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1 ///////////////////////////////////////////////////////////////////////////////
2 // Copyright Christopher Kormanyos 2002 - 2013.
3 // Copyright 2011 -2013 John Maddock. Distributed under the Boost
4 // Software License, Version 1.0. (See accompanying file
5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 // This work is based on an earlier work:
8 // "Algorithm 910: A Portable C++ Multiple-Precision System for Special-Function Calculations",
9 // in ACM TOMS, {VOL 37, ISSUE 4, (February 2011)} (C) ACM, 2011. http://doi.acm.org/10.1145/1916461.1916469
10 //
11 // Note that there are no "noexcept" specifications on the functions in this file: there are too many
12 // calls to lexical_cast (and similar) to easily analyse the code for correctness. So until compilers
13 // can detect noexcept misuse at compile time, the only realistic option is to simply not use it here.
14 //
15 
16 #ifndef BOOST_MP_CPP_DEC_FLOAT_BACKEND_HPP
17 #define BOOST_MP_CPP_DEC_FLOAT_BACKEND_HPP
18 
19 #include <boost/config.hpp>
20 #include <boost/cstdint.hpp>
21 #include <limits>
22 #ifndef BOOST_NO_CXX11_HDR_ARRAY
23 #include <array>
24 #else
25 #include <boost/array.hpp>
26 #endif
27 #include <boost/cstdint.hpp>
28 #include <boost/functional/hash_fwd.hpp>
29 #include <boost/multiprecision/number.hpp>
30 #include <boost/multiprecision/detail/big_lanczos.hpp>
31 #include <boost/multiprecision/detail/dynamic_array.hpp>
32 #include <boost/multiprecision/detail/itos.hpp>
33 
34 //
35 // Headers required for Boost.Math integration:
36 //
37 #include <boost/math/policies/policy.hpp>
38 //
39 // Some includes we need from Boost.Math, since we rely on that library to provide these functions:
40 //
41 #include <boost/math/special_functions/asinh.hpp>
42 #include <boost/math/special_functions/acosh.hpp>
43 #include <boost/math/special_functions/atanh.hpp>
44 #include <boost/math/special_functions/cbrt.hpp>
45 #include <boost/math/special_functions/expm1.hpp>
46 #include <boost/math/special_functions/gamma.hpp>
47 
48 #ifdef BOOST_MSVC
49 #pragma warning(push)
50 #pragma warning(disable : 6326) // comparison of two constants
51 #endif
52 
53 namespace boost {
54 namespace multiprecision {
55 namespace backends {
56 
57 template <unsigned Digits10, class ExponentType = boost::int32_t, class Allocator = void>
58 class cpp_dec_float;
59 
60 } // namespace backends
61 
62 template <unsigned Digits10, class ExponentType, class Allocator>
63 struct number_category<backends::cpp_dec_float<Digits10, ExponentType, Allocator> > : public mpl::int_<number_kind_floating_point>
64 {};
65 
66 namespace backends {
67 
68 template <unsigned Digits10, class ExponentType, class Allocator>
69 class cpp_dec_float
70 {
71  private:
72    static const boost::int32_t cpp_dec_float_digits10_setting = Digits10;
73 
74    // We need at least 16-bits in the exponent type to do anything sensible:
75    BOOST_STATIC_ASSERT_MSG(boost::is_signed<ExponentType>::value, "ExponentType must be a signed built in integer type.");
76    BOOST_STATIC_ASSERT_MSG(sizeof(ExponentType) > 1, "ExponentType is too small.");
77 
78  public:
79    typedef mpl::list<boost::long_long_type>  signed_types;
80    typedef mpl::list<boost::ulong_long_type> unsigned_types;
81    typedef mpl::list<double, long double>    float_types;
82    typedef ExponentType                      exponent_type;
83 
84    static const boost::int32_t cpp_dec_float_radix             = 10L;
85    static const boost::int32_t cpp_dec_float_digits10_limit_lo = 9L;
86    static const boost::int32_t cpp_dec_float_digits10_limit_hi = boost::integer_traits<boost::int32_t>::const_max - 100;
87    static const boost::int32_t cpp_dec_float_digits10          = ((cpp_dec_float_digits10_setting < cpp_dec_float_digits10_limit_lo) ? cpp_dec_float_digits10_limit_lo : ((cpp_dec_float_digits10_setting > cpp_dec_float_digits10_limit_hi) ? cpp_dec_float_digits10_limit_hi : cpp_dec_float_digits10_setting));
88    static const ExponentType   cpp_dec_float_max_exp10         = (static_cast<ExponentType>(1) << (std::numeric_limits<ExponentType>::digits - 5));
89    static const ExponentType   cpp_dec_float_min_exp10         = -cpp_dec_float_max_exp10;
90    static const ExponentType   cpp_dec_float_max_exp           = cpp_dec_float_max_exp10;
91    static const ExponentType   cpp_dec_float_min_exp           = cpp_dec_float_min_exp10;
92 
93    BOOST_STATIC_ASSERT((cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_max_exp10 == -cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_min_exp10));
94 
95  private:
96    static const boost::int32_t cpp_dec_float_elem_digits10 = 8L;
97    static const boost::int32_t cpp_dec_float_elem_mask     = 100000000L;
98 
99    BOOST_STATIC_ASSERT(0 == cpp_dec_float_max_exp10 % cpp_dec_float_elem_digits10);
100 
101    // There are three guard limbs.
102    // 1) The first limb has 'play' from 1...8 decimal digits.
103    // 2) The last limb also has 'play' from 1...8 decimal digits.
104    // 3) One limb can get lost when justifying after multiply,
105    // as only half of the triangle is multiplied and a carry
106    // from below is missing.
107    static const boost::int32_t cpp_dec_float_elem_number_request = static_cast<boost::int32_t>((cpp_dec_float_digits10 / cpp_dec_float_elem_digits10) + (((cpp_dec_float_digits10 % cpp_dec_float_elem_digits10) != 0) ? 1 : 0));
108 
109    // The number of elements needed (with a minimum of two) plus three added guard limbs.
110    static const boost::int32_t cpp_dec_float_elem_number = static_cast<boost::int32_t>(((cpp_dec_float_elem_number_request < 2L) ? 2L : cpp_dec_float_elem_number_request) + 3L);
111 
112  public:
113    static const boost::int32_t cpp_dec_float_total_digits10 = static_cast<boost::int32_t>(cpp_dec_float_elem_number * cpp_dec_float_elem_digits10);
114 
115  private:
116    typedef enum enum_fpclass_type
117    {
118       cpp_dec_float_finite,
119       cpp_dec_float_inf,
120       cpp_dec_float_NaN
121    } fpclass_type;
122 
123 #ifndef BOOST_NO_CXX11_HDR_ARRAY
124    typedef typename mpl::if_<is_void<Allocator>,
125                              std::array<boost::uint32_t, cpp_dec_float_elem_number>,
126                              detail::dynamic_array<boost::uint32_t, cpp_dec_float_elem_number, Allocator> >::type array_type;
127 #else
128    typedef typename mpl::if_<is_void<Allocator>,
129                              boost::array<boost::uint32_t, cpp_dec_float_elem_number>,
130                              detail::dynamic_array<boost::uint32_t, cpp_dec_float_elem_number, Allocator> >::type array_type;
131 #endif
132 
133    array_type     data;
134    ExponentType   exp;
135    bool           neg;
136    fpclass_type   fpclass;
137    boost::int32_t prec_elem;
138 
139    //
140    // Special values constructor:
141    //
cpp_dec_float(fpclass_type c)142    cpp_dec_float(fpclass_type c) : data(),
143                                    exp(static_cast<ExponentType>(0)),
144                                    neg(false),
145                                    fpclass(c),
146                                    prec_elem(cpp_dec_float_elem_number) {}
147 
148    //
149    // Static data initializer:
150    //
151    struct initializer
152    {
initializerboost::multiprecision::backends::cpp_dec_float::initializer153       initializer()
154       {
155          cpp_dec_float<Digits10, ExponentType, Allocator>::nan();
156          cpp_dec_float<Digits10, ExponentType, Allocator>::inf();
157          (cpp_dec_float<Digits10, ExponentType, Allocator>::min)();
158          (cpp_dec_float<Digits10, ExponentType, Allocator>::max)();
159          cpp_dec_float<Digits10, ExponentType, Allocator>::zero();
160          cpp_dec_float<Digits10, ExponentType, Allocator>::one();
161          cpp_dec_float<Digits10, ExponentType, Allocator>::two();
162          cpp_dec_float<Digits10, ExponentType, Allocator>::half();
163          cpp_dec_float<Digits10, ExponentType, Allocator>::double_min();
164          cpp_dec_float<Digits10, ExponentType, Allocator>::double_max();
165          //cpp_dec_float<Digits10, ExponentType, Allocator>::long_double_max();
166          //cpp_dec_float<Digits10, ExponentType, Allocator>::long_double_min();
167          cpp_dec_float<Digits10, ExponentType, Allocator>::long_long_max();
168          cpp_dec_float<Digits10, ExponentType, Allocator>::long_long_min();
169          cpp_dec_float<Digits10, ExponentType, Allocator>::ulong_long_max();
170          cpp_dec_float<Digits10, ExponentType, Allocator>::eps();
171          cpp_dec_float<Digits10, ExponentType, Allocator>::pow2(0);
172       }
do_nothingboost::multiprecision::backends::cpp_dec_float::initializer173       void do_nothing() {}
174    };
175 
176    static initializer init;
177 
178    struct long_double_initializer
179    {
long_double_initializerboost::multiprecision::backends::cpp_dec_float::long_double_initializer180       long_double_initializer()
181       {
182          cpp_dec_float<Digits10, ExponentType, Allocator>::long_double_max();
183          cpp_dec_float<Digits10, ExponentType, Allocator>::long_double_min();
184       }
do_nothingboost::multiprecision::backends::cpp_dec_float::long_double_initializer185       void do_nothing() {}
186    };
187 
188    static long_double_initializer linit;
189 
190  public:
191    // Constructors
BOOST_MP_NOEXCEPT_IF(noexcept (array_type ()))192    cpp_dec_float() BOOST_MP_NOEXCEPT_IF(noexcept(array_type())) : data(),
193                                                                   exp(static_cast<ExponentType>(0)),
194                                                                   neg(false),
195                                                                   fpclass(cpp_dec_float_finite),
196                                                                   prec_elem(cpp_dec_float_elem_number) {}
197 
cpp_dec_float(const char * s)198    cpp_dec_float(const char* s) : data(),
199                                   exp(static_cast<ExponentType>(0)),
200                                   neg(false),
201                                   fpclass(cpp_dec_float_finite),
202                                   prec_elem(cpp_dec_float_elem_number)
203    {
204       *this = s;
205    }
206 
207    template <class I>
cpp_dec_float(I i,typename enable_if<is_unsigned<I>>::type * =0)208    cpp_dec_float(I i, typename enable_if<is_unsigned<I> >::type* = 0) : data(),
209                                                                         exp(static_cast<ExponentType>(0)),
210                                                                         neg(false),
211                                                                         fpclass(cpp_dec_float_finite),
212                                                                         prec_elem(cpp_dec_float_elem_number)
213    {
214       from_unsigned_long_long(i);
215    }
216 
217    template <class I>
cpp_dec_float(I i,typename enable_if<is_signed<I>>::type * =0)218    cpp_dec_float(I i, typename enable_if<is_signed<I> >::type* = 0) : data(),
219                                                                       exp(static_cast<ExponentType>(0)),
220                                                                       neg(false),
221                                                                       fpclass(cpp_dec_float_finite),
222                                                                       prec_elem(cpp_dec_float_elem_number)
223    {
224       if (i < 0)
225       {
226          from_unsigned_long_long(boost::multiprecision::detail::unsigned_abs(i));
227          negate();
228       }
229       else
230          from_unsigned_long_long(i);
231    }
232 
BOOST_MP_NOEXCEPT_IF(noexcept (array_type (std::declval<const array_type &> ())))233    cpp_dec_float(const cpp_dec_float& f) BOOST_MP_NOEXCEPT_IF(noexcept(array_type(std::declval<const array_type&>()))) : data(f.data),
234                                                                                                                          exp(f.exp),
235                                                                                                                          neg(f.neg),
236                                                                                                                          fpclass(f.fpclass),
237                                                                                                                          prec_elem(f.prec_elem) {}
238 
239    template <unsigned D, class ET, class A>
cpp_dec_float(const cpp_dec_float<D,ET,A> & f,typename enable_if_c<D<=Digits10>::type * =0)240    cpp_dec_float(const cpp_dec_float<D, ET, A>& f, typename enable_if_c<D <= Digits10>::type* = 0) : data(),
241                                                                                                      exp(f.exp),
242                                                                                                      neg(f.neg),
243                                                                                                      fpclass(static_cast<fpclass_type>(static_cast<int>(f.fpclass))),
244                                                                                                      prec_elem(cpp_dec_float_elem_number)
245    {
246       std::copy(f.data.begin(), f.data.begin() + f.prec_elem, data.begin());
247    }
248    template <unsigned D, class ET, class A>
cpp_dec_float(const cpp_dec_float<D,ET,A> & f,typename disable_if_c<D<=Digits10>::type * =0)249    explicit cpp_dec_float(const cpp_dec_float<D, ET, A>& f, typename disable_if_c<D <= Digits10>::type* = 0) : data(),
250                                                                                                                exp(f.exp),
251                                                                                                                neg(f.neg),
252                                                                                                                fpclass(static_cast<fpclass_type>(static_cast<int>(f.fpclass))),
253                                                                                                                prec_elem(cpp_dec_float_elem_number)
254    {
255       // TODO: this doesn't round!
256       std::copy(f.data.begin(), f.data.begin() + prec_elem, data.begin());
257    }
258 
259    template <class F>
cpp_dec_float(const F val,typename enable_if_c<is_floating_point<F>::value &&!boost::is_same<F,__float128>::value>::type * =0)260    cpp_dec_float(const F val, typename enable_if_c<is_floating_point<F>::value
261 #ifdef BOOST_HAS_FLOAT128
262                                                    && !boost::is_same<F, __float128>::value
263 #endif
264                                                    >::type* = 0) : data(),
265                                                                    exp(static_cast<ExponentType>(0)),
266                                                                    neg(false),
267                                                                    fpclass(cpp_dec_float_finite),
268                                                                    prec_elem(cpp_dec_float_elem_number)
269    {
270       *this = val;
271    }
272 
273    cpp_dec_float(const double mantissa, const ExponentType exponent);
274 
hash() const275    std::size_t hash() const
276    {
277       std::size_t result = 0;
278       for (int i = 0; i < prec_elem; ++i)
279          boost::hash_combine(result, data[i]);
280       boost::hash_combine(result, exp);
281       boost::hash_combine(result, neg);
282       boost::hash_combine(result, fpclass);
283       return result;
284    }
285 
286    // Specific special values.
nan()287    static const cpp_dec_float& nan()
288    {
289       static const cpp_dec_float val(cpp_dec_float_NaN);
290       init.do_nothing();
291       return val;
292    }
293 
inf()294    static const cpp_dec_float& inf()
295    {
296       static const cpp_dec_float val(cpp_dec_float_inf);
297       init.do_nothing();
298       return val;
299    }
300 
301    static const cpp_dec_float&(max)()
302    {
303       init.do_nothing();
304       static cpp_dec_float val_max = std::string("1.0e" + boost::multiprecision::detail::itos(cpp_dec_float_max_exp10)).c_str();
305       return val_max;
306    }
307 
308    static const cpp_dec_float&(min)()
309    {
310       init.do_nothing();
311       static cpp_dec_float val_min = std::string("1.0e" + boost::multiprecision::detail::itos(cpp_dec_float_min_exp10)).c_str();
312       return val_min;
313    }
314 
zero()315    static const cpp_dec_float& zero()
316    {
317       init.do_nothing();
318       static cpp_dec_float val(static_cast<boost::ulong_long_type>(0u));
319       return val;
320    }
321 
one()322    static const cpp_dec_float& one()
323    {
324       init.do_nothing();
325       static cpp_dec_float val(static_cast<boost::ulong_long_type>(1u));
326       return val;
327    }
328 
two()329    static const cpp_dec_float& two()
330    {
331       init.do_nothing();
332       static cpp_dec_float val(static_cast<boost::ulong_long_type>(2u));
333       return val;
334    }
335 
half()336    static const cpp_dec_float& half()
337    {
338       init.do_nothing();
339       static cpp_dec_float val(0.5L);
340       return val;
341    }
342 
double_min()343    static const cpp_dec_float& double_min()
344    {
345       init.do_nothing();
346       static cpp_dec_float val((std::numeric_limits<double>::min)());
347       return val;
348    }
349 
double_max()350    static const cpp_dec_float& double_max()
351    {
352       init.do_nothing();
353       static cpp_dec_float val((std::numeric_limits<double>::max)());
354       return val;
355    }
356 
long_double_min()357    static const cpp_dec_float& long_double_min()
358    {
359       linit.do_nothing();
360 #ifdef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
361       static cpp_dec_float val(static_cast<long double>((std::numeric_limits<double>::min)()));
362 #else
363       static cpp_dec_float val((std::numeric_limits<long double>::min)());
364 #endif
365       return val;
366    }
367 
long_double_max()368    static const cpp_dec_float& long_double_max()
369    {
370        linit.do_nothing();
371 #ifdef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
372       static cpp_dec_float val(static_cast<long double>((std::numeric_limits<double>::max)()));
373 #else
374       static cpp_dec_float val((std::numeric_limits<long double>::max)());
375 #endif
376       return val;
377    }
378 
long_long_max()379    static const cpp_dec_float& long_long_max()
380    {
381       init.do_nothing();
382       static cpp_dec_float val((std::numeric_limits<boost::long_long_type>::max)());
383       return val;
384    }
385 
long_long_min()386    static const cpp_dec_float& long_long_min()
387    {
388       init.do_nothing();
389       static cpp_dec_float val((std::numeric_limits<boost::long_long_type>::min)());
390       return val;
391    }
392 
ulong_long_max()393    static const cpp_dec_float& ulong_long_max()
394    {
395       init.do_nothing();
396       static cpp_dec_float val((std::numeric_limits<boost::ulong_long_type>::max)());
397       return val;
398    }
399 
eps()400    static const cpp_dec_float& eps()
401    {
402       init.do_nothing();
403       static cpp_dec_float val(1.0, 1 - static_cast<int>(cpp_dec_float_digits10));
404       return val;
405    }
406 
407    // Basic operations.
