contrib/gmp/randmt.c

   1 /* Mersenne Twister pseudo-random number generator functions.
   2
   3    THE FUNCTIONS IN THIS FILE ARE FOR INTERNAL USE ONLY.  THEY'RE ALMOST
   4    CERTAIN TO BE SUBJECT TO INCOMPATIBLE CHANGES OR DISAPPEAR COMPLETELY IN
   5    FUTURE GNU MP RELEASES.
   6
   7 Copyright 2002, 2003, 2006 Free Software Foundation, Inc.
   8
   9 This file is part of the GNU MP Library.
  10
  11 The GNU MP Library is free software; you can redistribute it and/or modify
  12 it under the terms of the GNU Lesser General Public License as published by
  13 the Free Software Foundation; either version 3 of the License, or (at your
  14 option) any later version.
  15
  16 The GNU MP Library is distributed in the hope that it will be useful, but
  17 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  18 or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  19 License for more details.
  20
  21 You should have received a copy of the GNU Lesser General Public License
  22 along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
  23
  24 #include <stdio.h>   /* for NULL */
  25
  26 #include "gmp.h"
  27 #include "gmp-impl.h"
  28 #include "randmt.h"
  29
  30
  31 /* This code implements the Mersenne Twister pseudorandom number generator
  32    by Takuji Nishimura and Makoto Matsumoto.  The buffer initialization
  33    function is different in order to permit seeds greater than 2^32-1.
  34
  35    This file contains a special __gmp_randinit_mt_noseed which excludes the
  36    seeding function from the gmp_randfnptr_t routines.  This is for use by
  37    mpn_random and mpn_random2 on the global random generator.  MT seeding
  38    uses mpz functions, and we don't want mpn routines dragging mpz functions
  39    into the link.  */
  40
  41
  42 /* Default seed to use when the generator is not initialized.  */
  43 #define DEFAULT_SEED 5489 /* was 4357 */
  44
  45 /* Tempering masks.  */
  46 #define MASK_1 0x9D2C5680
  47 #define MASK_2 0xEFC60000
  48
  49 /* Initial state of buffer when initialized with default seed.  */
  50 static const gmp_uint_least32_t default_state[N] =
  51 {
  52   0xD247B233,0x9E5AA8F1,0x0FFA981B,0x9DCB0980,0x74200F2B,0xA576D044,
  53   0xE9F05ADF,0x1538BFF5,0x59818BBF,0xCF9E58D8,0x09FCE032,0x6A1C663F,
  54   0x5116E78A,0x69B3E0FA,0x6D92D665,0xD0A8BE98,0xF669B734,0x41AC1B68,
  55   0x630423F1,0x4B8D6B8A,0xC2C46DD7,0x5680747D,0x43703E8F,0x3B6103D2,
  56   0x49E5EB3F,0xCBDAB4C1,0x9C988E23,0x747BEE0B,0x9111E329,0x9F031B5A,
  57   0xECCA71B9,0x2AFE4EF8,0x8421C7ED,0xAC89AFF1,0xAED90DF3,0x2DD74F01,
  58   0x14906A13,0x75873FA9,0xFF83F877,0x5028A0C9,0x11B4C41D,0x7CAEDBC4,
