/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */

/*
 *  Main authors:
 *     Guido Tack <guido.tack@monash.edu>
 */

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include <minizinc/astexception.hh>
#include <minizinc/astiterator.hh>
#include <minizinc/copy.hh>
#include <minizinc/eval_par.hh>
#include <minizinc/flat_exp.hh>
#include <minizinc/flatten.hh>
#include <minizinc/flatten_internal.hh>
#include <minizinc/hash.hh>
#include <minizinc/optimize.hh>
#include <minizinc/output.hh>

#include <unordered_map>
#include <unordered_set>

namespace MiniZinc {

// Create domain constraints. Return true if successful.
bool createExplicitDomainConstraints(EnvI& envi, VarDecl* vd, Expression* domain) {
  std::vector<Call*> calls;
  Location iloc = Location().introduce();

  if (domain->type().isfloat() || domain->type().isfloatset()) {
    FloatSetVal* fsv = eval_floatset(envi, domain);
    if (fsv->size() == 1) {  // Range based
      if (fsv->min() == fsv->max()) {
        calls.push_back(
            new Call(iloc, constants().ids.float_.eq, {vd->id(), FloatLit::a(fsv->min())}));
      } else {
        FloatSetVal* cfsv;
        if (vd->ti()->domain()) {
          cfsv = eval_floatset(envi, vd->ti()->domain());
        } else {
          cfsv = FloatSetVal::a(-FloatVal::infinity(), FloatVal::infinity());
        }
        if (cfsv->min() < fsv->min()) {
          calls.push_back(
              new Call(iloc, constants().ids.float_.le, {FloatLit::a(fsv->min()), vd->id()}));
        }
        if (cfsv->max() > fsv->max()) {
          calls.push_back(
              new Call(iloc, constants().ids.float_.le, {vd->id(), FloatLit::a(fsv->max())}));
        }
      }
    } else {
      calls.push_back(new Call(iloc, constants().ids.set_in, {vd->id(), new SetLit(iloc, fsv)}));
    }
  } else if (domain->type().isint() || domain->type().isintset()) {
    IntSetVal* isv = eval_intset(envi, domain);
    if (isv->size() == 1) {  // Range based
      if (isv->min() == isv->max()) {
        calls.push_back(new Call(iloc, constants().ids.int_.eq, {vd->id(), IntLit::a(isv->min())}));
      } else {
        IntSetVal* cisv;
        if (vd->ti()->domain()) {
          cisv = eval_intset(envi, vd->ti()->domain());
        } else {
          cisv = IntSetVal::a(-IntVal::infinity(), IntVal::infinity());
        }
        if (cisv->min() < isv->min()) {
          calls.push_back(
              new Call(iloc, constants().ids.int_.le, {IntLit::a(isv->min()), vd->id()}));
        }
        if (cisv->max() > isv->max()) {
          calls.push_back(
              new Call(iloc, constants().ids.int_.le, {vd->id(), IntLit::a(isv->max())}));
        }
      }
    } else {
      calls.push_back(new Call(iloc, constants().ids.set_in, {vd->id(), new SetLit(iloc, isv)}));
    }
  } else {
    std::cerr << "Warning: domain change not handled by -g mode: " << *vd->id() << " = " << *domain
              << std::endl;
    return false;
  }

  int counter = 0;
  for (Call* c : calls) {
    CallStackItem csi(envi, IntLit::a(counter++));
    c->ann().add(constants().ann.domain_change_constraint);
    c->type(Type::varbool());
    c->decl(envi.model->matchFn(envi, c, true));
    flat_exp(envi, Ctx(), c, constants().var_true, constants().var_true);
  }
  return true;
}

void setComputedDomain(EnvI& envi, VarDecl* vd, Expression* domain, bool is_computed) {
  if (!envi.fopts.record_domain_changes || vd->ann().contains(constants().ann.is_defined_var) ||
      vd->introduced() || !createExplicitDomainConstraints(envi, vd, domain)) {
    vd->ti()->domain(domain);
    vd->ti()->setComputedDomain(is_computed);
  }
}

/// Output operator for contexts
template <class Char, class Traits>
std::basic_ostream<Char, Traits>& operator<<(std::basic_ostream<Char, Traits>& os, Ctx& ctx) {
  switch (ctx.b) {
    case C_ROOT:
      os << "R";
      break;
    case C_POS:
      os << "+";
      break;
    case C_NEG:
      os << "-";
      break;
    case C_MIX:
      os << "M";
      break;
    default:
      assert(false);
      break;
  }
  switch (ctx.i) {
    case C_ROOT:
      os << "R";
      break;
    case C_POS:
      os << "+";
      break;
    case C_NEG:
      os << "-";
      break;
    case C_MIX:
      os << "M";
      break;
    default:
      assert(false);
      break;
  }
  if (ctx.neg) os << "!";
  return os;
}

BCtx operator+(const BCtx& c) {
  switch (c) {
    case C_ROOT:
      return C_POS;
    case C_POS:
      return C_POS;
    case C_NEG:
      return C_NEG;
    case C_MIX:
      return C_MIX;
    default:
      assert(false);
      return C_ROOT;
  }
}

BCtx operator-(const BCtx& c) {
  switch (c) {
    case C_ROOT:
      return C_NEG;
    case C_POS:
      return C_NEG;
    case C_NEG:
      return C_POS;
    case C_MIX:
      return C_MIX;
    default:
      assert(false);
      return C_ROOT;
  }
}

/// Check if \a c is non-positive
bool nonpos(const BCtx& c) { return c == C_NEG || c == C_MIX; }
/// Check if \a c is non-negative
bool nonneg(const BCtx& c) { return c == C_ROOT || c == C_POS; }

void dumpEEb(const std::vector<EE>& ee) {
  for (unsigned int i = 0; i < ee.size(); i++) std::cerr << *ee[i].b() << "\n";
}
void dumpEEr(const std::vector<EE>& ee) {
  for (unsigned int i = 0; i < ee.size(); i++) std::cerr << *ee[i].r() << "\n";
}

std::tuple<BCtx, bool> ann2Ctx(VarDecl* vd) {
  if (vd->ann().contains(constants().ctx.root)) {
    return std::make_tuple(C_ROOT, true);
  } else if (vd->ann().contains(constants().ctx.mix)) {
    return std::make_tuple(C_MIX, true);
  } else if (vd->ann().contains(constants().ctx.pos)) {
    return std::make_tuple(C_POS, true);
  } else if (vd->ann().contains(constants().ctx.neg)) {
    return std::make_tuple(C_NEG, true);
  } else {
    return std::make_tuple(C_MIX, false);
  }
}

void addCtxAnn(VarDecl* vd, BCtx& c) {
  if (vd) {
    Id* ctx_id = NULL;
    BCtx nc;
    bool annotated;
    std::tie(nc, annotated) = ann2Ctx(vd);
    // If previously annotated
    if (annotated) {
      // Early exit
      if (nc == c || nc == C_ROOT || (nc == C_MIX && c != C_ROOT)) {
        return;
      }
      // Remove old annotation
      switch (nc) {
        case C_ROOT:
          vd->ann().remove(constants().ctx.root);
          break;
        case C_MIX:
          vd->ann().remove(constants().ctx.mix);
          break;
        case C_POS:
          vd->ann().remove(constants().ctx.pos);
          break;
        case C_NEG:
          vd->ann().remove(constants().ctx.neg);
          break;
        default:
          assert(false);
          break;
      }
      // Determine new context
      if (c == C_ROOT) {
        nc = C_ROOT;
      } else {
        nc = C_MIX;
      }
    } else {
      nc = c;
    }
    switch (nc) {
      case C_ROOT:
        ctx_id = constants().ctx.root;
        break;
      case C_POS:
        ctx_id = constants().ctx.pos;
        break;
      case C_NEG:
        ctx_id = constants().ctx.neg;
        break;
      case C_MIX:
        ctx_id = constants().ctx.mix;
        break;
      default:
        assert(false);
        break;
    }
    vd->addAnnotation(ctx_id);
  }
}

void makeDefinedVar(VarDecl* vd, Call* c) {
  if (!vd->ann().contains(constants().ann.is_defined_var)) {
    std::vector<Expression*> args(1);
    args[0] = vd->id();
    Call* dv = new Call(Location().introduce(), constants().ann.defines_var, args);
    dv->type(Type::ann());
    vd->addAnnotation(constants().ann.is_defined_var);
    c->addAnnotation(dv);
  }
}

bool isDefinesVarAnn(Expression* e) {
  return e->isa<Call>() && e->cast<Call>()->id() == constants().ann.defines_var;
}

