diff options
Diffstat (limited to 'core/hashfuncs.h')
| -rw-r--r-- | core/hashfuncs.h | 42 |
1 files changed, 38 insertions, 4 deletions
diff --git a/core/hashfuncs.h b/core/hashfuncs.h index e9e57d8b42..121d7e8c59 100644 --- a/core/hashfuncs.h +++ b/core/hashfuncs.h @@ -29,7 +29,8 @@ #ifndef HASHFUNCS_H #define HASHFUNCS_H - +#include "math_funcs.h" +#include "math_defs.h" #include "typedefs.h" /** @@ -69,19 +70,52 @@ static inline uint32_t hash_djb2_one_32(uint32_t p_in,uint32_t p_prev=5381) { return ((p_prev<<5)+p_prev)+p_in; } +static inline uint32_t hash_one_uint64(const uint64_t p_int) { + uint64_t v=p_int; + v = (~v) + (v << 18); // v = (v << 18) - v - 1; + v = v ^ (v >> 31); + v = v * 21; // v = (v + (v << 2)) + (v << 4); + v = v ^ (v >> 11); + v = v + (v << 6); + v = v ^ (v >> 22); + return (int) v; +} + static inline uint32_t hash_djb2_one_float(float p_in,uint32_t p_prev=5381) { union { float f; uint32_t i; } u; - // handle -0 case - if (p_in==0.0f) u.f=0.0f; - else u.f=p_in; + // Normalize +/- 0.0 and NaN values so they hash the same. + if (p_in==0.0f) + u.f=0.0; + else if (Math::is_nan(p_in)) + u.f=Math_NAN; + else + u.f=p_in; return ((p_prev<<5)+p_prev)+u.i; } +// Overload for real_t size changes +static inline uint32_t hash_djb2_one_float(double p_in,uint32_t p_prev=5381) { + union { + double d; + uint64_t i; + } u; + + // Normalize +/- 0.0 and NaN values so they hash the same. + if (p_in==0.0f) + u.d=0.0; + else if (Math::is_nan(p_in)) + u.d=Math_NAN; + else + u.d=p_in; + + return ((p_prev<<5)+p_prev) + hash_one_uint64(u.i); +} + template<class T> static inline uint32_t make_uint32_t(T p_in) { |