Retro68/gcc/libgfortran/intrinsics/random.c
2017-10-07 02:16:47 +02:00

951 lines
24 KiB
C

/* Implementation of the RANDOM intrinsics
Copyright (C) 2002-2017 Free Software Foundation, Inc.
Contributed by Lars Segerlund <seger@linuxmail.org>,
Steve Kargl and Janne Blomqvist.
This file is part of the GNU Fortran runtime library (libgfortran).
Libgfortran 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 3 of the License, or (at your option) any later version.
Ligbfortran 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* For rand_s. */
#define _CRT_RAND_S
#include "libgfortran.h"
#include <gthr.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/stat.h>
#include <fcntl.h>
#include "time_1.h"
#ifdef __MINGW32__
#define HAVE_GETPID 1
#include <process.h>
#include <_mingw.h> /* For __MINGW64_VERSION_MAJOR */
#endif
extern void random_r4 (GFC_REAL_4 *);
iexport_proto(random_r4);
extern void random_r8 (GFC_REAL_8 *);
iexport_proto(random_r8);
extern void arandom_r4 (gfc_array_r4 *);
export_proto(arandom_r4);
extern void arandom_r8 (gfc_array_r8 *);
export_proto(arandom_r8);
#ifdef HAVE_GFC_REAL_10
extern void random_r10 (GFC_REAL_10 *);
iexport_proto(random_r10);
extern void arandom_r10 (gfc_array_r10 *);
export_proto(arandom_r10);
#endif
#ifdef HAVE_GFC_REAL_16
extern void random_r16 (GFC_REAL_16 *);
iexport_proto(random_r16);
extern void arandom_r16 (gfc_array_r16 *);
export_proto(arandom_r16);
#endif
#ifdef __GTHREAD_MUTEX_INIT
static __gthread_mutex_t random_lock = __GTHREAD_MUTEX_INIT;
#else
static __gthread_mutex_t random_lock;
#endif
/* Helper routines to map a GFC_UINTEGER_* to the corresponding
GFC_REAL_* types in the range of [0,1). If GFC_REAL_*_RADIX are 2
or 16, respectively, we mask off the bits that don't fit into the
correct GFC_REAL_*, convert to the real type, then multiply by the
correct offset. */
static void
rnumber_4 (GFC_REAL_4 *f, GFC_UINTEGER_4 v)
{
GFC_UINTEGER_4 mask;
#if GFC_REAL_4_RADIX == 2
mask = ~ (GFC_UINTEGER_4) 0u << (32 - GFC_REAL_4_DIGITS);
#elif GFC_REAL_4_RADIX == 16
mask = ~ (GFC_UINTEGER_4) 0u << ((8 - GFC_REAL_4_DIGITS) * 4);
#else
#error "GFC_REAL_4_RADIX has unknown value"
#endif
v = v & mask;
*f = (GFC_REAL_4) v * GFC_REAL_4_LITERAL(0x1.p-32);
}
static void
rnumber_8 (GFC_REAL_8 *f, GFC_UINTEGER_8 v)
{
GFC_UINTEGER_8 mask;
#if GFC_REAL_8_RADIX == 2
mask = ~ (GFC_UINTEGER_8) 0u << (64 - GFC_REAL_8_DIGITS);
#elif GFC_REAL_8_RADIX == 16
mask = ~ (GFC_UINTEGER_8) 0u << (16 - GFC_REAL_8_DIGITS) * 4);
#else
#error "GFC_REAL_8_RADIX has unknown value"
#endif
v = v & mask;
*f = (GFC_REAL_8) v * GFC_REAL_8_LITERAL(0x1.p-64);
}
#ifdef HAVE_GFC_REAL_10
static void
rnumber_10 (GFC_REAL_10 *f, GFC_UINTEGER_8 v)
{
GFC_UINTEGER_8 mask;
#if GFC_REAL_10_RADIX == 2
mask = ~ (GFC_UINTEGER_8) 0u << (64 - GFC_REAL_10_DIGITS);
#elif GFC_REAL_10_RADIX == 16
mask = ~ (GFC_UINTEGER_10) 0u << ((16 - GFC_REAL_10_DIGITS) * 4);
#else
#error "GFC_REAL_10_RADIX has unknown value"
#endif
v = v & mask;