/// Check if \a e is NULL or true
bool istrue(EnvI& env, Expression* e) {
  GCLock lock;
  return e == NULL || (e->type().ispar() && e->type().isbool() && eval_bool(env, e));
}
/// Check if \a e is non-NULL and false
bool isfalse(EnvI& env, Expression* e) {
  GCLock lock;
  return e != NULL && e->type().ispar() && e->type().isbool() && !eval_bool(env, e);
}

EE flat_exp(EnvI& env, Ctx ctx, Expression* e, VarDecl* r, VarDecl* b);
KeepAlive bind(EnvI& env, Ctx ctx, VarDecl* vd, Expression* e);

/// Use bounds from ovd for vd if they are better.
/// Returns true if ovd's bounds are better.
bool updateBounds(EnvI& envi, VarDecl* ovd, VarDecl* vd) {
  bool tighter = false;
  bool fixed = false;
  if (ovd->ti()->domain() || ovd->e()) {
    IntVal intval;
    FloatVal doubleval;
    bool boolval;

    if (vd->type().isint()) {
      IntBounds oldbounds = compute_int_bounds(envi, ovd->id());
      IntBounds bounds(0, 0, false);
      if (vd->ti()->domain() || vd->e()) bounds = compute_int_bounds(envi, vd->id());

      if ((vd->ti()->domain() || vd->e()) && bounds.valid && bounds.l.isFinite() &&
          bounds.u.isFinite()) {
        if (oldbounds.valid && oldbounds.l.isFinite() && oldbounds.u.isFinite()) {
          fixed = oldbounds.u == oldbounds.l || bounds.u == bounds.l;
          if (fixed) {
            tighter = true;
            intval = oldbounds.u == oldbounds.l ? oldbounds.u : bounds.l;
            ovd->ti()->domain(new SetLit(ovd->loc(), IntSetVal::a(intval, intval)));
          } else {
            IntSetVal* olddom = ovd->ti()->domain() ? eval_intset(envi, ovd->ti()->domain()) : NULL;
            IntSetVal* newdom = vd->ti()->domain() ? eval_intset(envi, vd->ti()->domain()) : NULL;

            if (olddom) {
              if (!newdom) {
                tighter = true;
              } else {
                IntSetRanges oisr(olddom);
                IntSetRanges nisr(newdom);
                IntSetRanges nisr_card(newdom);

                Ranges::Inter<IntVal, IntSetRanges, IntSetRanges> inter(oisr, nisr);

                if (Ranges::cardinality(inter) < Ranges::cardinality(nisr_card)) {
                  IntSetRanges oisr_inter(olddom);
                  IntSetRanges nisr_inter(newdom);
                  Ranges::Inter<IntVal, IntSetRanges, IntSetRanges> inter_card(oisr_inter,
                                                                               nisr_inter);
                  tighter = true;
                  ovd->ti()->domain(new SetLit(ovd->loc(), IntSetVal::ai(inter_card)));
                }
              }
            }
          }
        }
      } else {
        if (oldbounds.valid && oldbounds.l.isFinite() && oldbounds.u.isFinite()) {
          tighter = true;
          fixed = oldbounds.u == oldbounds.l;
          if (fixed) {
            intval = oldbounds.u;
            ovd->ti()->domain(new SetLit(ovd->loc(), IntSetVal::a(intval, intval)));
          }
        }
      }
    } else if (vd->type().isfloat()) {
      FloatBounds oldbounds = compute_float_bounds(envi, ovd->id());
      FloatBounds bounds(0.0, 0.0, false);
      if (vd->ti()->domain() || vd->e()) bounds = compute_float_bounds(envi, vd->id());
      if ((vd->ti()->domain() || vd->e()) && bounds.valid) {
        if (oldbounds.valid) {
          fixed = oldbounds.u == oldbounds.l || bounds.u == bounds.l;
          if (fixed) doubleval = oldbounds.u == oldbounds.l ? oldbounds.u : bounds.l;
          tighter = fixed || (oldbounds.u - oldbounds.l < bounds.u - bounds.l);
        }
      } else {
        if (oldbounds.valid) {
          tighter = true;
          fixed = oldbounds.u == oldbounds.l;
          if (fixed) doubleval = oldbounds.u;
        }
      }
    } else if (vd->type().isbool()) {
      if (ovd->ti()->domain()) {
        fixed = tighter = true;
        boolval = eval_bool(envi, ovd->ti()->domain());
      } else {
        fixed = tighter = (ovd->e() && ovd->e()->isa<BoolLit>());
        if (fixed) boolval = ovd->e()->cast<BoolLit>()->v();
      }
    }

    if (tighter) {
      vd->ti()->domain(ovd->ti()->domain());
      if (vd->e() == NULL && fixed) {
        if (vd->ti()->type().isvarint()) {
          vd->type(Type::parint());
          vd->ti(new TypeInst(vd->loc(), Type::parint()));
          vd->e(IntLit::a(intval));
        } else if (vd->ti()->type().isvarfloat()) {
          vd->type(Type::parfloat());
          vd->ti(new TypeInst(vd->loc(), Type::parfloat()));
          vd->e(FloatLit::a(doubleval));
        } else if (vd->ti()->type().isvarbool()) {
          vd->type(Type::parbool());
          vd->ti(new TypeInst(vd->loc(), Type::parbool()));
          vd->ti()->domain(boolval ? constants().lit_true : constants().lit_false);
          vd->e(new BoolLit(vd->loc(), boolval));
        }
      }
    }
  }

  return tighter;
}

std::string getPath(EnvI& env) {
  std::string path;
  std::stringstream ss;
  if (env.dumpPath(ss)) path = ss.str();

  return path;
}

inline Location getLoc(EnvI& env, Expression* e1, Expression* e2) {
  if (e1) {
    return e1->loc().introduce();
  } else if (e2) {
    return e2->loc().introduce();
  } else {
    return Location().introduce();
  }
}
inline Id* getId(EnvI& env, Id* origId) {
  return origId ? origId : new Id(Location().introduce(), env.genId(), NULL);
}

StringLit* getLongestMznPathAnnotation(EnvI& env, const Expression* e) {
  StringLit* sl = NULL;

  if (const VarDecl* vd = e->dyn_cast<const VarDecl>()) {
    EnvI::ReversePathMap& reversePathMap = env.getReversePathMap();
    KeepAlive vd_decl_ka(vd->id()->decl());
    EnvI::ReversePathMap::iterator it = reversePathMap.find(vd_decl_ka);
    if (it != reversePathMap.end()) {
      sl = new StringLit(Location(), it->second);
    }
  } else {
    for (ExpressionSetIter it = e->ann().begin(); it != e->ann().end(); ++it) {
      if (Call* ca = (*it)->dyn_cast<Call>()) {
        if (ca->id() == constants().ann.mzn_path) {
          StringLit* sl1 = ca->arg(0)->cast<StringLit>();
          if (sl) {
            if (sl1->v().size() > sl->v().size()) sl = sl1;
          } else {
            sl = sl1;
          }
        }
      }
    }
  }
  return sl;
}

void addPathAnnotation(EnvI& env, Expression* e) {
  if (!(e->type().isann() || e->isa<Id>()) && e->type().dim() == 0) {
    GCLock lock;
    Annotation& ann = e->ann();
    if (ann.containsCall(constants().ann.mzn_path)) return;

    EnvI::ReversePathMap& reversePathMap = env.getReversePathMap();

    std::vector<Expression*> path_args(1);
    std::string p;
    KeepAlive e_ka(e);
    EnvI::ReversePathMap::iterator it = reversePathMap.find(e_ka);
    if (it == reversePathMap.end()) {
      p = getPath(env);
    } else {
      p = it->second;
    }

    if (p.size() != 0) {
      path_args[0] = new StringLit(Location(), p);
      Call* path_call = new Call(e->loc(), constants().ann.mzn_path, path_args);
      path_call->type(Type::ann());
      e->addAnnotation(path_call);
    }
  }
}

VarDecl* newVarDecl(EnvI& env, Ctx ctx, TypeInst* ti, Id* origId, VarDecl* origVd,
                    Expression* rhs) {
  VarDecl* vd = nullptr;

