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|
///////////////////////////////////////////////////////////////
// Copyright 2012 John Maddock. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_
//
// Comparison operators for cpp_int_backend:
//
#ifndef BOOST_MP_CPP_INT_MUL_HPP
#define BOOST_MP_CPP_INT_MUL_HPP
namespace boost{ namespace multiprecision{ namespace backends{
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4127) // conditional expression is constant
#endif
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2>
inline typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value >::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>& a,
const limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
if(!val)
{
result = static_cast<limb_type>(0);
return;
}
if((void*)&a != (void*)&result)
result.resize(a.size(), a.size());
double_limb_type carry = 0;
typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::limb_pointer p = result.limbs();
typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::limb_pointer pe = result.limbs() + result.size();
typename cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>::const_limb_pointer pa = a.limbs();
while(p != pe)
{
carry += static_cast<double_limb_type>(*pa) * static_cast<double_limb_type>(val);
#ifdef __MSVC_RUNTIME_CHECKS
*p = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
#else
*p = static_cast<limb_type>(carry);
#endif
carry >>= cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::limb_bits;
++p, ++pa;
}
if(carry)
{
unsigned i = result.size();
result.resize(i + 1, i + 1);
if(result.size() > i)
result.limbs()[i] = static_cast<limb_type>(carry);
}
result.sign(a.sign());
if(!cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::variable)
result.normalize();
}
//
// resize_for_carry forces a resize of the underlying buffer only if a previous request
// for "required" elements could possibly have failed, *and* we have checking enabled.
// This will cause an overflow error inside resize():
//
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
inline void resize_for_carry(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& /*result*/, unsigned /*required*/){}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
inline void resize_for_carry(cpp_int_backend<MinBits1, MaxBits1, SignType1, checked, void>& result, unsigned required)
{
if(result.size() != required)
result.resize(required, required);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2, unsigned MinBits3, unsigned MaxBits3, cpp_integer_type SignType3, cpp_int_check_type Checked3, class Allocator3>
inline typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits3, MaxBits3, SignType3, Checked3, Allocator3> >::value >::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>& a,
const cpp_int_backend<MinBits3, MaxBits3, SignType3, Checked3, Allocator3>& b) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
// Very simple long multiplication, only usable for small numbers of limb_type's
// but that's the typical use case for this type anyway:
//
// Special cases first:
//
unsigned as = a.size();
unsigned bs = b.size();
typename cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>::const_limb_pointer pa = a.limbs();
typename cpp_int_backend<MinBits3, MaxBits3, SignType3, Checked3, Allocator3>::const_limb_pointer pb = b.limbs();
if(as == 1)
{
bool s = b.sign() != a.sign();
if(bs == 1)
{
result = static_cast<double_limb_type>(*pa) * static_cast<double_limb_type>(*pb);
}
else
{
limb_type l = *pa;
eval_multiply(result, b, l);
}
result.sign(s);
return;
}
if(bs == 1)
{
bool s = b.sign() != a.sign();
limb_type l = *pb;
eval_multiply(result, a, l);
result.sign(s);
return;
}
if((void*)&result == (void*)&a)
{
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> t(a);
eval_multiply(result, t, b);
return;
}
if((void*)&result == (void*)&b)
{
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> t(b);
eval_multiply(result, a, t);
return;
}
result.resize(as + bs, as + bs - 1);
typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::limb_pointer pr = result.limbs();
static const double_limb_type limb_max = ~static_cast<limb_type>(0u);
static const double_limb_type double_limb_max = ~static_cast<double_limb_type>(0u);
BOOST_STATIC_ASSERT(double_limb_max - 2 * limb_max >= limb_max * limb_max);
double_limb_type carry = 0;
std::memset(pr, 0, result.size() * sizeof(limb_type));
for(unsigned i = 0; i < as; ++i)
{
unsigned inner_limit = cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::variable ? bs : (std::min)(result.size() - i, bs);
for(unsigned j = 0; j < inner_limit; ++j)
{
BOOST_ASSERT(i+j < result.size());
#if (!defined(__GLIBCXX__) && !defined(__GLIBCPP__)) || !BOOST_WORKAROUND(BOOST_GCC_VERSION, <= 50100)
BOOST_ASSERT(!std::numeric_limits<double_limb_type>::is_specialized
|| ((std::numeric_limits<double_limb_type>::max)() - carry
>
static_cast<double_limb_type>(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::max_limb_value) * static_cast<double_limb_type>(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::max_limb_value)));
#endif
carry += static_cast<double_limb_type>(pa[i]) * static_cast<double_limb_type>(pb[j]);
BOOST_ASSERT(!std::numeric_limits<double_limb_type>::is_specialized || ((std::numeric_limits<double_limb_type>::max)() - carry >= pr[i+j]));