operator =(const cpp_dec_float & v)408    cpp_dec_float& operator=(const cpp_dec_float& v) BOOST_MP_NOEXCEPT_IF(noexcept(std::declval<array_type&>() = std::declval<const array_type&>()))
409    {
410       data      = v.data;
411       exp       = v.exp;
412       neg       = v.neg;
413       fpclass   = v.fpclass;
414       prec_elem = v.prec_elem;
415       return *this;
416    }
417 
418    template <unsigned D>
operator =(const cpp_dec_float<D> & f)419    cpp_dec_float& operator=(const cpp_dec_float<D>& f)
420    {
421       exp            = f.exp;
422       neg            = f.neg;
423       fpclass        = static_cast<enum_fpclass_type>(static_cast<int>(f.fpclass));
424       unsigned elems = (std::min)(f.prec_elem, cpp_dec_float_elem_number);
425       std::copy(f.data.begin(), f.data.begin() + elems, data.begin());
426       std::fill(data.begin() + elems, data.end(), 0);
427       prec_elem = cpp_dec_float_elem_number;
428       return *this;
429    }
430 
operator =(boost::long_long_type v)431    cpp_dec_float& operator=(boost::long_long_type v)
432    {
433       if (v < 0)
434       {
435          from_unsigned_long_long(1u - boost::ulong_long_type(v + 1)); // Avoid undefined behaviour in negation of minimum value for long long
436          negate();
437       }
438       else
439          from_unsigned_long_long(v);
440       return *this;
441    }
442 
operator =(boost::ulong_long_type v)443    cpp_dec_float& operator=(boost::ulong_long_type v)
444    {
445       from_unsigned_long_long(v);
446       return *this;
447    }
448 
449    template <class Float>
450    typename boost::enable_if_c<boost::is_floating_point<Float>::value, cpp_dec_float&>::type operator=(Float v);
451 
operator =(const char * v)452    cpp_dec_float& operator=(const char* v)
453    {
454       rd_string(v);
455       return *this;
456    }
457 
458    cpp_dec_float& operator+=(const cpp_dec_float& v);
459    cpp_dec_float& operator-=(const cpp_dec_float& v);
460    cpp_dec_float& operator*=(const cpp_dec_float& v);
461    cpp_dec_float& operator/=(const cpp_dec_float& v);
462 
add_unsigned_long_long(const boost::ulong_long_type n)463    cpp_dec_float& add_unsigned_long_long(const boost::ulong_long_type n)
464    {
465       cpp_dec_float t;
466       t.from_unsigned_long_long(n);
467       return *this += t;
468    }
469 
sub_unsigned_long_long(const boost::ulong_long_type n)470    cpp_dec_float& sub_unsigned_long_long(const boost::ulong_long_type n)
471    {
472       cpp_dec_float t;
473       t.from_unsigned_long_long(n);
474       return *this -= t;
475    }
476 
477    cpp_dec_float& mul_unsigned_long_long(const boost::ulong_long_type n);
478    cpp_dec_float& div_unsigned_long_long(const boost::ulong_long_type n);
479 
480    // Elementary primitives.
481    cpp_dec_float& calculate_inv();
482    cpp_dec_float& calculate_sqrt();
483 
negate()484    void negate()
485    {
486       if (!iszero())
487          neg = !neg;
488    }
489 
490    // Comparison functions
BOOST_PREVENT_MACRO_SUBSTITUTION() const491    bool isnan BOOST_PREVENT_MACRO_SUBSTITUTION() const { return (fpclass == cpp_dec_float_NaN); }
BOOST_PREVENT_MACRO_SUBSTITUTION() const492    bool isinf BOOST_PREVENT_MACRO_SUBSTITUTION() const { return (fpclass == cpp_dec_float_inf); }
BOOST_PREVENT_MACRO_SUBSTITUTION() const493    bool isfinite BOOST_PREVENT_MACRO_SUBSTITUTION() const { return (fpclass == cpp_dec_float_finite); }
494 
iszero() const495    bool iszero() const
496    {
497       return ((fpclass == cpp_dec_float_finite) && (data[0u] == 0u));
498    }
499 
500    bool isone() const;
501    bool isint() const;
isneg() const502    bool isneg() const { return neg; }
503 
504    // Operators pre-increment and pre-decrement
operator ++()505    cpp_dec_float& operator++()
506    {
507       return *this += one();
508    }
509 
operator --()510    cpp_dec_float& operator--()
511    {
512       return *this -= one();
513    }
514 
515    std::string str(boost::intmax_t digits, std::ios_base::fmtflags f) const;
516 
517    int compare(const cpp_dec_float& v) const;
518 
519    template <class V>
compare(const V & v) const520    int compare(const V& v) const
521    {
522       cpp_dec_float<Digits10, ExponentType, Allocator> t;
523       t = v;
524       return compare(t);
525    }
526 
swap(cpp_dec_float & v)527    void swap(cpp_dec_float& v)
528    {
529       data.swap(v.data);
530       std::swap(exp, v.exp);
531       std::swap(neg, v.neg);
532       std::swap(fpclass, v.fpclass);
533       std::swap(prec_elem, v.prec_elem);
534    }
535 
536    double                 extract_double() const;
537    long double            extract_long_double() const;
538    boost::long_long_type  extract_signed_long_long() const;
539    boost::ulong_long_type extract_unsigned_long_long() const;
540    void                   extract_parts(double& mantissa, ExponentType& exponent) const;
541    cpp_dec_float          extract_integer_part() const;
542 
precision(const boost::int32_t prec_digits)543    void precision(const boost::int32_t prec_digits)
544    {
545       if (prec_digits >= cpp_dec_float_total_digits10)
546       {
547          prec_elem = cpp_dec_float_elem_number;
548       }
549       else
550       {
551          const boost::int32_t elems = static_cast<boost::int32_t>(static_cast<boost::int32_t>((prec_digits + (cpp_dec_float_elem_digits10 / 2)) / cpp_dec_float_elem_digits10) + static_cast<boost::int32_t>(((prec_digits % cpp_dec_float_elem_digits10) != 0) ? 1 : 0));
552 
553          prec_elem = (std::min)(cpp_dec_float_elem_number, (std::max)(elems, static_cast<boost::int32_t>(2)));
554       }
555    }
556    static cpp_dec_float pow2(boost::long_long_type i);
order() const557    ExponentType         order() const
558    {
559       const bool bo_order_is_zero = ((!(isfinite)()) || (data[0] == static_cast<boost::uint32_t>(0u)));
560       //
561       // Binary search to find the order of the leading term:
562       //
563       ExponentType prefix = 0;
564 
565       if (data[0] >= 100000UL)
566       {
567          if (data[0] >= 10000000UL)
568          {
569             if (data[0] >= 100000000UL)
570             {
571                if (data[0] >= 1000000000UL)
572                   prefix = 9;
573                else
574                   prefix = 8;
575             }
576             else
577                prefix = 7;
578          }
579          else
580          {
581             if (data[0] >= 1000000UL)
582                prefix = 6;
583             else
584                prefix = 5;
585          }
586       }
587       else
588       {
589          if (data[0] >= 1000UL)
590          {
591             if (data[0] >= 10000UL)
592                prefix = 4;
593             else
594                prefix = 3;
595          }
596          else
597          {
598             if (data[0] >= 100)
599                prefix = 2;
600             else if (data[0] >= 10)
601                prefix = 1;
602          }
603       }
604 
605       return (bo_order_is_zero ? static_cast<ExponentType>(0) : static_cast<ExponentType>(exp + prefix));
606    }
607 
608    template <class Archive>
serialize(Archive & ar,const unsigned int)609    void serialize(Archive& ar, const unsigned int /*version*/)
610    {
611       for (unsigned i = 0; i < data.size(); ++i)
612          ar& boost::make_nvp("digit", data[i]);
613       ar& boost::make_nvp("exponent", exp);
614       ar& boost::make_nvp("sign", neg);
615       ar& boost::make_nvp("class-type", fpclass);
616       ar& boost::make_nvp("precision", prec_elem);
617    }
618 
619  private:
data_elem_is_non_zero_predicate(const boost::uint32_t & d)620    static bool data_elem_is_non_zero_predicate(const boost::uint32_t& d) { return (d != static_cast<boost::uint32_t>(0u)); }
data_elem_is_non_nine_predicate(const boost::uint32_t & d)621    static bool data_elem_is_non_nine_predicate(const boost::uint32_t& d) { return (d != static_cast<boost::uint32_t>(cpp_dec_float::cpp_dec_float_elem_mask - 1)); }
char_is_nonzero_predicate(const char & c)622    static bool char_is_nonzero_predicate(const char& c) { return (c != static_cast<char>('0')); }
623 
624    void from_unsigned_long_long(const boost::ulong_long_type u);
625 
626    int cmp_data(const array_type& vd) const;
627 
628    static boost::uint32_t mul_loop_uv(boost::uint32_t* const u, const boost::uint32_t* const v, const boost::int32_t p);
629    static boost::uint32_t mul_loop_n(boost::uint32_t* const u, boost::uint32_t n, const boost::int32_t p);
630    static boost::uint32_t div_loop_n(boost::uint32_t* const u, boost::uint32_t n, const boost::int32_t p);
631 
632    bool rd_string(const char* const s);
633 
634    template <unsigned D, class ET, class A>
635    friend class cpp_dec_float;
636 };
637 
638 template <unsigned Digits10, class ExponentType, class Allocator>
639 typename cpp_dec_float<Digits10, ExponentType, Allocator>::initializer cpp_dec_float<Digits10, ExponentType, Allocator>::init;
640 template <unsigned Digits10, class ExponentType, class Allocator>
641 typename cpp_dec_float<Digits10, ExponentType, Allocator>::long_double_initializer cpp_dec_float<Digits10, ExponentType, Allocator>::linit;
642 
643 template <unsigned Digits10, class ExponentType, class Allocator>
644 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_radix;
645 template <unsigned Digits10, class ExponentType, class Allocator>
646 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10_setting;
647 template <unsigned Digits10, class ExponentType, class Allocator>
648 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10_limit_lo;
649 template <unsigned Digits10, class ExponentType, class Allocator>
650 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10_limit_hi;
651 template <unsigned Digits10, class ExponentType, class Allocator>
652 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10;
653 template <unsigned Digits10, class ExponentType, class Allocator>
654 const ExponentType cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_max_exp;
655 template <unsigned Digits10, class ExponentType, class Allocator>
656 const ExponentType cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_min_exp;
657 template <unsigned Digits10, class ExponentType, class Allocator>
658 const ExponentType cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_max_exp10;
659 template <unsigned Digits10, class ExponentType, class Allocator>
660 const ExponentType cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_min_exp10;
661 template <unsigned Digits10, class ExponentType, class Allocator>
662 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_elem_digits10;
663 template <unsigned Digits10, class ExponentType, class Allocator>
664 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_elem_number_request;
665 template <unsigned Digits10, class ExponentType, class Allocator>
666 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_elem_number;
667 template <unsigned Digits10, class ExponentType, class Allocator>
668 const boost::int32_t cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_elem_mask;
669 
670 template <unsigned Digits10, class ExponentType, class Allocator>
operator +=(const cpp_dec_float<Digits10,ExponentType,Allocator> & v)671 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::operator+=(const cpp_dec_float<Digits10, ExponentType, Allocator>& v)
672 {
673    if ((isnan)())
674    {
675       return *this;
676    }
677 
678    if ((isinf)())
679    {
680       if ((v.isinf)() && (isneg() != v.isneg()))
681       {
682          *this = nan();
683       }
684       return *this;
685    }
686 
687    if (iszero())
688    {
689       return operator=(v);
690    }
691 
692    if ((v.isnan)() || (v.isinf)())
693    {
694       *this = v;
695       return *this;
696    }
697 
698    // Get the offset for the add/sub operation.
699    static const ExponentType max_delta_exp = static_cast<ExponentType>((cpp_dec_float_elem_number - 1) * cpp_dec_float_elem_digits10);
700 
701    const ExponentType ofs_exp = static_cast<ExponentType>(exp - v.exp);
702 
703    // Check if the operation is out of range, requiring special handling.
704    if (v.iszero() || (ofs_exp > max_delta_exp))
705    {
706       // Result is *this unchanged since v is negligible compared to *this.
707       return *this;
708    }
709    else if (ofs_exp < -max_delta_exp)
710    {
711       // Result is *this = v since *this is negligible compared to v.
712       return operator=(v);
713    }
714 
715    // Do the add/sub operation.
716 
717    typename array_type::iterator       p_u    = data.begin();
718    typename array_type::const_iterator p_v    = v.data.begin();
719    bool                                b_copy = false;
720    const boost::int32_t                ofs    = static_cast<boost::int32_t>(static_cast<boost::int32_t>(ofs_exp) / cpp_dec_float_elem_digits10);
721    array_type                          n_data;
722 
723    if (neg == v.neg)
724    {
725       // Add v to *this, where the data array of either *this or v
726       // might have to be treated with a positive, negative or zero offset.
727       // The result is stored in *this. The data are added one element
728       // at a time, each element with carry.
729       if (ofs >= static_cast<boost::int32_t>(0))
730       {
731          std::copy(v.data.begin(), v.data.end() - static_cast<size_t>(ofs), n_data.begin() + static_cast<size_t>(ofs));
732          std::fill(n_data.begin(), n_data.begin() + static_cast<size_t>(ofs), static_cast<boost::uint32_t>(0u));
733          p_v = n_data.begin();
734       }
735       else
736       {
737          std::copy(data.begin(), data.end() - static_cast<size_t>(-ofs), n_data.begin() + static_cast<size_t>(-ofs));
738          std::fill(n_data.begin(), n_data.begin() + static_cast<size_t>(-ofs), static_cast<boost::uint32_t>(0u));
739          p_u    = n_data.begin();
740          b_copy = true;
741       }
742 
743       // Addition algorithm
744       boost::uint32_t carry = static_cast<boost::uint32_t>(0u);
745 
746       for (boost::int32_t j = static_cast<boost::int32_t>(cpp_dec_float_elem_number - static_cast<boost::int32_t>(1)); j >= static_cast<boost::int32_t>(0); j--)
747       {
748          boost::uint32_t t = static_cast<boost::uint32_t>(static_cast<boost::uint32_t>(p_u[j] + p_v[j]) + carry);
749          carry             = t / static_cast<boost::uint32_t>(cpp_dec_float_elem_mask);
750          p_u[j]            = static_cast<boost::uint32_t>(t - static_cast<boost::uint32_t>(carry * static_cast<boost::uint32_t>(cpp_dec_float_elem_mask)));
751       }
752 
753       if (b_copy)
754       {
755          data = n_data;
756          exp  = v.exp;
757       }
758 
759       // There needs to be a carry into the element -1 of the array data
760       if (carry != static_cast<boost::uint32_t>(0u))
761       {
762          std::copy_backward(data.begin(), data.end() - static_cast<std::size_t>(1u), data.end());
763          data[0] = carry;
764          exp += static_cast<ExponentType>(cpp_dec_float_elem_digits10);
765       }
766    }
767    else
768    {
769       // Subtract v from *this, where the data array of either *this or v
770       // might have to be treated with a positive, negative or zero offset.
771       if ((ofs > static_cast<boost::int32_t>(0)) || ((ofs == static_cast<boost::int32_t>(0)) && (cmp_data(v.data) > static_cast<boost::int32_t>(0))))
772       {
773          // In this case, |u| > |v| and ofs is positive.
774          // Copy the data of v, shifted down to a lower value
775          // into the data array m_n. Set the operand pointer p_v
776          // to point to the copied, shifted data m_n.
777          std::copy(v.data.begin(), v.data.end() - static_cast<size_t>(ofs), n_data.begin() + static_cast<size_t>(ofs));
778          std::fill(n_data.begin(), n_data.begin() + static_cast<size_t>(ofs), static_cast<boost::uint32_t>(0u));
779          p_v = n_data.begin();
780       }
781       else
782       {
783          if (ofs != static_cast<boost::int32_t>(0))
784          {
785             // In this case, |u| < |v| and ofs is negative.
786             // Shift the data of u down to a lower value.
787             std::copy_backward(data.begin(), data.end() - static_cast<size_t>(-ofs), data.end());
788             std::fill(data.begin(), data.begin() + static_cast<size_t>(-ofs), static_cast<boost::uint32_t>(0u));
789          }
790 
791          // Copy the data of v into the data array n_data.
792          // Set the u-pointer p_u to point to m_n and the
793          // operand pointer p_v to point to the shifted
794          // data m_data.
795          n_data = v.data;
796          p_u    = n_data.begin();
797          p_v    = data.begin();
798          b_copy = true;
799       }
800 
801       boost::int32_t j;
802 
803       // Subtraction algorithm
804       boost::int32_t borrow = static_cast<boost::int32_t>(0);
805 
806       for (j = static_cast<boost::int32_t>(cpp_dec_float_elem_number - static_cast<boost::int32_t>(1)); j >= static_cast<boost::int32_t>(0); j--)
807       {
808          boost::int32_t t = static_cast<boost::int32_t>(static_cast<boost::int32_t>(static_cast<boost::int32_t>(p_u[j]) - static_cast<boost::int32_t>(p_v[j])) - borrow);
809 
810          // Underflow? Borrow?
811          if (t < static_cast<boost::int32_t>(0))
812          {
813             // Yes, underflow and borrow
814             t += static_cast<boost::int32_t>(cpp_dec_float_elem_mask);
815             borrow = static_cast<boost::int32_t>(1);
816          }
817          else
818          {
819             borrow = static_cast<boost::int32_t>(0);
820          }
821 
822          p_u[j] = static_cast<boost::uint32_t>(static_cast<boost::uint32_t>(t) % static_cast<boost::uint32_t>(cpp_dec_float_elem_mask));
823       }
824 
825       if (b_copy)
826       {
827          data = n_data;
828          exp  = v.exp;
829          neg  = v.neg;
830       }
831 
832       // Is it necessary to justify the data?
833       const typename array_type::const_iterator first_nonzero_elem = std::find_if(data.begin(), data.end(), data_elem_is_non_zero_predicate);
834 
835       if (first_nonzero_elem != data.begin())
836       {
837          if (first_nonzero_elem == data.end())
838          {
839             // This result of the subtraction is exactly zero.
840             // Reset the sign and the exponent.
841             neg = false;
842             exp = static_cast<ExponentType>(0);
843          }
844          else
845          {
846             // Justify the data
847             const std::size_t sj = static_cast<std::size_t>(std::distance<typename array_type::const_iterator>(data.begin(), first_nonzero_elem));
848 
849             std::copy(data.begin() + static_cast<std::size_t>(sj), data.end(), data.begin());
850             std::fill(data.end() - sj, data.end(), static_cast<boost::uint32_t>(0u));
851 
852             exp -= static_cast<ExponentType>(sj * static_cast<std::size_t>(cpp_dec_float_elem_digits10));
853          }
854       }
855    }
856 
857    // Handle underflow.