  // Is this vardecl already in the FlatZinc (for unification)
  bool hasBeenAdded = false;

  // Don't use paths for arrays or annotations
  if (ti->type().dim() == 0 && !ti->type().isann()) {
    std::string path = getPath(env);
    if (!path.empty()) {
      EnvI::ReversePathMap& reversePathMap = env.getReversePathMap();
      EnvI::PathMap& pathMap = env.getPathMap();
      EnvI::PathMap::iterator it = pathMap.find(path);

      if (it != pathMap.end()) {
        VarDecl* ovd = Expression::cast<VarDecl>((it->second.decl)());
        unsigned int ovd_pass = it->second.pass_no;

        if (ovd) {
          // If ovd was introduced during the same pass, we can unify
          if (env.current_pass_no == ovd_pass) {
            vd = ovd;
            if (origId) origId->decl(vd);
            hasBeenAdded = true;
          } else {
            vd = new VarDecl(getLoc(env, origVd, rhs), ti, getId(env, origId));
            hasBeenAdded = false;
            updateBounds(env, ovd, vd);
          }

          // Check whether ovd was unified in a previous pass
          if (ovd->id() != ovd->id()->decl()->id()) {
            // We may not have seen the pointed to decl just yet
            KeepAlive ovd_decl_ka(ovd->id()->decl());
            EnvI::ReversePathMap::iterator path2It = reversePathMap.find(ovd_decl_ka);
            if (path2It != reversePathMap.end()) {
              std::string path2 = path2It->second;
              EnvI::PathVar vd_tup{vd, env.current_pass_no};

              pathMap[path] = vd_tup;
              pathMap[path2] = vd_tup;
              KeepAlive vd_ka(vd);
              reversePathMap.insert(vd_ka, path);
            }
          }
        }
      } else {
        // Create new VarDecl and add it to the maps
        vd = new VarDecl(getLoc(env, origVd, rhs), ti, getId(env, origId));
        hasBeenAdded = false;
        EnvI::PathVar vd_tup{vd, env.current_pass_no};
        pathMap[path] = vd_tup;
        KeepAlive vd_ka(vd);
        reversePathMap.insert(vd_ka, path);
      }
    }
  }
  if (vd == nullptr) {
    vd = new VarDecl(getLoc(env, origVd, rhs), ti, getId(env, origId));
    hasBeenAdded = false;
  }

  // If vd has an e() use bind to turn rhs into a constraint
  if (vd->e()) {
    if (rhs) {
      bind(env, ctx, vd, rhs);
    }
  } else {
    vd->e(rhs);
  }
  assert(!vd->type().isbot());
  if (origVd && (origVd->id()->idn() != -1 || origVd->toplevel())) {
    vd->introduced(origVd->introduced());
  } else {
    vd->introduced(true);
  }

  vd->flat(vd);

  // Copy annotations from origVd
  if (origVd) {
    for (ExpressionSetIter it = origVd->ann().begin(); it != origVd->ann().end(); ++it) {
      EE ee_ann = flat_exp(env, Ctx(), *it, NULL, constants().var_true);
      vd->addAnnotation(ee_ann.r());
    }
  }

  if (!hasBeenAdded) {
    if (FunctionI* fi = env.model->matchRevMap(env, vd->type())) {
      // We need to introduce a reverse mapper
      Call* revmap = new Call(Location().introduce(), fi->id(), {vd->id()});
      revmap->decl(fi);
      revmap->type(Type::varbool());
      env.flat_addItem(new ConstraintI(Location().introduce(), revmap));
    }

    VarDeclI* ni = new VarDeclI(Location().introduce(), vd);
    env.flat_addItem(ni);
    EE ee(vd, NULL);
    env.cse_map_insert(vd->id(), ee);
  }

  return vd;
}

#define MZN_FILL_REIFY_MAP(T, ID) \
  reifyMap.insert(                \
      std::pair<ASTString, ASTString>(constants().ids.T.ID, constants().ids.T##reif.ID));

EnvI::EnvI(Model* model0, std::ostream& outstream0, std::ostream& errstream0)
    : model(model0),
      orig_model(NULL),
      output(new Model),
      outstream(outstream0),
      errstream(errstream0),
      current_pass_no(0),
      final_pass_no(1),
      maxPathDepth(0),
      ignorePartial(false),
      ignoreUnknownIds(false),
      maxCallStack(0),
      collect_vardecls(false),
      in_redundant_constraint(0),
      in_maybe_partial(0),
      in_reverse_map_var(false),
      n_reif_ct(0),
      n_imp_ct(0),
      n_imp_del(0),
      n_lin_del(0),
      pathUse(0),
      _flat(new Model),
      _failed(false),
      ids(0) {
  MZN_FILL_REIFY_MAP(int_, lin_eq);
  MZN_FILL_REIFY_MAP(int_, lin_le);
  MZN_FILL_REIFY_MAP(int_, lin_ne);
  MZN_FILL_REIFY_MAP(int_, plus);
  MZN_FILL_REIFY_MAP(int_, minus);
  MZN_FILL_REIFY_MAP(int_, times);
  MZN_FILL_REIFY_MAP(int_, div);
  MZN_FILL_REIFY_MAP(int_, mod);
  MZN_FILL_REIFY_MAP(int_, lt);
  MZN_FILL_REIFY_MAP(int_, le);
  MZN_FILL_REIFY_MAP(int_, gt);
  MZN_FILL_REIFY_MAP(int_, ge);
  MZN_FILL_REIFY_MAP(int_, eq);
  MZN_FILL_REIFY_MAP(int_, ne);
  MZN_FILL_REIFY_MAP(float_, lin_eq);
  MZN_FILL_REIFY_MAP(float_, lin_le);
  MZN_FILL_REIFY_MAP(float_, lin_lt);
  MZN_FILL_REIFY_MAP(float_, lin_ne);
  MZN_FILL_REIFY_MAP(float_, plus);
  MZN_FILL_REIFY_MAP(float_, minus);
  MZN_FILL_REIFY_MAP(float_, times);
  MZN_FILL_REIFY_MAP(float_, div);
  MZN_FILL_REIFY_MAP(float_, mod);
  MZN_FILL_REIFY_MAP(float_, lt);
  MZN_FILL_REIFY_MAP(float_, le);
  MZN_FILL_REIFY_MAP(float_, gt);
  MZN_FILL_REIFY_MAP(float_, ge);
  MZN_FILL_REIFY_MAP(float_, eq);
  MZN_FILL_REIFY_MAP(float_, ne);
  reifyMap.insert(
      std::pair<ASTString, ASTString>(constants().ids.forall, constants().ids.forall_reif));
  reifyMap.insert(
      std::pair<ASTString, ASTString>(constants().ids.bool_eq, constants().ids.bool_eq_reif));
  reifyMap.insert(std::pair<ASTString, ASTString>(constants().ids.bool_clause,
                                                  constants().ids.bool_clause_reif));
  reifyMap.insert(
      std::pair<ASTString, ASTString>(constants().ids.clause, constants().ids.bool_clause_reif));
}
EnvI::~EnvI(void) {
  delete _flat;
  delete output;
  delete model;
  delete orig_model;
}
long long int EnvI::genId(void) { return ids++; }
void EnvI::cse_map_insert(Expression* e, const EE& ee) {
  KeepAlive ka(e);
  cse_map.insert(ka, WW(ee.r(), ee.b()));
}
EnvI::CSEMap::iterator EnvI::cse_map_find(Expression* e) {
  KeepAlive ka(e);
  CSEMap::iterator it = cse_map.find(ka);
  if (it != cse_map.end()) {
    if (it->second.r()) {
      if (it->second.r()->isa<Id>()) {
        int idx = vo.find(it->second.r()->cast<Id>()->decl());
        if (idx == -1 || (*_flat)[idx]->removed()) return cse_map.end();
      }
    } else {
      return cse_map.end();
    }
  }
  return it;
}
void EnvI::cse_map_remove(Expression* e) {
  KeepAlive ka(e);
  cse_map.remove(ka);
}
EnvI::CSEMap::iterator EnvI::cse_map_end(void) { return cse_map.end(); }
void EnvI::dump(void) {
  struct EED {
    static std::string k(Expression* e) {
      std::ostringstream oss;
      oss << *e;
      return oss.str();
    }
    static std::string d(const WW& ee) {
      std::ostringstream oss;
      oss << *ee.r() << " " << ee.b();
      return oss.str();
    }
  };
  cse_map.dump<EED>();
}

void EnvI::flat_addItem(Item* i) {
  assert(_flat);
  if (_failed) return;
  _flat->addItem(i);

