X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=libstdc%2B%2B-v3%2Finclude%2Ftr1_impl%2Ffunctional_hash.h;fp=libstdc%2B%2B-v3%2Finclude%2Ftr1_impl%2Ffunctional_hash.h;h=665168c0f5fe34f318f76e410eb4c5068e12c9e2;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/libstdc++-v3/include/tr1_impl/functional_hash.h b/libstdc++-v3/include/tr1_impl/functional_hash.h new file mode 100644 index 00000000..665168c0 --- /dev/null +++ b/libstdc++-v3/include/tr1_impl/functional_hash.h @@ -0,0 +1,183 @@ +// TR1 functional -*- C++ -*- + +// Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// . + +/** @file tr1_impl/functional_hash.h + * This is an internal header file, included by other library headers. + * You should not attempt to use it directly. + */ + +namespace std +{ +_GLIBCXX_BEGIN_NAMESPACE_TR1 + + /// Class template hash. + // Declaration of default hash functor std::tr1::hash. The types for + // which std::tr1::hash is well-defined is in clause 6.3.3. of the PDTR. + template + struct hash : public std::unary_function<_Tp, size_t> + { + size_t + operator()(_Tp __val) const; + }; + + /// Partial specializations for pointer types. + template + struct hash<_Tp*> : public std::unary_function<_Tp*, size_t> + { + size_t + operator()(_Tp* __p) const + { return reinterpret_cast(__p); } + }; + + /// Explicit specializations for integer types. +#define _TR1_hashtable_define_trivial_hash(_Tp) \ + template<> \ + inline size_t \ + hash<_Tp>::operator()(_Tp __val) const \ + { return static_cast(__val); } + + _TR1_hashtable_define_trivial_hash(bool); + _TR1_hashtable_define_trivial_hash(char); + _TR1_hashtable_define_trivial_hash(signed char); + _TR1_hashtable_define_trivial_hash(unsigned char); + _TR1_hashtable_define_trivial_hash(wchar_t); +#ifdef _GLIBCXX_INCLUDE_AS_CXX0X + _TR1_hashtable_define_trivial_hash(char16_t); + _TR1_hashtable_define_trivial_hash(char32_t); +#endif + _TR1_hashtable_define_trivial_hash(short); + _TR1_hashtable_define_trivial_hash(int); + _TR1_hashtable_define_trivial_hash(long); + _TR1_hashtable_define_trivial_hash(long long); + _TR1_hashtable_define_trivial_hash(unsigned short); + _TR1_hashtable_define_trivial_hash(unsigned int); + _TR1_hashtable_define_trivial_hash(unsigned long); + _TR1_hashtable_define_trivial_hash(unsigned long long); + +#undef _TR1_hashtable_define_trivial_hash + + // Fowler / Noll / Vo (FNV) Hash (type FNV-1a) + // (Used by the next specializations of std::tr1::hash.) + + /// Dummy generic implementation (for sizeof(size_t) != 4, 8). + template + struct _Fnv_hash + { + static size_t + hash(const char* __first, size_t __length) + { + size_t __result = 0; + for (; __length > 0; --__length) + __result = (__result * 131) + *__first++; + return __result; + } + }; + + template<> + struct _Fnv_hash<4> + { + static size_t + hash(const char* __first, size_t __length) + { + size_t __result = static_cast(2166136261UL); + for (; __length > 0; --__length) + { + __result ^= static_cast(*__first++); + __result *= static_cast(16777619UL); + } + return __result; + } + }; + + template<> + struct _Fnv_hash<8> + { + static size_t + hash(const char* __first, size_t __length) + { + size_t __result = + static_cast(14695981039346656037ULL); + for (; __length > 0; --__length) + { + __result ^= static_cast(*__first++); + __result *= static_cast(1099511628211ULL); + } + return __result; + } + }; + + /// Explicit specializations for float. + template<> + inline size_t + hash::operator()(float __val) const + { + size_t __result = 0; + + // 0 and -0 both hash to zero. + if (__val != 0.0f) + __result = _Fnv_hash<>::hash(reinterpret_cast(&__val), + sizeof(__val)); + return __result; + }; + + /// Explicit specializations for double. + template<> + inline size_t + hash::operator()(double __val) const + { + size_t __result = 0; + + // 0 and -0 both hash to zero. + if (__val != 0.0) + __result = _Fnv_hash<>::hash(reinterpret_cast(&__val), + sizeof(__val)); + return __result; + }; + + /// Explicit specializations for long double. + template<> + size_t + hash::operator()(long double __val) const; + + /// Explicit specialization of member operator for non-builtin types. + template<> + size_t + hash::operator()(string) const; + + template<> + size_t + hash::operator()(const string&) const; + +#ifdef _GLIBCXX_USE_WCHAR_T + template<> + size_t + hash::operator()(wstring) const; + + template<> + size_t + hash::operator()(const wstring&) const; +#endif + +_GLIBCXX_END_NAMESPACE_TR1 +}