*f = (GFC_REAL_10) v * GFC_REAL_10_LITERAL(0x1.p-64);
}
#endif
#ifdef HAVE_GFC_REAL_16
/* For REAL(KIND=16), we only need to mask off the lower bits. */
static void
rnumber_16 (GFC_REAL_16 *f, GFC_UINTEGER_8 v1, GFC_UINTEGER_8 v2)
{
GFC_UINTEGER_8 mask;
#if GFC_REAL_16_RADIX == 2
mask = ~ (GFC_UINTEGER_8) 0u << (128 - GFC_REAL_16_DIGITS);
#elif GFC_REAL_16_RADIX == 16
mask = ~ (GFC_UINTEGER_8) 0u << ((32 - GFC_REAL_16_DIGITS) * 4);
#else
#error "GFC_REAL_16_RADIX has unknown value"
#endif
v2 = v2 & mask;
*f = (GFC_REAL_16) v1 * GFC_REAL_16_LITERAL(0x1.p-64)
+ (GFC_REAL_16) v2 * GFC_REAL_16_LITERAL(0x1.p-128);
}
#endif
/*
We use the xorshift1024* generator, a fast high-quality generator
that:
- passes TestU1 without any failures
- provides a "jump" function making it easy to provide many
independent parallel streams.
- Long period of 2**1024 - 1
A description can be found at
http://vigna.di.unimi.it/ftp/papers/xorshift.pdf
or
http://arxiv.org/abs/1402.6246
The paper includes public domain source code which is the basis for
the implementation below.
*/
typedef struct
{
bool init;
int p;
uint64_t s[16];
}
xorshift1024star_state;
/* master_init, njumps, and master_state are the only variables
protected by random_lock. */
static bool master_init;
static unsigned njumps; /* How many times we have jumped. */
static uint64_t master_state[] = {
0xad63fa1ed3b55f36ULL, 0xd94473e78978b497ULL, 0xbc60592a98172477ULL,
0xa3de7c6e81265301ULL, 0x586640c5e785af27ULL, 0x7a2a3f63b67ce5eaULL,
0x9fde969f922d9b82ULL, 0xe6fe34379b3f3822ULL, 0x6c277eac3e99b6c2ULL,
0x9197290ab0d3f069ULL, 0xdb227302f6c25576ULL, 0xee0209aee527fae9ULL,
0x675666a793cd05b9ULL, 0xd048c99fbc70c20fULL, 0x775f8c3dba385ef5ULL,
0x625288bc262faf33ULL
};
static __gthread_key_t rand_state_key;
static xorshift1024star_state*
get_rand_state (void)
{
/* For single threaded apps. */
static xorshift1024star_state rand_state;
if (__gthread_active_p ())
{
void* p = __gthread_getspecific (rand_state_key);
if (!p)
{
p = xcalloc (1, sizeof (xorshift1024star_state));
__gthread_setspecific (rand_state_key, p);
}
return p;
}
else
return &rand_state;
}
static uint64_t
xorshift1024star (xorshift1024star_state* rs)
{
int p = rs->p;
const uint64_t s0 = rs->s[p];
uint64_t s1 = rs->s[p = (p + 1) & 15];
s1 ^= s1 << 31;
rs->s[p] = s1 ^ s0 ^ (s1 >> 11) ^ (s0 >> 30);
rs->p = p;
return rs->s[p] * UINT64_C(1181783497276652981);
}
/* This is the jump function for the generator. It is equivalent to
2^512 calls to xorshift1024star(); it can be used to generate 2^512
non-overlapping subsequences for parallel computations. */
static void
jump (xorshift1024star_state* rs)
{
static const uint64_t JUMP[] = {
0x84242f96eca9c41dULL, 0xa3c65b8776f96855ULL, 0x5b34a39f070b5837ULL,
0x4489affce4f31a1eULL, 0x2ffeeb0a48316f40ULL, 0xdc2d9891fe68c022ULL,
0x3659132bb12fea70ULL, 0xaac17d8efa43cab8ULL, 0xc4cb815590989b13ULL,
0x5ee975283d71c93bULL, 0x691548c86c1bd540ULL, 0x7910c41d10a1e6a5ULL,
0x0b5fc64563b3e2a8ULL, 0x047f7684e9fc949dULL, 0xb99181f2d8f685caULL,