  Expression* toAnnotate = NULL;
  Expression* toAdd = NULL;
  switch (i->iid()) {
    case Item::II_VD: {
      VarDeclI* vd = i->cast<VarDeclI>();
      addPathAnnotation(*this, vd->e());
      toAnnotate = vd->e()->e();
      vo.add_idx(vd, _flat->size() - 1);
      toAdd = vd->e();
      break;
    }
    case Item::II_CON: {
      ConstraintI* ci = i->cast<ConstraintI>();

      if (ci->e()->isa<BoolLit>() && !ci->e()->cast<BoolLit>()->v()) {
        fail();
      } else {
        toAnnotate = ci->e();
        addPathAnnotation(*this, ci->e());
        toAdd = ci->e();
      }
      break;
    }
    case Item::II_SOL: {
      SolveI* si = i->cast<SolveI>();
      CollectOccurrencesE ce(vo, si);
      topDown(ce, si->e());
      for (ExpressionSetIter it = si->ann().begin(); it != si->ann().end(); ++it) topDown(ce, *it);
      break;
    }
    case Item::II_OUT: {
      OutputI* si = i->cast<OutputI>();
      toAdd = si->e();
      break;
    }
    default:
      break;
  }
  if (toAnnotate && toAnnotate->isa<Call>()) {
    annotateFromCallStack(toAnnotate);
  }
  if (toAdd) {
    CollectOccurrencesE ce(vo, i);
    topDown(ce, toAdd);
  }
}

void EnvI::annotateFromCallStack(Expression* e) {
  int prev = idStack.size() > 0 ? idStack.back() : 0;
  bool allCalls = true;
  for (int i = static_cast<int>(callStack.size()) - 1; i >= prev; i--) {
    Expression* ee = callStack[i]->untag();
    allCalls = allCalls && (i == callStack.size() - 1 || ee->isa<Call>());
    for (ExpressionSetIter it = ee->ann().begin(); it != ee->ann().end(); ++it) {
      EE ee_ann = flat_exp(*this, Ctx(), *it, NULL, constants().var_true);
      if (allCalls || !isDefinesVarAnn(ee_ann.r())) e->addAnnotation(ee_ann.r());
    }
  }
}

void EnvI::copyPathMapsAndState(EnvI& env) {
  final_pass_no = env.final_pass_no;
  maxPathDepth = env.maxPathDepth;
  current_pass_no = env.current_pass_no;
  filenameMap = env.filenameMap;
  maxPathDepth = env.maxPathDepth;
  pathMap = env.getPathMap();
  reversePathMap = env.getReversePathMap();
}

void EnvI::flat_removeItem(MiniZinc::Item* i) { i->remove(); }
void EnvI::flat_removeItem(int i) { flat_removeItem((*_flat)[i]); }

void EnvI::fail(const std::string& msg) {
  if (!_failed) {
    addWarning(std::string("model inconsistency detected") +
               (msg.empty() ? std::string() : (": " + msg)));
    _failed = true;
    for (unsigned int i = 0; i < _flat->size(); i++) {
      (*_flat)[i]->remove();
    }
    ConstraintI* failedConstraint = new ConstraintI(Location().introduce(), constants().lit_false);
    _flat->addItem(failedConstraint);
    _flat->addItem(SolveI::sat(Location().introduce()));
    for (unsigned int i = 0; i < output->size(); i++) {
      (*output)[i]->remove();
    }
    output->addItem(
        new OutputI(Location().introduce(), new ArrayLit(Location(), std::vector<Expression*>())));
    throw ModelInconsistent(*this, Location().introduce());
  }
}

bool EnvI::failed() const { return _failed; }

unsigned int EnvI::registerEnum(VarDeclI* vdi) {
  EnumMap::iterator it = enumMap.find(vdi);
  unsigned int ret;
  if (it == enumMap.end()) {
    ret = static_cast<unsigned int>(enumVarDecls.size());
    enumVarDecls.push_back(vdi);
    enumMap.insert(std::make_pair(vdi, ret));
  } else {
    ret = it->second;
  }
  return ret + 1;
}
VarDeclI* EnvI::getEnum(unsigned int i) const {
  assert(i > 0 && i <= enumVarDecls.size());
  return enumVarDecls[i - 1];
}
unsigned int EnvI::registerArrayEnum(const std::vector<unsigned int>& arrayEnum) {
  std::ostringstream oss;
  for (unsigned int i = 0; i < arrayEnum.size(); i++) {
    assert(arrayEnum[i] <= enumVarDecls.size());
    oss << arrayEnum[i] << ".";
  }
  ArrayEnumMap::iterator it = arrayEnumMap.find(oss.str());
  unsigned int ret;
  if (it == arrayEnumMap.end()) {
    ret = static_cast<unsigned int>(arrayEnumDecls.size());
    arrayEnumDecls.push_back(arrayEnum);
    arrayEnumMap.insert(std::make_pair(oss.str(), ret));
  } else {
    ret = it->second;
  }
  return ret + 1;
}
const std::vector<unsigned int>& EnvI::getArrayEnum(unsigned int i) const {
  assert(i > 0 && i <= arrayEnumDecls.size());
  return arrayEnumDecls[i - 1];
}
bool EnvI::isSubtype(const Type& t1, const Type& t2, bool strictEnums) {
  if (!t1.isSubtypeOf(t2, strictEnums)) return false;
  if (strictEnums && t1.dim() == 0 && t2.dim() != 0 && t2.enumId() != 0) {
    // set assigned to an array
    const std::vector<unsigned int>& t2enumIds = getArrayEnum(t2.enumId());
    if (t2enumIds[t2enumIds.size() - 1] != 0 && t1.enumId() != t2enumIds[t2enumIds.size() - 1])
      return false;
  }
  if (strictEnums && t1.dim() > 0 && t1.enumId() != t2.enumId()) {
    if (t1.enumId() == 0) {
      return t1.isbot();
    }
    if (t2.enumId() != 0) {
      const std::vector<unsigned int>& t1enumIds = getArrayEnum(t1.enumId());
      const std::vector<unsigned int>& t2enumIds = getArrayEnum(t2.enumId());
      assert(t1enumIds.size() == t2enumIds.size());
      for (unsigned int i = 0; i < t1enumIds.size() - 1; i++) {
        if (t2enumIds[i] != 0 && t1enumIds[i] != t2enumIds[i]) return false;
      }
      if (!t1.isbot() && t2enumIds[t1enumIds.size() - 1] != 0 &&
          t1enumIds[t1enumIds.size() - 1] != t2enumIds[t2enumIds.size() - 1])
        return false;
    }
  }
  return true;
}

void EnvI::collectVarDecls(bool b) { collect_vardecls = b; }
void EnvI::vo_add_exp(VarDecl* vd) {
  if (vd->e() && vd->e()->isa<Call>() && !vd->e()->type().isann()) {
    int prev = idStack.size() > 0 ? idStack.back() : 0;
    for (int i = static_cast<int>(callStack.size()) - 1; i >= prev; i--) {
      Expression* ee = callStack[i]->untag();
      for (ExpressionSetIter it = ee->ann().begin(); it != ee->ann().end(); ++it) {
        Expression* ann = *it;
        if (ann != constants().ann.add_to_output && ann != constants().ann.rhs_from_assignment) {
          bool needAnnotation = true;
          if (Call* ann_c = ann->dyn_cast<Call>()) {
            if (ann_c->id() == constants().ann.defines_var) {
              // only add defines_var annotation if vd is the defined variable
              if (Id* defined_var = ann_c->arg(0)->dyn_cast<Id>()) {
                if (defined_var->decl() != vd->id()->decl()) {
                  needAnnotation = false;
                }
              }
            }
          }
          if (needAnnotation) {
            EE ee_ann = flat_exp(*this, Ctx(), *it, NULL, constants().var_true);
            vd->e()->addAnnotation(ee_ann.r());
          }
        }
      }
    }
  }
  int idx = vo.find(vd);
  CollectOccurrencesE ce(vo, (*_flat)[idx]);
  topDown(ce, vd->e());
  if (collect_vardecls) modifiedVarDecls.push_back(idx);
}
Model* EnvI::flat(void) { return _flat; }
void EnvI::swap() {
  Model* tmp = model;
  model = _flat;
  _flat = tmp;
}
ASTString EnvI::reifyId(const ASTString& id) {
  ASTStringMap<ASTString>::t::iterator it = reifyMap.find(id);
  if (it == reifyMap.end()) {
    return id.str() + "_reif";
  } else {
    return it->second;
  }
}
#undef MZN_FILL_REIFY_MAP
ASTString EnvI::halfReifyId(const ASTString& id) { return id.str() + "_imp"; }