  59   0x8672D0A7,0x48A7C109,0x8320E59F,0xBC0B3D5F,0x75A30886,0xF9E0D128,
  60   0x41AF7580,0x239BB94D,0xC67A3C81,0x74EEBD6E,0xBC02B53C,0x727EA449,
  61   0x6B8A2806,0x5853B0DA,0xBDE032F4,0xCE234885,0x320D6145,0x48CC053F,
  62   0x00DBC4D2,0xD55A2397,0xE1059B6F,0x1C3E05D1,0x09657C64,0xD07CB661,
  63   0x6E982E34,0x6DD1D777,0xEDED1071,0xD79DFD65,0xF816DDCE,0xB6FAF1E4,
  64   0x1C771074,0x311835BD,0x18F952F7,0xF8F40350,0x4ECED354,0x7C8AC12B,
  65   0x31A9994D,0x4FD47747,0xDC227A23,0x6DFAFDDF,0x6796E748,0x0C6F634F,
  66   0xF992FA1D,0x4CF670C9,0x067DFD31,0xA7A3E1A5,0x8CD7D9DF,0x972CCB34,
  67   0x67C82156,0xD548F6A8,0x045CEC21,0xF3240BFB,0xDEF656A7,0x43DE08C5,
  68   0xDAD1F92F,0x3726C56B,0x1409F19A,0x942FD147,0xB926749C,0xADDC31B8,
  69   0x53D0D869,0xD1BA52FE,0x6722DF8C,0x22D95A74,0x7DC1B52A,0x1DEC6FD5,
  70   0x7262874D,0x0A725DC9,0xE6A8193D,0xA052835A,0xDC9AD928,0xE59EBB90,
  71   0x70DBA9FF,0xD612749D,0x5A5A638C,0x6086EC37,0x2A579709,0x1449EA3A,
  72   0xBC8E3C06,0x2F900666,0xFBE74FD1,0x6B35B911,0xF8335008,0xEF1E979D,
  73   0x738AB29D,0xA2DC0FDC,0x7696305D,0xF5429DAC,0x8C41813B,0x8073E02E,
  74   0xBEF83CCD,0x7B50A95A,0x05EE5862,0x00829ECE,0x8CA1958C,0xBE4EA2E2,
  75   0x4293BB73,0x656F7B23,0x417316D8,0x4467D7CF,0x2200E63B,0x109050C8,
  76   0x814CBE47,0x36B1D4A8,0x36AF9305,0x308327B3,0xEBCD7344,0xA738DE27,
  77   0x5A10C399,0x4142371D,0x64A18528,0x0B31E8B2,0x641057B9,0x6AFC363B,
  78   0x108AD953,0x9D4DA234,0x0C2D9159,0x1C8A1A1F,0x310C66BA,0x87AA1070,
  79   0xDAC832FF,0x0A433422,0x7AF15812,0x2D8D9BD0,0x995A25E9,0x25326CAC,
  80   0xA34384DB,0x4C8421CC,0x4F0315EC,0x29E8649E,0xA7732D6F,0x2E94D3E3,
  81   0x7D98A340,0x397C4D74,0x659DB4DE,0x747D4E9A,0xD9DB8435,0x4659DBE9,
  82   0x313E6DC5,0x29D104DC,0x9F226CBA,0x452F18B0,0xD0BC5068,0x844CA299,
  83   0x782B294E,0x4AE2EB7B,0xA4C475F8,0x70A81311,0x4B3E8BCC,0x7E20D4BA,
  84   0xABCA33C9,0x57BE2960,0x44F9B419,0x2E567746,0x72EB757A,0x102CC0E8,
  85   0xB07F32B9,0xD0DABD59,0xBA85AD6B,0xF3E20667,0x98D77D81,0x197AFA47,
  86   0x518EE9AC,0xE10CE5A2,0x01CF2C2A,0xD3A3AF3D,0x16DDFD65,0x669232F8,
  87   0x1C50A301,0xB93D9151,0x9354D3F4,0x847D79D0,0xD5FE2EC6,0x1F7B0610,
  88   0xFA6B90A5,0xC5879041,0x2E7DC05E,0x423F1F32,0xEF623DDB,0x49C13280,
  89   0x98714E92,0xC7B6E4AD,0xC4318466,0x0737F312,0x4D3C003F,0x9ACC1F1F,
  90   0x5F1C926D,0x085FA771,0x185A83A2,0xF9AA159D,0x0B0B0132,0xF98E7A43,
  91   0xCD9EBDBE,0x0190CB29,0x10D93FB6,0x3B8A4D97,0x66A65A41,0xE43E766F,
  92   0x77BE3C41,0xB9686364,0xCB36994D,0x6846A287,0x567E77F7,0x36178DD8,
  93   0xBDE6B1F2,0xB6EFDC64,0x82950324,0x42053F47,0xC09BE51C,0x0942D762,
