |
Howard Hinnant | b64f8b0 | 2010-11-16 22:09:02 +0000 | [diff] [blame] | 5 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 6 | // Source Licenses. See LICENSE.TXT for details. |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | |
| 10 | #include "__hash_table" |
| 11 | #include "algorithm" |
Howard Hinnant | e87ad17 | 2010-10-29 14:10:30 +0000 | [diff] [blame] | 12 | #include "stdexcept" |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 13 | |
| 14 | _LIBCPP_BEGIN_NAMESPACE_STD |
| 15 | |
| 16 | namespace { |
| 17 | |
| 18 | // handle all next_prime(i) for i in [1, 210), special case 0 |
| 19 | const unsigned small_primes[] = |
| 20 | { |
| 21 | 0, |
| 22 | 2, |
| 23 | 3, |
| 24 | 5, |
| 25 | 7, |
| 26 | 11, |
| 27 | 13, |
| 28 | 17, |
| 29 | 19, |
| 30 | 23, |
| 31 | 29, |
| 32 | 31, |
| 33 | 37, |
| 34 | 41, |
| 35 | 43, |
| 36 | 47, |
| 37 | 53, |
| 38 | 59, |
| 39 | 61, |
| 40 | 67, |
| 41 | 71, |
| 42 | 73, |
| 43 | 79, |
| 44 | 83, |
| 45 | 89, |
| 46 | 97, |
| 47 | 101, |
| 48 | 103, |
| 49 | 107, |
| 50 | 109, |
| 51 | 113, |
| 52 | 127, |
| 53 | 131, |
| 54 | 137, |
| 55 | 139, |
| 56 | 149, |
| 57 | 151, |
| 58 | 157, |
| 59 | 163, |
| 60 | 167, |
| 61 | 173, |
| 62 | 179, |
| 63 | 181, |
| 64 | 191, |
| 65 | 193, |
| 66 | 197, |
| 67 | 199, |
| 68 | 211 |
| 69 | }; |
| 70 | |
| 71 | // potential primes = 210*k + indices[i], k >= 1 |
| 72 | // these numbers are not divisible by 2, 3, 5 or 7 |
| 73 | // (or any integer 2 <= j <= 10 for that matter). |
| 74 | const unsigned indices[] = |
| 75 | { |
| 76 | 1, |
| 77 | 11, |
| 78 | 13, |
| 79 | 17, |
| 80 | 19, |
| 81 | 23, |
| 82 | 29, |
| 83 | 31, |
| 84 | 37, |
| 85 | 41, |
| 86 | 43, |
| 87 | 47, |
| 88 | 53, |
| 89 | 59, |
| 90 | 61, |
| 91 | 67, |
| 92 | 71, |
| 93 | 73, |
| 94 | 79, |
| 95 | 83, |
| 96 | 89, |
| 97 | 97, |
| 98 | 101, |
| 99 | 103, |
| 100 | 107, |
| 101 | 109, |
| 102 | 113, |
| 103 | 121, |
| 104 | 127, |
| 105 | 131, |
| 106 | 137, |
| 107 | 139, |
| 108 | 143, |
| 109 | 149, |
| 110 | 151, |
| 111 | 157, |
| 112 | 163, |
| 113 | 167, |
| 114 | 169, |
| 115 | 173, |
| 116 | 179, |
| 117 | 181, |
| 118 | 187, |
| 119 | 191, |
| 120 | 193, |
| 121 | 197, |
| 122 | 199, |
| 123 | 209 |
| 124 | }; |
| 125 | |
| 126 | } |
| 127 | |
| 128 | // Returns: If n == 0, returns 0. Else returns the lowest prime number that |
| 129 | // is greater than or equal to n. |
Howard Hinnant | 16e6e1d | 2010-08-22 00:03:27 +0000 | [diff] [blame] | 130 | // |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 131 | // The algorithm creates a list of small primes, plus an open-ended list of |
| 132 | // potential primes. All prime numbers are potential prime numbers. However |
| 133 | // some potential prime numbers are not prime. In an ideal world, all potential |
| 134 | // prime numbers would be prime. Candiate prime numbers are chosen as the next |
| 135 | // highest potential prime. Then this number is tested for prime by dividing it |
| 136 | // by all potential prime numbers less than the sqrt of the candidate. |
Howard Hinnant | 16e6e1d | 2010-08-22 00:03:27 +0000 | [diff] [blame] | 137 | // |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 138 | // This implementation defines potential primes as those numbers not divisible |
| 139 | // by 2, 3, 5, and 7. Other (common) implementations define potential primes |
| 140 | // as those not divisible by 2. A few other implementations define potential |
| 141 | // primes as those not divisible by 2 or 3. By raising the number of small |
| 142 | // primes which the potential prime is not divisible by, the set of potential |
| 143 | // primes more closely approximates the set of prime numbers. And thus there |
| 144 | // are fewer potential primes to search, and fewer potential primes to divide |
| 145 | // against. |
| 146 | |
Howard Hinnant | e87ad17 | 2010-10-29 14:10:30 +0000 | [diff] [blame] | 147 | inline _LIBCPP_INLINE_VISIBILITY |
| 148 | void |
| 149 | __check_for_overflow(size_t N, integral_constant<size_t, 32>) |
| 150 | { |
| 151 | #ifndef _LIBCPP_NO_EXCEPTIONS |
| 152 | if (N > 0xFFFFFFFB) |
| 153 | throw overflow_error("__next_prime overflow"); |
| 154 | #endif |
| 155 | } |
| 156 | |
| 157 | inline _LIBCPP_INLINE_VISIBILITY |
| 158 | void |
| 159 | __check_for_overflow(size_t N, integral_constant<size_t, 64>) |
| 160 | { |
| 161 | #ifndef _LIBCPP_NO_EXCEPTIONS |
| 162 | if (N > 0xFFFFFFFFFFFFFFC5ull) |
| 163 | throw overflow_error("__next_prime overflow"); |
| 164 | #endif |
| 165 | } |
| 166 | |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 167 | size_t |
| 168 | __next_prime(size_t n) |
| 169 | { |
| 170 | const size_t L = 210; |
| 171 | const size_t N = sizeof(small_primes) / sizeof(small_primes[0]); |
| 172 | // If n is small enough, search in small_primes |
| 173 | if (n <= small_primes[N-1]) |
| 174 | return *std::lower_bound(small_primes, small_primes + N, n); |
| 175 | // Else n > largest small_primes |
Howard Hinnant | e87ad17 | 2010-10-29 14:10:30 +0000 | [diff] [blame] | 176 | // Check for overflow |
| 177 | __check_for_overflow(n, integral_constant<size_t, |
| 178 | sizeof(n) * __CHAR_BIT__>()); |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 179 | // Start searching list of potential primes: L * k0 + indices[in] |
| 180 | const size_t M = sizeof(indices) / sizeof(indices[0]); |
| 181 | // Select first potential prime >= n |
| 182 | // Known a-priori n >= L |
| 183 | size_t k0 = n / L; |
Howard Hinnant | ec3773c | 2011-12-01 20:21:04 +0000 | [diff] [blame] | 184 | size_t in = static_cast<size_t>(std::lower_bound(indices, indices + M, n - k0 * L) |
| 185 | - indices); |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 186 | n = L * k0 + indices[in]; |
| 187 | while (true) |
| 188 | { |
| 189 | // Divide n by all primes or potential primes (i) until: |
| 190 | // 1. The division is even, so try next potential prime. |
| 191 | // 2. The i > sqrt(n), in which case n is prime. |
| 192 | // It is known a-priori that n is not divisible by 2, 3, 5 or 7, |
| 193 | // so don't test those (j == 5 -> divide by 11 first). And the |
| 194 | // potential primes start with 211, so don't test against the last |
| 195 | // small prime. |
| 196 | for (size_t j = 5; j < N - 1; ++j) |
| 197 | { |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 198 | const std::size_t p = small_primes[j]; |
| 199 | const std::size_t q = n / p; |
| 200 | if (q < p) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 201 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 202 | if (n == q * p) |
| 203 | goto next; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 204 | } |
| 205 | // n wasn't divisible by small primes, try potential primes |
| 206 | { |
| 207 | size_t i = 211; |
| 208 | while (true) |
| 209 | { |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 210 | std::size_t q = n / i; |
| 211 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 212 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 213 | if (n == q * i) |
| 214 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 215 | |
