Use past SE information also for success cases

[stockfish] / src / mersenne.cpp

diff --git a/src/mersenne.cpp b/src/mersenne.cpp
index 2213e4ac9f3abc65c06e8c5e9fed04b65702db7e..332ad6c6f04b931eb9b74c04ce825f9685b4cbd8 100644 (file)
--- a/src/mersenne.cpp
+++ b/src/mersenne.cpp
@@ -1,12 +1,12 @@
-/* 
+/*

    A C-program for MT19937, with initialization improved 2002/1/26.
    Coded by Takuji Nishimura and Makoto Matsumoto.
 
    A C-program for MT19937, with initialization improved 2002/1/26.
    Coded by Takuji Nishimura and Makoto Matsumoto.
 

-   Before using, initialize the state by using init_genrand(seed)  
+   Before using, initialize the state by using init_genrand(seed)

    or init_by_array(init_key, key_length).
 
    Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
    or init_by_array(init_key, key_length).
 
    Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,

-   All rights reserved.                          
+   All rights reserved.

 
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
 
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions


@@ -19,8 +19,8 @@
         notice, this list of conditions and the following disclaimer in the
         documentation and/or other materials provided with the distribution.
 
         notice, this list of conditions and the following disclaimer in the
         documentation and/or other materials provided with the distribution.
 

-     3. The names of its contributors may not be used to endorse or promote 
-        products derived from this software without specific prior written 
+     3. The names of its contributors may not be used to endorse or promote
+        products derived from this software without specific prior written

         permission.
 
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
         permission.
 
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS


@@ -41,108 +41,131 @@
    email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
 */
 
    email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
 */
 

-#include "types.h"
-
-/* Period parameters */  
-#define N 624
-#define M 397
-#define MATRIX_A 0x9908b0dfUL   /* constant vector a */
-#define UPPER_MASK 0x80000000UL /* most significant w-r bits */
-#define LOWER_MASK 0x7fffffffUL /* least significant r bits */
-
-static unsigned long mt[N]; /* the array for the state vector  */
-static int mti=N+1; /* mti==N+1 means mt[N] is not initialized */
-
-/* initializes mt[N] with a seed */
-void init_genrand(unsigned long s)
-{
-    mt[0]= s & 0xffffffffUL;
-    for (mti=1; mti<N; mti++) {
-        mt[mti] = 
-            (1812433253UL * (mt[mti-1] ^ (mt[mti-1] >> 30)) + mti); 
-        /* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
-        /* In the previous versions, MSBs of the seed affect   */
-        /* only MSBs of the array mt[].                        */
-        /* 2002/01/09 modified by Makoto Matsumoto             */
-        mt[mti] &= 0xffffffffUL;
-        /* for >32 bit machines */
-    }
-}
+#include "mersenne.h"
+
+namespace {
+
+  // Period parameters
+  const int N = 624;
+  const int M = 397;
+  const unsigned long MATRIX_A   = 0x9908b0dfUL; // Constant vector a
+  const unsigned long UPPER_MASK = 0x80000000UL; // Most significant w-r bits
+  const unsigned long LOWER_MASK = 0x7fffffffUL; // Least significant r bits
+
+  unsigned long mt[N]; // The array for the state vector
+  int mti = N + 1;     // mti == N+1 means mt[N] is not initialized
+
+  // Initializes mt[N] with a seed
+  void init_genrand(unsigned long s) {
+
+      mt[0]= s & 0xffffffffUL;
+      for (mti = 1; mti < N; mti++)
+      {
+          // See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier.
+          // In the previous versions, MSBs of the seed affect
+          // only MSBs of the array mt[].
+          // 2002/01/09 modified by Makoto Matsumoto
+          mt[mti] = 1812433253UL * (mt[mti-1] ^ (mt[mti-1] >> 30)) + mti;
+          mt[mti] &= 0xffffffffUL; // For > 32 bit machines
+      }
+  }

 
 

