block/include/nil/crypto3/detail/basic_functions.hpp

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//---------------------------------------------------------------------------//
// Copyright (c) 2018-2020 Mikhail Komarov <nemo@nil.foundation>
//
// MIT License
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//---------------------------------------------------------------------------//
 
#ifndef CRYPTO3_BASIC_FUNCTIONS_HPP
#define CRYPTO3_BASIC_FUNCTIONS_HPP
 
#include <boost/integer.hpp>
#include <boost/static_assert.hpp>
 
#include <nil/crypto3/detail/make_uint_t.hpp>
 
namespace nil {
    namespace crypto3 {
        namespace detail {
            template<std::size_t WordBits>
            struct basic_functions {
                constexpr static const std::size_t byte_bits = CHAR_BIT;
                typedef typename boost::uint_t<byte_bits>::exact byte_type;
 
                constexpr static const std::size_t word_bits = WordBits;
                typedef typename boost::uint_t<word_bits>::exact word_type;
 
                static inline word_type shr(word_type x, std::size_t n) {
                    return x >> n;
                }
 
                template<std::size_t n>
                static inline word_type shr(word_type x) {
                    BOOST_STATIC_ASSERT(n < word_bits);
                    return x >> n;
                }
 
                static inline word_type shl(word_type x, std::size_t n) {
                    return x << n;
                }
 
                template<std::size_t n>
                static inline word_type shl(word_type x) {
                    BOOST_STATIC_ASSERT(n < word_bits);
                    return x << n;
                }
 
                static inline word_type rotr(word_type x, std::size_t n) {
                    return shr(x, n) | shl(x, word_bits - n);
                }
 
                template<std::size_t n>
                static inline word_type rotr(word_type x) {
                    return shr<n>(x) | shl<word_bits - n>(x);
                }
 
                static inline word_type rotl(word_type x, std::size_t n) {
                    return shl(x, n) | shr(x, word_bits - n);
                }
 
                template<std::size_t n>
                static inline word_type rotl(word_type x) {
                    return shl<n>(x) | shr<word_bits - n>(x);
                }
            };
 
            template<>
            struct basic_functions<32> {
                constexpr static const std::size_t byte_bits = CHAR_BIT;
                typedef typename boost::uint_t<byte_bits>::exact byte_type;
 
                constexpr static const std::size_t word_bits = 32;
                typedef typename boost::uint_t<word_bits>::exact word_type;
 
                static inline word_type shr(word_type x, std::size_t n) {
                    return x >> n;
                }
 
                template<std::size_t n>
                static inline word_type shr(word_type x) {
                    BOOST_STATIC_ASSERT(n < word_bits);
                    return x >> n;
                }
 
                static inline word_type shl(word_type x, std::size_t n) {
                    return x << n;
                }
 
                template<std::size_t n>
                static inline word_type shl(word_type x) {
                    BOOST_STATIC_ASSERT(n < word_bits);
                    return x << n;
                }
 
                static inline word_type rotr(word_type x, std::size_t n) {
#if defined(BOOST_ARCH_X86)
                    asm("rorl %1,%0" : "+r"(x) : "c"(static_cast<uint8_t>(n)));
                    return x;
#else
                    return shr(x, n) | shl(x, word_bits - n);
#endif
                }
 
                template<std::size_t n>
                static inline word_type rotr(word_type x) {
                    return shr<n>(x) | shl<word_bits - n>(x);
                }
 
                static inline word_type rotl(word_type x, std::size_t n) {
#if defined(BOOST_ARCH_X86)
                    asm("roll %1,%0" : "+r"(x) : "c"(static_cast<uint8_t>(n)));
                    return x;
#else
                    return shl(x, n) | shr(x, word_bits - n);
#endif
                }
 
                template<std::size_t n>
                static inline word_type rotl(word_type x) {
                    return shl<n>(x) | shr<word_bits - n>(x);
                }
            };
        }    // namespace detail
    }        // namespace crypto3
}    // namespace nil
 
#endif    // CRYPTO3_BASIC_FUNCTIONS_HPP