src/parsec/disk-image/parsec/parsec-benchmark/pkgs/libs/gsl/src/rng/ranlxs.c - public/gem5-resources - Git at Google

 /* rng/ranlxs.c
  *
  * Copyright (C) 1996, 1997, 1998, 1999, 2000 James Theiler, Brian Gough
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or (at
  * your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */

 #include <config.h>
 #include <stdlib.h>
 #include <gsl/gsl_rng.h>

 /* This is an implementation of M. Luescher's second generation
    version of the RANLUX generator.

    Thanks to Martin Luescher for providing information on this
    generator.

  */

 static unsigned long int ranlxs_get (void *vstate);
 static inline double ranlxs_get_double (void *vstate);
 static void ranlxs_set_lux (void *state, unsigned long int s, unsigned int luxury);
 static void ranlxs0_set (void *state, unsigned long int s);
 static void ranlxs1_set (void *state, unsigned long int s);
 static void ranlxs2_set (void *state, unsigned long int s);

 static const int next[12] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 0};
 static const int snext[24] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
                               14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 0};

 static const double sbase = 16777216.0;         /* 2^24 */
 static const double sone_bit = 1.0 / 16777216.0;        /* 1/2^24 */
 static const double one_bit = 1.0 / 281474976710656.0;  /* 1/2^48 */

 static const double shift = 268435456.0;        /* 2^28 */

 #define RANLUX_STEP(x1,x2,i1,i2,i3)      \
           x1=xdbl[i1] - xdbl[i2];        \
           if (x2 < 0)                    \
           {                              \
             x1-=one_bit;                 \
             x2+=1;                       \
           }                              \
           xdbl[i3]=x2

 typedef struct
   {
     double xdbl[12], ydbl[12];  /* doubles first so they are 8-byte aligned */
     double carry;
     float xflt[24];
     unsigned int ir;
     unsigned int jr;
     unsigned int is;
     unsigned int is_old;
     unsigned int pr;
   }
 ranlxs_state_t;

 static void increment_state (ranlxs_state_t * state);

 static void
 increment_state (ranlxs_state_t * state)
 {
   int k, kmax, m;
   double x, y1, y2, y3;

   float *xflt = state->xflt;
   double *xdbl = state->xdbl;
   double *ydbl = state->ydbl;
   double carry = state->carry;
   unsigned int ir = state->ir;
   unsigned int jr = state->jr;

   for (k = 0; ir > 0; ++k)
     {
       y1 = xdbl[jr] - xdbl[ir];
       y2 = y1 - carry;
       if (y2 < 0)
         {
           carry = one_bit;
           y2 += 1;
         }
       else
         {
           carry = 0;
         }
       xdbl[ir] = y2;
       ir = next[ir];
       jr = next[jr];
     }

   kmax = state->pr - 12;

   for (; k <= kmax; k += 12)
     {
       y1 = xdbl[7] - xdbl[0];
       y1 -= carry;

       RANLUX_STEP (y2, y1, 8, 1, 0);
       RANLUX_STEP (y3, y2, 9, 2, 1);
       RANLUX_STEP (y1, y3, 10, 3, 2);
       RANLUX_STEP (y2, y1, 11, 4, 3);
       RANLUX_STEP (y3, y2, 0, 5, 4);
       RANLUX_STEP (y1, y3, 1, 6, 5);
       RANLUX_STEP (y2, y1, 2, 7, 6);
       RANLUX_STEP (y3, y2, 3, 8, 7);
       RANLUX_STEP (y1, y3, 4, 9, 8);
       RANLUX_STEP (y2, y1, 5, 10, 9);
       RANLUX_STEP (y3, y2, 6, 11, 10);

       if (y3 < 0)
         {
           carry = one_bit;
           y3 += 1;
         }
       else
         {
           carry = 0;
         }
       xdbl[11] = y3;
     }

   kmax = state->pr;

   for (; k < kmax; ++k)
     {
       y1 = xdbl[jr] - xdbl[ir];
       y2 = y1 - carry;
       if (y2 < 0)
         {
           carry = one_bit;
           y2 += 1;
         }
       else
         {
           carry = 0;
         }
       xdbl[ir] = y2;
       ydbl[ir] = y2 + shift;
       ir = next[ir];
       jr = next[jr];
     }