858    if (iszero())
859       return (*this = zero());
860 
861    // Check for potential overflow.
862    const bool b_result_might_overflow = (exp >= static_cast<ExponentType>(cpp_dec_float_max_exp10));
863 
864    // Handle overflow.
865    if (b_result_might_overflow)
866    {
867       const bool b_result_is_neg = neg;
868       neg                        = false;
869 
870       if (compare((cpp_dec_float::max)()) > 0)
871          *this = inf();
872 
873       neg = b_result_is_neg;
874    }
875 
876    return *this;
877 }
878 
879 template <unsigned Digits10, class ExponentType, class Allocator>
operator -=(const cpp_dec_float<Digits10,ExponentType,Allocator> & v)880 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::operator-=(const cpp_dec_float<Digits10, ExponentType, Allocator>& v)
881 {
882    // Use *this - v = -(-*this + v).
883    negate();
884    *this += v;
885    negate();
886    return *this;
887 }
888 
889 template <unsigned Digits10, class ExponentType, class Allocator>
operator *=(const cpp_dec_float<Digits10,ExponentType,Allocator> & v)890 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::operator*=(const cpp_dec_float<Digits10, ExponentType, Allocator>& v)
891 {
892    // Evaluate the sign of the result.
893    const bool b_result_is_neg = (neg != v.neg);
894 
895    // Artificially set the sign of the result to be positive.
896    neg = false;
897 
898    // Handle special cases like zero, inf and NaN.
899    const bool b_u_is_inf  = (isinf)();
900    const bool b_v_is_inf  = (v.isinf)();
901    const bool b_u_is_zero = iszero();
902    const bool b_v_is_zero = v.iszero();
903 
904    if (((isnan)() || (v.isnan)()) || (b_u_is_inf && b_v_is_zero) || (b_v_is_inf && b_u_is_zero))
905    {
906       *this = nan();
907       return *this;
908    }
909 
910    if (b_u_is_inf || b_v_is_inf)
911    {
912       *this = inf();
913       if (b_result_is_neg)
914          negate();
915       return *this;
916    }
917 
918    if (b_u_is_zero || b_v_is_zero)
919    {
920       return *this = zero();
921    }
922 
923    // Check for potential overflow or underflow.
924    const bool b_result_might_overflow  = ((exp + v.exp) >= static_cast<ExponentType>(cpp_dec_float_max_exp10));
925    const bool b_result_might_underflow = ((exp + v.exp) <= static_cast<ExponentType>(cpp_dec_float_min_exp10));
926 
927    // Set the exponent of the result.
928    exp += v.exp;
929 
930    const boost::int32_t prec_mul = (std::min)(prec_elem, v.prec_elem);
931 
932    const boost::uint32_t carry = mul_loop_uv(data.data(), v.data.data(), prec_mul);
933 
934    // Handle a potential carry.
935    if (carry != static_cast<boost::uint32_t>(0u))
936    {
937       exp += cpp_dec_float_elem_digits10;
938 
939       // Shift the result of the multiplication one element to the right...
940       std::copy_backward(data.begin(),
941                          data.begin() + static_cast<std::size_t>(prec_elem - static_cast<boost::int32_t>(1)),
942                          data.begin() + static_cast<std::size_t>(prec_elem));
943 
944       // ... And insert the carry.
945       data.front() = carry;
946    }
947 
948    // Handle overflow.
949    if (b_result_might_overflow && (compare((cpp_dec_float::max)()) > 0))
950    {
951       *this = inf();
952    }
953 
954    // Handle underflow.
955    if (b_result_might_underflow && (compare((cpp_dec_float::min)()) < 0))
956    {
957       *this = zero();
958 
959       return *this;
960    }
961 
962    // Set the sign of the result.
963    neg = b_result_is_neg;
964 
965    return *this;
966 }
967 
968 template <unsigned Digits10, class ExponentType, class Allocator>
operator /=(const cpp_dec_float<Digits10,ExponentType,Allocator> & v)969 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::operator/=(const cpp_dec_float<Digits10, ExponentType, Allocator>& v)
970 {
971    if (iszero())
972    {
973       if ((v.isnan)())
974       {
975          return *this = v;
976       }
977       else if (v.iszero())
978       {
979          return *this = nan();
980       }
981    }
982 
983    const bool u_and_v_are_finite_and_identical = ((isfinite)() && (fpclass == v.fpclass) && (exp == v.exp) && (cmp_data(v.data) == static_cast<boost::int32_t>(0)));
984 
985    if (u_and_v_are_finite_and_identical)
986    {
987       if (neg != v.neg)
988       {
989          *this = one();
990          negate();
991       }
992       else
993          *this = one();
994       return *this;
995    }
996    else
997    {
998       cpp_dec_float t(v);
999       t.calculate_inv();
1000       return operator*=(t);
1001    }
1002 }
1003 
1004 template <unsigned Digits10, class ExponentType, class Allocator>
mul_unsigned_long_long(const boost::ulong_long_type n)1005 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::mul_unsigned_long_long(const boost::ulong_long_type n)
1006 {
1007    // Multiply *this with a constant boost::ulong_long_type.
1008 
1009    // Evaluate the sign of the result.
1010    const bool b_neg = neg;
1011 
1012    // Artificially set the sign of the result to be positive.
1013    neg = false;
1014 
1015    // Handle special cases like zero, inf and NaN.
1016    const bool b_u_is_inf  = (isinf)();
1017    const bool b_n_is_zero = (n == static_cast<boost::int32_t>(0));
1018 
1019    if ((isnan)() || (b_u_is_inf && b_n_is_zero))
1020    {
1021       return (*this = nan());
1022    }
1023 
1024    if (b_u_is_inf)
1025    {
1026       *this = inf();
1027       if (b_neg)
1028          negate();
1029       return *this;
1030    }
1031 
1032    if (iszero() || b_n_is_zero)
1033    {
1034       // Multiplication by zero.
1035       return *this = zero();
1036    }
1037 
1038    if (n >= static_cast<boost::ulong_long_type>(cpp_dec_float_elem_mask))
1039    {
1040       neg = b_neg;
1041       cpp_dec_float t;
1042       t = n;
1043       return operator*=(t);
1044    }
1045 
1046    if (n == static_cast<boost::ulong_long_type>(1u))
1047    {
1048       neg = b_neg;
1049       return *this;
1050    }
1051 
1052    // Set up the multiplication loop.
1053    const boost::uint32_t nn    = static_cast<boost::uint32_t>(n);
1054    const boost::uint32_t carry = mul_loop_n(data.data(), nn, prec_elem);
1055 
1056    // Handle the carry and adjust the exponent.
1057    if (carry != static_cast<boost::uint32_t>(0u))
1058    {
1059       exp += static_cast<ExponentType>(cpp_dec_float_elem_digits10);
1060 
1061       // Shift the result of the multiplication one element to the right.
1062       std::copy_backward(data.begin(),
1063                          data.begin() + static_cast<std::size_t>(prec_elem - static_cast<boost::int32_t>(1)),
1064                          data.begin() + static_cast<std::size_t>(prec_elem));
1065 
1066       data.front() = static_cast<boost::uint32_t>(carry);
1067    }
1068 
1069    // Check for potential overflow.
1070    const bool b_result_might_overflow = (exp >= cpp_dec_float_max_exp10);
1071 
1072    // Handle overflow.
1073    if (b_result_might_overflow && (compare((cpp_dec_float::max)()) > 0))
1074    {
1075       *this = inf();
1076    }
1077 
1078    // Set the sign.
1079    neg = b_neg;
1080 
1081    return *this;
1082 }
1083 
1084 template <unsigned Digits10, class ExponentType, class Allocator>
div_unsigned_long_long(const boost::ulong_long_type n)1085 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::div_unsigned_long_long(const boost::ulong_long_type n)
1086 {
1087    // Divide *this by a constant boost::ulong_long_type.
1088 
1089    // Evaluate the sign of the result.
1090    const bool b_neg = neg;
1091 
1092    // Artificially set the sign of the result to be positive.
1093    neg = false;
1094 
1095    // Handle special cases like zero, inf and NaN.
1096    if ((isnan)())
1097    {
1098       return *this;
1099    }
1100 
1101    if ((isinf)())
1102    {
1103       *this = inf();
1104       if (b_neg)
1105          negate();
1106       return *this;
1107    }
1108 
1109    if (n == static_cast<boost::ulong_long_type>(0u))
1110    {
1111       // Divide by 0.
1112       if (iszero())
1113       {
1114          *this = nan();
1115          return *this;
1116       }
1117       else
1118       {
1119          *this = inf();
1120          if (isneg())
1121             negate();
1122          return *this;
1123       }
1124    }
1125 
1126    if (iszero())
1127    {
1128       return *this;
1129    }
1130 
1131    if (n >= static_cast<boost::ulong_long_type>(cpp_dec_float_elem_mask))
1132    {
1133       neg = b_neg;
1134       cpp_dec_float t;
1135       t = n;
1136       return operator/=(t);
1137    }
1138 
1139    const boost::uint32_t nn = static_cast<boost::uint32_t>(n);
1140 
1141    if (nn > static_cast<boost::uint32_t>(1u))
1142    {
1143       // Do the division loop.
1144       const boost::uint32_t prev = div_loop_n(data.data(), nn, prec_elem);
1145 
1146       // Determine if one leading zero is in the result data.
1147       if (data[0] == static_cast<boost::uint32_t>(0u))
1148       {
1149          // Adjust the exponent
1150          exp -= static_cast<ExponentType>(cpp_dec_float_elem_digits10);
1151 
1152          // Shift result of the division one element to the left.
1153          std::copy(data.begin() + static_cast<std::size_t>(1u),
1154                    data.begin() + static_cast<std::size_t>(prec_elem - static_cast<boost::int32_t>(1)),
1155                    data.begin());
1156 
1157          data[prec_elem - static_cast<boost::int32_t>(1)] = static_cast<boost::uint32_t>(static_cast<boost::uint64_t>(prev * static_cast<boost::uint64_t>(cpp_dec_float_elem_mask)) / nn);
1158       }
1159    }
1160 
1161    // Check for potential underflow.
1162    const bool b_result_might_underflow = (exp <= cpp_dec_float_min_exp10);
1163 
1164    // Handle underflow.
1165    if (b_result_might_underflow && (compare((cpp_dec_float::min)()) < 0))
1166       return (*this = zero());
1167 
1168    // Set the sign of the result.
1169    neg = b_neg;
1170 
1171    return *this;
1172 }
1173 
1174 template <unsigned Digits10, class ExponentType, class Allocator>
calculate_inv()1175 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::calculate_inv()
1176 {
1177    // Compute the inverse of *this.
1178    const bool b_neg = neg;
1179 
1180    neg = false;
1181 
1182    // Handle special cases like zero, inf and NaN.
1183    if (iszero())
1184    {
1185       *this = inf();
1186       if (b_neg)
1187          negate();
1188       return *this;
1189    }
1190 
1191    if ((isnan)())
1192    {
1193       return *this;
1194    }
1195 
1196    if ((isinf)())
1197    {
1198       return *this = zero();
1199    }
1200 
1201    if (isone())
1202    {
1203       if (b_neg)
1204          negate();
1205       return *this;
1206    }
1207 
1208    // Save the original *this.
1209    cpp_dec_float<Digits10, ExponentType, Allocator> x(*this);
1210 
1211    // Generate the initial estimate using division.
1212    // Extract the mantissa and exponent for a "manual"
1213    // computation of the estimate.
1214    double       dd;
1215    ExponentType ne;
1216    x.extract_parts(dd, ne);
1217 
1218    // Do the inverse estimate using double precision estimates of mantissa and exponent.
1219    operator=(cpp_dec_float<Digits10, ExponentType, Allocator>(1.0 / dd, -ne));
1220 
1221    // Compute the inverse of *this. Quadratically convergent Newton-Raphson iteration
1222    // is used. During the iterative steps, the precision of the calculation is limited
1223    // to the minimum required in order to minimize the run-time.
1224 
1225    static const boost::int32_t double_digits10_minus_a_few = std::numeric_limits<double>::digits10 - 3;
1226 
1227    for (boost::int32_t digits = double_digits10_minus_a_few; digits <= cpp_dec_float_total_digits10; digits *= static_cast<boost::int32_t>(2))
1228    {
1229       // Adjust precision of the terms.
1230       precision(static_cast<boost::int32_t>((digits + 10) * static_cast<boost::int32_t>(2)));
1231       x.precision(static_cast<boost::int32_t>((digits + 10) * static_cast<boost::int32_t>(2)));
1232 
1233       // Next iteration.
1234       cpp_dec_float t(*this);
1235       t *= x;
1236       t -= two();
1237       t.negate();
1238       *this *= t;
1239    }
1240 
1241    neg = b_neg;
1242 
1243    prec_elem = cpp_dec_float_elem_number;
1244 
1245    return *this;
1246 }
1247 
1248 template <unsigned Digits10, class ExponentType, class Allocator>
calculate_sqrt()1249 cpp_dec_float<Digits10, ExponentType, Allocator>& cpp_dec_float<Digits10, ExponentType, Allocator>::calculate_sqrt()
1250 {
1251    // Compute the square root of *this.
1252 
1253    if ((isinf)() && !isneg())
1254    {
1255       return *this;
1256    }
1257 
1258    if (isneg() || (!(isfinite)()))
1259    {
1260       *this = nan();
1261       errno = EDOM;
1262       return *this;
1263    }
1264 
1265    if (iszero() || isone())
1266    {
1267       return *this;
1268    }
1269 
1270    // Save the original *this.
1271    cpp_dec_float<Digits10, ExponentType, Allocator> x(*this);
1272 
1273    // Generate the initial estimate using division.
1274    // Extract the mantissa and exponent for a "manual"
1275    // computation of the estimate.
1276    double       dd;
1277    ExponentType ne;
1278    extract_parts(dd, ne);
1279 
1280    // Force the exponent to be an even multiple of two.
1281    if ((ne % static_cast<ExponentType>(2)) != static_cast<ExponentType>(0))
1282    {
1283       ++ne;
1284       dd /= 10.0;
1285    }
1286 
1287    // Setup the iteration.
1288    // Estimate the square root using simple manipulations.
1289    const double sqd = std::sqrt(dd);
1290 
1291    *this = cpp_dec_float<Digits10, ExponentType, Allocator>(sqd, static_cast<ExponentType>(ne / static_cast<ExponentType>(2)));
1292 
1293    // Estimate 1.0 / (2.0 * x0) using simple manipulations.
1294    cpp_dec_float<Digits10, ExponentType, Allocator> vi(0.5 / sqd, static_cast<ExponentType>(-ne / static_cast<ExponentType>(2)));
1295 
1296    // Compute the square root of x. Coupled Newton iteration
1297    // as described in "Pi Unleashed" is used. During the
1298    // iterative steps, the precision of the calculation is
1299    // limited to the minimum required in order to minimize
1300    // the run-time.
1301    //
1302    // Book references:
1303    // https://doi.org/10.1007/978-3-642-56735-3
1304    // http://www.amazon.com/exec/obidos/tg/detail/-/3540665722/qid=1035535482/sr=8-7/ref=sr_8_7/104-3357872-6059916?v=glance&n=507846
1305 
1306    static const boost::uint32_t double_digits10_minus_a_few = std::numeric_limits<double>::digits10 - 3;
1307 
1308    for (boost::int32_t digits = double_digits10_minus_a_few; digits <= cpp_dec_float_total_digits10; digits *= 2u)
1309    {
1310       // Adjust precision of the terms.
1311       precision((digits + 10) * 2);
1312       vi.precision((digits + 10) * 2);
1313 
1314       // Next iteration of vi
1315       cpp_dec_float t(*this);
1316       t *= vi;
1317       t.negate();
1318       t.mul_unsigned_long_long(2u);
1319       t += one();
1320       t *= vi;
1321       vi += t;
1322 
1323       // Next iteration of *this
1324       t = *this;
1325       t *= *this;
1326       t.negate();
1327       t += x;
1328       t *= vi;
1329       *this += t;
1330    }
1331 
1332    prec_elem = cpp_dec_float_elem_number;
1333 
1334    return *this;
1335 }
1336 
1337 template <unsigned Digits10, class ExponentType, class Allocator>
cmp_data(const array_type & vd) const1338 int cpp_dec_float<Digits10, ExponentType, Allocator>::cmp_data(const array_type& vd) const
1339 {
1340    // Compare the data of *this with those of v.
1341    // Return +1 for *this > v
1342    // 0 for *this = v
1343    // -1 for *this < v
1344 
1345    const std::pair<typename array_type::const_iterator, typename array_type::const_iterator> mismatch_pair = std::mismatch(data.begin(), data.end(), vd.begin());
1346 
1347    const bool is_equal = ((mismatch_pair.first == data.end()) && (mismatch_pair.second == vd.end()));
1348 
1349    if (is_equal)
1350    {
1351       return 0;
1352    }
1353    else
1354    {
1355       return ((*mismatch_pair.first > *mismatch_pair.second) ? 1 : -1);
1356    }
1357 }
1358 
1359 template <unsigned Digits10, class ExponentType, class Allocator>
compare(const cpp_dec_float & v) const1360 int cpp_dec_float<Digits10, ExponentType, Allocator>::compare(const cpp_dec_float& v) const
1361 {
1362    // Compare v with *this.
1363    // Return +1 for *this > v
1364    // 0 for *this = v
1365    // -1 for *this < v
1366 
1367    // Handle all non-finite cases.
1368    if ((!(isfinite)()) || (!(v.isfinite)()))
1369    {
1370       // NaN can never equal NaN. Return an implementation-dependent
1371       // signed result. Also note that comparison of NaN with NaN
1372       // using operators greater-than or less-than is undefined.
1373       if ((isnan)() || (v.isnan)())
1374       {
1375          return ((isnan)() ? 1 : -1);
1376       }
1377 
1378       if ((isinf)() && (v.isinf)())
1379       {
1380          // Both *this and v are infinite. They are equal if they have the same sign.
1381          // Otherwise, *this is less than v if and only if *this is negative.
1382          return ((neg == v.neg) ? 0 : (neg ? -1 : 1));
1383       }
1384 
1385       if ((isinf)())
1386       {
1387          // *this is infinite, but v is finite.
1388          // So negative infinite *this is less than any finite v.
1389          // Whereas positive infinite *this is greater than any finite v.
