/*--------------------------------------------------------------------*/
/*--- Sets of words, with unique set identifiers.                  ---*/
/*---                                                 hg_wordset.h ---*/
/*--------------------------------------------------------------------*/

/*
   This file is part of Helgrind, a Valgrind tool for detecting errors
   in threaded programs.

   Copyright (C) 2007-2015 OpenWorks LLP
       info@open-works.co.uk

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307, USA.

   The GNU General Public License is contained in the file COPYING.

   Neither the names of the U.S. Department of Energy nor the
   University of California nor the names of its contributors may be
   used to endorse or promote products derived from this software
   without prior written permission.
*/

#ifndef __HG_WORDSET_H
#define __HG_WORDSET_H

//------------------------------------------------------------------//
//---                          WordSet                           ---//
//---                      Public Interface                      ---//
//------------------------------------------------------------------//

typedef  struct _WordSetU  WordSetU;  /* opaque */

typedef  UInt              WordSet;   /* opaque, small int index */

/* Allocate and initialise a WordSetU */
WordSetU* HG_(newWordSetU) ( void* (*alloc_nofail)( const HChar*, SizeT ),
                             const HChar* cc,
                             void  (*dealloc)(void*),
                             Word  cacheSize );

/* Free up the WordSetU. */
void HG_(deleteWordSetU) ( WordSetU* );

/* Get the number of elements in this WordSetU. Note that the dead
   WordSet are included in the WordSetU number of elements. */
UWord HG_(cardinalityWSU) ( WordSetU* );

/* Show performance stats for this WordSetU. */
void HG_(ppWSUstats) ( WordSetU* wsu, const HChar* name );


/* Element-level operations on WordSets.  Note that the WordSet
   numbers given out are 0, 1, 2, 3, etc, and as it happens 0 always
   represents the empty set. */

WordSet HG_(emptyWS)        ( WordSetU* );
WordSet HG_(addToWS)        ( WordSetU*, WordSet, UWord );
WordSet HG_(delFromWS)      ( WordSetU*, WordSet, UWord );
WordSet HG_(unionWS)        ( WordSetU*, WordSet, WordSet );
WordSet HG_(intersectWS)    ( WordSetU*, WordSet, WordSet );
WordSet HG_(minusWS)        ( WordSetU*, WordSet, WordSet );
Bool    HG_(isEmptyWS)      ( WordSetU*, WordSet );
Bool    HG_(isSingletonWS)  ( WordSetU*, WordSet, UWord );
UWord   HG_(anyElementOfWS) ( WordSetU*, WordSet );
UWord   HG_(cardinalityWS)  ( WordSetU*, WordSet );
Bool    HG_(elemWS)         ( WordSetU*, WordSet, UWord );
WordSet HG_(doubletonWS)    ( WordSetU*, UWord, UWord );
WordSet HG_(singletonWS)    ( WordSetU*, UWord );
WordSet HG_(isSubsetOf)     ( WordSetU*, WordSet, WordSet );

Bool    HG_(plausibleWS)    ( WordSetU*, WordSet );


Bool    HG_(saneWS_SLOW)    ( WordSetU*, WordSet );

void    HG_(ppWS)           ( WordSetU*, WordSet );

void    HG_(getPayloadWS)   ( /*OUT*/UWord** words, /*OUT*/UWord* nWords, 
                             WordSetU*, WordSet );

/* HG_(dieWS) indicates WordSet is not used/not referenced anymore,
   and its memory can be reclaimed.
   If ever a WordSet with the same content would be needed again,
   a new WordSet will be reallocated.

   BUG ALERT: !!! Using HG_(dieWS) on a WSU introduces a risk of
   dangling references.  Dangling references can be created by keeping
   a ws after having marked it dead. This ws (just an index in
   reality) will be re-cycled : a newly created wv can get the same
   index. This implies that the wrong wv will be used if the 
   "old" ws has been kept.
   Re-using a "dead" ws will be detected if the index has not been
   re-cycled yet.

   Another possibility of bug is to ask for the payload of a ws, and
   then have this ws marked dead while the payload is still being
   examined. This is a real dangling reference in free or re-allocated
   memory. */
void    HG_(dieWS)          ( WordSetU*, WordSet );



//------------------------------------------------------------------//
//---                        end WordSet                         ---//
//---                      Public Interface                      ---//
//------------------------------------------------------------------//

#endif /* ! __HG_WORDSET_H */

/*--------------------------------------------------------------------*/
/*--- end                                             hg_wordset.h ---*/
/*--------------------------------------------------------------------*/