| 216 | i += 10; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 217 | q = n / i; |
| 218 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 219 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 220 | if (n == q * i) |
| 221 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 222 | |
| 223 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 224 | q = n / i; |
| 225 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 226 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 227 | if (n == q * i) |
| 228 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 229 | |
| 230 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 231 | q = n / i; |
| 232 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 233 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 234 | if (n == q * i) |
| 235 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 236 | |
| 237 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 238 | q = n / i; |
| 239 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 240 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 241 | if (n == q * i) |
| 242 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 243 | |
| 244 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 245 | q = n / i; |
| 246 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 247 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 248 | if (n == q * i) |
| 249 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 250 | |
| 251 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 252 | q = n / i; |
| 253 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 254 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 255 | if (n == q * i) |
| 256 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 257 | |
| 258 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 259 | q = n / i; |
| 260 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 261 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 262 | if (n == q * i) |
| 263 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 264 | |
| 265 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 266 | q = n / i; |
| 267 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 268 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 269 | if (n == q * i) |
| 270 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 271 | |
| 272 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 273 | q = n / i; |
| 274 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 275 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 276 | if (n == q * i) |
| 277 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 278 | |
| 279 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 280 | q = n / i; |
| 281 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 282 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 283 | if (n == q * i) |
| 284 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 285 | |
| 286 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 287 | q = n / i; |
| 288 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 289 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 290 | if (n == q * i) |
| 291 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 292 | |
| 293 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 294 | q = n / i; |
| 295 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 296 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 297 | if (n == q * i) |
| 298 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 299 | |
| 300 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 301 | q = n / i; |
| 302 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 303 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 304 | if (n == q * i) |
| 305 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 306 | |
| 307 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 308 | q = n / i; |
| 309 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 310 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 311 | if (n == q * i) |
| 312 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 313 | |
| 314 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 315 | q = n / i; |
| 316 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 317 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 318 | if (n == q * i) |
| 319 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 320 | |
| 321 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 322 | q = n / i; |
| 323 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 324 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 325 | if (n == q * i) |
| 326 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 327 | |
| 328 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 329 | q = n / i; |
| 330 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 331 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 332 | if (n == q * i) |
| 333 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 334 | |
| 335 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 336 | q = n / i; |
| 337 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 338 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 339 | if (n == q * i) |
| 340 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 341 | |
| 342 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 343 | q = n / i; |
| 344 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 345 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 346 | if (n == q * i) |
| 347 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 348 | |
| 349 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 350 | q = n / i; |
| 351 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 352 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 353 | if (n == q * i) |
| 354 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 355 | |
| 356 | i += 8; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 357 | q = n / i; |
| 358 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 359 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 360 | if (n == q * i) |
| 361 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 362 | |
| 363 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 364 | q = n / i; |
| 365 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 366 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 367 | if (n == q * i) |
| 368 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 369 | |
| 370 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 371 | q = n / i; |
| 372 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 373 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 374 | if (n == q * i) |
| 375 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 376 | |
| 377 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 378 | q = n / i; |
| 379 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 380 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 381 | if (n == q * i) |
| 382 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 383 | |
| 384 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 385 | q = n / i; |