void EnvI::addWarning(const std::string& msg) {
  if (warnings.size() > 20) return;
  if (warnings.size() == 20) {
    warnings.push_back("Further warnings have been suppressed.\n");
  } else {
    std::ostringstream oss;
    createErrorStack();
    dumpStack(oss, true);
    warnings.push_back(msg + "\n" + oss.str());
  }
}

void EnvI::createErrorStack(void) {
  errorStack.clear();
  for (unsigned int i = static_cast<unsigned int>(callStack.size()); i--;) {
    Expression* e = callStack[i]->untag();
    bool isCompIter = callStack[i]->isTagged();
    KeepAlive ka(e);
    errorStack.push_back(std::make_pair(ka, isCompIter));
  }
}

Call* EnvI::surroundingCall(void) const {
  if (callStack.size() >= 2) return callStack[callStack.size() - 2]->untag()->dyn_cast<Call>();
  return NULL;
}

void EnvI::cleanupExceptOutput() {
  cmap.clear();
  cse_map.clear();
  delete _flat;
  delete model;
  delete orig_model;
  _flat = 0;
  model = 0;
}

CallStackItem::CallStackItem(EnvI& env0, Expression* e) : env(env0) {
  if (e->isa<VarDecl>()) env.idStack.push_back(static_cast<int>(env.callStack.size()));
  if (e->isa<Call>() && e->cast<Call>()->id() == "redundant_constraint")
    env.in_redundant_constraint++;
  if (e->ann().contains(constants().ann.maybe_partial)) env.in_maybe_partial++;
  env.callStack.push_back(e);
  env.maxCallStack = std::max(env.maxCallStack, static_cast<unsigned int>(env.callStack.size()));
}
CallStackItem::CallStackItem(EnvI& env0, Id* ident, IntVal i) : env(env0) {
  Expression* ee = ident->tag();
  env.callStack.push_back(ee);
  env.maxCallStack = std::max(env.maxCallStack, static_cast<unsigned int>(env.callStack.size()));
}
CallStackItem::~CallStackItem(void) {
  Expression* e = env.callStack.back()->untag();
  if (e->isa<VarDecl>()) env.idStack.pop_back();
  if (e->isa<Call>() && e->cast<Call>()->id() == "redundant_constraint")
    env.in_redundant_constraint--;
  if (e->ann().contains(constants().ann.maybe_partial)) env.in_maybe_partial--;
  env.callStack.pop_back();
}

FlatteningError::FlatteningError(EnvI& env, const Location& loc, const std::string& msg)
    : LocationException(env, loc, msg) {}

Env::Env(Model* m, std::ostream& outstream, std::ostream& errstream)
    : e(new EnvI(m, outstream, errstream)) {}
Env::~Env(void) { delete e; }

Model* Env::model(void) { return e->model; }
void Env::model(Model* m) { e->model = m; }
Model* Env::flat(void) { return e->flat(); }
void Env::swap() { e->swap(); }
Model* Env::output(void) { return e->output; }

std::ostream& Env::evalOutput(std::ostream& os) { return e->evalOutput(os); }
EnvI& Env::envi(void) { return *e; }
const EnvI& Env::envi(void) const { return *e; }
std::ostream& Env::dumpErrorStack(std::ostream& os) { return e->dumpStack(os, true); }

bool EnvI::dumpPath(std::ostream& os, bool force) {
  force = force ? force : fopts.collect_mzn_paths;
  if (callStack.size() > maxPathDepth) {
    if (!force && current_pass_no >= final_pass_no - 1) {
      return false;
    }
    maxPathDepth = static_cast<int>(callStack.size());
  }

  unsigned int lastError = static_cast<unsigned int>(callStack.size());

  std::string major_sep = ";";
  std::string minor_sep = "|";
  for (unsigned int i = 0; i < lastError; i++) {
    Expression* e = callStack[i]->untag();
    bool isCompIter = callStack[i]->isTagged();
    Location loc = e->loc();
    int filenameId;
    std::unordered_map<std::string, int>::iterator findFilename =
        filenameMap.find(loc.filename().str());
    if (findFilename == filenameMap.end()) {
      if (!force && current_pass_no >= final_pass_no - 1) return false;
      filenameId = static_cast<int>(filenameMap.size());
      filenameMap.insert(
          std::make_pair(loc.filename().str(), static_cast<int>(filenameMap.size())));
    } else {
      filenameId = findFilename->second;
    }

    // If this call is not a dummy StringLit with empty Location (so that deferred compilation
    // doesn't drop the paths)
    if (e->eid() != Expression::E_STRINGLIT || loc.first_line() || loc.first_column() ||
        loc.last_line() || loc.last_column()) {
      os << loc.filename().str() << minor_sep << loc.first_line() << minor_sep << loc.first_column()
         << minor_sep << loc.last_line() << minor_sep << loc.last_column() << minor_sep;
      switch (e->eid()) {
        case Expression::E_INTLIT:
          os << "il" << minor_sep << *e;
          break;
        case Expression::E_FLOATLIT:
          os << "fl" << minor_sep << *e;
          break;
        case Expression::E_SETLIT:
          os << "sl" << minor_sep << *e;
          break;
        case Expression::E_BOOLLIT:
          os << "bl" << minor_sep << *e;
          break;
        case Expression::E_STRINGLIT:
          os << "stl" << minor_sep << *e;
          break;
        case Expression::E_ID:
          if (isCompIter) {
            // if (e->cast<Id>()->decl()->e()->type().ispar())
            os << *e << "=" << *e->cast<Id>()->decl()->e();
            // else
            //  os << *e << "=?";
          } else {
            os << "id" << minor_sep << *e;
          }
          break;
        case Expression::E_ANON:
          os << "anon";
          break;
        case Expression::E_ARRAYLIT:
          os << "al";
          break;
        case Expression::E_ARRAYACCESS:
          os << "aa";
          break;
        case Expression::E_COMP: {
          const Comprehension* cmp = e->cast<Comprehension>();
          if (cmp->set())
            os << "sc";
          else
            os << "ac";
        } break;
        case Expression::E_ITE:
          os << "ite";
          break;
        case Expression::E_BINOP:
          os << "bin" << minor_sep << e->cast<BinOp>()->opToString();
          break;
        case Expression::E_UNOP:
          os << "un" << minor_sep << e->cast<UnOp>()->opToString();
          break;
        case Expression::E_CALL:
          if (fopts.only_toplevel_paths) return false;
          os << "ca" << minor_sep << e->cast<Call>()->id();
          break;
        case Expression::E_VARDECL:
          os << "vd";
          break;
        case Expression::E_LET:
          os << "l";
          break;
        case Expression::E_TI:
          os << "ti";
          break;
        case Expression::E_TIID:
          os << "ty";
          break;
        default:
          assert(false);
          os << "unknown expression (internal error)";
          break;
      }
      os << major_sep;
    } else {
      os << e->cast<StringLit>()->v() << major_sep;
    }
  }
  return true;
}

std::ostream& EnvI::dumpStack(std::ostream& os, bool errStack) {
  int lastError = 0;

  std::vector<Expression*> errStackCopy;
  if (errStack) {
    errStackCopy.resize(errorStack.size());
    for (unsigned int i = 0; i < errorStack.size(); i++) {
      Expression* e = errorStack[i].first();
      if (errorStack[i].second) {
        e = e->tag();
      }
      errStackCopy[i] = e;
    }
  }

  std::vector<Expression*>& stack = errStack ? errStackCopy : callStack;

  for (; lastError < stack.size(); lastError++) {
    Expression* e = stack[lastError]->untag();
    bool isCompIter = stack[lastError]->isTagged();
    if (e->loc().is_introduced()) continue;
    if (!isCompIter && e->isa<Id>()) {
      break;
    }
  }