0x284600e3f30e38c3ULL
};
uint64_t t[16] = { 0 };
for(unsigned int i = 0; i < sizeof JUMP / sizeof *JUMP; i++)
for(int b = 0; b < 64; b++)
{
if (JUMP[i] & 1ULL << b)
for(int j = 0; j < 16; j++)
t[j] ^= rs->s[(j + rs->p) & 15];
xorshift1024star (rs);
}
for(int j = 0; j < 16; j++)
rs->s[(j + rs->p) & 15] = t[j];
}
/* Super-simple LCG generator used in getosrandom () if /dev/urandom
doesn't exist. */
#define M 2147483647 /* 2^31 - 1 (A large prime number) */
#define A 16807 /* Prime root of M, passes statistical tests and produces a full cycle */
#define Q 127773 /* M / A (To avoid overflow on A * seed) */
#define R 2836 /* M % A (To avoid overflow on A * seed) */
__attribute__((unused)) static uint32_t
lcg_parkmiller(uint32_t seed)
{
uint32_t hi = seed / Q;
uint32_t lo = seed % Q;
int32_t test = A * lo - R * hi;
if (test <= 0)
test += M;
return test;
}
#undef M
#undef A
#undef Q
#undef R
/* Get some random bytes from the operating system in order to seed
the PRNG. */
static int
getosrandom (void *buf, size_t buflen)
{
/* rand_s is available in MinGW-w64 but not plain MinGW. */
#if defined(__MINGW64_VERSION_MAJOR)
unsigned int* b = buf;
for (unsigned i = 0; i < buflen / sizeof (unsigned int); i++)
rand_s (&b[i]);
return buflen;
#else
/*
TODO: When glibc adds a wrapper for the getrandom() system call
on Linux, one could use that.
TODO: One could use getentropy() on OpenBSD. */
int flags = O_RDONLY;
#ifdef O_CLOEXEC
flags |= O_CLOEXEC;
#endif
int fd = open("/dev/urandom", flags);
if (fd != -1)
{
int res = read(fd, buf, buflen);
close (fd);
return res;
}
uint32_t seed = 1234567890;
time_t secs;
long usecs;
if (gf_gettime (&secs, &usecs) == 0)
{
seed ^= secs;
seed ^= usecs;
}
#ifdef HAVE_GETPID
pid_t pid = getpid();
seed ^= pid;
#endif
uint32_t* ub = buf;
for (size_t i = 0; i < buflen / sizeof (uint32_t); i++)
{
ub[i] = seed;
seed = lcg_parkmiller (seed);
}
return buflen;
#endif /* __MINGW64_VERSION_MAJOR */
}
/* Initialize the random number generator for the current thread,
using the master state and the number of times we must jump. */
static void
init_rand_state (xorshift1024star_state* rs, const bool locked)
{
if (!locked)
__gthread_mutex_lock (&random_lock);
if (!master_init)
{
getosrandom (master_state, sizeof (master_state));
njumps = 0;
master_init = true;
}
memcpy (&rs->s, master_state, sizeof (master_state));
unsigned n = njumps++;
if (!locked)
__gthread_mutex_unlock (&random_lock);
for (unsigned i = 0; i < n; i++)
jump (rs);
rs->init = true;
}
/* This function produces a REAL(4) value from the uniform distribution
with range [0,1). */
void
random_r4 (GFC_REAL_4 *x)
{
xorshift1024star_state* rs = get_rand_state();
if (unlikely (!rs->init))
init_rand_state (rs, false);
uint64_t r = xorshift1024star (rs);
/* Take the higher bits, ensuring that a stream of real(4), real(8),
and real(10) will be identical (except for precision). */
uint32_t high = (uint32_t) (r >> 32);
rnumber_4 (x, high);
}
iexport(random_r4);