   ydbl[ir] = xdbl[ir] + shift;

   for (k = next[ir]; k > 0;)
     {
       ydbl[k] = xdbl[k] + shift;
       k = next[k];
     }

   for (k = 0, m = 0; k < 12; ++k)
     {
       x = xdbl[k];
       y2 = ydbl[k] - shift;
       if (y2 > x)
         y2 -= sone_bit;
       y1 = (x - y2) * sbase;

       xflt[m++] = (float) y1;
       xflt[m++] = (float) y2;
     }

   state->ir = ir;
   state->is = 2 * ir;
   state->is_old = 2 * ir;
   state->jr = jr;
   state->carry = carry;
 }


 static inline double
 ranlxs_get_double (void *vstate)
 {
   ranlxs_state_t *state = (ranlxs_state_t *) vstate;

   const unsigned int is = snext[state->is];

   state->is = is;

   if (is == state->is_old)
     increment_state (state);

   return state->xflt[state->is];
 }

 static unsigned long int
 ranlxs_get (void *vstate)
 {
   return ranlxs_get_double (vstate) * 16777216.0;       /* 2^24 */
 }

 static void
 ranlxs_set_lux (void *vstate, unsigned long int s, unsigned int luxury)
 {
   ranlxs_state_t *state = (ranlxs_state_t *) vstate;

   int ibit, jbit, i, k, m, xbit[31];
   double x, y;

   long int seed;

   if (s == 0)
     s = 1;                      /* default seed is 1 */

   seed = s;

   i = seed & 0xFFFFFFFFUL;

   for (k = 0; k < 31; ++k)
     {
       xbit[k] = i % 2;
       i /= 2;
     }

   ibit = 0;
   jbit = 18;

   for (k = 0; k < 12; ++k)
     {
       x = 0;

       for (m = 1; m <= 48; ++m)
         {
           y = (double) xbit[ibit];
           x += x + y;
           xbit[ibit] = (xbit[ibit] + xbit[jbit]) % 2;
           ibit = (ibit + 1) % 31;
           jbit = (jbit + 1) % 31;
         }
       state->xdbl[k] = one_bit * x;
     }

   state->carry = 0;
   state->ir = 0;
   state->jr = 7;
   state->is = 23;
   state->is_old = 0;
   state->pr = luxury;
 }

 static void
 ranlxs0_set (void *vstate, unsigned long int s)
 {
   ranlxs_set_lux (vstate, s, 109);
 }

 void
 ranlxs1_set (void *vstate, unsigned long int s)
 {
   ranlxs_set_lux (vstate, s, 202);
 }

 static void
 ranlxs2_set (void *vstate, unsigned long int s)
 {
   ranlxs_set_lux (vstate, s, 397);
 }


 static const gsl_rng_type ranlxs0_type =
 {"ranlxs0",                     /* name */
  0x00ffffffUL,                  /* RAND_MAX */
  0,                             /* RAND_MIN */
  sizeof (ranlxs_state_t),
  &ranlxs0_set,
  &ranlxs_get,
  &ranlxs_get_double};

 static const gsl_rng_type ranlxs1_type =
 {"ranlxs1",                     /* name */
  0x00ffffffUL,                  /* RAND_MAX */
  0,                             /* RAND_MIN */
  sizeof (ranlxs_state_t),
  &ranlxs1_set,
  &ranlxs_get,
  &ranlxs_get_double};

 static const gsl_rng_type ranlxs2_type =
 {"ranlxs2",                     /* name */
  0x00ffffffUL,                  /* RAND_MAX */
  0,                             /* RAND_MIN */
  sizeof (ranlxs_state_t),
  &ranlxs2_set,
  &ranlxs_get,
  &ranlxs_get_double};

 const gsl_rng_type *gsl_rng_ranlxs0 = &ranlxs0_type;
 const gsl_rng_type *gsl_rng_ranlxs1 = &ranlxs1_type;
 const gsl_rng_type *gsl_rng_ranlxs2 = &ranlxs2_type;
	/* rng/ranlxs.c
	*
	* Copyright (C) 1996, 1997, 1998, 1999, 2000 James Theiler, Brian Gough
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or (at
	* your option) any later version.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	*/

	#include <config.h>
	#include <stdlib.h>
	#include <gsl/gsl_rng.h>

	/* This is an implementation of M. Luescher's second generation
	version of the RANLUX generator.