1390          return (isneg() ? -1 : 1);
1391       }
1392       else
1393       {
1394          // *this is finite, and v is infinite.
1395          // So any finite *this is greater than negative infinite v.
1396          // Whereas any finite *this is less than positive infinite v.
1397          return (v.neg ? 1 : -1);
1398       }
1399    }
1400 
1401    // And now handle all *finite* cases.
1402    if (iszero())
1403    {
1404       // The value of *this is zero and v is either zero or non-zero.
1405       return (v.iszero() ? 0
1406                          : (v.neg ? 1 : -1));
1407    }
1408    else if (v.iszero())
1409    {
1410       // The value of v is zero and *this is non-zero.
1411       return (neg ? -1 : 1);
1412    }
1413    else
1414    {
1415       // Both *this and v are non-zero.
1416 
1417       if (neg != v.neg)
1418       {
1419          // The signs are different.
1420          return (neg ? -1 : 1);
1421       }
1422       else if (exp != v.exp)
1423       {
1424          // The signs are the same and the exponents are different.
1425          const int val_cexpression = ((exp < v.exp) ? 1 : -1);
1426 
1427          return (neg ? val_cexpression : -val_cexpression);
1428       }
1429       else
1430       {
1431          // The signs are the same and the exponents are the same.
1432          // Compare the data.
1433          const int val_cmp_data = cmp_data(v.data);
1434 
1435          return ((!neg) ? val_cmp_data : -val_cmp_data);
1436       }
1437    }
1438 }
1439 
1440 template <unsigned Digits10, class ExponentType, class Allocator>
isone() const1441 bool cpp_dec_float<Digits10, ExponentType, Allocator>::isone() const
1442 {
1443    // Check if the value of *this is identically 1 or very close to 1.
1444 
1445    const bool not_negative_and_is_finite = ((!neg) && (isfinite)());
1446 
1447    if (not_negative_and_is_finite)
1448    {
1449       if ((data[0u] == static_cast<boost::uint32_t>(1u)) && (exp == static_cast<ExponentType>(0)))
1450       {
1451          const typename array_type::const_iterator it_non_zero = std::find_if(data.begin(), data.end(), data_elem_is_non_zero_predicate);
1452          return (it_non_zero == data.end());
1453       }
1454       else if ((data[0u] == static_cast<boost::uint32_t>(cpp_dec_float_elem_mask - 1)) && (exp == static_cast<ExponentType>(-cpp_dec_float_elem_digits10)))
1455       {
1456          const typename array_type::const_iterator it_non_nine = std::find_if(data.begin(), data.end(), data_elem_is_non_nine_predicate);
1457          return (it_non_nine == data.end());
1458       }
1459    }
1460 
1461    return false;
1462 }
1463 
1464 template <unsigned Digits10, class ExponentType, class Allocator>
isint() const1465 bool cpp_dec_float<Digits10, ExponentType, Allocator>::isint() const
1466 {
1467    if (fpclass != cpp_dec_float_finite)
1468    {
1469       return false;
1470    }
1471 
1472    if (iszero())
1473    {
1474       return true;
1475    }
1476 
1477    if (exp < static_cast<ExponentType>(0))
1478    {
1479       return false;
1480    } // |*this| < 1.
1481 
1482    const typename array_type::size_type offset_decimal_part = static_cast<typename array_type::size_type>(exp / cpp_dec_float_elem_digits10) + 1u;
1483 
1484    if (offset_decimal_part >= static_cast<typename array_type::size_type>(cpp_dec_float_elem_number))
1485    {
1486       // The number is too large to resolve the integer part.
1487       // It considered to be a pure integer.
1488       return true;
1489    }
1490 
1491    typename array_type::const_iterator it_non_zero = std::find_if(data.begin() + offset_decimal_part, data.end(), data_elem_is_non_zero_predicate);
1492 
1493    return (it_non_zero == data.end());
1494 }
1495 
1496 template <unsigned Digits10, class ExponentType, class Allocator>
extract_parts(double & mantissa,ExponentType & exponent) const1497 void cpp_dec_float<Digits10, ExponentType, Allocator>::extract_parts(double& mantissa, ExponentType& exponent) const
1498 {
1499    // Extract the approximate parts mantissa and base-10 exponent from the input cpp_dec_float<Digits10, ExponentType, Allocator> value x.
1500 
1501    // Extracts the mantissa and exponent.
1502    exponent = exp;
1503 
1504    boost::uint32_t p10  = static_cast<boost::uint32_t>(1u);
1505    boost::uint32_t test = data[0u];
1506 
1507    for (;;)
1508    {
1509       test /= static_cast<boost::uint32_t>(10u);
1510 
1511       if (test == static_cast<boost::uint32_t>(0u))
1512       {
1513          break;
1514       }
1515 
1516       p10 *= static_cast<boost::uint32_t>(10u);
1517       ++exponent;
1518    }
1519 
1520    // Establish the upper bound of limbs for extracting the double.
1521    const int max_elem_in_double_count = static_cast<int>(static_cast<boost::int32_t>(std::numeric_limits<double>::digits10) / cpp_dec_float_elem_digits10) + (static_cast<int>(static_cast<boost::int32_t>(std::numeric_limits<double>::digits10) % cpp_dec_float_elem_digits10) != 0 ? 1 : 0) + 1;
1522 
1523    // And make sure this upper bound stays within bounds of the elems.
1524    const std::size_t max_elem_extract_count = static_cast<std::size_t>((std::min)(static_cast<boost::int32_t>(max_elem_in_double_count), cpp_dec_float_elem_number));
1525 
1526    // Extract into the mantissa the first limb, extracted as a double.
1527    mantissa     = static_cast<double>(data[0]);
1528    double scale = 1.0;
1529 
1530    // Extract the rest of the mantissa piecewise from the limbs.
1531    for (std::size_t i = 1u; i < max_elem_extract_count; i++)
1532    {
1533       scale /= static_cast<double>(cpp_dec_float_elem_mask);
1534       mantissa += (static_cast<double>(data[i]) * scale);
1535    }
1536 
1537    mantissa /= static_cast<double>(p10);
1538 
1539    if (neg)
1540    {
1541       mantissa = -mantissa;
1542    }
1543 }
1544 
1545 template <unsigned Digits10, class ExponentType, class Allocator>
extract_double() const1546 double cpp_dec_float<Digits10, ExponentType, Allocator>::extract_double() const
1547 {
1548    // Returns the double conversion of a cpp_dec_float<Digits10, ExponentType, Allocator>.
1549 
1550    // Check for non-normal cpp_dec_float<Digits10, ExponentType, Allocator>.
1551    if (!(isfinite)())
1552    {
1553       if ((isnan)())
1554       {
1555          return std::numeric_limits<double>::quiet_NaN();
1556       }
1557       else
1558       {
1559          return ((!neg) ? std::numeric_limits<double>::infinity()
1560                         : -std::numeric_limits<double>::infinity());
1561       }
1562    }
1563 
1564    cpp_dec_float<Digits10, ExponentType, Allocator> xx(*this);
1565    if (xx.isneg())
1566       xx.negate();
1567 
1568    // Check if *this cpp_dec_float<Digits10, ExponentType, Allocator> is zero.
1569    if (iszero() || (xx.compare(double_min()) < 0))
1570    {
1571       return 0.0;
1572    }
1573 
1574    // Check if *this cpp_dec_float<Digits10, ExponentType, Allocator> exceeds the maximum of double.
1575    if (xx.compare(double_max()) > 0)
1576    {
1577       return ((!neg) ? std::numeric_limits<double>::infinity()
1578                      : -std::numeric_limits<double>::infinity());
1579    }
1580 
1581    std::stringstream ss;
1582    ss.imbue(std::locale::classic());
1583 
1584    ss << str(std::numeric_limits<double>::digits10 + (2 + 1), std::ios_base::scientific);
1585 
1586    double d;
1587    ss >> d;
1588 
1589    return d;
1590 }
1591 
1592 template <unsigned Digits10, class ExponentType, class Allocator>
extract_long_double() const1593 long double cpp_dec_float<Digits10, ExponentType, Allocator>::extract_long_double() const
1594 {
1595    // Returns the long double conversion of a cpp_dec_float<Digits10, ExponentType, Allocator>.
1596 
1597    // Check if *this cpp_dec_float<Digits10, ExponentType, Allocator> is subnormal.
1598    if (!(isfinite)())
1599    {
1600       if ((isnan)())
1601       {
1602          return std::numeric_limits<long double>::quiet_NaN();
1603       }
1604       else
1605       {
1606          return ((!neg) ? std::numeric_limits<long double>::infinity()
1607                         : -std::numeric_limits<long double>::infinity());
1608       }
1609    }
1610 
1611    cpp_dec_float<Digits10, ExponentType, Allocator> xx(*this);
1612    if (xx.isneg())
1613       xx.negate();
1614 
1615    // Check if *this cpp_dec_float<Digits10, ExponentType, Allocator> is zero.
1616    if (iszero() || (xx.compare(long_double_min()) < 0))
1617    {
1618       return static_cast<long double>(0.0);
1619    }
1620 
1621    // Check if *this cpp_dec_float<Digits10, ExponentType, Allocator> exceeds the maximum of double.
1622    if (xx.compare(long_double_max()) > 0)
1623    {
1624       return ((!neg) ? std::numeric_limits<long double>::infinity()
1625                      : -std::numeric_limits<long double>::infinity());
1626    }
1627 
1628    std::stringstream ss;
1629    ss.imbue(std::locale::classic());
1630 
1631    ss << str(std::numeric_limits<long double>::digits10 + (2 + 1), std::ios_base::scientific);
1632 
1633    long double ld;
1634    ss >> ld;
1635 
1636    return ld;
1637 }
1638 
1639 template <unsigned Digits10, class ExponentType, class Allocator>
extract_signed_long_long() const1640 boost::long_long_type cpp_dec_float<Digits10, ExponentType, Allocator>::extract_signed_long_long() const
1641 {
1642    // Extracts a signed long long from *this.
1643    // If (x > maximum of long long) or (x < minimum of long long),
1644    // then the maximum or minimum of long long is returned accordingly.
1645 
1646    if (exp < static_cast<ExponentType>(0))
1647    {
1648       return static_cast<boost::long_long_type>(0);
1649    }
1650 
1651    const bool b_neg = isneg();
1652 
1653    boost::ulong_long_type val;
1654 
1655    if ((!b_neg) && (compare(long_long_max()) > 0))
1656    {
1657       return (std::numeric_limits<boost::long_long_type>::max)();
1658    }
1659    else if (b_neg && (compare(long_long_min()) < 0))
1660    {
1661       return (std::numeric_limits<boost::long_long_type>::min)();
1662    }
1663    else
1664    {
1665       // Extract the data into an boost::ulong_long_type value.
1666       cpp_dec_float<Digits10, ExponentType, Allocator> xn(extract_integer_part());
1667       if (xn.isneg())
1668          xn.negate();
1669 
1670       val = static_cast<boost::ulong_long_type>(xn.data[0]);
1671 
1672       const boost::int32_t imax = (std::min)(static_cast<boost::int32_t>(static_cast<boost::int32_t>(xn.exp) / cpp_dec_float_elem_digits10), static_cast<boost::int32_t>(cpp_dec_float_elem_number - static_cast<boost::int32_t>(1)));
1673 
1674       for (boost::int32_t i = static_cast<boost::int32_t>(1); i <= imax; i++)
1675       {
1676          val *= static_cast<boost::ulong_long_type>(cpp_dec_float_elem_mask);
1677          val += static_cast<boost::ulong_long_type>(xn.data[i]);
1678       }
1679    }
1680 
1681    if (!b_neg)
1682    {
1683       return static_cast<boost::long_long_type>(val);
1684    }
1685    else
1686    {
1687       // This strange expression avoids a hardware trap in the corner case
1688       // that val is the most negative value permitted in boost::long_long_type.
1689       // See https://svn.boost.org/trac/boost/ticket/9740.
1690       //
1691       boost::long_long_type sval = static_cast<boost::long_long_type>(val - 1);
1692       sval                       = -sval;
1693       --sval;
1694       return sval;
1695    }
1696 }
1697 
1698 template <unsigned Digits10, class ExponentType, class Allocator>
extract_unsigned_long_long() const1699 boost::ulong_long_type cpp_dec_float<Digits10, ExponentType, Allocator>::extract_unsigned_long_long() const
1700 {
1701    // Extracts an boost::ulong_long_type from *this.
1702    // If x exceeds the maximum of boost::ulong_long_type,
1703    // then the maximum of boost::ulong_long_type is returned.
1704    // If x is negative, then the boost::ulong_long_type cast of
1705    // the long long extracted value is returned.
1706 
1707    if (isneg())
1708    {
1709       return static_cast<boost::ulong_long_type>(extract_signed_long_long());
1710    }
1711 
1712    if (exp < static_cast<ExponentType>(0))
1713    {
1714       return static_cast<boost::ulong_long_type>(0u);
1715    }
1716 
1717    const cpp_dec_float<Digits10, ExponentType, Allocator> xn(extract_integer_part());
1718 
1719    boost::ulong_long_type val;
1720 
1721    if (xn.compare(ulong_long_max()) > 0)
1722    {
1723       return (std::numeric_limits<boost::ulong_long_type>::max)();
1724    }
1725    else
1726    {
1727       // Extract the data into an boost::ulong_long_type value.
1728       val = static_cast<boost::ulong_long_type>(xn.data[0]);
1729 
1730       const boost::int32_t imax = (std::min)(static_cast<boost::int32_t>(static_cast<boost::int32_t>(xn.exp) / cpp_dec_float_elem_digits10), static_cast<boost::int32_t>(cpp_dec_float_elem_number - static_cast<boost::int32_t>(1)));
1731 
1732       for (boost::int32_t i = static_cast<boost::int32_t>(1); i <= imax; i++)
1733       {
1734          val *= static_cast<boost::ulong_long_type>(cpp_dec_float_elem_mask);
1735          val += static_cast<boost::ulong_long_type>(xn.data[i]);
1736       }
1737    }
1738 
1739    return val;
1740 }
1741 
1742 template <unsigned Digits10, class ExponentType, class Allocator>
extract_integer_part() const1743 cpp_dec_float<Digits10, ExponentType, Allocator> cpp_dec_float<Digits10, ExponentType, Allocator>::extract_integer_part() const
1744 {
1745    // Compute the signed integer part of x.
1746 
1747    if (!(isfinite)())
1748    {
1749       return *this;
1750    }
1751 
1752    if (exp < static_cast<ExponentType>(0))
1753    {
1754       // The absolute value of the number is smaller than 1.
1755       // Thus the integer part is zero.
1756       return zero();
1757    }
1758 
1759    // Truncate the digits from the decimal part, including guard digits
1760    // that do not belong to the integer part.
1761 
1762    // Make a local copy.
1763    cpp_dec_float<Digits10, ExponentType, Allocator> x = *this;
1764 
1765    // Clear out the decimal portion
1766    const size_t first_clear = (static_cast<size_t>(x.exp) / static_cast<size_t>(cpp_dec_float_elem_digits10)) + 1u;
1767    const size_t last_clear  = static_cast<size_t>(cpp_dec_float_elem_number);
1768 
1769    if (first_clear < last_clear)
1770       std::fill(x.data.begin() + first_clear, x.data.begin() + last_clear, static_cast<boost::uint32_t>(0u));
1771 
1772    return x;
1773 }
1774 
1775 template <unsigned Digits10, class ExponentType, class Allocator>
str(boost::intmax_t number_of_digits,std::ios_base::fmtflags f) const1776 std::string cpp_dec_float<Digits10, ExponentType, Allocator>::str(boost::intmax_t number_of_digits, std::ios_base::fmtflags f) const
1777 {
1778    if ((this->isinf)())
1779    {
1780       if (this->isneg())
1781          return "-inf";
1782       else if (f & std::ios_base::showpos)
1783          return "+inf";
1784       else
1785          return "inf";
1786    }
1787    else if ((this->isnan)())
1788    {
1789       return "nan";
1790    }
1791 
1792    std::string     str;
1793    boost::intmax_t org_digits(number_of_digits);
1794    ExponentType    my_exp = order();
1795 
1796    if (number_of_digits == 0)
1797       number_of_digits = cpp_dec_float_total_digits10;
1798 
1799    if (f & std::ios_base::fixed)
1800    {
1801       number_of_digits += my_exp + 1;
1802    }
1803    else if (f & std::ios_base::scientific)
1804       ++number_of_digits;
1805    // Determine the number of elements needed to provide the requested digits from cpp_dec_float<Digits10, ExponentType, Allocator>.
1806    const std::size_t number_of_elements = (std::min)(static_cast<std::size_t>((number_of_digits / static_cast<std::size_t>(cpp_dec_float_elem_digits10)) + 2u),
1807                                                      static_cast<std::size_t>(cpp_dec_float_elem_number));
1808 
1809    // Extract the remaining digits from cpp_dec_float<Digits10, ExponentType, Allocator> after the decimal point.
1810    std::stringstream ss;
1811    ss.imbue(std::locale::classic());
1812    ss << data[0];
1813    // Extract all of the digits from cpp_dec_float<Digits10, ExponentType, Allocator>, beginning with the first data element.
1814    for (std::size_t i = static_cast<std::size_t>(1u); i < number_of_elements; i++)
1815    {
1816       ss << std::setw(static_cast<std::streamsize>(cpp_dec_float_elem_digits10))
1817          << std::setfill(static_cast<char>('0'))
1818          << data[i];
1819    }
1820    str += ss.str();
1821 
1822    bool have_leading_zeros = false;
1823 
1824    if (number_of_digits == 0)
1825    {
1826       // We only get here if the output format is "fixed" and we just need to
1827       // round the first non-zero digit.
1828       number_of_digits -= my_exp + 1; // reset to original value
1829       str.insert(static_cast<std::string::size_type>(0), std::string::size_type(number_of_digits), '0');
1830       have_leading_zeros = true;
1831    }
1832 
1833    if (number_of_digits < 0)
1834    {
1835       str = "0";
1836       if (isneg())
1837          str.insert(static_cast<std::string::size_type>(0), 1, '-');
1838       boost::multiprecision::detail::format_float_string(str, 0, number_of_digits - my_exp - 1, f, this->iszero());
1839       return str;
1840    }
1841    else
1842    {
1843       // Cut the output to the size of the precision.