/* This function produces a REAL(8) value from the uniform distribution
with range [0,1). */
void
random_r8 (GFC_REAL_8 *x)
{
GFC_UINTEGER_8 r;
xorshift1024star_state* rs = get_rand_state();
if (unlikely (!rs->init))
init_rand_state (rs, false);
r = xorshift1024star (rs);
rnumber_8 (x, r);
}
iexport(random_r8);
#ifdef HAVE_GFC_REAL_10
/* This function produces a REAL(10) value from the uniform distribution
with range [0,1). */
void
random_r10 (GFC_REAL_10 *x)
{
GFC_UINTEGER_8 r;
xorshift1024star_state* rs = get_rand_state();
if (unlikely (!rs->init))
init_rand_state (rs, false);
r = xorshift1024star (rs);
rnumber_10 (x, r);
}
iexport(random_r10);
#endif
/* This function produces a REAL(16) value from the uniform distribution
with range [0,1). */
#ifdef HAVE_GFC_REAL_16
void
random_r16 (GFC_REAL_16 *x)
{
GFC_UINTEGER_8 r1, r2;
xorshift1024star_state* rs = get_rand_state();
if (unlikely (!rs->init))
init_rand_state (rs, false);
r1 = xorshift1024star (rs);
r2 = xorshift1024star (rs);
rnumber_16 (x, r1, r2);
}
iexport(random_r16);
#endif
/* This function fills a REAL(4) array with values from the uniform
distribution with range [0,1). */
void
arandom_r4 (gfc_array_r4 *x)
{
index_type count[GFC_MAX_DIMENSIONS];
index_type extent[GFC_MAX_DIMENSIONS];
index_type stride[GFC_MAX_DIMENSIONS];
index_type stride0;
index_type dim;
GFC_REAL_4 *dest;
xorshift1024star_state* rs = get_rand_state();
int n;
dest = x->base_addr;
dim = GFC_DESCRIPTOR_RANK (x);
for (n = 0; n < dim; n++)
{
count[n] = 0;
stride[n] = GFC_DESCRIPTOR_STRIDE(x,n);
extent[n] = GFC_DESCRIPTOR_EXTENT(x,n);
if (extent[n] <= 0)
return;
}
stride0 = stride[0];
if (unlikely (!rs->init))
init_rand_state (rs, false);
while (dest)
{
/* random_r4 (dest); */
uint64_t r = xorshift1024star (rs);
uint32_t high = (uint32_t) (r >> 32);
rnumber_4 (dest, high);
/* Advance to the next element. */
dest += stride0;
count[0]++;
/* Advance to the next source element. */
n = 0;
while (count[n] == extent[n])
{
/* When we get to the end of a dimension, reset it and increment
the next dimension. */
count[n] = 0;
/* We could precalculate these products, but this is a less
frequently used path so probably not worth it. */
dest -= stride[n] * extent[n];
n++;
if (n == dim)
{
dest = NULL;
break;
}
else
{
count[n]++;
dest += stride[n];
}
}
}
}
/* This function fills a REAL(8) array with values from the uniform
distribution with range [0,1). */
void
arandom_r8 (gfc_array_r8 *x)
{
index_type count[GFC_MAX_DIMENSIONS];
index_type extent[GFC_MAX_DIMENSIONS];
index_type stride[GFC_MAX_DIMENSIONS];
index_type stride0;
index_type dim;
GFC_REAL_8 *dest;
xorshift1024star_state* rs = get_rand_state();
int n;
dest = x->base_addr;
dim = GFC_DESCRIPTOR_RANK (x);
for (n = 0; n < dim; n++)
{
count[n] = 0;
stride[n] = GFC_DESCRIPTOR_STRIDE(x,n);
extent[n] = GFC_DESCRIPTOR_EXTENT(x,n);
if (extent[n] <= 0)
return;
}
stride0 = stride[0];
if (unlikely (!rs->init))
init_rand_state (rs, false);
while (dest)
{
/* random_r8 (dest); */