  94   0x35F92C7F,0x367DEC61,0x6EE3D983,0xDBAAF78A,0x265D2C47,0x8EB4BF5C,
  95   0x33B232D7,0xB0137E77,0x373C39A7,0x8D2B2E76,0xC7510F01,0x50F9E032,
  96   0x7B1FDDDB,0x724C2AAE,0xB10ECB31,0xCCA3D1B8,0x7F0BCF10,0x4254BBBD,
  97   0xE3F93B97,0x2305039B,0x53120E22,0x1A2F3B9A,0x0FDDBD97,0x0118561E,
  98   0x0A798E13,0x9E0B3ACD,0xDB6C9F15,0xF512D0A2,0x9E8C3A28,0xEE2184AE,
  99   0x0051EC2F,0x2432F74F,0xB0AA66EA,0x55128D88,0xF7D83A38,0x4DAE8E82,
 100   0x3FDC98D6,0x5F0BD341,0x7244BE1D,0xC7B48E78,0x2D473053,0x43892E20,
 101   0xBA0F1F2A,0x524D4895,0x2E10BCB1,0x4C372D81,0x5C3E50CD,0xCF61CC2E,
 102   0x931709AB,0x81B3AEFC,0x39E9405E,0x7FFE108C,0x4FBB3FF8,0x06ABE450,
 103   0x7F5BF51E,0xA4E3CDFD,0xDB0F6C6F,0x159A1227,0x3B9FED55,0xD20B6F7F,
 104   0xFBE9CC83,0x64856619,0xBF52B8AF,0x9D7006B0,0x71165BC6,0xAE324AEE,
 105   0x29D27F2C,0x794C2086,0x74445CE2,0x782915CC,0xD4CE6886,0x3289AE7C,
 106   0x53DEF297,0x4185F7ED,0x88B72400,0x3C09DC11,0xBCE3AAB6,0x6A75934A,
 107   0xB267E399,0x000DF1BF,0x193BA5E2,0xFA3E1977,0x179E14F6,0x1EEDE298,
 108   0x691F0B06,0xB84F78AC,0xC1C15316,0xFFFF3AD6,0x0B457383,0x518CD612,
 109   0x05A00F3E,0xD5B7D275,0x4C5ECCD7,0xE02CD0BE,0x5558E9F2,0x0C89BBF0,
 110   0xA3D96227,0x2832D2B2,0xF667B897,0xD4556554,0xF9D2F01F,0xFA1E3FAE,
 111   0x52C2E1EE,0xE5451F31,0x7E849729,0xDABDB67A,0x54BF5E7E,0xF831C271,
 112   0x5F1A17E3,0x9D140AFE,0x92741C47,0x48CFABCE,0x9CBBE477,0x9C3EE57F,
 113   0xB07D4C39,0xCC21BCE2,0x697708B1,0x58DA2A6B,0x2370DB16,0x6E641948,
 114   0xACC5BD52,0x868F24CC,0xCA1DB0F5,0x4CADA492,0x3F443E54,0xC4A4D5E9,
 115   0xF00AD670,0xE93C86E0,0xFE90651A,0xDDE532A3,0xA66458DF,0xAB7D7151,
 116   0x0E2E775F,0xC9109F99,0x8D96D59F,0x73CEF14C,0xC74E88E9,0x02712DC0,
 117   0x04F41735,0x2E5914A2,0x59F4B2FB,0x0287FC83,0x80BC0343,0xF6B32559,
 118   0xC74178D4,0xF1D99123,0x383CCC07,0xACC0637D,0x0863A548,0xA6FCAC85,
 119   0x2A13EFF0,0xAF2EEDB1,0x41E72750,0xE0C6B342,0x5DA22B46,0x635559E0,
 120   0xD2EA40AC,0x10AA98C0,0x19096497,0x112C542B,0x2C85040C,0xA868E7D0,
 121   0x6E260188,0xF596D390,0xC3BB5D7A,0x7A2AA937,0xDFD15032,0x6780AE3B,
 122   0xDB5F9CD8,0x8BD266B0,0x7744AF12,0xB463B1B0,0x589629C9,0xE30DBC6E,
 123   0x880F5569,0x209E6E16,0x9DECA50C,0x02987A57,0xBED3EA57,0xD3A678AA,
 124   0x70DD030D,0x0CFD9C5D,0x92A18E99,0xF5740619,0x7F6F0A7D,0x134CAF9A,
 125   0x70F5BAE4,0x23DCA7B5,0x4D788FCD,0xC7F07847,0xBCF77DA1,0x9071D568,
 126   0xFC627EA1,0xAE004B77,0x66B54BCB,0x7EF2DAAC,0xDCD5AC30,0xB9BDF730,
 127   0x505A97A7,0x9D881FD3,0xADB796CC,0x94A1D202,0x97535D7F,0x31EC20C0,
 128   0xB1887A98,0xC1475069,0xA6F73AF3,0x71E4E067,0x46A569DE,0xD2ADE430,
 129   0x6F0762C7,0xF50876F4,0x53510542,0x03741C3E,0x53502224,0xD8E54D60,
