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Fixes to hash for long long, unsigned long long, float, double and long double. Credit Dave Zarzycki

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git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@145721 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Howard Hinnant 2011-12-02 22:52:09 +00:00
parent f836d531b4
commit 62453ea71d
1 changed files with 56 additions and 22 deletions
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78
include/functional
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@ -1921,11 +1921,19 @@ struct _LIBCPP_VISIBLE hash<long long>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_INLINE_VISIBILITY
size_t operator()(long long __v) const _NOEXCEPT size_t operator()(long long __v) const _NOEXCEPT
{ {
size_t __r = 0; #ifdef __LP64__
const size_t* const __p = reinterpret_cast<const size_t*>(&__v); return __v;
for (unsigned __i = 0; __i < sizeof(argument_type)/sizeof(size_t); ++__i) #else
__r ^= __p[__i]; union {
return __r; long long __l;
struct {
int __a;
int __b;
} __s;
} __u;
__u.__l = __v;
return __u.__s.__a ^ __u.__s.__b;
#endif
} }
}; };
@ -1936,11 +1944,19 @@ struct _LIBCPP_VISIBLE hash<unsigned long long>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_INLINE_VISIBILITY
size_t operator()(unsigned long long __v) const _NOEXCEPT size_t operator()(unsigned long long __v) const _NOEXCEPT
{ {
size_t __r = 0; #ifdef __LP64__
const size_t* const __p = reinterpret_cast<const size_t*>(&__v); return __v;
for (unsigned __i = 0; __i < sizeof(argument_type)/sizeof(size_t); ++__i) #else
__r ^= __p[__i]; union {
return __r; unsigned long long __ul;
struct {
int __a;
int __b;
} __s;
} __u;
__u.__ul = __v;
return __u.__s.__a ^ __u.__s.__b;
#endif
} }
}; };
@ -1951,10 +1967,18 @@ struct _LIBCPP_VISIBLE hash<float>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_INLINE_VISIBILITY
size_t operator()(float __v) const _NOEXCEPT size_t operator()(float __v) const _NOEXCEPT
{ {
union {
#ifdef __LP64__
double __f;
#else
float __f;
#endif
size_t __d;
} __u;
if (__v == 0) if (__v == 0)
return 0; return 0;
const size_t* const __p = reinterpret_cast<const size_t*>(&__v); __u.__f = __v;
return *__p; return __u.__d;
} }
}; };
@ -1965,13 +1989,18 @@ struct _LIBCPP_VISIBLE hash<double>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_INLINE_VISIBILITY
size_t operator()(double __v) const _NOEXCEPT size_t operator()(double __v) const _NOEXCEPT
{ {
union {
#ifdef __LP64__
double __f;
#else
float __f;
#endif
size_t __d;
} __u;
if (__v == 0) if (__v == 0)
return 0; return 0;
size_t __r = 0; __u.__f = __v;
const size_t* const __p = reinterpret_cast<const size_t*>(&__v); return __u.__d;
for (unsigned __i = 0; __i < sizeof(argument_type)/sizeof(size_t); ++__i)
__r ^= __p[__i];
return __r;
} }
}; };
@ -1982,13 +2011,18 @@ struct _LIBCPP_VISIBLE hash<long double>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_INLINE_VISIBILITY
size_t operator()(long double __v) const _NOEXCEPT size_t operator()(long double __v) const _NOEXCEPT
{ {
union {
#ifdef __LP64__
double __f;
#else
float __f;
#endif
size_t __d;
} __u;
if (__v == 0) if (__v == 0)
return 0; return 0;
size_t __r = 0; __u.__f = __v;
const size_t* const __p = reinterpret_cast<const size_t*>(&__v); return __u.__d;
for (unsigned __i = 0; __i < sizeof(argument_type)/sizeof(size_t); ++__i)
__r ^= __p[__i];
return __r;
} }
}; };