ExecStatus
ElementUnion<SView,RView>::propagate(Space& home, const ModEventDelta&) {
Region r(home);
int n = iv.size();
bool loopVar;
do {
loopVar = false;
// Cache the upper bound iterator, as we have to
// modify the upper bound while iterating
LubRanges<RView> x1ub(x1);
Iter::Ranges::Cache<LubRanges<RView> > x1ubc(r,x1ub);
Iter::Ranges::ToValues<Iter::Ranges::Cache<LubRanges<RView> > >
vx1ub(x1ubc);
GlbRanges<RView> x1lb(x1);
Iter::Ranges::Cache<GlbRanges<RView> > x1lbc(r,x1lb);
Iter::Ranges::ToValues<Iter::Ranges::Cache<GlbRanges<RView> > >
vx1(x1lbc);
// In the first iteration, compute in before[i] the union
// of all the upper bounds of the x_i. At the same time,
// exclude inconsistent x_i from x1 and remove them from
// the list, cancel their dependencies.
GLBndSet sofarBefore(home);
LUBndSet selectedInter(home, IntSet (Limits::min,
Limits::max));
GLBndSet* before =
static_cast<GLBndSet*>(r.ralloc(sizeof(GLBndSet)*n));
int j = 0;
int i = 0;
unsigned int maxCard = 0;
unsigned int minCard = Limits::card;
while ( vx1ub() ) {
// Remove vars at indices not in the upper bound
if (iv[i].idx < vx1ub.val()) {
iv[i].view.cancel(home,*this, PC_SET_ANY);
++i;
continue;
}
assert(iv[i].idx == vx1ub.val());
iv[j] = iv[i];
SView candidate = iv[j].view;
int candidateInd = iv[j].idx;
// inter = glb(candidate) & complement(lub(x0))
GlbRanges<SView> candlb(candidate);
LubRanges<SView> x0ub(x0);
Iter::Ranges::Diff<GlbRanges<SView>,
LubRanges<SView> > diff(candlb, x0ub);
bool selectSingleInconsistent = false;
if (x1.cardMax() <= 1) {
GlbRanges<SView> x0lb(x0);
LubRanges<SView> candub(candidate);
Iter::Ranges::Diff<GlbRanges<SView>,
LubRanges<SView> > diff2(x0lb, candub);
selectSingleInconsistent = diff2() || candidate.cardMax() < x0.cardMin();
}
// exclude inconsistent x_i
// an x_i is inconsistent if
// * at most one x_i can be selected and there are
// elements in x_0 that can't be in x_i
// (selectSingleInconsistent)
// * its min cardinality is greater than maxCard of x0
// * inter is not empty (there are elements in x_i
// that can't be in x_0)
if (selectSingleInconsistent ||
candidate.cardMin() > x0.cardMax() ||
diff()) {
ModEvent me = (x1.exclude(home,candidateInd));
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
iv[j].view.cancel(home,*this, PC_SET_ANY);
++i;
++vx1ub;
continue;
} else {
// if x_i is consistent, check whether we know
// that its index is in x1
if (vx1() && vx1.val()==candidateInd) {
// x0 >= candidate, candidate <= x0
GlbRanges<SView> candlb(candidate);
ModEvent me = x0.includeI(home,candlb);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
LubRanges<SView> x0ub(x0);
me = candidate.intersectI(home,x0ub);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
++vx1;
}
new (&before[j]) GLBndSet(home);
before[j].update(home,sofarBefore);
LubRanges<SView> cub(candidate);
sofarBefore.includeI(home,cub);
GlbRanges<SView> clb(candidate);
selectedInter.intersectI(home,clb);
maxCard = std::max(maxCard, candidate.cardMax());
minCard = std::min(minCard, candidate.cardMin());
}
++vx1ub;
++i; ++j;
}
// cancel the variables with index greater than
// max of lub(x1)
for (int k=i; k<n; k++) {
iv[k].view.cancel(home,*this, PC_SET_ANY);
}
n = j;
iv.size(n);
if (x1.cardMax()==0) {
// Selector is empty, hence the result must be empty
{
GECODE_ME_CHECK(x0.cardMax(home,0));
}
for (int i=n; i--;)
before[i].dispose(home);
return home.ES_SUBSUMED(*this);
}
if (x1.cardMin() > 0) {
// Selector is not empty, hence the intersection of the
// possibly selected lower bounds is contained in x0
BndSetRanges si(selectedInter);
ModEvent me = x0.includeI(home, si);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
me = x0.cardMin(home, minCard);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
selectedInter.dispose(home);
if (x1.cardMax() <= 1) {
ModEvent me = x0.cardMax(home, maxCard);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
{
// x0 <= sofarBefore
BndSetRanges sfB(sofarBefore);
ModEvent me = x0.intersectI(home,sfB);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
sofarBefore.dispose(home);
GLBndSet sofarAfter(home);
// In the second iteration, this time backwards, compute
// sofarAfter as the union of all lub(x_j) with j>i
for (int i=n; i--;) {
// TODO: check for size of universe here?