 130   0x3C44AB1A,0x34972B46,0x74BFA89D,0xD7D768E0,0x37E605DC,0xE13D1BDF,
 131   0x5051C421,0xB9E057BE,0xB717A14C,0xA1730C43,0xB99638BE,0xB5D5F36D,
 132   0xE960D9EA,0x6B1388D3,0xECB6D3B6,0xBDBE8B83,0x2E29AFC5,0x764D71EC,
 133   0x4B8F4F43,0xC21DDC00,0xA63F657F,0x82678130,0xDBF535AC,0xA594FC58,
 134   0x942686BC,0xBD9B657B,0x4A0F9B61,0x44FF184F,0x38E10A2F,0x61910626,
 135   0x5E247636,0x7106D137,0xC62802F0,0xBD1D1F00,0x7CC0DCB2,0xED634909,
 136   0xDC13B24E,0x9799C499,0xD77E3D6A,0x14773B68,0x967A4FB7,0x35EECFB1,
 137   0x2A5110B8,0xE2F0AF94,0x9D09DEA5,0x20255D27,0x5771D34B,0xE1089EE4,
 138   0x246F330B,0x8F7CAEE5,0xD3064712,0x75CAFBEE,0xB94F7028,0xED953666,
 139   0x5D1975B4,0x5AF81271,0x13BE2025,0x85194659,0x30805331,0xEC9D46C0,
 140   0xBC027C36,0x2AF84188,0xC2141B80,0xC02B1E4A,0x04D36177,0xFC50E9D7,
 141   0x39CE79DA,0x917E0A00,0xEF7A0BF4,0xA98BD8D1,0x19424DD2,0x9439DF1F,
 142   0xC42AF746,0xADDBE83E,0x85221F0D,0x45563E90,0x9095EC52,0x77887B25,
 143   0x8AE46064,0xBD43B71A,0xBB541956,0x7366CF9D,0xEE8E1737,0xB5A727C9,
 144   0x5076B3E7,0xFC70BACA,0xCE135B75,0xC4E91AA3,0xF0341911,0x53430C3F,
 145   0x886B0824,0x6BB5B8B7,0x33E21254,0xF193B456,0x5B09617F,0x215FFF50,
 146   0x48D97EF1,0x356479AB,0x6EA9DDC4,0x0D352746,0xA2F5CE43,0xB226A1B3,
 147   0x1329EA3C,0x7A337CC2,0xB5CCE13D,0x563E3B5B,0x534E8E8F,0x561399C9,
 148   0xE1596392,0xB0F03125,0x4586645B,0x1F371847,0x94EAABD1,0x41F97EDD,
 149   0xE3E5A39B,0x71C774E2,0x507296F4,0x5960133B,0x7852C494,0x3F5B2691,
 150   0xA3F87774,0x5A7AF89E,0x17DA3F28,0xE9D9516D,0xFCC1C1D5,0xE4618628,
 151   0x04081047,0xD8E4DB5F,0xDC380416,0x8C4933E2,0x95074D53,0xB1B0032D,
 152   0xCC8102EA,0x71641243,0x98D6EB6A,0x90FEC945,0xA0914345,0x6FAB037D,
 153   0x70F49C4D,0x05BF5B0E,0x927AAF7F,0xA1940F61,0xFEE0756F,0xF815369F,
 154   0x5C00253B,0xF2B9762F,0x4AEB3CCC,0x1069F386,0xFBA4E7B9,0x70332665,
 155   0x6BCA810E,0x85AB8058,0xAE4B2B2F,0x9D120712,0xBEE8EACB,0x776A1112
 156 };
 157
 158 void
 159 __gmp_mt_recalc_buffer (gmp_uint_least32_t mt[])
 160 {
 161   gmp_uint_least32_t y;
 162   int kk;
 163
 164   for (kk = 0; kk < N - M; kk++)
 165     {
 166       y = (mt[kk] & 0x80000000) | (mt[kk + 1] & 0x7FFFFFFF);
 167       mt[kk] = mt[kk + M] ^ (y >> 1) ^ ((y & 0x01) != 0 ? MATRIX_A : 0);
 168     }
 169   for (; kk < N - 1; kk++)
 170     {
 171       y = (mt[kk] & 0x80000000) | (mt[kk + 1] & 0x7FFFFFFF);
 172       mt[kk] = mt[kk - (N - M)] ^ (y >> 1) ^ ((y & 0x01) != 0 ? MATRIX_A : 0);
 173     }
 174
 175   y = (mt[N - 1] & 0x80000000) | (mt[0] & 0x7FFFFFFF);
 176   mt[N - 1] = mt[M - 1] ^ (y >> 1) ^ ((y & 0x01) != 0 ? MATRIX_A : 0);
 177 }
 178
 179