uint64_t r = xorshift1024star (rs);
rnumber_8 (dest, r);
/* Advance to the next element. */
dest += stride0;
count[0]++;
/* Advance to the next source element. */
n = 0;
while (count[n] == extent[n])
{
/* When we get to the end of a dimension, reset it and increment
the next dimension. */
count[n] = 0;
/* We could precalculate these products, but this is a less
frequently used path so probably not worth it. */
dest -= stride[n] * extent[n];
n++;
if (n == dim)
{
dest = NULL;
break;
}
else
{
count[n]++;
dest += stride[n];
}
}
}
}
#ifdef HAVE_GFC_REAL_10
/* This function fills a REAL(10) array with values from the uniform
distribution with range [0,1). */
void
arandom_r10 (gfc_array_r10 *x)
{
index_type count[GFC_MAX_DIMENSIONS];
index_type extent[GFC_MAX_DIMENSIONS];
index_type stride[GFC_MAX_DIMENSIONS];
index_type stride0;
index_type dim;
GFC_REAL_10 *dest;
xorshift1024star_state* rs = get_rand_state();
int n;
dest = x->base_addr;
dim = GFC_DESCRIPTOR_RANK (x);
for (n = 0; n < dim; n++)
{
count[n] = 0;
stride[n] = GFC_DESCRIPTOR_STRIDE(x,n);
extent[n] = GFC_DESCRIPTOR_EXTENT(x,n);
if (extent[n] <= 0)
return;
}
stride0 = stride[0];
if (unlikely (!rs->init))
init_rand_state (rs, false);
while (dest)
{
/* random_r10 (dest); */
uint64_t r = xorshift1024star (rs);
rnumber_10 (dest, r);
/* Advance to the next element. */
dest += stride0;
count[0]++;
/* Advance to the next source element. */
n = 0;
while (count[n] == extent[n])
{
/* When we get to the end of a dimension, reset it and increment
the next dimension. */
count[n] = 0;
/* We could precalculate these products, but this is a less
frequently used path so probably not worth it. */
dest -= stride[n] * extent[n];
n++;
if (n == dim)
{
dest = NULL;
break;
}
else
{
count[n]++;
dest += stride[n];
}
}
}
}
#endif
#ifdef HAVE_GFC_REAL_16
/* This function fills a REAL(16) array with values from the uniform
distribution with range [0,1). */
void
arandom_r16 (gfc_array_r16 *x)
{
index_type count[GFC_MAX_DIMENSIONS];
index_type extent[GFC_MAX_DIMENSIONS];
index_type stride[GFC_MAX_DIMENSIONS];
index_type stride0;
index_type dim;
GFC_REAL_16 *dest;
xorshift1024star_state* rs = get_rand_state();
int n;
dest = x->base_addr;
dim = GFC_DESCRIPTOR_RANK (x);
for (n = 0; n < dim; n++)
{
count[n] = 0;
stride[n] = GFC_DESCRIPTOR_STRIDE(x,n);
extent[n] = GFC_DESCRIPTOR_EXTENT(x,n);
if (extent[n] <= 0)
return;
}
stride0 = stride[0];
if (unlikely (!rs->init))
init_rand_state (rs, false);
while (dest)
{
/* random_r16 (dest); */
uint64_t r1 = xorshift1024star (rs);
uint64_t r2 = xorshift1024star (rs);
rnumber_16 (dest, r1, r2);
/* Advance to the next element. */
dest += stride0;
count[0]++;
/* Advance to the next source element. */
n = 0;
while (count[n] == extent[n])
{
/* When we get to the end of a dimension, reset it and increment
the next dimension. */
count[n] = 0;
/* We could precalculate these products, but this is a less
frequently used path so probably not worth it. */
dest -= stride[n] * extent[n];
n++;