  ASTString curloc_f;
  int curloc_l = -1;

  for (int i = lastError - 1; i >= 0; i--) {
    Expression* e = stack[i]->untag();
    bool isCompIter = stack[i]->isTagged();
    ASTString newloc_f = e->loc().filename();
    if (e->loc().is_introduced()) continue;
    int newloc_l = e->loc().first_line();
    if (newloc_f != curloc_f || newloc_l != curloc_l) {
      os << "  " << newloc_f << ":" << newloc_l << ":" << std::endl;
      curloc_f = newloc_f;
      curloc_l = newloc_l;
    }
    if (isCompIter)
      os << "    with ";
    else
      os << "  in ";
    switch (e->eid()) {
      case Expression::E_INTLIT:
        os << "integer literal" << std::endl;
        break;
      case Expression::E_FLOATLIT:
        os << "float literal" << std::endl;
        break;
      case Expression::E_SETLIT:
        os << "set literal" << std::endl;
        break;
      case Expression::E_BOOLLIT:
        os << "bool literal" << std::endl;
        break;
      case Expression::E_STRINGLIT:
        os << "string literal" << std::endl;
        break;
      case Expression::E_ID:
        if (isCompIter) {
          if (e->cast<Id>()->decl()->e()->type().ispar())
            os << *e << " = " << *e->cast<Id>()->decl()->e() << std::endl;
          else
            os << *e << " = <expression>" << std::endl;
        } else {
          os << "identifier" << *e << std::endl;
        }
        break;
      case Expression::E_ANON:
        os << "anonymous variable" << std::endl;
        break;
      case Expression::E_ARRAYLIT:
        os << "array literal" << std::endl;
        break;
      case Expression::E_ARRAYACCESS:
        os << "array access" << std::endl;
        break;
      case Expression::E_COMP: {
        const Comprehension* cmp = e->cast<Comprehension>();
        if (cmp->set())
          os << "set ";
        else
          os << "array ";
        os << "comprehension expression" << std::endl;
      } break;
      case Expression::E_ITE:
        os << "if-then-else expression" << std::endl;
        break;
      case Expression::E_BINOP:
        os << "binary " << e->cast<BinOp>()->opToString() << " operator expression" << std::endl;
        break;
      case Expression::E_UNOP:
        os << "unary " << e->cast<UnOp>()->opToString() << " operator expression" << std::endl;
        break;
      case Expression::E_CALL:
        os << "call '" << e->cast<Call>()->id() << "'" << std::endl;
        break;
      case Expression::E_VARDECL: {
        GCLock lock;
        os << "variable declaration for '" << e->cast<VarDecl>()->id()->str() << "'" << std::endl;
      } break;
      case Expression::E_LET:
        os << "let expression" << std::endl;
        break;
      case Expression::E_TI:
        os << "type-inst expression" << std::endl;
        break;
      case Expression::E_TIID:
        os << "type identifier" << std::endl;
        break;
      default:
        assert(false);
        os << "unknown expression (internal error)" << std::endl;
        break;
    }
  }
  return os;
}

void populateOutput(Env& env) {
  EnvI& envi = env.envi();
  Model* _flat = envi.flat();
  Model* _output = envi.output;
  std::vector<Expression*> outputVars;
  for (VarDeclIterator it = _flat->begin_vardecls(); it != _flat->end_vardecls(); ++it) {
    VarDecl* vd = it->e();
    Annotation& ann = vd->ann();
    ArrayLit* dims = NULL;
    bool has_output_ann = false;
    if (!ann.isEmpty()) {
      for (ExpressionSetIter ait = ann.begin(); ait != ann.end(); ++ait) {
        if (Call* c = (*ait)->dyn_cast<Call>()) {
          if (c->id() == constants().ann.output_array) {
            dims = c->arg(0)->cast<ArrayLit>();
            has_output_ann = true;
            break;
          }
        } else if ((*ait)->isa<Id>() &&
                   (*ait)->cast<Id>()->str() == constants().ann.output_var->str()) {
          has_output_ann = true;
        }
      }
      if (has_output_ann) {
        std::ostringstream s;
        s << vd->id()->str().str() << " = ";

        VarDecl* vd_output = copy(env.envi(), vd)->cast<VarDecl>();
        Type vd_t = vd_output->type();
        vd_t.ti(Type::TI_PAR);
        vd_output->type(vd_t);
        vd_output->ti()->type(vd_t);
        _output->addItem(new VarDeclI(Location().introduce(), vd_output));

        if (dims) {
          s << "array" << dims->size() << "d(";
          for (unsigned int i = 0; i < dims->size(); i++) {
            IntSetVal* idxset = eval_intset(envi, (*dims)[i]);
            s << *idxset << ",";
          }
        }
        StringLit* sl = new StringLit(Location().introduce(), s.str());
        outputVars.push_back(sl);

        std::vector<Expression*> showArgs(1);
        showArgs[0] = vd_output->id();
        Call* show = new Call(Location().introduce(), constants().ids.show, showArgs);
        show->type(Type::parstring());
        FunctionI* fi = _flat->matchFn(envi, show, false);
        assert(fi);
        show->decl(fi);
        outputVars.push_back(show);
        std::string ends = dims ? ")" : "";
        ends += ";\n";
        StringLit* eol = new StringLit(Location().introduce(), ends);
        outputVars.push_back(eol);
      }
    }
  }
  OutputI* newOutputItem =
      new OutputI(Location().introduce(), new ArrayLit(Location().introduce(), outputVars));
  _output->addItem(newOutputItem);
  envi.flat()->mergeStdLib(envi, _output);
}

std::ostream& EnvI::evalOutput(std::ostream& os) {
  GCLock lock;

  ArrayLit* al = eval_array_lit(*this, output->outputItem()->e());
  bool fLastEOL = true;
  for (unsigned int i = 0; i < al->size(); i++) {
    std::string s = eval_string(*this, (*al)[i]);
    if (!s.empty()) {
      os << s;
      fLastEOL = ('\n' == s.back());
    }
  }
  if (!fLastEOL) os << '\n';
  return os;
}

const std::vector<std::string>& Env::warnings(void) { return envi().warnings; }

void Env::clearWarnings(void) { envi().warnings.clear(); }

unsigned int Env::maxCallStack(void) const { return envi().maxCallStack; }

void checkIndexSets(EnvI& env, VarDecl* vd, Expression* e) {
  ASTExprVec<TypeInst> tis = vd->ti()->ranges();
  std::vector<TypeInst*> newtis(tis.size());
  bool needNewTypeInst = false;
  GCLock lock;
  switch (e->eid()) {
    case Expression::E_ID: {
      Id* id = e->cast<Id>();
      ASTExprVec<TypeInst> e_tis = id->decl()->ti()->ranges();
      assert(tis.size() == e_tis.size());
      for (unsigned int i = 0; i < tis.size(); i++) {
        if (tis[i]->domain() == NULL) {
          newtis[i] = e_tis[i];
          needNewTypeInst = true;
        } else {
          if (!eval_intset(env, tis[i]->domain())->equal(eval_intset(env, e_tis[i]->domain())))
            throw EvalError(env, vd->loc(), "Index set mismatch");
          newtis[i] = tis[i];
        }
      }
    } break;
    case Expression::E_ARRAYLIT: {
      ArrayLit* al = e->cast<ArrayLit>();
      for (unsigned int i = 0; i < tis.size(); i++) {
        if (tis[i]->domain() == NULL) {
          newtis[i] = new TypeInst(
              Location().introduce(), Type(),
              new SetLit(Location().introduce(), IntSetVal::a(al->min(i), al->max(i))));
          needNewTypeInst = true;
        } else if (i == 0 || al->size() != 0) {
          IntSetVal* isv = eval_intset(env, tis[i]->domain());
          assert(isv->size() <= 1);
          if ((isv->size() == 0 && al->min(i) <= al->max(i)) ||
              (isv->size() != 0 && (isv->min(0) != al->min(i) || isv->max(0) != al->max(i))))
            throw EvalError(env, vd->loc(), "Index set mismatch");
          newtis[i] = tis[i];
        }
      }
    } break;
    default:
      throw InternalError("not supported yet");
  }
  if (needNewTypeInst) {
    TypeInst* tic = copy(env, vd->ti())->cast<TypeInst>();
    tic->setRanges(newtis);
    vd->ti(tic);
  }
}