1844       if (str.length() > static_cast<std::string::size_type>(number_of_digits))
1845       {
1846          // Get the digit after the last needed digit for rounding
1847          const boost::uint32_t round = static_cast<boost::uint32_t>(static_cast<boost::uint32_t>(str[static_cast<std::string::size_type>(number_of_digits)]) - static_cast<boost::uint32_t>('0'));
1848 
1849          bool need_round_up = round >= 5u;
1850 
1851          if (round == 5u)
1852          {
1853             const boost::uint32_t ix = static_cast<boost::uint32_t>(static_cast<boost::uint32_t>(str[static_cast<std::string::size_type>(number_of_digits - 1)]) - static_cast<boost::uint32_t>('0'));
1854             if ((ix & 1u) == 0)
1855             {
1856                // We have an even digit followed by a 5, so we might not actually need to round up
1857                // if all the remaining digits are zero:
1858                if (str.find_first_not_of('0', static_cast<std::string::size_type>(number_of_digits + 1)) == std::string::npos)
1859                {
1860                   bool all_zeros = true;
1861                   // No none-zero trailing digits in the string, now check whatever parts we didn't convert to the string:
1862                   for (std::size_t i = number_of_elements; i < data.size(); i++)
1863                   {
1864                      if (data[i])
1865                      {
1866                         all_zeros = false;
1867                         break;
1868                      }
1869                   }
1870                   if (all_zeros)
1871                      need_round_up = false; // tie break - round to even.
1872                }
1873             }
1874          }
1875 
1876          // Truncate the string
1877          str.erase(static_cast<std::string::size_type>(number_of_digits));
1878 
1879          if (need_round_up)
1880          {
1881             std::size_t ix = static_cast<std::size_t>(str.length() - 1u);
1882 
1883             // Every trailing 9 must be rounded up
1884             while (ix && (static_cast<boost::int32_t>(str.at(ix)) - static_cast<boost::int32_t>('0') == static_cast<boost::int32_t>(9)))
1885             {
1886                str.at(ix) = static_cast<char>('0');
1887                --ix;
1888             }
1889 
1890             if (!ix)
1891             {
1892                // There were nothing but trailing nines.
1893                if (static_cast<boost::int32_t>(static_cast<boost::int32_t>(str.at(ix)) - static_cast<boost::int32_t>(0x30)) == static_cast<boost::int32_t>(9))
1894                {
1895                   // Increment up to the next order and adjust exponent.
1896                   str.at(ix) = static_cast<char>('1');
1897                   ++my_exp;
1898                }
1899                else
1900                {
1901                   // Round up this digit.
1902                   ++str.at(ix);
1903                }
1904             }
1905             else
1906             {
1907                // Round up the last digit.
1908                ++str[ix];
1909             }
1910          }
1911       }
1912    }
1913 
1914    if (have_leading_zeros)
1915    {
1916       // We need to take the zeros back out again, and correct the exponent
1917       // if we rounded up:
1918       if (str[std::string::size_type(number_of_digits - 1)] != '0')
1919       {
1920          ++my_exp;
1921          str.erase(0, std::string::size_type(number_of_digits - 1));
1922       }
1923       else
1924          str.erase(0, std::string::size_type(number_of_digits));
1925    }
1926 
1927    if (isneg())
1928       str.insert(static_cast<std::string::size_type>(0), 1, '-');
1929 
1930    boost::multiprecision::detail::format_float_string(str, my_exp, org_digits, f, this->iszero());
1931    return str;
1932 }
1933 
1934 template <unsigned Digits10, class ExponentType, class Allocator>
rd_string(const char * const s)1935 bool cpp_dec_float<Digits10, ExponentType, Allocator>::rd_string(const char* const s)
1936 {
1937 #ifndef BOOST_NO_EXCEPTIONS
1938    try
1939    {
1940 #endif
1941 
1942       std::string str(s);
1943 
1944       // TBD: Using several regular expressions may significantly reduce
1945       // the code complexity (and perhaps the run-time) of rd_string().
1946 
1947       // Get a possible exponent and remove it.
1948       exp = static_cast<ExponentType>(0);
1949 
1950       std::size_t pos;
1951 
1952       if (((pos = str.find('e')) != std::string::npos) || ((pos = str.find('E')) != std::string::npos))
1953       {
1954          // Remove the exponent part from the string.
1955          exp = boost::lexical_cast<ExponentType>(static_cast<const char*>(str.c_str() + (pos + 1u)));
1956          str = str.substr(static_cast<std::size_t>(0u), pos);
1957       }
1958 
1959       // Get a possible +/- sign and remove it.
1960       neg = false;
1961 
1962       if (str.size())
1963       {
1964          if (str[0] == '-')
1965          {
1966             neg = true;
1967             str.erase(0, 1);
1968          }
1969          else if (str[0] == '+')
1970          {
1971             str.erase(0, 1);
1972          }
1973       }
1974       //
1975       // Special cases for infinities and NaN's:
1976       //
1977       if ((str == "inf") || (str == "INF") || (str == "infinity") || (str == "INFINITY"))
1978       {
1979          if (neg)
1980          {
1981             *this = this->inf();
1982             this->negate();
1983          }
1984          else
1985             *this = this->inf();
1986          return true;
1987       }
1988       if ((str.size() >= 3) && ((str.substr(0, 3) == "nan") || (str.substr(0, 3) == "NAN") || (str.substr(0, 3) == "NaN")))
1989       {
1990          *this = this->nan();
1991          return true;
1992       }
1993 
1994       // Remove the leading zeros for all input types.
1995       const std::string::iterator fwd_it_leading_zero = std::find_if(str.begin(), str.end(), char_is_nonzero_predicate);
1996 
1997       if (fwd_it_leading_zero != str.begin())
1998       {
1999          if (fwd_it_leading_zero == str.end())
2000          {
2001             // The string contains nothing but leading zeros.
2002             // This string represents zero.
2003             operator=(zero());
2004             return true;
2005          }
2006          else
2007          {
2008             str.erase(str.begin(), fwd_it_leading_zero);
2009          }
2010       }
2011 
2012       // Put the input string into the standard cpp_dec_float<Digits10, ExponentType, Allocator> input form
2013       // aaa.bbbbE+/-n, where aaa has 1...cpp_dec_float_elem_digits10, bbbb has an
2014       // even multiple of cpp_dec_float_elem_digits10 which are possibly zero padded
2015       // on the right-end, and n is a signed 64-bit integer which is an
2016       // even multiple of cpp_dec_float_elem_digits10.
2017 
2018       // Find a possible decimal point.
2019       pos = str.find(static_cast<char>('.'));
2020 
2021       if (pos != std::string::npos)
2022       {
2023          // Remove all trailing insignificant zeros.
2024          const std::string::const_reverse_iterator rit_non_zero = std::find_if(str.rbegin(), str.rend(), char_is_nonzero_predicate);
2025 
2026          if (rit_non_zero != static_cast<std::string::const_reverse_iterator>(str.rbegin()))
2027          {
2028             const std::string::size_type ofs = str.length() - std::distance<std::string::const_reverse_iterator>(str.rbegin(), rit_non_zero);
2029             str.erase(str.begin() + ofs, str.end());
2030          }
2031 
2032          // Check if the input is identically zero.
2033          if (str == std::string("."))
2034          {
2035             operator=(zero());
2036             return true;
2037          }
2038 
2039          // Remove leading significant zeros just after the decimal point
2040          // and adjust the exponent accordingly.
2041          // Note that the while-loop operates only on strings of the form ".000abcd..."
2042          // and peels away the zeros just after the decimal point.
2043          if (str.at(static_cast<std::size_t>(0u)) == static_cast<char>('.'))
2044          {
2045             const std::string::iterator it_non_zero = std::find_if(str.begin() + 1u, str.end(), char_is_nonzero_predicate);
2046 
2047             std::size_t delta_exp = static_cast<std::size_t>(0u);
2048 
2049             if (str.at(static_cast<std::size_t>(1u)) == static_cast<char>('0'))
2050             {
2051                delta_exp = std::distance<std::string::const_iterator>(str.begin() + 1u, it_non_zero);
2052             }
2053 
2054             // Bring one single digit into the mantissa and adjust the exponent accordingly.
2055             str.erase(str.begin(), it_non_zero);
2056             str.insert(static_cast<std::string::size_type>(1u), ".");
2057             exp -= static_cast<ExponentType>(delta_exp + 1u);
2058          }
2059       }
2060       else
2061       {
2062          // Input string has no decimal point: Append decimal point.
2063          str.append(".");
2064       }
2065 
2066       // Shift the decimal point such that the exponent is an even multiple of cpp_dec_float_elem_digits10.
2067       std::size_t       n_shift   = static_cast<std::size_t>(0u);
2068       const std::size_t n_exp_rem = static_cast<std::size_t>(exp % static_cast<ExponentType>(cpp_dec_float_elem_digits10));
2069 
2070       if ((exp % static_cast<ExponentType>(cpp_dec_float_elem_digits10)) != static_cast<ExponentType>(0))
2071       {
2072          n_shift = ((exp < static_cast<ExponentType>(0))
2073                         ? static_cast<std::size_t>(n_exp_rem + static_cast<std::size_t>(cpp_dec_float_elem_digits10))
2074                         : static_cast<std::size_t>(n_exp_rem));
2075       }
2076 
2077       // Make sure that there are enough digits for the decimal point shift.
2078       pos = str.find(static_cast<char>('.'));
2079 
2080       std::size_t pos_plus_one = static_cast<std::size_t>(pos + 1u);
2081 
2082       if ((str.length() - pos_plus_one) < n_shift)
2083       {
2084          const std::size_t sz = static_cast<std::size_t>(n_shift - (str.length() - pos_plus_one));
2085 
2086          str.append(std::string(sz, static_cast<char>('0')));
2087       }
2088 
2089       // Do the decimal point shift.
2090       if (n_shift != static_cast<std::size_t>(0u))
2091       {
2092          str.insert(static_cast<std::string::size_type>(pos_plus_one + n_shift), ".");
2093 
2094          str.erase(pos, static_cast<std::string::size_type>(1u));
2095 
2096          exp -= static_cast<ExponentType>(n_shift);
2097       }
2098 
2099       // Cut the size of the mantissa to <= cpp_dec_float_elem_digits10.
2100       pos          = str.find(static_cast<char>('.'));
2101       pos_plus_one = static_cast<std::size_t>(pos + 1u);
2102 
2103       if (pos > static_cast<std::size_t>(cpp_dec_float_elem_digits10))
2104       {
2105          const boost::int32_t n_pos         = static_cast<boost::int32_t>(pos);
2106          const boost::int32_t n_rem_is_zero = ((static_cast<boost::int32_t>(n_pos % cpp_dec_float_elem_digits10) == static_cast<boost::int32_t>(0)) ? static_cast<boost::int32_t>(1) : static_cast<boost::int32_t>(0));
2107          const boost::int32_t n             = static_cast<boost::int32_t>(static_cast<boost::int32_t>(n_pos / cpp_dec_float_elem_digits10) - n_rem_is_zero);
2108 
2109          str.insert(static_cast<std::size_t>(static_cast<boost::int32_t>(n_pos - static_cast<boost::int32_t>(n * cpp_dec_float_elem_digits10))), ".");
2110 
2111          str.erase(pos_plus_one, static_cast<std::size_t>(1u));
2112 
2113          exp += static_cast<ExponentType>(static_cast<ExponentType>(n) * static_cast<ExponentType>(cpp_dec_float_elem_digits10));
2114       }
2115 
2116       // Pad the decimal part such that its value is an even
2117       // multiple of cpp_dec_float_elem_digits10.
2118       pos          = str.find(static_cast<char>('.'));
2119       pos_plus_one = static_cast<std::size_t>(pos + 1u);
2120 
2121       const boost::int32_t n_dec = static_cast<boost::int32_t>(static_cast<boost::int32_t>(str.length() - 1u) - static_cast<boost::int32_t>(pos));
2122       const boost::int32_t n_rem = static_cast<boost::int32_t>(n_dec % cpp_dec_float_elem_digits10);
2123 
2124       boost::int32_t n_cnt = ((n_rem != static_cast<boost::int32_t>(0))
2125                                   ? static_cast<boost::int32_t>(cpp_dec_float_elem_digits10 - n_rem)
2126                                   : static_cast<boost::int32_t>(0));
2127 
2128       if (n_cnt != static_cast<boost::int32_t>(0))
2129       {
2130          str.append(static_cast<std::size_t>(n_cnt), static_cast<char>('0'));
2131       }
2132 
2133       // Truncate decimal part if it is too long.
2134       const std::size_t max_dec = static_cast<std::size_t>((cpp_dec_float_elem_number - 1) * cpp_dec_float_elem_digits10);
2135 
2136       if (static_cast<std::size_t>(str.length() - pos) > max_dec)
2137       {
2138          str = str.substr(static_cast<std::size_t>(0u),
2139                           static_cast<std::size_t>(pos_plus_one + max_dec));
2140       }
2141 
2142       // Now the input string has the standard cpp_dec_float<Digits10, ExponentType, Allocator> input form.
2143       // (See the comment above.)
2144 
2145       // Set all the data elements to 0.
2146       std::fill(data.begin(), data.end(), static_cast<boost::uint32_t>(0u));
2147 
2148       // Extract the data.
2149 
2150       // First get the digits to the left of the decimal point...
2151       data[0u] = boost::lexical_cast<boost::uint32_t>(str.substr(static_cast<std::size_t>(0u), pos));
2152 
2153       // ...then get the remaining digits to the right of the decimal point.
2154       const std::string::size_type i_end = ((str.length() - pos_plus_one) / static_cast<std::string::size_type>(cpp_dec_float_elem_digits10));
2155 
2156       for (std::string::size_type i = static_cast<std::string::size_type>(0u); i < i_end; i++)
2157       {
2158          const std::string::const_iterator it = str.begin() + pos_plus_one + (i * static_cast<std::string::size_type>(cpp_dec_float_elem_digits10));
2159 
2160          data[i + 1u] = boost::lexical_cast<boost::uint32_t>(std::string(it, it + static_cast<std::string::size_type>(cpp_dec_float_elem_digits10)));
2161       }
2162 
2163       // Check for overflow...
2164       if (exp > cpp_dec_float_max_exp10)
2165       {
2166          const bool b_result_is_neg = neg;
2167 
2168          *this = inf();
2169          if (b_result_is_neg)
2170             negate();
2171       }
2172 
2173       // ...and check for underflow.
2174       if (exp <= cpp_dec_float_min_exp10)
2175       {
2176          if (exp == cpp_dec_float_min_exp10)
2177          {
2178             // Check for identity with the minimum value.
2179             cpp_dec_float<Digits10, ExponentType, Allocator> test = *this;
2180 
2181             test.exp = static_cast<ExponentType>(0);
2182 
2183             if (test.isone())
2184             {
2185                *this = zero();
2186             }
2187          }
2188          else
2189          {
2190             *this = zero();
2191          }
2192       }
2193 
2194 #ifndef BOOST_NO_EXCEPTIONS
2195    }
2196    catch (const bad_lexical_cast&)
2197    {
2198       // Rethrow with better error message:
2199       std::string msg = "Unable to parse the string \"";
2200       msg += s;
2201       msg += "\" as a floating point value.";
2202       throw std::runtime_error(msg);
2203    }
2204 #endif
2205    return true;
2206 }
2207 
2208 template <unsigned Digits10, class ExponentType, class Allocator>
cpp_dec_float(const double mantissa,const ExponentType exponent)2209 cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float(const double mantissa, const ExponentType exponent)
2210     : data(),
2211       exp(static_cast<ExponentType>(0)),
2212       neg(false),
2213       fpclass(cpp_dec_float_finite),
2214       prec_elem(cpp_dec_float_elem_number)
2215 {
2216    // Create *this cpp_dec_float<Digits10, ExponentType, Allocator> from a given mantissa and exponent.
2217    // Note: This constructor does not maintain the full precision of double.
2218 
2219    const bool mantissa_is_iszero = (::fabs(mantissa) < ((std::numeric_limits<double>::min)() * (1.0 + std::numeric_limits<double>::epsilon())));
2220 
2221    if (mantissa_is_iszero)
2222    {
2223       std::fill(data.begin(), data.end(), static_cast<boost::uint32_t>(0u));
2224       return;
2225    }
2226 
2227    const bool b_neg = (mantissa < 0.0);
2228 
2229    double       d = ((!b_neg) ? mantissa : -mantissa);
2230    ExponentType e = exponent;
2231 
2232    while (d > 10.0)
2233    {
2234       d /= 10.0;
2235       ++e;
2236    }
2237    while (d < 1.0)
2238    {
2239       d *= 10.0;
2240       --e;
2241    }
2242 
2243    boost::int32_t shift = static_cast<boost::int32_t>(e % static_cast<boost::int32_t>(cpp_dec_float_elem_digits10));
2244 
2245    while (static_cast<boost::int32_t>(shift-- % cpp_dec_float_elem_digits10) != static_cast<boost::int32_t>(0))
2246    {
2247       d *= 10.0;
2248       --e;
2249    }
2250 
2251    exp = e;
2252    neg = b_neg;
2253 
2254    std::fill(data.begin(), data.end(), static_cast<boost::uint32_t>(0u));
2255 
2256    static const boost::int32_t digit_ratio = static_cast<boost::int32_t>(static_cast<boost::int32_t>(std::numeric_limits<double>::digits10) / static_cast<boost::int32_t>(cpp_dec_float_elem_digits10));
2257    static const boost::int32_t digit_loops = static_cast<boost::int32_t>(digit_ratio + static_cast<boost::int32_t>(2));
2258 
2259    for (boost::int32_t i = static_cast<boost::int32_t>(0); i < digit_loops; i++)
2260    {
2261       boost::uint32_t n = static_cast<boost::uint32_t>(static_cast<boost::uint64_t>(d));
2262       data[i]           = static_cast<boost::uint32_t>(n);
2263       d -= static_cast<double>(n);
2264       d *= static_cast<double>(cpp_dec_float_elem_mask);
2265    }
2266 }
2267 
2268 template <unsigned Digits10, class ExponentType, class Allocator>
2269 template <class Float>
operator =(Float a)2270 typename boost::enable_if_c<boost::is_floating_point<Float>::value, cpp_dec_float<Digits10, ExponentType, Allocator>&>::type cpp_dec_float<Digits10, ExponentType, Allocator>::operator=(Float a)
2271 {
2272    // Christopher Kormanyos's original code used a cast to boost::long_long_type here, but that fails
2273    // when long double has more digits than a boost::long_long_type.