if (n == dim)
{
dest = NULL;
break;
}
else
{
count[n]++;
dest += stride[n];
}
}
}
}
#endif
/* Number of elements in master_state array. */
#define SZU64 (sizeof (master_state) / sizeof (uint64_t))
/* Keys for scrambling the seed in order to avoid poor seeds. */
static const uint64_t xor_keys[] = {
0xbd0c5b6e50c2df49ULL, 0xd46061cd46e1df38ULL, 0xbb4f4d4ed6103544ULL,
0x114a583d0756ad39ULL, 0x4b5ad8623d0aaab6ULL, 0x3f2ed7afbe0c0f21ULL,
0xdec83fd65f113445ULL, 0x3824f8fbc4f10d24ULL, 0x5d9025af05878911ULL,
0x500bc46b540340e9ULL, 0x8bd53298e0d00530ULL, 0x57886e40a952e06aULL,
0x926e76c88e31cdb6ULL, 0xbd0724dac0a3a5f9ULL, 0xc5c8981b858ab796ULL,
0xbb12ab2694c2b32cULL
};
/* Since a XOR cipher is symmetric, we need only one routine, and we
can use it both for encryption and decryption. */
static void
scramble_seed (uint64_t *dest, const uint64_t *src)
{
for (int i = 0; i < (int) SZU64; i++)
dest[i] = src[i] ^ xor_keys[i];
}
/* random_seed is used to seed the PRNG with either a default
set of seeds or user specified set of seeds. random_seed
must be called with no argument or exactly one argument. */
void
random_seed_i4 (GFC_INTEGER_4 *size, gfc_array_i4 *put, gfc_array_i4 *get)
{
uint64_t seed[SZU64];
#define SZ (sizeof (master_state) / sizeof (GFC_INTEGER_4))
/* Check that we only have one argument present. */
if ((size ? 1 : 0) + (put ? 1 : 0) + (get ? 1 : 0) > 1)
runtime_error ("RANDOM_SEED should have at most one argument present.");
if (size != NULL)
*size = SZ + 1;
xorshift1024star_state* rs = get_rand_state();
/* Return the seed to GET data. */
if (get != NULL)
{
/* If the rank of the array is not 1, abort. */
if (GFC_DESCRIPTOR_RANK (get) != 1)
runtime_error ("Array rank of GET is not 1.");
/* If the array is too small, abort. */
if (GFC_DESCRIPTOR_EXTENT(get,0) < (index_type) SZ + 1)
runtime_error ("Array size of GET is too small.");
if (!rs->init)
init_rand_state (rs, false);
/* Unscramble the seed. */
scramble_seed (seed, rs->s);
/* Then copy it back to the user variable. */
for (size_t i = 0; i < SZ ; i++)
memcpy (&(get->base_addr[(SZ - 1 - i) * GFC_DESCRIPTOR_STRIDE(get,0)]),
(unsigned char*) seed + i * sizeof(GFC_UINTEGER_4),
sizeof(GFC_UINTEGER_4));
/* Finally copy the value of p after the seed. */
get->base_addr[SZ * GFC_DESCRIPTOR_STRIDE(get, 0)] = rs->p;
}
else
{
__gthread_mutex_lock (&random_lock);
/* From the standard: "If no argument is present, the processor assigns
a processor-dependent value to the seed." */
if (size == NULL && put == NULL && get == NULL)
{
master_init = false;
init_rand_state (rs, true);
}
if (put != NULL)
{
/* If the rank of the array is not 1, abort. */
if (GFC_DESCRIPTOR_RANK (put) != 1)
runtime_error ("Array rank of PUT is not 1.");
/* If the array is too small, abort. */
if (GFC_DESCRIPTOR_EXTENT(put,0) < (index_type) SZ + 1)
runtime_error ("Array size of PUT is too small.");
/* We copy the seed given by the user. */
for (size_t i = 0; i < SZ; i++)
memcpy ((unsigned char*) seed + i * sizeof(GFC_UINTEGER_4),
