map_traits.h File Reference

#include <QtCore>

Go to the source code of this file.

Classes
struct	DefaultKeyTraits< T >
struct	DefaultValueTraits< T >

Functions
quint32	avalanche (quint32 h)
quint32	deavalanche (quint32 h)
bool	isPowerOf2 (quint64 v)
quint64	roundUpPowerOf2 (quint64 v)

Function Documentation

avalanche()

quint32 avalanche ( quint32 h )

inline

Definition at line 34 of file map_traits.h.

{
    h ^= h >> 16;
    h *= 0x85ebca6b;
    h ^= h >> 13;
    h *= 0xc2b2ae35;
    h ^= h >> 16;
    return h;
}

deavalanche()

quint32 deavalanche ( quint32 h )

inline

Definition at line 44 of file map_traits.h.

{
    h ^= h >> 16;
    h *= 0x7ed1b41d;
    h ^= (h ^ (h >> 13)) >> 13;
    h *= 0xa5cb9243;
    h ^= h >> 16;
    return h;
}

isPowerOf2()

bool isPowerOf2 ( quint64 v )

inline

Definition at line 29 of file map_traits.h.

{
    return (v & (v - 1)) == 0;
}

References v.

roundUpPowerOf2()

quint64 roundUpPowerOf2 ( quint64 v )

inline

Definition at line 16 of file map_traits.h.

{
    v--;
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    v |= v >> 32;
    v++;
    return v;
}

References v.