 180 /* Get nbits bits of output from the generator into dest.
 181    Note that Mersenne Twister is designed to produce outputs in
 182    32-bit words.  */
 183 void
 184 __gmp_randget_mt (gmp_randstate_t rstate, mp_ptr dest, unsigned long int nbits)
 185 {
 186   gmp_uint_least32_t y;
 187   int rbits;
 188   mp_size_t i;
 189   mp_size_t nlimbs;
 190   int *pmti;
 191   gmp_uint_least32_t *mt;
 192
 193   pmti = &((gmp_rand_mt_struct *) RNG_STATE (rstate))->mti;
 194   mt = ((gmp_rand_mt_struct *) RNG_STATE (rstate))->mt;
 195
 196   nlimbs = nbits / GMP_NUMB_BITS;
 197   rbits = nbits % GMP_NUMB_BITS;
 198
 199 #define NEXT_RANDOM                     \
 200   do                                    \
 201     {                                   \
 202       if (*pmti >= N)                   \
 203         {                               \
 204           __gmp_mt_recalc_buffer (mt);  \
 205           *pmti = 0;                    \
 206         }                               \
 207       y = mt[(*pmti)++];                \
 208       y ^= (y >> 11);                   \
 209       y ^= (y << 7) & MASK_1;           \
 210       y ^= (y << 15) & MASK_2;          \
 211       y ^= (y >> 18);                   \
 212     }                                   \
 213   while (0)
 214
 215
 216   /* Handle the common cases of 32- or 64-bit limbs with fast,
 217      optimized routines, and the rest of cases with a general
 218      routine.  In all cases, no more than 31 bits are rejected
 219      for the last limb so that every version of the code is
 220      consistent with the others.  */
 221
 222 #if (GMP_NUMB_BITS == 32)
 223
 224   for (i = 0; i < nlimbs; i++)
 225     {
 226       NEXT_RANDOM;
 227       dest[i] = (mp_limb_t) y;
 228     }
 229   if (rbits)
 230     {
 231       NEXT_RANDOM;
 232       dest[nlimbs] = (mp_limb_t) (y & ~(ULONG_MAX << rbits));
 233     }
 234
 235 #else /* GMP_NUMB_BITS != 32 */
 236 #if (GMP_NUMB_BITS == 64)
 237
 238   for (i = 0; i < nlimbs; i++)
 239     {
 240       NEXT_RANDOM;
 241       dest[i] = (mp_limb_t) y;
 242       NEXT_RANDOM;
 243       dest[i] |= (mp_limb_t) y << 32;
 244     }
 245   if (rbits)
 246     {
 247       if (rbits < 32)
 248         {
 249           NEXT_RANDOM;
 250           dest[nlimbs] = (mp_limb_t) (y & ~(ULONG_MAX << rbits));
 251         }
 252       else
 253         {
 254           NEXT_RANDOM;
 255           dest[nlimbs] = (mp_limb_t) y;
 256           if (rbits > 32)
 257             {
 258               NEXT_RANDOM;
 259               dest[nlimbs] |=
 260                 ((mp_limb_t) (y & ~(ULONG_MAX << (rbits-32)))) << 32;