	Thanks to Martin Luescher for providing information on this
	generator.

	*/

	static unsigned long int ranlxs_get (void *vstate);
	static inline double ranlxs_get_double (void *vstate);
	static void ranlxs_set_lux (void *state, unsigned long int s, unsigned int luxury);
	static void ranlxs0_set (void *state, unsigned long int s);
	static void ranlxs1_set (void *state, unsigned long int s);
	static void ranlxs2_set (void *state, unsigned long int s);

	static const int next[12] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 0};
	static const int snext[24] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
	14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 0};

	static const double sbase = 16777216.0; /* 2^24 */
	static const double sone_bit = 1.0 / 16777216.0; /* 1/2^24 */
	static const double one_bit = 1.0 / 281474976710656.0; /* 1/2^48 */

	static const double shift = 268435456.0; /* 2^28 */

	#define RANLUX_STEP(x1,x2,i1,i2,i3) \
	x1=xdbl[i1] - xdbl[i2]; \
	if (x2 < 0) \
	{ \
	x1-=one_bit; \
	x2+=1; \
	} \
	xdbl[i3]=x2

	typedef struct
	{
	double xdbl[12], ydbl[12]; /* doubles first so they are 8-byte aligned */
	double carry;
	float xflt[24];
	unsigned int ir;
	unsigned int jr;
	unsigned int is;
	unsigned int is_old;
	unsigned int pr;
	}
	ranlxs_state_t;

	static void increment_state (ranlxs_state_t * state);

	static void
	increment_state (ranlxs_state_t * state)
	{
	int k, kmax, m;
	double x, y1, y2, y3;

	float *xflt = state->xflt;
	double *xdbl = state->xdbl;
	double *ydbl = state->ydbl;
	double carry = state->carry;
	unsigned int ir = state->ir;
	unsigned int jr = state->jr;

	for (k = 0; ir > 0; ++k)
	{
	y1 = xdbl[jr] - xdbl[ir];
	y2 = y1 - carry;
	if (y2 < 0)
	{
	carry = one_bit;
	y2 += 1;
	}
	else
	{
	carry = 0;
	}
	xdbl[ir] = y2;
	ir = next[ir];
	jr = next[jr];
	}

	kmax = state->pr - 12;

	for (; k <= kmax; k += 12)
	{
	y1 = xdbl[7] - xdbl[0];
	y1 -= carry;

	RANLUX_STEP (y2, y1, 8, 1, 0);
	RANLUX_STEP (y3, y2, 9, 2, 1);
	RANLUX_STEP (y1, y3, 10, 3, 2);
	RANLUX_STEP (y2, y1, 11, 4, 3);
	RANLUX_STEP (y3, y2, 0, 5, 4);
	RANLUX_STEP (y1, y3, 1, 6, 5);
	RANLUX_STEP (y2, y1, 2, 7, 6);
	RANLUX_STEP (y3, y2, 3, 8, 7);
	RANLUX_STEP (y1, y3, 4, 9, 8);
	RANLUX_STEP (y2, y1, 5, 10, 9);
	RANLUX_STEP (y3, y2, 6, 11, 10);

	if (y3 < 0)
	{
	carry = one_bit;
	y3 += 1;
	}
	else
	{
	carry = 0;
	}
	xdbl[11] = y3;
	}

	kmax = state->pr;

	for (; k < kmax; ++k)
	{
	y1 = xdbl[jr] - xdbl[ir];
	y2 = y1 - carry;
	if (y2 < 0)
	{
	carry = one_bit;
	y2 += 1;
	}
	else
	{
	carry = 0;
	}
	xdbl[ir] = y2;
	ydbl[ir] = y2 + shift;
	ir = next[ir];
	jr = next[jr];
	}