-/* initialize by an array with array-length */
-/* init_key is the array for initializing keys */
-/* key_length is its length */
-/* slight change for C++, 2004/2/26 */
-void init_by_array(unsigned long init_key[], int key_length)
-{
-    int i, j, k;
-    init_genrand(19650218UL);
-    i=1; j=0;
-    k = (N>key_length ? N : key_length);
-    for (; k; k--) {
-        mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1664525UL))
-          + init_key[j] + j; /* non linear */
-        mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
-        i++; j++;
-        if (i>=N) { mt[0] = mt[N-1]; i=1; }
-        if (j>=key_length) j=0;
-    }
-    for (k=N-1; k; k--) {
-        mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1566083941UL))
-          - i; /* non linear */
-        mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
-        i++;
-        if (i>=N) { mt[0] = mt[N-1]; i=1; }
-    }
-
-    mt[0] = 0x80000000UL; /* MSB is 1; assuring non-zero initial array */ 
-}
+  // Initialize by an array with array-length
+  // init_key is the array for initializing keys
+  // key_length is its length
+  // slight change for C++, 2004/2/26
+  void init_by_array(unsigned long init_key[], int key_length) {
+
+      int i = 1;
+      int j = 0;
+      int k = (N > key_length ? N : key_length);
+
+      init_genrand(19650218UL);
+
+      for ( ; k; k--)
+      {
+          mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1664525UL)) + init_key[j] + j; // Non linear
+          mt[i] &= 0xffffffffUL; // For WORDSIZE > 32 machines
+          i++; j++;
+          if (i >= N)
+          {
+              mt[0] = mt[N-1];
+              i = 1;
+          }
+          if (j >= key_length)
+              j = 0;
+      }
+      for (k = N-1; k; k--)
+      {
+          mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1566083941UL)) - i; // Non linear
+          mt[i] &= 0xffffffffUL; // For WORDSIZE > 32 machines
+          i++;
+          if (i >= N)
+          {
+              mt[0] = mt[N-1];
+              i = 1;
+          }
+      }
+      mt[0] = 0x80000000UL; // MSB is 1; assuring non-zero initial array
+  }

 
 

-/* generates a random number on [0,0xffffffff]-interval */
-uint32_t genrand_int32(void) {
-  unsigned long y;
-  static unsigned long mag01[2]={0x0UL, MATRIX_A};
-  /* mag01[x] = x * MATRIX_A  for x=0,1 */
+} // namespace

 
 

-  if (mti >= N) { /* generate N words at one time */
-    int kk;

 
 

-    if (mti == N+1)   /* if init_genrand() has not been called, */
-      init_genrand(5489UL); /* a default initial seed is used */
+// Generates a random number on [0,0xffffffff]-interval
+uint32_t genrand_int32() {

 
 

-    for (kk=0;kk<N-M;kk++) {
-      y = (mt[kk]&UPPER_MASK)|(mt[kk+1]&LOWER_MASK);
-      mt[kk] = mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1UL];
-    }
-    for (;kk<N-1;kk++) {
-      y = (mt[kk]&UPPER_MASK)|(mt[kk+1]&LOWER_MASK);
-      mt[kk] = mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1UL];
-    }
-    y = (mt[N-1]&UPPER_MASK)|(mt[0]&LOWER_MASK);
-    mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1UL];
+  unsigned long y;
+  static unsigned long mag01[2] = {0x0UL, MATRIX_A};
+  /* mag01[x] = x * MATRIX_A  for x=0,1 */

 
 

-    mti = 0;
+  // Generate N words at one time
+  if (mti >= N)
+  {
+      int kk;
+
+      if (mti == N+1)           // If init_genrand() has not been called,
+          init_genrand(5489UL); // a default initial seed is used.
+
+      for (kk = 0; kk < N-M; kk++)
+      {
+          y = (mt[kk] & UPPER_MASK) | (mt[kk+1] & LOWER_MASK);
+          mt[kk] = mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1UL];
+      }
+      for ( ; kk < N-1; kk++)
+      {
+          y = (mt[kk] & UPPER_MASK) | (mt[kk+1] & LOWER_MASK);
+          mt[kk] = mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1UL];
+      }
+      y = (mt[N-1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
+      mt[N-1] = mt[M-1] ^ (y >> 1) ^ mag01[y & 0x1UL];
+      mti = 0;

   }
   }

-  
+

   y = mt[mti++];
 
   y = mt[mti++];
 

-  /* Tempering */
+  // Tempering

   y ^= (y >> 11);
   y ^= (y >> 11);

-  y ^= (y << 7) & 0x9d2c5680UL;
+  y ^= (y <<  7) & 0x9d2c5680UL;

   y ^= (y << 15) & 0xefc60000UL;
   y ^= (y >> 18);
 
   return y;
 }
 
   y ^= (y << 15) & 0xefc60000UL;
   y ^= (y >> 18);
 
   return y;
 }
 

-uint64_t genrand_int64(void) {
+uint64_t genrand_int64() {
+

   uint64_t x, y;
 
   uint64_t x, y;
 

-  x = genrand_int32(); y = genrand_int32();
-  return (x<<32)|y;
+  x = genrand_int32();
+  y = genrand_int32();
+  return (x << 32) | y;

 }
 
 }
 

-void init_mersenne(void) {
-  unsigned long init[4]={0x123, 0x234, 0x345, 0x456}, length=4;
+void init_mersenne() {
+
+  unsigned long init[4] = {0x123, 0x234, 0x345, 0x456};
+  unsigned long length = 4;
+

   init_by_array(init, length);
 }
   init_by_array(init, length);
 }