| 386 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 387 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 388 | if (n == q * i) |
| 389 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 390 | |
| 391 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 392 | q = n / i; |
| 393 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 394 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 395 | if (n == q * i) |
| 396 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 397 | |
| 398 | i += 8; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 399 | q = n / i; |
| 400 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 401 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 402 | if (n == q * i) |
| 403 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 404 | |
| 405 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 406 | q = n / i; |
| 407 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 408 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 409 | if (n == q * i) |
| 410 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 411 | |
| 412 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 413 | q = n / i; |
| 414 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 415 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 416 | if (n == q * i) |
| 417 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 418 | |
| 419 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 420 | q = n / i; |
| 421 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 422 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 423 | if (n == q * i) |
| 424 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 425 | |
| 426 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 427 | q = n / i; |
| 428 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 429 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 430 | if (n == q * i) |
| 431 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 432 | |
| 433 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 434 | q = n / i; |
| 435 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 436 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 437 | if (n == q * i) |
| 438 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 439 | |
| 440 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 441 | q = n / i; |
| 442 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 443 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 444 | if (n == q * i) |
| 445 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 446 | |
| 447 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 448 | q = n / i; |
| 449 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 450 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 451 | if (n == q * i) |
| 452 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 453 | |
| 454 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 455 | q = n / i; |
| 456 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 457 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 458 | if (n == q * i) |
| 459 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 460 | |
| 461 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 462 | q = n / i; |
| 463 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 464 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 465 | if (n == q * i) |
| 466 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 467 | |
| 468 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 469 | q = n / i; |
| 470 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 471 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 472 | if (n == q * i) |
| 473 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 474 | |
| 475 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 476 | q = n / i; |
| 477 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 478 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 479 | if (n == q * i) |
| 480 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 481 | |
| 482 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 483 | q = n / i; |
| 484 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 485 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 486 | if (n == q * i) |
| 487 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 488 | |
| 489 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 490 | q = n / i; |
| 491 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 492 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 493 | if (n == q * i) |
| 494 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 495 | |
| 496 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 497 | q = n / i; |
| 498 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 499 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 500 | if (n == q * i) |
| 501 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 502 | |
| 503 | i += 6; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 504 | q = n / i; |
| 505 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 506 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 507 | if (n == q * i) |
| 508 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 509 | |
| 510 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 511 | q = n / i; |
| 512 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 513 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 514 | if (n == q * i) |
| 515 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 516 | |
| 517 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 518 | q = n / i; |
| 519 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 520 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 521 | if (n == q * i) |
| 522 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 523 | |
| 524 | i += 4; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 525 | q = n / i; |
| 526 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 527 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 528 | if (n == q * i) |
| 529 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 530 | |
| 531 | i += 2; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 532 | q = n / i; |
| 533 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 534 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 535 | if (n == q * i) |
| 536 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 537 | |
| 538 | i += 10; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 539 | q = n / i; |
| 540 | if (q < i) |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 541 | return n; |
Howard Hinnant | d2a9251 | 2010-09-13 01:43:27 +0000 | [diff] [blame] | 542 | if (n == q * i) |
| 543 | break; |
Howard Hinnant | bc8d3f9 | 2010-05-11 19:42:16 +0000 | [diff] [blame] | 544 | |
| 545 | // This will loop i to the next "plane" of potential primes |
| 546 | i += 2; |
| 547 | } |
| 548 | } |
| 549 | next: |
| 550 | // n is not prime. Increment n to next potential prime. |
| 551 | if (++in == M) |
| 552 | { |
| 553 | ++k0; |
| 554 | in = 0; |
| 555 | } |
| 556 | n = L * k0 + indices[in]; |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | _LIBCPP_END_NAMESPACE_STD |