 261             }
 262         }
 263     }
 264
 265 #else /* GMP_NUMB_BITS != 64 */
 266
 267   {
 268     /* Fall back to a general algorithm.  This algorithm works by
 269        keeping a pool of up to 64 bits (2 outputs from MT) acting
 270        as a shift register from which bits are consumed as needed.
 271        Bits are consumed using the LSB bits of bitpool_l, and
 272        inserted via bitpool_h and shifted to the right place.  */
 273
 274     gmp_uint_least32_t bitpool_h = 0;
 275     gmp_uint_least32_t bitpool_l = 0;
 276     int bits_in_pool = 0;       /* Holds number of valid bits in the pool.  */
 277     int bits_to_fill;           /* Holds total number of bits to put in
 278                                    destination.  */
 279     int bitidx;                 /* Holds the destination bit position.  */
 280     mp_size_t nlimbs2;          /* Number of whole+partial limbs to fill.  */
 281
 282     nlimbs2 = nlimbs + (rbits != 0);
 283
 284     for (i = 0; i < nlimbs2; i++)
 285       {
 286         bitidx = 0;
 287         if (i < nlimbs)
 288           bits_to_fill = GMP_NUMB_BITS;
 289         else
 290           bits_to_fill = rbits;
 291
 292         dest[i] = CNST_LIMB (0);
 293         while (bits_to_fill >= 32) /* Process whole 32-bit blocks first.  */
 294           {
 295             if (bits_in_pool < 32)      /* Need more bits.  */
 296               {
 297                 /* 64-bit right shift.  */
 298                 NEXT_RANDOM;
 299                 bitpool_h = y;
 300                 bitpool_l |= (bitpool_h << bits_in_pool) & 0xFFFFFFFF;
 301                 if (bits_in_pool == 0)
 302                   bitpool_h = 0;
 303                 else
 304                   bitpool_h >>= 32 - bits_in_pool;
 305                 bits_in_pool += 32;     /* We've got 32 more bits.  */
 306               }
 307
 308             /* Fill a 32-bit chunk.  */
 309             dest[i] |= ((mp_limb_t) bitpool_l) << bitidx;
 310             bitpool_l = bitpool_h;
 311             bits_in_pool -= 32;
 312             bits_to_fill -= 32;
 313             bitidx += 32;
 314           }
 315
 316         /* Cover the case where GMP_NUMB_BITS is not a multiple of 32.  */
 317         if (bits_to_fill != 0)
 318           {
 319             if (bits_in_pool < bits_to_fill)
 320               {
 321                 NEXT_RANDOM;
 322                 bitpool_h = y;
 323                 bitpool_l |= (bitpool_h << bits_in_pool) & 0xFFFFFFFF;
 324                 if (bits_in_pool == 0)
 325                   bitpool_h = 0;
 326                 else
 327                   bitpool_h >>= 32 - bits_in_pool;