	ydbl[ir] = xdbl[ir] + shift;

	for (k = next[ir]; k > 0;)
	{
	ydbl[k] = xdbl[k] + shift;
	k = next[k];
	}

	for (k = 0, m = 0; k < 12; ++k)
	{
	x = xdbl[k];
	y2 = ydbl[k] - shift;
	if (y2 > x)
	y2 -= sone_bit;
	y1 = (x - y2) * sbase;

	xflt[m++] = (float) y1;
	xflt[m++] = (float) y2;
	}

	state->ir = ir;
	state->is = 2 * ir;
	state->is_old = 2 * ir;
	state->jr = jr;
	state->carry = carry;
	}


	static inline double
	ranlxs_get_double (void *vstate)
	{
	ranlxs_state_t state = (ranlxs_state_t ) vstate;

	const unsigned int is = snext[state->is];

	state->is = is;

	if (is == state->is_old)
	increment_state (state);

	return state->xflt[state->is];
	}

	static unsigned long int
	ranlxs_get (void *vstate)
	{
	return ranlxs_get_double (vstate) * 16777216.0; /* 2^24 */
	}

	static void
	ranlxs_set_lux (void *vstate, unsigned long int s, unsigned int luxury)
	{
	ranlxs_state_t state = (ranlxs_state_t ) vstate;

	int ibit, jbit, i, k, m, xbit[31];
	double x, y;

	long int seed;

	if (s == 0)
	s = 1; /* default seed is 1 */

	seed = s;

	i = seed & 0xFFFFFFFFUL;

	for (k = 0; k < 31; ++k)
	{
	xbit[k] = i % 2;
	i /= 2;
	}

	ibit = 0;
	jbit = 18;

	for (k = 0; k < 12; ++k)
	{
	x = 0;

	for (m = 1; m <= 48; ++m)
	{
	y = (double) xbit[ibit];
	x += x + y;
	xbit[ibit] = (xbit[ibit] + xbit[jbit]) % 2;
	ibit = (ibit + 1) % 31;
	jbit = (jbit + 1) % 31;
	}
	state->xdbl[k] = one_bit * x;
	}

	state->carry = 0;
	state->ir = 0;
	state->jr = 7;
	state->is = 23;
	state->is_old = 0;
	state->pr = luxury;
	}

	static void
	ranlxs0_set (void *vstate, unsigned long int s)
	{
	ranlxs_set_lux (vstate, s, 109);
	}

	void
	ranlxs1_set (void *vstate, unsigned long int s)
	{
	ranlxs_set_lux (vstate, s, 202);
	}

	static void
	ranlxs2_set (void *vstate, unsigned long int s)
	{
	ranlxs_set_lux (vstate, s, 397);
	}


	static const gsl_rng_type ranlxs0_type =
	{"ranlxs0", /* name */
	0x00ffffffUL, /* RAND_MAX */
	0, /* RAND_MIN */
	sizeof (ranlxs_state_t),
	&ranlxs0_set,
	&ranlxs_get,
	&ranlxs_get_double};

	static const gsl_rng_type ranlxs1_type =
	{"ranlxs1", /* name */
	0x00ffffffUL, /* RAND_MAX */
	0, /* RAND_MIN */
	sizeof (ranlxs_state_t),
	&ranlxs1_set,
	&ranlxs_get,
	&ranlxs_get_double};

	static const gsl_rng_type ranlxs2_type =
	{"ranlxs2", /* name */
	0x00ffffffUL, /* RAND_MAX */
	0, /* RAND_MIN */
	sizeof (ranlxs_state_t),
	&ranlxs2_set,
	&ranlxs_get,
	&ranlxs_get_double};

	const gsl_rng_type *gsl_rng_ranlxs0 = &ranlxs0_type;
	const gsl_rng_type *gsl_rng_ranlxs1 = &ranlxs1_type;
	const gsl_rng_type *gsl_rng_ranlxs2 = &ranlxs2_type;