feedc0de/boost_container_hash
1
0
Fork 0
forked from boostorg/container_hash
Code Pull Requests Activity

Simpler test for appropriate floats for binary hashing. Refs #8822.

Browse Source 
No idea if this will actually fix it.

[SVN r85246]
This commit is contained in:
Daniel James
2013-08-08 20:30:04 +00:00
parent 0d6cee7e64
commit 1870aa9534
1 changed files with 13 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
include/boost/functional/hash/detail/hash_float.hpp
View File

@@ -90,15 +90,20 @@ namespace boost
return seed;
}
template <typename Float, unsigned digits, unsigned max_exponent>
struct enable_binary_hash
{
BOOST_STATIC_CONSTANT(bool, value =
std::numeric_limits<Float>::is_iec559 &&
std::numeric_limits<Float>::digits == digits &&
std::numeric_limits<Float>::radix == 2 &&
std::numeric_limits<Float>::max_exponent == max_exponent);
};
template <typename Float>
inline std::size_t float_hash_impl(Float v,
BOOST_DEDUCED_TYPENAME boost::enable_if_c<
std::numeric_limits<Float>::is_iec559 &&
std::numeric_limits<Float>::digits == 24 &&
std::numeric_limits<Float>::radix == 2 &&
std::numeric_limits<Float>::max_exponent == 128,
int>::type
)
enable_binary_hash<Float, 24, 128>::value, int>::type)
{
return hash_binary((char*) &v, 4);
}
@@ -107,12 +112,7 @@ namespace boost
template <typename Float>
inline std::size_t float_hash_impl(Float v,
BOOST_DEDUCED_TYPENAME boost::enable_if_c<
std::numeric_limits<Float>::is_iec559 &&
std::numeric_limits<Float>::digits == 53 &&
std::numeric_limits<Float>::radix == 2 &&
std::numeric_limits<Float>::max_exponent == 1024,
int>::type
)
enable_binary_hash<Float, 53, 1024>::value, int>::type)
{
return hash_binary((char*) &v, 8);
}
@@ -120,12 +120,7 @@ namespace boost
template <typename Float>
inline std::size_t float_hash_impl(Float v,
BOOST_DEDUCED_TYPENAME boost::enable_if_c<
std::numeric_limits<Float>::is_iec559 &&
std::numeric_limits<Float>::digits == 64 &&
std::numeric_limits<Float>::radix == 2 &&
std::numeric_limits<Float>::max_exponent == 16384,
int>::type
)
enable_binary_hash<Float, 64, 16384>::value, int>::type)
{
return hash_binary((char*) &v, 10);
}