GOSTCoin CUDA miner project, compatible with most nvidia cards, containing only gostd algo
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/*
* 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