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Full namespace for std::size_t.

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[SVN r37779]
This commit is contained in:
Daniel James
2007-05-25 23:58:33 +00:00
parent 7e023df182
commit 67efd5c627
1 changed files with 10 additions and 10 deletions
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20
include/boost/functional/hash/hash.hpp
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@@ -96,42 +96,42 @@ namespace boost
namespace hash_detail namespace hash_detail
{ {
template <class T> template <class T>
inline size_t hash_value_signed(T val) inline std::size_t hash_value_signed(T val)
{ {
const int size_t_bits = std::numeric_limits<size_t>::digits; const int size_t_bits = std::numeric_limits<std::size_t>::digits;
// ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1 // ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
const int length = (std::numeric_limits<T>::digits - 1) const int length = (std::numeric_limits<T>::digits - 1)
/ size_t_bits; / size_t_bits;
size_t seed = 0; std::size_t seed = 0;
T positive = val < 0 ? -1 - val : val; T positive = val < 0 ? -1 - val : val;
// Hopefully, this loop can be unrolled. // Hopefully, this loop can be unrolled.
for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits) for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits)
{ {
seed ^= (size_t) (positive >> i) + (seed<<6) + (seed>>2); seed ^= (std::size_t) (positive >> i) + (seed<<6) + (seed>>2);
} }
seed ^= (size_t) val + (seed<<6) + (seed>>2); seed ^= (std::size_t) val + (seed<<6) + (seed>>2);
return seed; return seed;
} }
template <class T> template <class T>
inline size_t hash_value_unsigned(T val) inline std::size_t hash_value_unsigned(T val)
{ {
const int size_t_bits = std::numeric_limits<size_t>::digits; const int size_t_bits = std::numeric_limits<std::size_t>::digits;
// ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1 // ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
const int length = (std::numeric_limits<T>::digits - 1) const int length = (std::numeric_limits<T>::digits - 1)
/ size_t_bits; / size_t_bits;
size_t seed = 0; std::size_t seed = 0;
// Hopefully, this loop can be unrolled. // Hopefully, this loop can be unrolled.
for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits) for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits)
{ {
seed ^= (size_t) (val >> i) + (seed<<6) + (seed>>2); seed ^= (std::size_t) (val >> i) + (seed<<6) + (seed>>2);
} }
seed ^= (size_t) val + (seed<<6) + (seed>>2); seed ^= (std::size_t) val + (seed<<6) + (seed>>2);
return seed; return seed;
} }