// if (sofarAfter.size() == 0) break;
// extra = inter(before[i], sofarAfter) - lub(x0)
BndSetRanges b(before[i]);
BndSetRanges s(sofarAfter);
GlbRanges<SView> x0lb(x0);
Iter::Ranges::Union<BndSetRanges, BndSetRanges> inter(b,s);
Iter::Ranges::Diff<GlbRanges<SView>,
Iter::Ranges::Union<BndSetRanges,BndSetRanges> > diff(x0lb, inter);
if (diff()) {
ModEvent me = (x1.include(home,iv[i].idx));
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
// candidate != extra
me = iv[i].view.includeI(home,diff);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
LubRanges<SView> iviub(iv[i].view);
sofarAfter.includeI(home,iviub);
before[i].dispose(home);
}
sofarAfter.dispose(home);
} while (loopVar);
// Test whether we determined x1 without determining x0
if (x1.assigned() && !x0.assigned()) {
int ubsize = static_cast<int>(x1.lubSize());
if (ubsize > 2) {
assert(ubsize==n);
ViewArray<SView> is(home,ubsize);
for (int i=n; i--;)
is[i]=iv[i].view;
GECODE_REWRITE(*this,(RelOp::UnionN<SView, SView>
::post(home(*this),is,x0)));
} else if (ubsize == 2) {
assert(n==2);
SView a = iv[0].view;
SView b = iv[1].view;
GECODE_REWRITE(*this,(RelOp::Union<SView, SView, SView>
::post(home(*this),a,b,x0)));
} else if (ubsize == 1) {
assert(n==1);
GECODE_REWRITE(*this,(Rel::Eq<SView,SView>::post(home(*this),x0,iv[0].view)));
} else {
GECODE_ME_CHECK(x0.cardMax(home, 0));
return home.ES_SUBSUMED(*this);
}
}
bool allAssigned = true;
for (int i=iv.size(); i--;) {
if (!iv[i].view.assigned()) {
allAssigned = false;
break;
}
}
if (x0.assigned() && x1.assigned() && allAssigned) {
return home.ES_SUBSUMED(*this);
}
return ES_FIX;
}
ExecStatus
ElementUnionConst<SView,RView>::propagate(Space& home, const ModEventDelta&) {
Region r(home);
bool* stillSelected = r.alloc<bool>(n_iv);
bool loopVar;
do {
loopVar = false;
for (int i=n_iv; i--;)
stillSelected[i] = false;
// Cache the upper bound iterator, as we have to
// modify the upper bound while iterating
LubRanges<RView> x1ub(x1);
Iter::Ranges::Cache x1ubc(r,x1ub);
Iter::Ranges::ToValues<Iter::Ranges::Cache>
vx1ub(x1ubc);
GlbRanges<RView> x1lb(x1);
Iter::Ranges::Cache x1lbc(r,x1lb);
Iter::Ranges::ToValues<Iter::Ranges::Cache>
vx1(x1lbc);
// In the first iteration, compute in before[i] the union
// of all the upper bounds of the x_i. At the same time,
// exclude inconsistent x_i from x1.