carry += pr[i + j];
#ifdef __MSVC_RUNTIME_CHECKS
pr[i + j] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
#else
pr[i + j] = static_cast<limb_type>(carry);
#endif
carry >>= cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::limb_bits;
BOOST_ASSERT(carry <= (cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::max_limb_value));
}
resize_for_carry(result, as + bs); // May throw if checking is enabled
if(i + bs < result.size())
pr[i + bs] = static_cast<limb_type>(carry);
carry = 0;
}
result.normalize();
//
// Set the sign of the result:
//
result.sign(a.sign() != b.sign());
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value >::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>& a) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
eval_multiply(result, result, a);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value>::type
eval_multiply(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result, const limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
eval_multiply(result, result, val);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value >::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>& a,
const double_limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
if(val <= (std::numeric_limits<limb_type>::max)())
{
eval_multiply(result, a, static_cast<limb_type>(val));
}
else
{
#if defined(BOOST_LITTLE_ENDIAN) && !defined(BOOST_MP_TEST_NO_LE)
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> t(val);
#else
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> t;
t = val;
#endif
eval_multiply(result, a, t);
}
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value>::type
eval_multiply(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result, const double_limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
eval_multiply(result, result, val);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value >::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>& a,
const signed_limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
if(val > 0)
eval_multiply(result, a, static_cast<limb_type>(val));
else
{
eval_multiply(result, a, static_cast<limb_type>(boost::multiprecision::detail::unsigned_abs(val)));
result.negate();
}
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value>::type
eval_multiply(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result, const signed_limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
eval_multiply(result, result, val);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2>
inline typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value && !is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value >::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>& a,
const signed_double_limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
if(val > 0)
{
if(val <= (std::numeric_limits<limb_type>::max)())
{
eval_multiply(result, a, static_cast<limb_type>(val));
return;
}
}
else if(val >= -static_cast<signed_double_limb_type>((std::numeric_limits<limb_type>::max)()))
{
eval_multiply(result, a, static_cast<limb_type>(boost::multiprecision::detail::unsigned_abs(val)));
result.negate();
return;
}
#if defined(BOOST_LITTLE_ENDIAN) && !defined(BOOST_MP_TEST_NO_LE)
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> t(val);
#else
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> t;
t = val;
#endif
eval_multiply(result, a, t);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value>::type
eval_multiply(cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result, const signed_double_limb_type& val) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
eval_multiply(result, result, val);
}
//
// Now over again for trivial cpp_int's:
//
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<
is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& (is_signed_number<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
|| is_signed_number<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value)
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& o) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
*result.limbs() = detail::checked_multiply(*result.limbs(), *o.limbs(), typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::checked_type());
result.sign(result.sign() != o.sign());
result.normalize();
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<
is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& is_unsigned_number<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& o) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
*result.limbs() = detail::checked_multiply(*result.limbs(), *o.limbs(), typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::checked_type());
result.normalize();
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<
is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& (is_signed_number<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
|| is_signed_number<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value)
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& a,
const cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& b) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
*result.limbs() = detail::checked_multiply(*a.limbs(), *b.limbs(), typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::checked_type());