/// Turn \a c into domain constraints if possible.
/// Return whether \a c is still required in the model.
bool checkDomainConstraints(EnvI& env, Call* c) {
  if (env.fopts.record_domain_changes) return true;
  if (c->id() == constants().ids.int_.le) {
    Expression* e0 = c->arg(0);
    Expression* e1 = c->arg(1);
    if (e0->type().ispar() && e1->isa<Id>()) {
      // greater than
      Id* id = e1->cast<Id>();
      IntVal lb = eval_int(env, e0);
      if (id->decl()->ti()->domain()) {
        IntSetVal* domain = eval_intset(env, id->decl()->ti()->domain());
        if (domain->min() >= lb) return false;
        if (domain->max() < lb) {
          env.fail();
          return false;
        }
        IntSetRanges dr(domain);
        Ranges::Const<IntVal> cr(lb, IntVal::infinity());
        Ranges::Inter<IntVal, IntSetRanges, Ranges::Const<IntVal> > i(dr, cr);
        IntSetVal* newibv = IntSetVal::ai(i);
        id->decl()->ti()->domain(new SetLit(Location().introduce(), newibv));
        id->decl()->ti()->setComputedDomain(false);
      } else {
        id->decl()->ti()->domain(
            new SetLit(Location().introduce(), IntSetVal::a(lb, IntVal::infinity())));
      }
      return false;
    } else if (e1->type().ispar() && e0->isa<Id>()) {
      // less than
      Id* id = e0->cast<Id>();
      IntVal ub = eval_int(env, e1);
      if (id->decl()->ti()->domain()) {
        IntSetVal* domain = eval_intset(env, id->decl()->ti()->domain());
        if (domain->max() <= ub) return false;
        if (domain->min() > ub) {
          env.fail();
          return false;
        }
        IntSetRanges dr(domain);
        Ranges::Const<IntVal> cr(-IntVal::infinity(), ub);
        Ranges::Inter<IntVal, IntSetRanges, Ranges::Const<IntVal> > i(dr, cr);
        IntSetVal* newibv = IntSetVal::ai(i);
        id->decl()->ti()->domain(new SetLit(Location().introduce(), newibv));
        id->decl()->ti()->setComputedDomain(false);
      } else {
        id->decl()->ti()->domain(
            new SetLit(Location().introduce(), IntSetVal::a(-IntVal::infinity(), ub)));
      }
    }
  } else if (c->id() == constants().ids.int_.lin_le) {
    ArrayLit* al_c = follow_id(c->arg(0))->cast<ArrayLit>();
    if (al_c->size() == 1) {
      ArrayLit* al_x = follow_id(c->arg(1))->cast<ArrayLit>();
      IntVal coeff = eval_int(env, (*al_c)[0]);
      IntVal y = eval_int(env, c->arg(2));
      IntVal lb = -IntVal::infinity();
      IntVal ub = IntVal::infinity();
      IntVal r = y % coeff;
      if (coeff >= 0) {
        ub = y / coeff;
        if (r < 0) --ub;
      } else {
        lb = y / coeff;
        if (r < 0) ++lb;
      }
      if (Id* id = (*al_x)[0]->dyn_cast<Id>()) {
        if (id->decl()->ti()->domain()) {
          IntSetVal* domain = eval_intset(env, id->decl()->ti()->domain());
          if (domain->max() <= ub && domain->min() >= lb) return false;
          if (domain->min() > ub || domain->max() < lb) {
            env.fail();
            return false;
          }
          IntSetRanges dr(domain);
          Ranges::Const<IntVal> cr(lb, ub);
          Ranges::Inter<IntVal, IntSetRanges, Ranges::Const<IntVal> > i(dr, cr);
          IntSetVal* newibv = IntSetVal::ai(i);
          id->decl()->ti()->domain(new SetLit(Location().introduce(), newibv));
          id->decl()->ti()->setComputedDomain(false);
        } else {
          id->decl()->ti()->domain(new SetLit(Location().introduce(), IntSetVal::a(lb, ub)));
        }
        return false;
      }
    }
  }
  return true;
}

KeepAlive bind(EnvI& env, Ctx ctx, VarDecl* vd, Expression* e) {
  assert(e == NULL || !e->isa<VarDecl>());
  if (vd == constants().var_ignore) return e;
  if (Id* ident = e->dyn_cast<Id>()) {
    if (ident->decl()) {
      VarDecl* e_vd = follow_id_to_decl(ident)->cast<VarDecl>();
      e = e_vd->id();
      if (!env.in_reverse_map_var && ctx.b != C_ROOT && e->type() == Type::varbool()) {
        addCtxAnn(e_vd, ctx.b);
        if (e_vd != ident->decl()) {
          addCtxAnn(ident->decl(), ctx.b);
        }
      }
    }
  }
  if (ctx.neg) {
    assert(e->type().bt() == Type::BT_BOOL);
    if (vd == constants().var_true) {
      if (!isfalse(env, e)) {
        if (Id* id = e->dyn_cast<Id>()) {
          while (id != NULL) {
            assert(id->decl() != NULL);
            if (id->decl()->ti()->domain() && istrue(env, id->decl()->ti()->domain())) {
              GCLock lock;
              env.flat_addItem(new ConstraintI(Location().introduce(), constants().lit_false));
            } else {
              id->decl()->ti()->domain(constants().lit_false);
              GCLock lock;
              std::vector<Expression*> args(2);
              args[0] = id;
              args[1] = constants().lit_false;
              Call* c = new Call(Location().introduce(), constants().ids.bool_eq, args);
              c->decl(env.model->matchFn(env, c, false));
              c->type(c->decl()->rtype(env, args, false));
              if (c->decl()->e()) {
                flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
              }
            }
            id = id->decl()->e() ? id->decl()->e()->dyn_cast<Id>() : NULL;
          }
          return constants().lit_true;
        } else {
          GC::lock();
          BinOp* bo = new BinOp(e->loc(), e, BOT_EQUIV, constants().lit_false);
          bo->type(e->type());
          KeepAlive ka(bo);
          GC::unlock();
          EE ee = flat_exp(env, Ctx(), bo, NULL, constants().var_true);
          return bind(env, Ctx(), vd, ee.r());
        }
      }
      return constants().lit_true;
    } else {
      GC::lock();
      BinOp* bo = new BinOp(e->loc(), e, BOT_EQUIV, constants().lit_false);
      bo->type(e->type());
      KeepAlive ka(bo);
      GC::unlock();
      EE ee = flat_exp(env, Ctx(), bo, NULL, constants().var_true);
      return bind(env, Ctx(), vd, ee.r());
    }
  } else {
    if (vd == constants().var_true) {
      if (!istrue(env, e)) {
        if (Id* id = e->dyn_cast<Id>()) {
          assert(id->decl() != NULL);
          while (id != NULL) {
            if (id->decl()->ti()->domain() && isfalse(env, id->decl()->ti()->domain())) {
              GCLock lock;
              env.flat_addItem(new ConstraintI(Location().introduce(), constants().lit_false));
            } else if (id->decl()->ti()->domain() == NULL) {
              id->decl()->ti()->domain(constants().lit_true);
              GCLock lock;
              std::vector<Expression*> args(2);
              args[0] = id;
              args[1] = constants().lit_true;
              Call* c = new Call(Location().introduce(), constants().ids.bool_eq, args);
              c->decl(env.model->matchFn(env, c, false));
              c->type(c->decl()->rtype(env, args, false));
              if (c->decl()->e()) {
                flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
              }
            }
            id = id->decl()->e() ? id->decl()->e()->dyn_cast<Id>() : NULL;
          }
        } else {
          GCLock lock;
          // extract domain information from added constraint if possible
          if (!e->isa<Call>() || checkDomainConstraints(env, e->cast<Call>())) {
            env.flat_addItem(new ConstraintI(Location().introduce(), e));
          }
        }
      }
      return constants().lit_true;
    } else if (vd == constants().var_false) {
      if (!isfalse(env, e)) {
        throw InternalError("not supported yet");
      }
      return constants().lit_true;
    } else if (vd == NULL) {
      if (e == NULL) return NULL;
      switch (e->eid()) {
        case Expression::E_INTLIT:
        case Expression::E_FLOATLIT:
        case Expression::E_BOOLLIT:
        case Expression::E_STRINGLIT:
        case Expression::E_ANON:
        case Expression::E_ID:
        case Expression::E_TIID:
        case Expression::E_SETLIT:
        case Expression::E_VARDECL:
          return e;
        case Expression::E_BINOP:
        case Expression::E_UNOP:
          return e;  /// TODO: should not happen once operators are evaluated
        case Expression::E_ARRAYACCESS:
        case Expression::E_COMP:
        case Expression::E_ITE:
        case Expression::E_LET:
        case Expression::E_TI:
          throw InternalError("unevaluated expression");
        case Expression::E_ARRAYLIT: {
          GCLock lock;
          ArrayLit* al = e->cast<ArrayLit>();
          /// TODO: review if limit of 10 is a sensible choice
          if (al->type().bt() == Type::BT_ANN || al->size() <= 10) return e;