GLBndSet sofarBefore(home);
LUBndSet selectedInter(home, IntSet (Limits::min,
Limits::max));
GLBndSet* before =
static_cast<GLBndSet*>(r.ralloc(sizeof(GLBndSet)*n_iv));
unsigned int maxCard = 0;
unsigned int minCard = Limits::card;
while (vx1ub()) {
int i = vx1ub.val();
IntSetRanges candCardR(iv[i]);
unsigned int candidateCard = Iter::Ranges::size(candCardR);
IntSetRanges candlb(iv[i]);
LubRanges<SView> x0ub(x0);
Iter::Ranges::Diff<IntSetRanges,
LubRanges<SView> > diff(candlb, x0ub);
bool selectSingleInconsistent = false;
if (x1.cardMax() <= 1) {
GlbRanges<SView> x0lb(x0);
IntSetRanges candub(iv[i]);
Iter::Ranges::Diff<GlbRanges<SView>,
IntSetRanges > diff2(x0lb, candub);
selectSingleInconsistent = diff2() || candidateCard < x0.cardMin();
}
// exclude inconsistent x_i
// an x_i is inconsistent if
// * at most one x_i can be selected and there are
// elements in x_0 that can't be in x_i
// (selectSingleInconsistent)
// * its min cardinality is greater than maxCard of x0
// * inter is not empty (there are elements in x_i
// that can't be in x_0)
if (selectSingleInconsistent ||
candidateCard > x0.cardMax() ||
diff()) {
ModEvent me = (x1.exclude(home,i));
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
} else {
stillSelected[i] = true;
// if x_i is consistent, check whether we know
// that its index is in x1
if (vx1() && vx1.val()==i) {
// x0 >= candidate, candidate <= x0
// GlbRanges<SView> candlb(candidate);
IntSetRanges candlb(iv[i]);
ModEvent me = x0.includeI(home,candlb);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
++vx1;
}
new (&before[i]) GLBndSet(home);
before[i].update(home,sofarBefore);
IntSetRanges cub(iv[i]);
sofarBefore.includeI(home,cub);
IntSetRanges clb(iv[i]);
selectedInter.intersectI(home,clb);
maxCard = std::max(maxCard, candidateCard);
minCard = std::min(minCard, candidateCard);
}
++vx1ub;
}
if (x1.cardMax()==0) {
// Selector is empty, hence the result must be empty
{
GECODE_ME_CHECK(x0.cardMax(home,0));
}
for (int i=n_iv; i--;)
if (stillSelected[i])
before[i].dispose(home);
selectedInter.dispose(home);
sofarBefore.dispose(home);
return home.ES_SUBSUMED(*this);
}
if (x1.cardMin() > 0) {
// Selector is not empty, hence the intersection of the
// possibly selected lower bounds is contained in x0
BndSetRanges si(selectedInter);
ModEvent me = x0.includeI(home, si);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
me = x0.cardMin(home, minCard);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
selectedInter.dispose(home);
if (x1.cardMax() <= 1) {
ModEvent me = x0.cardMax(home, maxCard);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
{
// x0 <= sofarBefore
BndSetRanges sfB(sofarBefore);
ModEvent me = x0.intersectI(home,sfB);
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
}
sofarBefore.dispose(home);
GLBndSet sofarAfter(home);
// In the second iteration, this time backwards, compute
// sofarAfter as the union of all lub(x_j) with j>i
for (int i=n_iv; i--;) {
if (!stillSelected[i])
continue;
BndSetRanges b(before[i]);
BndSetRanges s(sofarAfter);
GlbRanges<SView> x0lb(x0);
Iter::Ranges::Union<BndSetRanges, BndSetRanges> inter(b,s);
Iter::Ranges::Diff<GlbRanges<SView>,
Iter::Ranges::Union<BndSetRanges,BndSetRanges> > diff(x0lb, inter);
if (diff()) {
ModEvent me = (x1.include(home,i));
loopVar |= me_modified(me);
GECODE_ME_CHECK(me);
// candidate != extra
IntSetRanges ivi(iv[i]);
if (!Iter::Ranges::subset(diff, ivi))
GECODE_ME_CHECK(ME_SET_FAILED);
}
IntSetRanges iviub(iv[i]);
sofarAfter.includeI(home,iviub);
before[i].dispose(home);
}
sofarAfter.dispose(home);
} while (loopVar);
if (x1.assigned()) {
assert(x0.assigned());
return home.ES_SUBSUMED(*this);
}
return ES_FIX;
}