2274    using std::floor;
2275    using std::frexp;
2276    using std::ldexp;
2277 
2278    if (a == 0)
2279       return *this = zero();
2280 
2281    if (a == 1)
2282       return *this = one();
2283 
2284    if ((boost::math::isinf)(a))
2285    {
2286       *this = inf();
2287       if (a < 0)
2288          this->negate();
2289       return *this;
2290    }
2291 
2292    if ((boost::math::isnan)(a))
2293       return *this = nan();
2294 
2295    int         e;
2296    Float f, term;
2297    *this = zero();
2298 
2299    f = frexp(a, &e);
2300    // See https://svn.boost.org/trac/boost/ticket/10924 for an example of why this may go wrong:
2301    BOOST_ASSERT((boost::math::isfinite)(f));
2302 
2303    static const int shift = std::numeric_limits<int>::digits - 1;
2304 
2305    while (f)
2306    {
2307       // extract int sized bits from f:
2308       f = ldexp(f, shift);
2309       BOOST_ASSERT((boost::math::isfinite)(f));
2310       term = floor(f);
2311       e -= shift;
2312       *this *= pow2(shift);
2313       if (term > 0)
2314          add_unsigned_long_long(static_cast<unsigned>(term));
2315       else
2316          sub_unsigned_long_long(static_cast<unsigned>(-term));
2317       f -= term;
2318    }
2319 
2320    if (e != 0)
2321       *this *= pow2(e);
2322 
2323    return *this;
2324 }
2325 
2326 template <unsigned Digits10, class ExponentType, class Allocator>
from_unsigned_long_long(const boost::ulong_long_type u)2327 void cpp_dec_float<Digits10, ExponentType, Allocator>::from_unsigned_long_long(const boost::ulong_long_type u)
2328 {
2329    std::fill(data.begin(), data.end(), static_cast<boost::uint32_t>(0u));
2330 
2331    exp       = static_cast<ExponentType>(0);
2332    neg       = false;
2333    fpclass   = cpp_dec_float_finite;
2334    prec_elem = cpp_dec_float_elem_number;
2335 
2336    if (u == 0)
2337    {
2338       return;
2339    }
2340 
2341    std::size_t i = static_cast<std::size_t>(0u);
2342 
2343    boost::ulong_long_type uu = u;
2344 
2345    boost::uint32_t temp[(std::numeric_limits<boost::ulong_long_type>::digits10 / static_cast<int>(cpp_dec_float_elem_digits10)) + 3] = {static_cast<boost::uint32_t>(0u)};
2346 
2347    while (uu != static_cast<boost::ulong_long_type>(0u))
2348    {
2349       temp[i] = static_cast<boost::uint32_t>(uu % static_cast<boost::ulong_long_type>(cpp_dec_float_elem_mask));
2350       uu      = static_cast<boost::ulong_long_type>(uu / static_cast<boost::ulong_long_type>(cpp_dec_float_elem_mask));
2351       ++i;
2352    }
2353 
2354    if (i > static_cast<std::size_t>(1u))
2355    {
2356       exp += static_cast<ExponentType>((i - 1u) * static_cast<std::size_t>(cpp_dec_float_elem_digits10));
2357    }
2358 
2359    std::reverse(temp, temp + i);
2360    std::copy(temp, temp + (std::min)(i, static_cast<std::size_t>(cpp_dec_float_elem_number)), data.begin());
2361 }
2362 
2363 template <unsigned Digits10, class ExponentType, class Allocator>
mul_loop_uv(boost::uint32_t * const u,const boost::uint32_t * const v,const boost::int32_t p)2364 boost::uint32_t cpp_dec_float<Digits10, ExponentType, Allocator>::mul_loop_uv(boost::uint32_t* const u, const boost::uint32_t* const v, const boost::int32_t p)
2365 {
2366    //
2367    // There is a limit on how many limbs this algorithm can handle without dropping digits
2368    // due to overflow in the carry, it is:
2369    //
2370    // FLOOR( (2^64 - 1) / (10^8 * 10^8) ) == 1844
2371    //
2372    BOOST_STATIC_ASSERT_MSG(cpp_dec_float_elem_number < 1800, "Too many limbs in the data type for the multiplication algorithm - unsupported precision in cpp_dec_float.");
2373 
2374    boost::uint64_t carry = static_cast<boost::uint64_t>(0u);
2375 
2376    for (boost::int32_t j = static_cast<boost::int32_t>(p - 1u); j >= static_cast<boost::int32_t>(0); j--)
2377    {
2378       boost::uint64_t sum = carry;
2379 
2380       for (boost::int32_t i = j; i >= static_cast<boost::int32_t>(0); i--)
2381       {
2382          sum += static_cast<boost::uint64_t>(u[j - i] * static_cast<boost::uint64_t>(v[i]));
2383       }
2384 
2385       u[j]  = static_cast<boost::uint32_t>(sum % static_cast<boost::uint32_t>(cpp_dec_float_elem_mask));
2386       carry = static_cast<boost::uint64_t>(sum / static_cast<boost::uint32_t>(cpp_dec_float_elem_mask));
2387    }
2388 
2389    return static_cast<boost::uint32_t>(carry);
2390 }
2391 
2392 template <unsigned Digits10, class ExponentType, class Allocator>
mul_loop_n(boost::uint32_t * const u,boost::uint32_t n,const boost::int32_t p)2393 boost::uint32_t cpp_dec_float<Digits10, ExponentType, Allocator>::mul_loop_n(boost::uint32_t* const u, boost::uint32_t n, const boost::int32_t p)
2394 {
2395    boost::uint64_t carry = static_cast<boost::uint64_t>(0u);
2396 
2397    // Multiplication loop.
2398    for (boost::int32_t j = p - 1; j >= static_cast<boost::int32_t>(0); j--)
2399    {
2400       const boost::uint64_t t = static_cast<boost::uint64_t>(carry + static_cast<boost::uint64_t>(u[j] * static_cast<boost::uint64_t>(n)));
2401       carry                   = static_cast<boost::uint64_t>(t / static_cast<boost::uint32_t>(cpp_dec_float_elem_mask));
2402       u[j]                    = static_cast<boost::uint32_t>(t - static_cast<boost::uint64_t>(static_cast<boost::uint32_t>(cpp_dec_float_elem_mask) * static_cast<boost::uint64_t>(carry)));
2403    }
2404 
2405    return static_cast<boost::uint32_t>(carry);
2406 }
2407 
2408 template <unsigned Digits10, class ExponentType, class Allocator>
div_loop_n(boost::uint32_t * const u,boost::uint32_t n,const boost::int32_t p)2409 boost::uint32_t cpp_dec_float<Digits10, ExponentType, Allocator>::div_loop_n(boost::uint32_t* const u, boost::uint32_t n, const boost::int32_t p)
2410 {
2411    boost::uint64_t prev = static_cast<boost::uint64_t>(0u);
2412 
2413    for (boost::int32_t j = static_cast<boost::int32_t>(0); j < p; j++)
2414    {
2415       const boost::uint64_t t = static_cast<boost::uint64_t>(u[j] + static_cast<boost::uint64_t>(prev * static_cast<boost::uint32_t>(cpp_dec_float_elem_mask)));
2416       u[j]                    = static_cast<boost::uint32_t>(t / n);
2417       prev                    = static_cast<boost::uint64_t>(t - static_cast<boost::uint64_t>(n * static_cast<boost::uint64_t>(u[j])));
2418    }
2419 
2420    return static_cast<boost::uint32_t>(prev);
2421 }
2422 
2423 template <unsigned Digits10, class ExponentType, class Allocator>
pow2(const boost::long_long_type p)2424 cpp_dec_float<Digits10, ExponentType, Allocator> cpp_dec_float<Digits10, ExponentType, Allocator>::pow2(const boost::long_long_type p)
2425 {
2426    // Create a static const table of p^2 for -128 < p < +128.
2427    // Note: The size of this table must be odd-numbered and
2428    // symmetric about 0.
2429    init.do_nothing();
2430    static const boost::array<cpp_dec_float<Digits10, ExponentType, Allocator>, 255u> p2_data =
2431        {{cpp_dec_float("5.877471754111437539843682686111228389093327783860437607543758531392086297273635864257812500000000000e-39"),
2432          cpp_dec_float("1.175494350822287507968736537222245677818665556772087521508751706278417259454727172851562500000000000e-38"),
2433          cpp_dec_float("2.350988701644575015937473074444491355637331113544175043017503412556834518909454345703125000000000000e-38"),
2434          cpp_dec_float("4.701977403289150031874946148888982711274662227088350086035006825113669037818908691406250000000000000e-38"),
2435          cpp_dec_float("9.403954806578300063749892297777965422549324454176700172070013650227338075637817382812500000000000000e-38"),
2436          cpp_dec_float("1.880790961315660012749978459555593084509864890835340034414002730045467615127563476562500000000000000e-37"),
2437          cpp_dec_float("3.761581922631320025499956919111186169019729781670680068828005460090935230255126953125000000000000000e-37"),
2438          cpp_dec_float("7.523163845262640050999913838222372338039459563341360137656010920181870460510253906250000000000000000e-37"),
2439          cpp_dec_float("1.504632769052528010199982767644474467607891912668272027531202184036374092102050781250000000000000000e-36"),
2440          cpp_dec_float("3.009265538105056020399965535288948935215783825336544055062404368072748184204101562500000000000000000e-36"),
2441          cpp_dec_float("6.018531076210112040799931070577897870431567650673088110124808736145496368408203125000000000000000000e-36"),
2442          cpp_dec_float("1.203706215242022408159986214115579574086313530134617622024961747229099273681640625000000000000000000e-35"),
2443          cpp_dec_float("2.407412430484044816319972428231159148172627060269235244049923494458198547363281250000000000000000000e-35"),
2444          cpp_dec_float("4.814824860968089632639944856462318296345254120538470488099846988916397094726562500000000000000000000e-35"),
2445          cpp_dec_float("9.629649721936179265279889712924636592690508241076940976199693977832794189453125000000000000000000000e-35"),
2446          cpp_dec_float("1.925929944387235853055977942584927318538101648215388195239938795566558837890625000000000000000000000e-34"),
2447          cpp_dec_float("3.851859888774471706111955885169854637076203296430776390479877591133117675781250000000000000000000000e-34"),
2448          cpp_dec_float("7.703719777548943412223911770339709274152406592861552780959755182266235351562500000000000000000000000e-34"),
2449          cpp_dec_float("1.540743955509788682444782354067941854830481318572310556191951036453247070312500000000000000000000000e-33"),
2450          cpp_dec_float("3.081487911019577364889564708135883709660962637144621112383902072906494140625000000000000000000000000e-33"),
2451          cpp_dec_float("6.162975822039154729779129416271767419321925274289242224767804145812988281250000000000000000000000000e-33"),
2452          cpp_dec_float("1.232595164407830945955825883254353483864385054857848444953560829162597656250000000000000000000000000e-32"),
2453          cpp_dec_float("2.465190328815661891911651766508706967728770109715696889907121658325195312500000000000000000000000000e-32"),
2454          cpp_dec_float("4.930380657631323783823303533017413935457540219431393779814243316650390625000000000000000000000000000e-32"),
2455          cpp_dec_float("9.860761315262647567646607066034827870915080438862787559628486633300781250000000000000000000000000000e-32"),
2456          cpp_dec_float("1.972152263052529513529321413206965574183016087772557511925697326660156250000000000000000000000000000e-31"),
2457          cpp_dec_float("3.944304526105059027058642826413931148366032175545115023851394653320312500000000000000000000000000000e-31"),
2458          cpp_dec_float("7.888609052210118054117285652827862296732064351090230047702789306640625000000000000000000000000000000e-31"),
2459          cpp_dec_float("1.577721810442023610823457130565572459346412870218046009540557861328125000000000000000000000000000000e-30"),
2460          cpp_dec_float("3.155443620884047221646914261131144918692825740436092019081115722656250000000000000000000000000000000e-30"),
2461          cpp_dec_float("6.310887241768094443293828522262289837385651480872184038162231445312500000000000000000000000000000000e-30"),
2462          cpp_dec_float("1.262177448353618888658765704452457967477130296174436807632446289062500000000000000000000000000000000e-29"),
2463          cpp_dec_float("2.524354896707237777317531408904915934954260592348873615264892578125000000000000000000000000000000000e-29"),
2464          cpp_dec_float("5.048709793414475554635062817809831869908521184697747230529785156250000000000000000000000000000000000e-29"),
2465          cpp_dec_float("1.009741958682895110927012563561966373981704236939549446105957031250000000000000000000000000000000000e-28"),
2466          cpp_dec_float("2.019483917365790221854025127123932747963408473879098892211914062500000000000000000000000000000000000e-28"),
2467          cpp_dec_float("4.038967834731580443708050254247865495926816947758197784423828125000000000000000000000000000000000000e-28"),
2468          cpp_dec_float("8.077935669463160887416100508495730991853633895516395568847656250000000000000000000000000000000000000e-28"),
2469          cpp_dec_float("1.615587133892632177483220101699146198370726779103279113769531250000000000000000000000000000000000000e-27"),
2470          cpp_dec_float("3.231174267785264354966440203398292396741453558206558227539062500000000000000000000000000000000000000e-27"),
2471          cpp_dec_float("6.462348535570528709932880406796584793482907116413116455078125000000000000000000000000000000000000000e-27"),
2472          cpp_dec_float("1.292469707114105741986576081359316958696581423282623291015625000000000000000000000000000000000000000e-26"),
2473          cpp_dec_float("2.584939414228211483973152162718633917393162846565246582031250000000000000000000000000000000000000000e-26"),
2474          cpp_dec_float("5.169878828456422967946304325437267834786325693130493164062500000000000000000000000000000000000000000e-26"),
2475          cpp_dec_float("1.033975765691284593589260865087453566957265138626098632812500000000000000000000000000000000000000000e-25"),
2476          cpp_dec_float("2.067951531382569187178521730174907133914530277252197265625000000000000000000000000000000000000000000e-25"),
2477          cpp_dec_float("4.135903062765138374357043460349814267829060554504394531250000000000000000000000000000000000000000000e-25"),
2478          cpp_dec_float("8.271806125530276748714086920699628535658121109008789062500000000000000000000000000000000000000000000e-25"),
2479          cpp_dec_float("1.654361225106055349742817384139925707131624221801757812500000000000000000000000000000000000000000000e-24"),
2480          cpp_dec_float("3.308722450212110699485634768279851414263248443603515625000000000000000000000000000000000000000000000e-24"),
2481          cpp_dec_float("6.617444900424221398971269536559702828526496887207031250000000000000000000000000000000000000000000000e-24"),
2482          cpp_dec_float("1.323488980084844279794253907311940565705299377441406250000000000000000000000000000000000000000000000e-23"),
2483          cpp_dec_float("2.646977960169688559588507814623881131410598754882812500000000000000000000000000000000000000000000000e-23"),
2484          cpp_dec_float("5.293955920339377119177015629247762262821197509765625000000000000000000000000000000000000000000000000e-23"),
2485          cpp_dec_float("1.058791184067875423835403125849552452564239501953125000000000000000000000000000000000000000000000000e-22"),
2486          cpp_dec_float("2.117582368135750847670806251699104905128479003906250000000000000000000000000000000000000000000000000e-22"),
2487          cpp_dec_float("4.235164736271501695341612503398209810256958007812500000000000000000000000000000000000000000000000000e-22"),
2488          cpp_dec_float("8.470329472543003390683225006796419620513916015625000000000000000000000000000000000000000000000000000e-22"),
2489          cpp_dec_float("1.694065894508600678136645001359283924102783203125000000000000000000000000000000000000000000000000000e-21"),
2490          cpp_dec_float("3.388131789017201356273290002718567848205566406250000000000000000000000000000000000000000000000000000e-21"),
2491          cpp_dec_float("6.776263578034402712546580005437135696411132812500000000000000000000000000000000000000000000000000000e-21"),
2492          cpp_dec_float("1.355252715606880542509316001087427139282226562500000000000000000000000000000000000000000000000000000e-20"),
2493          cpp_dec_float("2.710505431213761085018632002174854278564453125000000000000000000000000000000000000000000000000000000e-20"),
2494          cpp_dec_float("5.421010862427522170037264004349708557128906250000000000000000000000000000000000000000000000000000000e-20"),
2495          cpp_dec_float("1.084202172485504434007452800869941711425781250000000000000000000000000000000000000000000000000000000e-19"),
2496          cpp_dec_float("2.168404344971008868014905601739883422851562500000000000000000000000000000000000000000000000000000000e-19"),
2497          cpp_dec_float("4.336808689942017736029811203479766845703125000000000000000000000000000000000000000000000000000000000e-19"),
2498          cpp_dec_float("8.673617379884035472059622406959533691406250000000000000000000000000000000000000000000000000000000000e-19"),
2499          cpp_dec_float("1.734723475976807094411924481391906738281250000000000000000000000000000000000000000000000000000000000e-18"),
2500          cpp_dec_float("3.469446951953614188823848962783813476562500000000000000000000000000000000000000000000000000000000000e-18"),
2501          cpp_dec_float("6.938893903907228377647697925567626953125000000000000000000000000000000000000000000000000000000000000e-18"),
2502          cpp_dec_float("1.387778780781445675529539585113525390625000000000000000000000000000000000000000000000000000000000000e-17"),
2503          cpp_dec_float("2.775557561562891351059079170227050781250000000000000000000000000000000000000000000000000000000000000e-17"),
2504          cpp_dec_float("5.551115123125782702118158340454101562500000000000000000000000000000000000000000000000000000000000000e-17"),
2505          cpp_dec_float("1.110223024625156540423631668090820312500000000000000000000000000000000000000000000000000000000000000e-16"),
2506          cpp_dec_float("2.220446049250313080847263336181640625000000000000000000000000000000000000000000000000000000000000000e-16"),
2507          cpp_dec_float("4.440892098500626161694526672363281250000000000000000000000000000000000000000000000000000000000000000e-16"),
2508          cpp_dec_float("8.881784197001252323389053344726562500000000000000000000000000000000000000000000000000000000000000000e-16"),
2509          cpp_dec_float("1.776356839400250464677810668945312500000000000000000000000000000000000000000000000000000000000000000e-15"),
2510          cpp_dec_float("3.552713678800500929355621337890625000000000000000000000000000000000000000000000000000000000000000000e-15"),
2511          cpp_dec_float("7.105427357601001858711242675781250000000000000000000000000000000000000000000000000000000000000000000e-15"),
2512          cpp_dec_float("1.421085471520200371742248535156250000000000000000000000000000000000000000000000000000000000000000000e-14"),
2513          cpp_dec_float("2.842170943040400743484497070312500000000000000000000000000000000000000000000000000000000000000000000e-14"),
2514          cpp_dec_float("5.684341886080801486968994140625000000000000000000000000000000000000000000000000000000000000000000000e-14"),
2515          cpp_dec_float("1.136868377216160297393798828125000000000000000000000000000000000000000000000000000000000000000000000e-13"),
