link-single.cc

00001 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
00002 /*
00003  *  Main authors:
00004  *     Christian Schulte <schulte@gecode.org>
00005  *
00006  *  Copyright:
00007  *     Christian Schulte, 2007
00008  *
00009  *  Last modified:
00010  *     $Date: 2008-01-31 18:29:16 +0100 (Thu, 31 Jan 2008) $ by $Author: tack $
00011  *     $Revision: 6017 $
00012  *
00013  *  This file is part of Gecode, the generic constraint
00014  *  development environment:
00015  *     http://www.gecode.org
00016  *
00017  *  Permission is hereby granted, free of charge, to any person obtaining
00018  *  a copy of this software and associated documentation files (the
00019  *  "Software"), to deal in the Software without restriction, including
00020  *  without limitation the rights to use, copy, modify, merge, publish,
00021  *  distribute, sublicense, and/or sell copies of the Software, and to
00022  *  permit persons to whom the Software is furnished to do so, subject to
00023  *  the following conditions:
00024  *
00025  *  The above copyright notice and this permission notice shall be
00026  *  included in all copies or substantial portions of the Software.
00027  *
00028  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00029  *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00030  *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00031  *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
00032  *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
00033  *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
00034  *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00035  *
00036  */
00037 
00038 #include "gecode/int/channel.hh"
00039 
00040 namespace Gecode { namespace Int { namespace Channel {
00041 
00042   forceinline
00043   LinkSingle::LinkSingle(Space* home, bool share, LinkSingle& p)
00044     : MixBinaryPropagator<BoolView,PC_BOOL_VAL,IntView,PC_INT_VAL>
00045   (home,share,p) {}
00046 
00047   Actor*
00048   LinkSingle::copy(Space* home, bool share) {
00049     return new (home) LinkSingle(home,share,*this);
00050   }
00051 
00052   PropCost
00053   LinkSingle::cost(ModEventDelta) const {
00054     return PC_UNARY_LO;
00055   }
00056 
00057   Support::Symbol
00058   LinkSingle::ati(void) {
00059     return Support::Symbol("Gecode::Int::Channel::LinkSingle");
00060   }
00061 
00062   Reflection::ActorSpec
00063   LinkSingle::spec(const Space* home, Reflection::VarMap& m) const {
00064     return MixBinaryPropagator<BoolView,PC_BOOL_VAL,IntView,PC_INT_VAL>
00065       ::spec(home, m, ati());
00066   }
00067 
00068   void
00069   LinkSingle::post(Space* home, Reflection::VarMap& vars,
00070                    const Reflection::ActorSpec& spec) {
00071     spec.checkArity(2);
00072     BoolView b(home, vars, spec[0]);
00073     IntView x(home, vars, spec[1]);
00074     (void) new (home) LinkSingle(home, b, x);
00075   }
00076 
00077   ExecStatus
00078   LinkSingle::propagate(Space* home, ModEventDelta) {
00079     if (x0.zero()) {
00080       GECODE_ME_CHECK(x1.eq(home,0));
00081     } else if (x0.one()) {
00082       GECODE_ME_CHECK(x1.eq(home,1));
00083     } else {
00084       assert(x0.none() && x1.assigned());
00085       if (x1.val() == 0) {
00086         GECODE_ME_CHECK(x0.zero_none(home));
00087       } else {
00088         assert(x1.val() == 1);
00089         GECODE_ME_CHECK(x0.one_none(home));
00090       }
00091     }
00092     return ES_SUBSUMED(this,sizeof(*this));
00093   }
00094 
00095 }}}
00096 
00097 // STATISTICS: int-prop