SYS_PointerHash.h

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/*
 * PROPRIETARY INFORMATION.  This software is proprietary to
 * Side Effects Software Inc., and is not to be reproduced,
 * transmitted, or disclosed in any way without written permission.
 *
 * NAME:        SYS_PointerHash.h (SYS Library, C++)
 *
 * COMMENTS:
 */

#ifndef __SYS_PointerHash__
#define __SYS_PointerHash__

#include "SYS_API.h"
#include "SYS_Types.h"  // for uint64
#include <stddef.h>     // for size_t

static inline size_t
SYSpointerHash(const void *ptr)
{
    // Simple hash so there are random values in the lower 16 bits
    // We don't need a really sophisticated hash, just something to ensure the
    // bottom bits aren't all zero.
    uint64 v = (uint64)ptr;
    return v ^ (v >> 29);
}

#endif // __SYS_PointerHash__