2516          cpp_dec_float("2.273736754432320594787597656250000000000000000000000000000000000000000000000000000000000000000000000e-13"),
2517          cpp_dec_float("4.547473508864641189575195312500000000000000000000000000000000000000000000000000000000000000000000000e-13"),
2518          cpp_dec_float("9.094947017729282379150390625000000000000000000000000000000000000000000000000000000000000000000000000e-13"),
2519          cpp_dec_float("1.818989403545856475830078125000000000000000000000000000000000000000000000000000000000000000000000000e-12"),
2520          cpp_dec_float("3.637978807091712951660156250000000000000000000000000000000000000000000000000000000000000000000000000e-12"),
2521          cpp_dec_float("7.275957614183425903320312500000000000000000000000000000000000000000000000000000000000000000000000000e-12"),
2522          cpp_dec_float("1.455191522836685180664062500000000000000000000000000000000000000000000000000000000000000000000000000e-11"),
2523          cpp_dec_float("2.910383045673370361328125000000000000000000000000000000000000000000000000000000000000000000000000000e-11"),
2524          cpp_dec_float("5.820766091346740722656250000000000000000000000000000000000000000000000000000000000000000000000000000e-11"),
2525          cpp_dec_float("1.164153218269348144531250000000000000000000000000000000000000000000000000000000000000000000000000000e-10"),
2526          cpp_dec_float("2.328306436538696289062500000000000000000000000000000000000000000000000000000000000000000000000000000e-10"),
2527          cpp_dec_float("4.656612873077392578125000000000000000000000000000000000000000000000000000000000000000000000000000000e-10"),
2528          cpp_dec_float("9.313225746154785156250000000000000000000000000000000000000000000000000000000000000000000000000000000e-10"),
2529          cpp_dec_float("1.862645149230957031250000000000000000000000000000000000000000000000000000000000000000000000000000000e-9"),
2530          cpp_dec_float("3.725290298461914062500000000000000000000000000000000000000000000000000000000000000000000000000000000e-9"),
2531          cpp_dec_float("7.450580596923828125000000000000000000000000000000000000000000000000000000000000000000000000000000000e-9"),
2532          cpp_dec_float("1.490116119384765625000000000000000000000000000000000000000000000000000000000000000000000000000000000e-8"),
2533          cpp_dec_float("2.980232238769531250000000000000000000000000000000000000000000000000000000000000000000000000000000000e-8"),
2534          cpp_dec_float("5.960464477539062500000000000000000000000000000000000000000000000000000000000000000000000000000000000e-8"),
2535          cpp_dec_float("1.192092895507812500000000000000000000000000000000000000000000000000000000000000000000000000000000000e-7"),
2536          cpp_dec_float("2.384185791015625000000000000000000000000000000000000000000000000000000000000000000000000000000000000e-7"),
2537          cpp_dec_float("4.768371582031250000000000000000000000000000000000000000000000000000000000000000000000000000000000000e-7"),
2538          cpp_dec_float("9.536743164062500000000000000000000000000000000000000000000000000000000000000000000000000000000000000e-7"),
2539          cpp_dec_float("1.907348632812500000000000000000000000000000000000000000000000000000000000000000000000000000000000000e-6"),
2540          cpp_dec_float("3.814697265625000000000000000000000000000000000000000000000000000000000000000000000000000000000000000e-6"),
2541          cpp_dec_float("7.629394531250000000000000000000000000000000000000000000000000000000000000000000000000000000000000000e-6"),
2542          cpp_dec_float("0.000015258789062500000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2543          cpp_dec_float("0.000030517578125000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2544          cpp_dec_float("0.000061035156250000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2545          cpp_dec_float("0.000122070312500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2546          cpp_dec_float("0.000244140625000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2547          cpp_dec_float("0.000488281250000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2548          cpp_dec_float("0.000976562500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2549          cpp_dec_float("0.001953125000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2550          cpp_dec_float("0.003906250000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2551          cpp_dec_float("0.007812500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2552          cpp_dec_float("0.01562500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2553          cpp_dec_float("0.03125000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2554          cpp_dec_float("0.06250000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
2555          cpp_dec_float("0.125"),
2556          cpp_dec_float("0.25"),
2557          cpp_dec_float("0.5"),
2558          one(),
2559          two(),
2560          cpp_dec_float(static_cast<boost::ulong_long_type>(4)),
2561          cpp_dec_float(static_cast<boost::ulong_long_type>(8)),
2562          cpp_dec_float(static_cast<boost::ulong_long_type>(16)),
2563          cpp_dec_float(static_cast<boost::ulong_long_type>(32)),
2564          cpp_dec_float(static_cast<boost::ulong_long_type>(64)),
2565          cpp_dec_float(static_cast<boost::ulong_long_type>(128)),
2566          cpp_dec_float(static_cast<boost::ulong_long_type>(256)),
2567          cpp_dec_float(static_cast<boost::ulong_long_type>(512)),
2568          cpp_dec_float(static_cast<boost::ulong_long_type>(1024)),
2569          cpp_dec_float(static_cast<boost::ulong_long_type>(2048)),
2570          cpp_dec_float(static_cast<boost::ulong_long_type>(4096)),
2571          cpp_dec_float(static_cast<boost::ulong_long_type>(8192)),
2572          cpp_dec_float(static_cast<boost::ulong_long_type>(16384)),
2573          cpp_dec_float(static_cast<boost::ulong_long_type>(32768)),
2574          cpp_dec_float(static_cast<boost::ulong_long_type>(65536)),
2575          cpp_dec_float(static_cast<boost::ulong_long_type>(131072)),
2576          cpp_dec_float(static_cast<boost::ulong_long_type>(262144)),
2577          cpp_dec_float(static_cast<boost::ulong_long_type>(524288)),
2578          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 20u)),
2579          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 21u)),
2580          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 22u)),
2581          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 23u)),
2582          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 24u)),
2583          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 25u)),
2584          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 26u)),
2585          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 27u)),
2586          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 28u)),
2587          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 29u)),
2588          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 30u)),
2589          cpp_dec_float(static_cast<boost::uint64_t>(1uL << 31u)),
2590          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 32u)),
2591          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 33u)),
2592          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 34u)),
2593          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 35u)),
2594          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 36u)),
2595          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 37u)),
2596          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 38u)),
2597          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 39u)),
2598          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 40u)),
2599          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 41u)),
2600          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 42u)),
2601          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 43u)),
2602          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 44u)),
2603          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 45u)),
2604          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 46u)),
2605          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 47u)),
2606          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 48u)),
2607          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 49u)),
2608          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 50u)),
2609          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 51u)),
2610          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 52u)),
2611          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 53u)),
2612          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 54u)),
2613          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 55u)),
2614          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 56u)),
2615          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 57u)),
2616          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 58u)),
2617          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 59u)),
2618          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 60u)),
2619          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 61u)),
2620          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 62u)),
2621          cpp_dec_float(static_cast<boost::uint64_t>(1uLL << 63u)),
2622          cpp_dec_float("1.844674407370955161600000000000000000000000000000000000000000000000000000000000000000000000000000000e19"),
2623          cpp_dec_float("3.689348814741910323200000000000000000000000000000000000000000000000000000000000000000000000000000000e19"),
2624          cpp_dec_float("7.378697629483820646400000000000000000000000000000000000000000000000000000000000000000000000000000000e19"),
2625          cpp_dec_float("1.475739525896764129280000000000000000000000000000000000000000000000000000000000000000000000000000000e20"),
2626          cpp_dec_float("2.951479051793528258560000000000000000000000000000000000000000000000000000000000000000000000000000000e20"),
2627          cpp_dec_float("5.902958103587056517120000000000000000000000000000000000000000000000000000000000000000000000000000000e20"),
2628          cpp_dec_float("1.180591620717411303424000000000000000000000000000000000000000000000000000000000000000000000000000000e21"),
2629          cpp_dec_float("2.361183241434822606848000000000000000000000000000000000000000000000000000000000000000000000000000000e21"),
2630          cpp_dec_float("4.722366482869645213696000000000000000000000000000000000000000000000000000000000000000000000000000000e21"),
2631          cpp_dec_float("9.444732965739290427392000000000000000000000000000000000000000000000000000000000000000000000000000000e21"),
2632          cpp_dec_float("1.888946593147858085478400000000000000000000000000000000000000000000000000000000000000000000000000000e22"),
2633          cpp_dec_float("3.777893186295716170956800000000000000000000000000000000000000000000000000000000000000000000000000000e22"),
2634          cpp_dec_float("7.555786372591432341913600000000000000000000000000000000000000000000000000000000000000000000000000000e22"),
2635          cpp_dec_float("1.511157274518286468382720000000000000000000000000000000000000000000000000000000000000000000000000000e23"),
2636          cpp_dec_float("3.022314549036572936765440000000000000000000000000000000000000000000000000000000000000000000000000000e23"),
2637          cpp_dec_float("6.044629098073145873530880000000000000000000000000000000000000000000000000000000000000000000000000000e23"),
2638          cpp_dec_float("1.208925819614629174706176000000000000000000000000000000000000000000000000000000000000000000000000000e24"),
2639          cpp_dec_float("2.417851639229258349412352000000000000000000000000000000000000000000000000000000000000000000000000000e24"),
2640          cpp_dec_float("4.835703278458516698824704000000000000000000000000000000000000000000000000000000000000000000000000000e24"),
2641          cpp_dec_float("9.671406556917033397649408000000000000000000000000000000000000000000000000000000000000000000000000000e24"),
2642          cpp_dec_float("1.934281311383406679529881600000000000000000000000000000000000000000000000000000000000000000000000000e25"),
2643          cpp_dec_float("3.868562622766813359059763200000000000000000000000000000000000000000000000000000000000000000000000000e25"),
2644          cpp_dec_float("7.737125245533626718119526400000000000000000000000000000000000000000000000000000000000000000000000000e25"),
2645          cpp_dec_float("1.547425049106725343623905280000000000000000000000000000000000000000000000000000000000000000000000000e26"),
2646          cpp_dec_float("3.094850098213450687247810560000000000000000000000000000000000000000000000000000000000000000000000000e26"),
2647          cpp_dec_float("6.189700196426901374495621120000000000000000000000000000000000000000000000000000000000000000000000000e26"),
2648          cpp_dec_float("1.237940039285380274899124224000000000000000000000000000000000000000000000000000000000000000000000000e27"),
2649          cpp_dec_float("2.475880078570760549798248448000000000000000000000000000000000000000000000000000000000000000000000000e27"),
2650          cpp_dec_float("4.951760157141521099596496896000000000000000000000000000000000000000000000000000000000000000000000000e27"),
2651          cpp_dec_float("9.903520314283042199192993792000000000000000000000000000000000000000000000000000000000000000000000000e27"),
2652          cpp_dec_float("1.980704062856608439838598758400000000000000000000000000000000000000000000000000000000000000000000000e28"),
2653          cpp_dec_float("3.961408125713216879677197516800000000000000000000000000000000000000000000000000000000000000000000000e28"),
2654          cpp_dec_float("7.922816251426433759354395033600000000000000000000000000000000000000000000000000000000000000000000000e28"),
2655          cpp_dec_float("1.584563250285286751870879006720000000000000000000000000000000000000000000000000000000000000000000000e29"),
2656          cpp_dec_float("3.169126500570573503741758013440000000000000000000000000000000000000000000000000000000000000000000000e29"),
2657          cpp_dec_float("6.338253001141147007483516026880000000000000000000000000000000000000000000000000000000000000000000000e29"),
2658          cpp_dec_float("1.267650600228229401496703205376000000000000000000000000000000000000000000000000000000000000000000000e30"),
2659          cpp_dec_float("2.535301200456458802993406410752000000000000000000000000000000000000000000000000000000000000000000000e30"),
2660          cpp_dec_float("5.070602400912917605986812821504000000000000000000000000000000000000000000000000000000000000000000000e30"),
2661          cpp_dec_float("1.014120480182583521197362564300800000000000000000000000000000000000000000000000000000000000000000000e31"),
2662          cpp_dec_float("2.028240960365167042394725128601600000000000000000000000000000000000000000000000000000000000000000000e31"),
2663          cpp_dec_float("4.056481920730334084789450257203200000000000000000000000000000000000000000000000000000000000000000000e31"),
2664          cpp_dec_float("8.112963841460668169578900514406400000000000000000000000000000000000000000000000000000000000000000000e31"),
2665          cpp_dec_float("1.622592768292133633915780102881280000000000000000000000000000000000000000000000000000000000000000000e32"),
2666          cpp_dec_float("3.245185536584267267831560205762560000000000000000000000000000000000000000000000000000000000000000000e32"),
2667          cpp_dec_float("6.490371073168534535663120411525120000000000000000000000000000000000000000000000000000000000000000000e32"),
2668          cpp_dec_float("1.298074214633706907132624082305024000000000000000000000000000000000000000000000000000000000000000000e33"),
2669          cpp_dec_float("2.596148429267413814265248164610048000000000000000000000000000000000000000000000000000000000000000000e33"),
2670          cpp_dec_float("5.192296858534827628530496329220096000000000000000000000000000000000000000000000000000000000000000000e33"),
2671          cpp_dec_float("1.038459371706965525706099265844019200000000000000000000000000000000000000000000000000000000000000000e34"),
2672          cpp_dec_float("2.076918743413931051412198531688038400000000000000000000000000000000000000000000000000000000000000000e34"),
2673          cpp_dec_float("4.153837486827862102824397063376076800000000000000000000000000000000000000000000000000000000000000000e34"),
2674          cpp_dec_float("8.307674973655724205648794126752153600000000000000000000000000000000000000000000000000000000000000000e34"),
2675          cpp_dec_float("1.661534994731144841129758825350430720000000000000000000000000000000000000000000000000000000000000000e35"),
2676          cpp_dec_float("3.323069989462289682259517650700861440000000000000000000000000000000000000000000000000000000000000000e35"),
2677          cpp_dec_float("6.646139978924579364519035301401722880000000000000000000000000000000000000000000000000000000000000000e35"),
2678          cpp_dec_float("1.329227995784915872903807060280344576000000000000000000000000000000000000000000000000000000000000000e36"),
2679          cpp_dec_float("2.658455991569831745807614120560689152000000000000000000000000000000000000000000000000000000000000000e36"),
2680          cpp_dec_float("5.316911983139663491615228241121378304000000000000000000000000000000000000000000000000000000000000000e36"),
2681          cpp_dec_float("1.063382396627932698323045648224275660800000000000000000000000000000000000000000000000000000000000000e37"),
2682          cpp_dec_float("2.126764793255865396646091296448551321600000000000000000000000000000000000000000000000000000000000000e37"),
2683          cpp_dec_float("4.253529586511730793292182592897102643200000000000000000000000000000000000000000000000000000000000000e37"),
2684          cpp_dec_float("8.507059173023461586584365185794205286400000000000000000000000000000000000000000000000000000000000000e37"),
2685          cpp_dec_float("1.701411834604692317316873037158841057280000000000000000000000000000000000000000000000000000000000000e38")}};
2686 
2687    if ((p > static_cast<boost::long_long_type>(-128)) && (p < static_cast<boost::long_long_type>(+128)))
2688    {
2689       return p2_data[static_cast<std::size_t>(p + ((p2_data.size() - 1u) / 2u))];
2690    }
2691    else
2692    {
2693       // Compute and return 2^p.