 328                 bits_in_pool += 32;
 329               }
 330
 331             dest[i] |= (((mp_limb_t) bitpool_l
 332                          & ~(~CNST_LIMB (0) << bits_to_fill))
 333                         << bitidx);
 334             bitpool_l = ((bitpool_l >> bits_to_fill)
 335                          | (bitpool_h << (32 - bits_to_fill))) & 0xFFFFFFFF;
 336             bitpool_h >>= bits_to_fill;
 337             bits_in_pool -= bits_to_fill;
 338           }
 339       }
 340   }
 341
 342 #endif /* GMP_NUMB_BITS != 64 */
 343 #endif /* GMP_NUMB_BITS != 32 */
 344 }
 345
 346 void
 347 __gmp_randclear_mt (gmp_randstate_t rstate)
 348 {
 349   (*__gmp_free_func) ((void *) RNG_STATE (rstate),
 350                       ALLOC (rstate->_mp_seed) * BYTES_PER_MP_LIMB);
 351 }
 352
 353 void __gmp_randiset_mt __GMP_PROTO ((gmp_randstate_ptr dst, gmp_randstate_srcptr src));
 354
 355 static const gmp_randfnptr_t Mersenne_Twister_Generator_Noseed = {
 356   NULL,
 357   __gmp_randget_mt,
 358   __gmp_randclear_mt,
 359   __gmp_randiset_mt
 360 };
 361
 362 void
 363 __gmp_randiset_mt (gmp_randstate_ptr dst, gmp_randstate_srcptr src)
 364 {
 365   const mp_size_t sz = ((sizeof (gmp_rand_mt_struct) - 1) / BYTES_PER_MP_LIMB) + 1;
 366   gmp_rand_mt_struct *dstp, *srcp;
 367   mp_size_t i;
 368
 369   /* Set the generator functions.  */
 370   RNG_FNPTR (dst) = (void *) &Mersenne_Twister_Generator_Noseed;
 371
 372   /* Allocate the MT-specific state.  */
 373   dstp = (gmp_rand_mt_struct *) __GMP_ALLOCATE_FUNC_LIMBS (sz);
 374   RNG_STATE (dst) = (mp_ptr) dstp;
 375   ALLOC (dst->_mp_seed) = sz;     /* Initialize alloc field to placate Camm.  */
 376
 377   /* Copy state.  */
 378   srcp = (gmp_rand_mt_struct *) RNG_STATE (src);
 379   for (i = 0; i < N; i++)
 380     dstp->mt[i] = srcp->mt[i];
 381
 382   dstp->mti = srcp->mti;
 383 }
 384
 385 void
 386 __gmp_randinit_mt_noseed (gmp_randstate_ptr dst)
 387 {
 388   const mp_size_t sz = ((sizeof (gmp_rand_mt_struct) - 1) / BYTES_PER_MP_LIMB) + 1;
 389   gmp_rand_mt_struct *dstp;
 390   mp_size_t i;
 391
 392   /* Set the generator functions.  */
 393   RNG_FNPTR (dst) = (void *) &Mersenne_Twister_Generator_Noseed;
 394
 395   /* Allocate the MT-specific state.  */
 396   dstp = (gmp_rand_mt_struct *) __GMP_ALLOCATE_FUNC_LIMBS (sz);
 397   RNG_STATE (dst) = (mp_ptr) dstp;
 398   ALLOC (dst->_mp_seed) = sz;     /* Initialize alloc field to placate Camm.  */
 399
 400   /* Set state for default seed.  */
 401   for (i = 0; i < N; i++)
 402     dstp->mt[i] = default_state[i];
 403
 404   dstp->mti = WARM_UP % N;
 405 }