result.sign(a.sign() != b.sign());
result.normalize();
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<
is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& is_unsigned_number<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
const cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& a,
const cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& b) BOOST_MP_NOEXCEPT_IF((is_non_throwing_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value))
{
*result.limbs() = detail::checked_multiply(*a.limbs(), *b.limbs(), typename cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>::checked_type());
result.normalize();
}
//
// Special routines for multiplying two integers to obtain a multiprecision result:
//
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<
!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
signed_double_limb_type a, signed_double_limb_type b)
{
static const signed_double_limb_type mask = ~static_cast<limb_type>(0);
static const unsigned limb_bits = sizeof(limb_type) * CHAR_BIT;
bool s = false;
double_limb_type w, x, y, z;
if(a < 0)
{
a = -a;
s = true;
}
if(b < 0)
{
b = -b;
s = !s;
}
w = a & mask;
x = a >> limb_bits;
y = b & mask;
z = b >> limb_bits;
result.resize(4, 4);
limb_type* pr = result.limbs();
double_limb_type carry = w * y;
#ifdef __MSVC_RUNTIME_CHECKS
pr[0] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
carry >>= limb_bits;
carry += w * z + x * y;
pr[1] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
carry >>= limb_bits;
carry += x * z;
pr[2] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
pr[3] = static_cast<limb_type>(carry >> limb_bits);
#else
pr[0] = static_cast<limb_type>(carry);
carry >>= limb_bits;
carry += w * z + x * y;
pr[1] = static_cast<limb_type>(carry);
carry >>= limb_bits;
carry += x * z;
pr[2] = static_cast<limb_type>(carry);
pr[3] = static_cast<limb_type>(carry >> limb_bits);
#endif
result.sign(s);
result.normalize();
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1>
BOOST_MP_FORCEINLINE typename enable_if_c<
!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
double_limb_type a, double_limb_type b)
{
static const signed_double_limb_type mask = ~static_cast<limb_type>(0);
static const unsigned limb_bits = sizeof(limb_type) * CHAR_BIT;
double_limb_type w, x, y, z;
w = a & mask;
x = a >> limb_bits;
y = b & mask;
z = b >> limb_bits;
result.resize(4, 4);
limb_type* pr = result.limbs();
double_limb_type carry = w * y;
#ifdef __MSVC_RUNTIME_CHECKS
pr[0] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
carry >>= limb_bits;
carry += w * z;
pr[1] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
carry >>= limb_bits;
pr[2] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
carry = x * y + pr[1];
pr[1] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
carry >>= limb_bits;
carry += pr[2] + x * z;
pr[2] = static_cast<limb_type>(carry & ~static_cast<limb_type>(0));
pr[3] = static_cast<limb_type>(carry >> limb_bits);
#else
pr[0] = static_cast<limb_type>(carry);
carry >>= limb_bits;
carry += w * z;
pr[1] = static_cast<limb_type>(carry);
carry >>= limb_bits;
pr[2] = static_cast<limb_type>(carry);
carry = x * y + pr[1];
pr[1] = static_cast<limb_type>(carry);
carry >>= limb_bits;
carry += pr[2] + x * z;
pr[2] = static_cast<limb_type>(carry);
pr[3] = static_cast<limb_type>(carry >> limb_bits);
#endif
result.sign(false);
result.normalize();
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1,
unsigned MinBits2, unsigned MaxBits2, cpp_integer_type SignType2, cpp_int_check_type Checked2, class Allocator2>
BOOST_MP_FORCEINLINE typename enable_if_c<
!is_trivial_cpp_int<cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::value
&& is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value
&& is_trivial_cpp_int<cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> >::value
>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> const& a,
cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2> const& b)
{
typedef typename boost::multiprecision::detail::canonical<typename cpp_int_backend<MinBits2, MaxBits2, SignType2, Checked2, Allocator2>::local_limb_type, cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1> >::type canonical_type;
eval_multiply(result, static_cast<canonical_type>(*a.limbs()), static_cast<canonical_type>(*b.limbs()));
result.sign(a.sign() != b.sign());
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, class SI>
BOOST_MP_FORCEINLINE typename enable_if_c<is_signed<SI>::value && (sizeof(SI) <= sizeof(signed_double_limb_type) / 2)>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
SI a, SI b)
{
result = static_cast<signed_double_limb_type>(a) * static_cast<signed_double_limb_type>(b);
}
template <unsigned MinBits1, unsigned MaxBits1, cpp_integer_type SignType1, cpp_int_check_type Checked1, class Allocator1, class UI>
BOOST_MP_FORCEINLINE typename enable_if_c<is_unsigned<UI>::value && (sizeof(UI) <= sizeof(signed_double_limb_type) / 2)>::type
eval_multiply(
cpp_int_backend<MinBits1, MaxBits1, SignType1, Checked1, Allocator1>& result,
UI a, UI b)
{
result = static_cast<double_limb_type>(a) * static_cast<double_limb_type>(b);
}
#ifdef _MSC_VER
#pragma warning(pop)
#endif
}}} // namespaces
#endif
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