2694       if (p < static_cast<boost::long_long_type>(0))
2695       {
2696          return pow2(static_cast<boost::long_long_type>(-p)).calculate_inv();
2697       }
2698       else
2699       {
2700          cpp_dec_float<Digits10, ExponentType, Allocator> t;
2701          default_ops::detail::pow_imp(t, two(), p, mpl::true_());
2702          return t;
2703       }
2704    }
2705 }
2706 
2707 template <unsigned Digits10, class ExponentType, class Allocator>
eval_add(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & o)2708 inline void eval_add(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& o)
2709 {
2710    result += o;
2711 }
2712 template <unsigned Digits10, class ExponentType, class Allocator>
eval_subtract(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & o)2713 inline void eval_subtract(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& o)
2714 {
2715    result -= o;
2716 }
2717 template <unsigned Digits10, class ExponentType, class Allocator>
eval_multiply(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & o)2718 inline void eval_multiply(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& o)
2719 {
2720    result *= o;
2721 }
2722 template <unsigned Digits10, class ExponentType, class Allocator>
eval_divide(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & o)2723 inline void eval_divide(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& o)
2724 {
2725    result /= o;
2726 }
2727 
2728 template <unsigned Digits10, class ExponentType, class Allocator>
eval_add(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const boost::ulong_long_type & o)2729 inline void eval_add(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const boost::ulong_long_type& o)
2730 {
2731    result.add_unsigned_long_long(o);
2732 }
2733 template <unsigned Digits10, class ExponentType, class Allocator>
eval_subtract(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const boost::ulong_long_type & o)2734 inline void eval_subtract(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const boost::ulong_long_type& o)
2735 {
2736    result.sub_unsigned_long_long(o);
2737 }
2738 template <unsigned Digits10, class ExponentType, class Allocator>
eval_multiply(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const boost::ulong_long_type & o)2739 inline void eval_multiply(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const boost::ulong_long_type& o)
2740 {
2741    result.mul_unsigned_long_long(o);
2742 }
2743 template <unsigned Digits10, class ExponentType, class Allocator>
eval_divide(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const boost::ulong_long_type & o)2744 inline void eval_divide(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const boost::ulong_long_type& o)
2745 {
2746    result.div_unsigned_long_long(o);
2747 }
2748 
2749 template <unsigned Digits10, class ExponentType, class Allocator>
eval_add(cpp_dec_float<Digits10,ExponentType,Allocator> & result,boost::long_long_type o)2750 inline void eval_add(cpp_dec_float<Digits10, ExponentType, Allocator>& result, boost::long_long_type o)
2751 {
2752    if (o < 0)
2753       result.sub_unsigned_long_long(boost::multiprecision::detail::unsigned_abs(o));
2754    else
2755       result.add_unsigned_long_long(o);
2756 }
2757 template <unsigned Digits10, class ExponentType, class Allocator>
eval_subtract(cpp_dec_float<Digits10,ExponentType,Allocator> & result,boost::long_long_type o)2758 inline void eval_subtract(cpp_dec_float<Digits10, ExponentType, Allocator>& result, boost::long_long_type o)
2759 {
2760    if (o < 0)
2761       result.add_unsigned_long_long(boost::multiprecision::detail::unsigned_abs(o));
2762    else
2763       result.sub_unsigned_long_long(o);
2764 }
2765 template <unsigned Digits10, class ExponentType, class Allocator>
eval_multiply(cpp_dec_float<Digits10,ExponentType,Allocator> & result,boost::long_long_type o)2766 inline void eval_multiply(cpp_dec_float<Digits10, ExponentType, Allocator>& result, boost::long_long_type o)
2767 {
2768    if (o < 0)
2769    {
2770       result.mul_unsigned_long_long(boost::multiprecision::detail::unsigned_abs(o));
2771       result.negate();
2772    }
2773    else
2774       result.mul_unsigned_long_long(o);
2775 }
2776 template <unsigned Digits10, class ExponentType, class Allocator>
eval_divide(cpp_dec_float<Digits10,ExponentType,Allocator> & result,boost::long_long_type o)2777 inline void eval_divide(cpp_dec_float<Digits10, ExponentType, Allocator>& result, boost::long_long_type o)
2778 {
2779    if (o < 0)
2780    {
2781       result.div_unsigned_long_long(boost::multiprecision::detail::unsigned_abs(o));
2782       result.negate();
2783    }
2784    else
2785       result.div_unsigned_long_long(o);
2786 }
2787 
2788 template <unsigned Digits10, class ExponentType, class Allocator>
eval_convert_to(boost::ulong_long_type * result,const cpp_dec_float<Digits10,ExponentType,Allocator> & val)2789 inline void eval_convert_to(boost::ulong_long_type* result, const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
2790 {
2791    *result = val.extract_unsigned_long_long();
2792 }
2793 template <unsigned Digits10, class ExponentType, class Allocator>
eval_convert_to(boost::long_long_type * result,const cpp_dec_float<Digits10,ExponentType,Allocator> & val)2794 inline void eval_convert_to(boost::long_long_type* result, const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
2795 {
2796    *result = val.extract_signed_long_long();
2797 }
2798 template <unsigned Digits10, class ExponentType, class Allocator>
eval_convert_to(long double * result,const cpp_dec_float<Digits10,ExponentType,Allocator> & val)2799 inline void eval_convert_to(long double* result, const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
2800 {
2801    *result = val.extract_long_double();
2802 }
2803 template <unsigned Digits10, class ExponentType, class Allocator>
eval_convert_to(double * result,const cpp_dec_float<Digits10,ExponentType,Allocator> & val)2804 inline void eval_convert_to(double* result, const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
2805 {
2806    *result = val.extract_double();
2807 }
2808 
2809 //
2810 // Non member function support:
2811 //
2812 template <unsigned Digits10, class ExponentType, class Allocator>
eval_fpclassify(const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2813 inline int eval_fpclassify(const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2814 {
2815    if ((x.isinf)())
2816       return FP_INFINITE;
2817    if ((x.isnan)())
2818       return FP_NAN;
2819    if (x.iszero())
2820       return FP_ZERO;
2821    return FP_NORMAL;
2822 }
2823 
2824 template <unsigned Digits10, class ExponentType, class Allocator>
eval_abs(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2825 inline void eval_abs(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2826 {
2827    result = x;
2828    if (x.isneg())
2829       result.negate();
2830 }
2831 
2832 template <unsigned Digits10, class ExponentType, class Allocator>
eval_fabs(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2833 inline void eval_fabs(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2834 {
2835    result = x;
2836    if (x.isneg())
2837       result.negate();
2838 }
2839 
2840 template <unsigned Digits10, class ExponentType, class Allocator>
eval_sqrt(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2841 inline void eval_sqrt(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2842 {
2843    result = x;
2844    result.calculate_sqrt();
2845 }
2846 
2847 template <unsigned Digits10, class ExponentType, class Allocator>
eval_floor(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2848 inline void eval_floor(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2849 {
2850    result = x;
2851    if (!(x.isfinite)() || x.isint())
2852    {
2853       if ((x.isnan)())
2854          errno = EDOM;
2855       return;
2856    }
2857 
2858    if (x.isneg())
2859       result -= cpp_dec_float<Digits10, ExponentType, Allocator>::one();
2860    result = result.extract_integer_part();
2861 }
2862 
2863 template <unsigned Digits10, class ExponentType, class Allocator>
eval_ceil(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2864 inline void eval_ceil(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2865 {
2866    result = x;
2867    if (!(x.isfinite)() || x.isint())
2868    {
2869       if ((x.isnan)())
2870          errno = EDOM;
2871       return;
2872    }
2873 
2874    if (!x.isneg())
2875       result += cpp_dec_float<Digits10, ExponentType, Allocator>::one();
2876    result = result.extract_integer_part();
2877 }
2878 
2879 template <unsigned Digits10, class ExponentType, class Allocator>
eval_trunc(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x)2880 inline void eval_trunc(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x)
2881 {
2882    if (x.isint() || !(x.isfinite)())
2883    {
2884       result = x;
2885       if ((x.isnan)())
2886          errno = EDOM;
2887       return;
2888    }
2889    result = x.extract_integer_part();
2890 }
2891 
2892 template <unsigned Digits10, class ExponentType, class Allocator>
eval_ilogb(const cpp_dec_float<Digits10,ExponentType,Allocator> & val)2893 inline ExponentType eval_ilogb(const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
2894 {
2895    if (val.iszero())
2896       return (std::numeric_limits<ExponentType>::min)();
2897    if ((val.isinf)())
2898       return INT_MAX;
2899    if ((val.isnan)())
2900 #ifdef FP_ILOGBNAN
2901       return FP_ILOGBNAN;
2902 #else
2903       return INT_MAX;
2904 #endif
2905    // Set result, to the exponent of val:
2906    return val.order();
2907 }
2908 template <unsigned Digits10, class ExponentType, class Allocator, class ArgType>
eval_scalbn(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & val,ArgType e_)2909 inline void eval_scalbn(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& val, ArgType e_)
2910 {
2911    using default_ops::eval_multiply;
2912    const ExponentType                               e = static_cast<ExponentType>(e_);
2913    cpp_dec_float<Digits10, ExponentType, Allocator> t(1.0, e);
2914    eval_multiply(result, val, t);
2915 }
2916 
2917 template <unsigned Digits10, class ExponentType, class Allocator, class ArgType>
eval_ldexp(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x,ArgType e)2918 inline void eval_ldexp(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x, ArgType e)
2919 {
2920    const boost::long_long_type the_exp = static_cast<boost::long_long_type>(e);
2921 
2922    if ((the_exp > (std::numeric_limits<ExponentType>::max)()) || (the_exp < (std::numeric_limits<ExponentType>::min)()))
2923       BOOST_THROW_EXCEPTION(std::runtime_error(std::string("Exponent value is out of range.")));
2924 
2925    result = x;
2926 
2927    if ((the_exp > static_cast<boost::long_long_type>(-std::numeric_limits<boost::long_long_type>::digits)) && (the_exp < static_cast<boost::long_long_type>(0)))
2928       result.div_unsigned_long_long(1ULL << static_cast<boost::long_long_type>(-the_exp));
2929    else if ((the_exp < static_cast<boost::long_long_type>(std::numeric_limits<boost::long_long_type>::digits)) && (the_exp > static_cast<boost::long_long_type>(0)))
2930       result.mul_unsigned_long_long(1ULL << the_exp);
2931    else if (the_exp != static_cast<boost::long_long_type>(0))
2932       result *= cpp_dec_float<Digits10, ExponentType, Allocator>::pow2(e);
2933 }
2934 
2935 template <unsigned Digits10, class ExponentType, class Allocator>
eval_frexp(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x,ExponentType * e)2936 inline void eval_frexp(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x, ExponentType* e)
2937 {
2938    result = x;
2939 
2940    if (result.iszero() || (result.isinf)() || (result.isnan)())
2941    {
2942       *e = 0;
2943       return;
2944    }
2945 
2946    if (result.isneg())
2947       result.negate();
2948 
2949    ExponentType t = result.order();
2950    BOOST_MP_USING_ABS
2951    if (abs(t) < ((std::numeric_limits<ExponentType>::max)() / 1000))
2952    {
2953       t *= 1000;
2954       t /= 301;
2955    }
2956    else
2957    {
2958       t /= 301;
2959       t *= 1000;
2960    }
2961 
2962    result *= cpp_dec_float<Digits10, ExponentType, Allocator>::pow2(-t);
2963 
2964    if (result.iszero() || (result.isinf)() || (result.isnan)())
2965    {
2966       // pow2 overflowed, slip the calculation up:
2967       result = x;
2968       if (result.isneg())
2969          result.negate();
2970       t /= 2;
2971       result *= cpp_dec_float<Digits10, ExponentType, Allocator>::pow2(-t);
2972    }
2973    BOOST_MP_USING_ABS
2974    if (abs(result.order()) > 5)
2975    {
2976       // If our first estimate doesn't get close enough then try recursion until we do:
2977       ExponentType                                     e2;
2978       cpp_dec_float<Digits10, ExponentType, Allocator> r2;
2979       eval_frexp(r2, result, &e2);
2980       // overflow protection:
2981       if ((t > 0) && (e2 > 0) && (t > (std::numeric_limits<ExponentType>::max)() - e2))
2982          BOOST_THROW_EXCEPTION(std::runtime_error("Exponent is too large to be represented as a power of 2."));
2983       if ((t < 0) && (e2 < 0) && (t < (std::numeric_limits<ExponentType>::min)() - e2))
2984          BOOST_THROW_EXCEPTION(std::runtime_error("Exponent is too large to be represented as a power of 2."));
2985       t += e2;
2986       result = r2;
2987    }
2988 
2989    while (result.compare(cpp_dec_float<Digits10, ExponentType, Allocator>::one()) >= 0)
2990    {
2991       result /= cpp_dec_float<Digits10, ExponentType, Allocator>::two();
2992       ++t;
2993    }
2994    while (result.compare(cpp_dec_float<Digits10, ExponentType, Allocator>::half()) < 0)
2995    {
2996       result *= cpp_dec_float<Digits10, ExponentType, Allocator>::two();
2997       --t;
2998    }
2999    *e = t;
3000    if (x.isneg())
3001       result.negate();
3002 }
3003 
3004 template <unsigned Digits10, class ExponentType, class Allocator>
eval_frexp(cpp_dec_float<Digits10,ExponentType,Allocator> & result,const cpp_dec_float<Digits10,ExponentType,Allocator> & x,int * e)3005 inline typename disable_if<is_same<ExponentType, int> >::type eval_frexp(cpp_dec_float<Digits10, ExponentType, Allocator>& result, const cpp_dec_float<Digits10, ExponentType, Allocator>& x, int* e)
3006 {
3007    ExponentType t;
3008    eval_frexp(result, x, &t);
3009    if ((t > (std::numeric_limits<int>::max)()) || (t < (std::numeric_limits<int>::min)()))
3010       BOOST_THROW_EXCEPTION(std::runtime_error("Exponent is outside the range of an int"));
3011    *e = static_cast<int>(t);
3012 }
3013 
3014 template <unsigned Digits10, class ExponentType, class Allocator>
eval_is_zero(const cpp_dec_float<Digits10,ExponentType,Allocator> & val)3015 inline bool eval_is_zero(const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
3016 {
3017    return val.iszero();
3018 }
3019 template <unsigned Digits10, class ExponentType, class Allocator>
eval_get_sign(const cpp_dec_float<Digits10,ExponentType,Allocator> & val)3020 inline int eval_get_sign(const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
3021 {
3022    return val.iszero() ? 0 : val.isneg() ? -1 : 1;
3023 }
3024 
3025 template <unsigned Digits10, class ExponentType, class Allocator>
hash_value(const cpp_dec_float<Digits10,ExponentType,Allocator> & val)3026 inline std::size_t hash_value(const cpp_dec_float<Digits10, ExponentType, Allocator>& val)
3027 {
3028    return val.hash();
3029 }
3030 
3031 } // namespace backends
3032 
3033 using boost::multiprecision::backends::cpp_dec_float;
3034 
3035 typedef number<cpp_dec_float<50> >  cpp_dec_float_50;
3036 typedef number<cpp_dec_float<100> > cpp_dec_float_100;
3037 
3038 #ifdef BOOST_NO_SFINAE_EXPR
3039 
3040 namespace detail {
3041 
3042 template <unsigned D1, class E1, class A1, unsigned D2, class E2, class A2>
3043 struct is_explicitly_convertible<cpp_dec_float<D1, E1, A1>, cpp_dec_float<D2, E2, A2> > : public mpl::true_
3044 {};
3045 
3046 } // namespace detail
3047 
3048 #endif
3049 
3050 }} // namespace boost::multiprecision
3051 
3052 namespace std {
3053 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3054 class numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >
3055 {
3056  public:
3057    BOOST_STATIC_CONSTEXPR bool is_specialized                      = true;
3058    BOOST_STATIC_CONSTEXPR bool is_signed                           = true;
3059    BOOST_STATIC_CONSTEXPR bool is_integer                          = false;
3060    BOOST_STATIC_CONSTEXPR bool is_exact                            = false;
3061    BOOST_STATIC_CONSTEXPR bool is_bounded                          = true;
3062    BOOST_STATIC_CONSTEXPR bool is_modulo                           = false;
3063    BOOST_STATIC_CONSTEXPR bool is_iec559                           = false;
3064    BOOST_STATIC_CONSTEXPR int  digits                              = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10;
3065    BOOST_STATIC_CONSTEXPR int  digits10                            = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10;
3066    BOOST_STATIC_CONSTEXPR int  max_digits10                        = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_total_digits10;
3067    BOOST_STATIC_CONSTEXPR ExponentType min_exponent                = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_min_exp;   // Type differs from int.
3068    BOOST_STATIC_CONSTEXPR ExponentType min_exponent10              = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_min_exp10; // Type differs from int.
3069    BOOST_STATIC_CONSTEXPR ExponentType max_exponent                = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_max_exp;   // Type differs from int.
3070    BOOST_STATIC_CONSTEXPR ExponentType max_exponent10              = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_max_exp10; // Type differs from int.
3071    BOOST_STATIC_CONSTEXPR int          radix                       = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_radix;
3072    BOOST_STATIC_CONSTEXPR std::float_round_style round_style       = std::round_indeterminate;
3073    BOOST_STATIC_CONSTEXPR bool                   has_infinity      = true;
3074    BOOST_STATIC_CONSTEXPR bool                   has_quiet_NaN     = true;
3075    BOOST_STATIC_CONSTEXPR bool                   has_signaling_NaN = false;
3076    BOOST_STATIC_CONSTEXPR std::float_denorm_style has_denorm       = std::denorm_absent;
3077    BOOST_STATIC_CONSTEXPR bool                    has_denorm_loss  = false;
3078    BOOST_STATIC_CONSTEXPR bool                    traps            = false;
3079    BOOST_STATIC_CONSTEXPR bool                    tinyness_before  = false;
3080 
3081    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates>(min)() { return (boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::min)(); }
3082    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates>(max)() { return (boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::max)(); }
lowest()3083    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> lowest() { return boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::zero(); }
epsilon()3084    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> epsilon() { return boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::eps(); }
round_error()3085    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> round_error() { return 0.5L; }
infinity()3086    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> infinity() { return boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::inf(); }
quiet_NaN()3087    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> quiet_NaN() { return boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::nan(); }
signaling_NaN()3088    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> signaling_NaN() { return boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::zero(); }
denorm_min()3089    BOOST_STATIC_CONSTEXPR boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> denorm_min() { return boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::zero(); }
3090 };
3091 
3092 #ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
3093 
3094 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3095 BOOST_CONSTEXPR_OR_CONST int numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::digits;
3096 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3097 BOOST_CONSTEXPR_OR_CONST int numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::digits10;
3098 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3099 BOOST_CONSTEXPR_OR_CONST int numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::max_digits10;
3100 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3101 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::is_signed;
3102 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3103 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::is_integer;
3104 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3105 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::is_exact;
3106 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3107 BOOST_CONSTEXPR_OR_CONST int numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::radix;
3108 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3109 BOOST_CONSTEXPR_OR_CONST ExponentType numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::min_exponent;
3110 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3111 BOOST_CONSTEXPR_OR_CONST ExponentType numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::min_exponent10;
3112 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3113 BOOST_CONSTEXPR_OR_CONST ExponentType numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::max_exponent;
3114 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3115 BOOST_CONSTEXPR_OR_CONST ExponentType numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::max_exponent10;
3116 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3117 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::has_infinity;
3118 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3119 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::has_quiet_NaN;
3120 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3121 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::has_signaling_NaN;
3122 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3123 BOOST_CONSTEXPR_OR_CONST float_denorm_style numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::has_denorm;
3124 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3125 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::has_denorm_loss;
3126 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3127 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::is_iec559;
3128 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3129 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::is_bounded;
3130 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3131 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::is_modulo;
3132 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3133 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::traps;
3134 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3135 BOOST_CONSTEXPR_OR_CONST bool numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::tinyness_before;
3136 template <unsigned Digits10, class ExponentType, class Allocator, boost::multiprecision::expression_template_option ExpressionTemplates>
3137 BOOST_CONSTEXPR_OR_CONST float_round_style numeric_limits<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates> >::round_style;
3138 
3139 #endif
3140 } // namespace std
3141 
3142 namespace boost {
3143 namespace math {
3144 
3145 namespace policies {
3146 
3147 template <unsigned Digits10, class ExponentType, class Allocator, class Policy, boost::multiprecision::expression_template_option ExpressionTemplates>
3148 struct precision<boost::multiprecision::number<boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>, ExpressionTemplates>, Policy>
3149 {
3150    // Define a local copy of cpp_dec_float_digits10 because it might differ
3151    // from the template parameter Digits10 for small or large digit counts.
3152    static const boost::int32_t cpp_dec_float_digits10 = boost::multiprecision::cpp_dec_float<Digits10, ExponentType, Allocator>::cpp_dec_float_digits10;
3153 
3154    typedef typename Policy::precision_type                            precision_type;
3155    typedef digits2<((cpp_dec_float_digits10 + 1LL) * 1000LL) / 301LL> digits_2;
3156    typedef typename mpl::if_c<
3157        ((digits_2::value <= precision_type::value) || (Policy::precision_type::value <= 0)),
3158        // Default case, full precision for RealType:
3159        digits_2,
3160        // User customized precision:
3161        precision_type>::type type;
3162 };
3163 
3164 }
3165 
3166 }} // namespace boost::math::policies
3167 
3168 #ifdef BOOST_MSVC
3169 #pragma warning(pop)
3170 #endif
3171 
3172 #endif
3173