test: epoc32/include/stdapis/boost/functional/detail/hash

     2 //  Copyright Daniel James 2005-2006. Use, modification, and distribution are

     3 //  subject to the Boost Software License, Version 1.0. (See accompanying

     4 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

     6 //  Based on Peter Dimov's proposal

     7 //  http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf

     8 //  issue 6.18.

    10 #if !defined(BOOST_FUNCTIONAL_DETAIL_HASH_FLOAT_HEADER)

    11 #define BOOST_FUNCTIONAL_DETAIL_HASH_FLOAT_HEADER

    13 #if defined(_MSC_VER) && (_MSC_VER >= 1020)

    14 # pragma once

    15 #endif

    17 #include <boost/functional/detail/float_functions.hpp>

    18 #include <boost/limits.hpp>

    19 #include <boost/assert.hpp>

    20 #include <errno.h>

    22 // Don't use fpclassify or _fpclass for stlport.

    23 #if !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION)

    24 #  if defined(__GLIBCPP__) || defined(__GLIBCXX__)

    25 // GNU libstdc++ 3

    26 #    if (defined(__USE_ISOC99) || defined(_GLIBCXX_USE_C99_MATH)) && \

    27         !(defined(macintosh) || defined(__APPLE__) || defined(__APPLE_CC__))

    28 #      define BOOST_HASH_USE_FPCLASSIFY

    29 #    endif

    30 #  elif (defined(_YVALS) && !defined(__IBMCPP__)) || defined(_CPPLIB_VER)

    31 // Dinkumware Library, on Visual C++

    32 #    if defined(BOOST_MSVC)

    33 #      define BOOST_HASH_USE_FPCLASS

    34 #    endif

    35 #  endif

    36 #endif

    38 namespace boost

    39 {

    40     namespace hash_detail

    41     {

    42         inline void hash_float_combine(std::size_t& seed, std::size_t value)

    43         {

    44             seed ^= value + (seed<<6) + (seed>>2);

    45         }

    47         template <class T>

    48         inline std::size_t float_hash_impl(T v)

    49         {

    50             int exp = 0;

    51             errno = 0;

    52             v = boost::hash_detail::call_frexp(v, &exp);

    53             if(errno) return 0;

    55             std::size_t seed = 0;

    57             std::size_t const length

    58                 = (std::numeric_limits<T>::digits +

    59                         std::numeric_limits<int>::digits - 1)

    60                 / std::numeric_limits<int>::digits;

    62             for(std::size_t i = 0; i < length; ++i)

    63             {

    64                 v = boost::hash_detail::call_ldexp(v, std::numeric_limits<int>::digits);

    65                 int const part = static_cast<int>(v);

    66                 v -= part;

    67                 hash_float_combine(seed, part);

    68             }

    70             hash_float_combine(seed, exp);

    72             return seed;

    73         }

    75         template <class T>

    76         inline std::size_t float_hash_value(T v)

    77         {

    78 #if defined(BOOST_HASH_USE_FPCLASSIFY)

    79             using namespace std;

    80             switch (fpclassify(v)) {

    81             case FP_ZERO:

    82                 return 0;

    83             case FP_INFINITE:

    84                 return (std::size_t)(v > 0 ? -1 : -2);

    85             case FP_NAN:

    86                 return (std::size_t)(-3);

    87             case FP_NORMAL:

    88             case FP_SUBNORMAL:

    89                 return float_hash_impl(v);

    90             default:

    91                 BOOST_ASSERT(0);

    92                 return 0;

    93             }

    94 #elif defined(BOOST_HASH_USE_FPCLASS)

    95             switch(_fpclass(v)) {

    96             case _FPCLASS_NZ:

    97             case _FPCLASS_PZ:

    98                 return 0;

    99             case _FPCLASS_PINF:

   100                 return (std::size_t)(-1);

   101             case _FPCLASS_NINF:

   102                 return (std::size_t)(-2);

   103             case _FPCLASS_SNAN:

   104             case _FPCLASS_QNAN:

   105                 return (std::size_t)(-3);

   106             case _FPCLASS_NN:

   107             case _FPCLASS_ND:

   108                 return float_hash_impl(v);

   109             case _FPCLASS_PD:

   110             case _FPCLASS_PN:

   111                 return float_hash_impl(v);

   112             default:

   113                 BOOST_ASSERT(0);

   114                 return 0;

   115             }

   116 #else

   117             return float_hash_impl(v);

   118 #endif

   119         }

   120     }

   121 }

   123 #endif

author	William Roberts <williamr@symbian.org>
	Wed, 31 Mar 2010 12:27:01 +0100
branch	Symbian2
changeset 3	e1b950c65cb4
permissions	-rw-r--r--