intfuncs.h

/****************************************************************************
**
**  This file is part of GAP, a system for computational discrete algebra.
**
**  Copyright of GAP belongs to its developers, whose names are too numerous
**  to list here. Please refer to the COPYRIGHT file for details.
**
**  SPDX-License-Identifier: GPL-2.0-or-later
**
**  This file declares some representation nonspecific integer functions
*/

#ifndef GAP_INTFUNCS_H
#define GAP_INTFUNCS_H

#include "common.h"

/* link between Mersenne Twister randim numbers and
   representation specific large integer codes */

UInt4 nextrandMT_int32(UInt4 * mt);

/* High quality and speed hash functions -- not currently used
   elsewhere in the kernel but might be a good idea */

void MurmurHash3_x86_32(const void * key, int len, UInt4 seed, void * out);

void MurmurHash3_x64_128(const void * key,
                         const int    len,
                         const UInt4  seed,
                         void *       out);

// These three functions provide an wrappers around MurmurHash3
// for common use cases.
// In particular, they deal with taking the output of MurmurHash3,
// and transforming it into an Int which fits into a GAP
// immediate integer.
// The 'seed' parameter sets the initial seed of the hash, different
// values (should) produce different hash values.

// Hash a block of memory
Int HASHKEY_MEM_NC(const void * ptr, UInt4 seed, Int read);

// Hash an entire bag
Int HASHKEY_WHOLE_BAG_NC(Obj obj, UInt4 seed);

// Hash a bag starting at position 'skip', reading 'read' bytes.
// Does NOT perform bounds checking
Int HASHKEY_BAG_NC(Obj obj, UInt4 seed, Int skip, int read);

/****************************************************************************
**
*F * * * * * * * * * * * * * initialize module * * * * * * * * * * * * * * *
*/

/****************************************************************************
**
*F  InitInfoInt() . . . . . . . . . . . . . . . . . . table of init functions
*/
StructInitInfo * InitInfoIntFuncs ( void );


#endif // GAP_INTFUNCS_H