mirror of https://github.com/GOSTSec/ccminer
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
108 lines
3.1 KiB
108 lines
3.1 KiB
11 years ago
|
/*
|
||
|
* Copyright 2008-2012 NVIDIA Corporation
|
||
|
*
|
||
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
* you may not use this file except in compliance with the License.
|
||
|
* You may obtain a copy of the License at
|
||
|
*
|
||
|
* http://www.apache.org/licenses/LICENSE-2.0
|
||
|
*
|
||
|
* Unless required by applicable law or agreed to in writing, software
|
||
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
* See the License for the specific language governing permissions and
|
||
|
* limitations under the License.
|
||
|
*/
|
||
|
|
||
|
#pragma once
|
||
|
|
||
|
#include <thrust/detail/cstdint.h>
|
||
|
#include <thrust/random/detail/mod.h>
|
||
|
|
||
|
namespace thrust
|
||
|
{
|
||
|
|
||
|
namespace random
|
||
|
{
|
||
|
|
||
|
namespace detail
|
||
|
{
|
||
|
|
||
|
|
||
|
template<typename UIntType, UIntType a, unsigned long long c, UIntType m>
|
||
|
struct linear_congruential_engine_discard_implementation
|
||
|
{
|
||
|
__host__ __device__
|
||
|
static void discard(UIntType &state, unsigned long long z)
|
||
|
{
|
||
|
for(; z > 0; --z)
|
||
|
{
|
||
|
state = detail::mod<UIntType,a,c,m>(state);
|
||
|
}
|
||
|
}
|
||
|
}; // end linear_congruential_engine_discard
|
||
|
|
||
|
|
||
|
// specialize for small integers and c == 0
|
||
|
// XXX figure out a robust implemenation of this for any unsigned integer type later
|
||
|
template<thrust::detail::uint32_t a, thrust::detail::uint32_t m>
|
||
|
struct linear_congruential_engine_discard_implementation<thrust::detail::uint32_t,a,0,m>
|
||
|
{
|
||
|
__host__ __device__
|
||
|
static void discard(thrust::detail::uint32_t &state, unsigned long long z)
|
||
|
{
|
||
|
const thrust::detail::uint32_t modulus = m;
|
||
|
|
||
|
// XXX we need to use unsigned long long here or we will encounter overflow in the
|
||
|
// multiplies below
|
||
|
// figure out a robust implementation of this later
|
||
|
unsigned long long multiplier = a;
|
||
|
unsigned long long multiplier_to_z = 1;
|
||
|
|
||
|
// see http://en.wikipedia.org/wiki/Modular_exponentiation
|
||
|
while(z > 0)
|
||
|
{
|
||
|
if(z & 1)
|
||
|
{
|
||
|
// multiply in this bit's contribution while using modulus to keep result small
|
||
|
multiplier_to_z = (multiplier_to_z * multiplier) % modulus;
|
||
|
}
|
||
|
|
||
|
// move to the next bit of the exponent, square (and mod) the base accordingly
|
||
|
z >>= 1;
|
||
|
multiplier = (multiplier * multiplier) % modulus;
|
||
|
}
|
||
|
|
||
|
state = static_cast<thrust::detail::uint32_t>((multiplier_to_z * state) % modulus);
|
||
|
}
|
||
|
}; // end linear_congruential_engine_discard
|
||
|
|
||
|
|
||
|
struct linear_congruential_engine_discard
|
||
|
{
|
||
|
template<typename LinearCongruentialEngine>
|
||
|
__host__ __device__
|
||
|
static void discard(LinearCongruentialEngine &lcg, unsigned long long z)
|
||
|
{
|
||
|
typedef typename LinearCongruentialEngine::result_type result_type;
|
||
|
const result_type c = LinearCongruentialEngine::increment;
|
||
|
const result_type a = LinearCongruentialEngine::multiplier;
|
||
|
const result_type m = LinearCongruentialEngine::modulus;
|
||
|
|
||
|
// XXX WAR unused variable warnings
|
||
|
(void) c;
|
||
|
(void) a;
|
||
|
(void) m;
|
||
|
|
||
|
linear_congruential_engine_discard_implementation<result_type,a,c,m>::discard(lcg.m_x, z);
|
||
|
}
|
||
|
}; // end linear_congruential_engine_discard
|
||
|
|
||
|
|
||
|
} // end detail
|
||
|
|
||
|
} // end random
|
||
|
|
||
|
} // end thrust
|
||
|
|