&(put->base_addr[(SZ - 1 - i) * GFC_DESCRIPTOR_STRIDE(put,0)]),
sizeof(GFC_UINTEGER_4));
/* We put it after scrambling the bytes, to paper around users who
provide seeds with quality only in the lower or upper part. */
scramble_seed (master_state, seed);
njumps = 0;
master_init = true;
init_rand_state (rs, true);
rs->p = put->base_addr[SZ * GFC_DESCRIPTOR_STRIDE(put, 0)] & 15;
}
__gthread_mutex_unlock (&random_lock);
}
#undef SZ
}
iexport(random_seed_i4);
void
random_seed_i8 (GFC_INTEGER_8 *size, gfc_array_i8 *put, gfc_array_i8 *get)
{
uint64_t seed[SZU64];
/* Check that we only have one argument present. */
if ((size ? 1 : 0) + (put ? 1 : 0) + (get ? 1 : 0) > 1)
runtime_error ("RANDOM_SEED should have at most one argument present.");
#define SZ (sizeof (master_state) / sizeof (GFC_INTEGER_8))
if (size != NULL)
*size = SZ + 1;
xorshift1024star_state* rs = get_rand_state();
/* Return the seed to GET data. */
if (get != NULL)
{
/* If the rank of the array is not 1, abort. */
if (GFC_DESCRIPTOR_RANK (get) != 1)
runtime_error ("Array rank of GET is not 1.");
/* If the array is too small, abort. */
if (GFC_DESCRIPTOR_EXTENT(get,0) < (index_type) SZ + 1)
runtime_error ("Array size of GET is too small.");
if (!rs->init)
init_rand_state (rs, false);
/* Unscramble the seed. */
scramble_seed (seed, rs->s);
/* This code now should do correct strides. */
for (size_t i = 0; i < SZ; i++)
memcpy (&(get->base_addr[i * GFC_DESCRIPTOR_STRIDE(get,0)]), &seed[i],
sizeof (GFC_UINTEGER_8));
get->base_addr[SZ * GFC_DESCRIPTOR_STRIDE(get, 0)] = rs->p;
}
else
{
__gthread_mutex_lock (&random_lock);
/* From the standard: "If no argument is present, the processor assigns
a processor-dependent value to the seed." */
if (size == NULL && put == NULL && get == NULL)
{
master_init = false;
init_rand_state (rs, true);
}
if (put != NULL)
{
/* If the rank of the array is not 1, abort. */
if (GFC_DESCRIPTOR_RANK (put) != 1)
runtime_error ("Array rank of PUT is not 1.");
/* If the array is too small, abort. */
if (GFC_DESCRIPTOR_EXTENT(put,0) < (index_type) SZ + 1)
runtime_error ("Array size of PUT is too small.");
/* This code now should do correct strides. */
for (size_t i = 0; i < SZ; i++)
memcpy (&seed[i], &(put->base_addr[i * GFC_DESCRIPTOR_STRIDE(put,0)]),
sizeof (GFC_UINTEGER_8));
scramble_seed (master_state, seed);
njumps = 0;
master_init = true;
init_rand_state (rs, true);
rs->p = put->base_addr[SZ * GFC_DESCRIPTOR_STRIDE(put, 0)] & 15;
}
__gthread_mutex_unlock (&random_lock);
}
}
iexport(random_seed_i8);
#if !defined __GTHREAD_MUTEX_INIT || defined __GTHREADS
static void __attribute__((constructor))
constructor_random (void)
{
#ifndef __GTHREAD_MUTEX_INIT
__GTHREAD_MUTEX_INIT_FUNCTION (&random_lock);
#endif
if (__gthread_active_p ())
__gthread_key_create (&rand_state_key, &free);
}
#endif
#ifdef __GTHREADS
static void __attribute__((destructor))
destructor_random (void)
{
if (__gthread_active_p ())
__gthread_key_delete (rand_state_key);
}
#endif