/usr/include/x86_64-linux-gnu/c++/8/x32/bits/opt_random.h is in libx32stdc++-8-dev 8-20180414-1ubuntu2.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 | // Optimizations for random number functions, x86 version -*- C++ -*-
// Copyright (C) 2012-2018 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
// any later version.
// This library 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/>.
/** @file bits/opt_random.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{random}
*/
#ifndef _BITS_OPT_RANDOM_H
#define _BITS_OPT_RANDOM_H 1
#ifdef __SSE3__
#include <pmmintrin.h>
#endif
#pragma GCC system_header
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#ifdef __SSE3__
template<>
template<typename _UniformRandomNumberGenerator>
void
normal_distribution<double>::
__generate(typename normal_distribution<double>::result_type* __f,
typename normal_distribution<double>::result_type* __t,
_UniformRandomNumberGenerator& __urng,
const param_type& __param)
{
typedef uint64_t __uctype;
if (__f == __t)
return;
if (_M_saved_available)
{
_M_saved_available = false;
*__f++ = _M_saved * __param.stddev() + __param.mean();
if (__f == __t)
return;
}
constexpr uint64_t __maskval = 0xfffffffffffffull;
static const __m128i __mask = _mm_set1_epi64x(__maskval);
static const __m128i __two = _mm_set1_epi64x(0x4000000000000000ull);
static const __m128d __three = _mm_set1_pd(3.0);
const __m128d __av = _mm_set1_pd(__param.mean());
const __uctype __urngmin = __urng.min();
const __uctype __urngmax = __urng.max();
const __uctype __urngrange = __urngmax - __urngmin;
const __uctype __uerngrange = __urngrange + 1;
while (__f + 1 < __t)
{
double __le;
__m128d __x;
do
{
union
{
__m128i __i;
__m128d __d;
} __v;
if (__urngrange > __maskval)
{
if (__detail::_Power_of_2(__uerngrange))
__v.__i = _mm_and_si128(_mm_set_epi64x(__urng(),
__urng()),
__mask);
else
{
const __uctype __uerange = __maskval + 1;
const __uctype __scaling = __urngrange / __uerange;
const __uctype __past = __uerange * __scaling;
uint64_t __v1;
do
__v1 = __uctype(__urng()) - __urngmin;
while (__v1 >= __past);
__v1 /= __scaling;
uint64_t __v2;
do
__v2 = __uctype(__urng()) - __urngmin;
while (__v2 >= __past);
__v2 /= __scaling;
__v.__i = _mm_set_epi64x(__v1, __v2);
}
}
else if (__urngrange == __maskval)
__v.__i = _mm_set_epi64x(__urng(), __urng());
else if ((__urngrange + 2) * __urngrange >= __maskval
&& __detail::_Power_of_2(__uerngrange))
{
uint64_t __v1 = __urng() * __uerngrange + __urng();
uint64_t __v2 = __urng() * __uerngrange + __urng();
__v.__i = _mm_and_si128(_mm_set_epi64x(__v1, __v2),
__mask);
}
else
{
size_t __nrng = 2;
__uctype __high = __maskval / __uerngrange / __uerngrange;
while (__high > __uerngrange)
{
++__nrng;
__high /= __uerngrange;
}
const __uctype __highrange = __high + 1;
const __uctype __scaling = __urngrange / __highrange;
const __uctype __past = __highrange * __scaling;
__uctype __tmp;
uint64_t __v1;
do
{
do
__tmp = __uctype(__urng()) - __urngmin;
while (__tmp >= __past);
__v1 = __tmp / __scaling;
for (size_t __cnt = 0; __cnt < __nrng; ++__cnt)
{
__tmp = __v1;
__v1 *= __uerngrange;
__v1 += __uctype(__urng()) - __urngmin;
}
}
while (__v1 > __maskval || __v1 < __tmp);
uint64_t __v2;
do
{
do
__tmp = __uctype(__urng()) - __urngmin;
while (__tmp >= __past);
__v2 = __tmp / __scaling;
for (size_t __cnt = 0; __cnt < __nrng; ++__cnt)
{
__tmp = __v2;
__v2 *= __uerngrange;
__v2 += __uctype(__urng()) - __urngmin;
}
}
while (__v2 > __maskval || __v2 < __tmp);
__v.__i = _mm_set_epi64x(__v1, __v2);
}
__v.__i = _mm_or_si128(__v.__i, __two);
__x = _mm_sub_pd(__v.__d, __three);
__m128d __m = _mm_mul_pd(__x, __x);
__le = _mm_cvtsd_f64(_mm_hadd_pd (__m, __m));
}
while (__le == 0.0 || __le >= 1.0);
double __mult = (std::sqrt(-2.0 * std::log(__le) / __le)
* __param.stddev());
__x = _mm_add_pd(_mm_mul_pd(__x, _mm_set1_pd(__mult)), __av);
_mm_storeu_pd(__f, __x);
__f += 2;
}
if (__f != __t)
{
result_type __x, __y, __r2;
__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
__aurng(__urng);
do
{
__x = result_type(2.0) * __aurng() - 1.0;
__y = result_type(2.0) * __aurng() - 1.0;
__r2 = __x * __x + __y * __y;
}
while (__r2 > 1.0 || __r2 == 0.0);
const result_type __mult = std::sqrt(-2 * std::log(__r2) / __r2);
_M_saved = __x * __mult;
_M_saved_available = true;
*__f = __y * __mult * __param.stddev() + __param.mean();
}
}
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif // _BITS_OPT_RANDOM_H
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