          EnvI::CSEMap::iterator it = env.cse_map_find(al);
          if (it != env.cse_map_end()) {
            return it->second.r()->cast<VarDecl>()->id();
          }

          std::vector<TypeInst*> ranges(al->dims());
          for (unsigned int i = 0; i < ranges.size(); i++) {
            ranges[i] = new TypeInst(
                e->loc(), Type(),
                new SetLit(Location().introduce(), IntSetVal::a(al->min(i), al->max(i))));
          }
          ASTExprVec<TypeInst> ranges_v(ranges);
          assert(!al->type().isbot());
          Expression* domain = NULL;
          if (al->size() > 0 && (*al)[0]->type().isint()) {
            IntVal min = IntVal::infinity();
            IntVal max = -IntVal::infinity();
            for (unsigned int i = 0; i < al->size(); i++) {
              IntBounds ib = compute_int_bounds(env, (*al)[i]);
              if (!ib.valid) {
                min = -IntVal::infinity();
                max = IntVal::infinity();
                break;
              }
              min = std::min(min, ib.l);
              max = std::max(max, ib.u);
            }
            if (min != -IntVal::infinity() && max != IntVal::infinity()) {
              domain = new SetLit(Location().introduce(), IntSetVal::a(min, max));
            }
          }
          TypeInst* ti = new TypeInst(e->loc(), al->type(), ranges_v, domain);
          if (domain) ti->setComputedDomain(true);

          VarDecl* vd = newVarDecl(env, ctx, ti, NULL, NULL, al);
          EE ee(vd, NULL);
          env.cse_map_insert(al, ee);
          env.cse_map_insert(vd->e(), ee);
          return vd->id();
        }
        case Expression::E_CALL: {
          if (e->type().isann()) return e;
          GCLock lock;
          /// TODO: handle array types
          TypeInst* ti = new TypeInst(Location().introduce(), e->type());
          VarDecl* vd = newVarDecl(env, ctx, ti, NULL, NULL, e);
          if (vd->e()->type().bt() == Type::BT_INT && vd->e()->type().dim() == 0) {
            IntSetVal* ibv = NULL;
            if (vd->e()->type().is_set()) {
              ibv = compute_intset_bounds(env, vd->e());
            } else {
              IntBounds ib = compute_int_bounds(env, vd->e());
              if (ib.valid) {
                ibv = IntSetVal::a(ib.l, ib.u);
              }
            }
            if (ibv) {
              Id* id = vd->id();
              while (id != NULL) {
                if (id->decl()->ti()->domain()) {
                  IntSetVal* domain = eval_intset(env, id->decl()->ti()->domain());
                  IntSetRanges dr(domain);
                  IntSetRanges ibr(ibv);
                  Ranges::Inter<IntVal, IntSetRanges, IntSetRanges> i(dr, ibr);
                  IntSetVal* newibv = IntSetVal::ai(i);
                  if (ibv->card() == newibv->card()) {
                    id->decl()->ti()->setComputedDomain(true);
                  } else {
                    ibv = newibv;
                  }
                } else {
                  id->decl()->ti()->setComputedDomain(true);
                }
                if (id->type().st() == Type::ST_PLAIN && ibv->size() == 0) {
                  env.fail();
                } else {
                  id->decl()->ti()->domain(new SetLit(Location().introduce(), ibv));
                }
                id = id->decl()->e() ? id->decl()->e()->dyn_cast<Id>() : NULL;
              }
            }
          } else if (vd->e()->type().isbool()) {
            addCtxAnn(vd, ctx.b);
          } else if (vd->e()->type().bt() == Type::BT_FLOAT && vd->e()->type().dim() == 0) {
            FloatBounds fb = compute_float_bounds(env, vd->e());
            FloatSetVal* ibv = LinearTraits<FloatLit>::intersect_domain(NULL, fb.l, fb.u);
            if (fb.valid) {
              Id* id = vd->id();
              while (id != NULL) {
                if (id->decl()->ti()->domain()) {
                  FloatSetVal* domain = eval_floatset(env, id->decl()->ti()->domain());
                  FloatSetVal* ndomain =
                      LinearTraits<FloatLit>::intersect_domain(domain, fb.l, fb.u);
                  if (ibv && ndomain == domain) {
                    id->decl()->ti()->setComputedDomain(true);
                  } else {
                    ibv = ndomain;
                  }
                } else {
                  id->decl()->ti()->setComputedDomain(true);
                }
                if (LinearTraits<FloatLit>::domain_empty(ibv)) {
                  env.fail();
                } else {
                  id->decl()->ti()->domain(new SetLit(Location(), ibv));
                }
                id = id->decl()->e() ? id->decl()->e()->dyn_cast<Id>() : NULL;
              }
            }
          }

          return vd->id();
        }
        default:
          assert(false);
          return NULL;
      }
    } else {
      if (vd->e() == NULL) {
        Expression* ret = e;
        if (e == NULL || (e->type().ispar() && e->type().isbool())) {
          GCLock lock;
          bool isTrue = (e == NULL || eval_bool(env, e));

          // Check if redefinition of bool_eq exists, if yes call it
          std::vector<Expression*> args(2);
          args[0] = vd->id();
          args[1] = constants().boollit(isTrue);
          Call* c = new Call(Location().introduce(), constants().ids.bool_eq, args);
          c->decl(env.model->matchFn(env, c, false));
          c->type(c->decl()->rtype(env, args, false));
          bool didRewrite = false;
          if (c->decl()->e()) {
            flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
            didRewrite = true;
          }

          vd->e(constants().boollit(isTrue));
          if (vd->ti()->domain()) {
            if (vd->ti()->domain() != vd->e()) {
              env.fail();
              return vd->id();
            }
          } else {
            vd->ti()->domain(vd->e());
            vd->ti()->setComputedDomain(true);
          }
          if (didRewrite) {
            return vd->id();
          }
        } else {
          if (e->type().dim() > 0) {
            // Check that index sets match
            env.errorStack.clear();
            checkIndexSets(env, vd, e);
            if (vd->ti()->domain() && e->isa<ArrayLit>()) {
              ArrayLit* al = e->cast<ArrayLit>();
              if (e->type().bt() == Type::BT_INT) {
                IntSetVal* isv = eval_intset(env, vd->ti()->domain());
                for (unsigned int i = 0; i < al->size(); i++) {
                  if (Id* id = (*al)[i]->dyn_cast<Id>()) {
                    VarDecl* vdi = id->decl();
                    if (vdi->ti()->domain() == NULL) {
                      vdi->ti()->domain(vd->ti()->domain());
                    } else {
                      IntSetVal* vdi_dom = eval_intset(env, vdi->ti()->domain());
                      IntSetRanges isvr(isv);
                      IntSetRanges vdi_domr(vdi_dom);
                      Ranges::Inter<IntVal, IntSetRanges, IntSetRanges> inter(isvr, vdi_domr);
                      IntSetVal* newdom = IntSetVal::ai(inter);
                      if (newdom->size() == 0) {
                        env.fail();
                      } else {
                        IntSetRanges vdi_domr2(vdi_dom);
                        IntSetRanges newdomr(newdom);
                        if (!Ranges::equal(vdi_domr2, newdomr)) {
                          vdi->ti()->domain(new SetLit(Location().introduce(), newdom));
                          vdi->ti()->setComputedDomain(false);
                        }
                      }
                    }
                  } else {
                    // at this point, can only be a constant
                    assert((*al)[i]->type().ispar());
                    if (e->type().st() == Type::ST_PLAIN) {
                      IntVal iv = eval_int(env, (*al)[i]);
                      if (!isv->contains(iv)) {
                        std::ostringstream oss;
                        oss << "value " << iv << " outside declared array domain " << *isv;
                        env.fail(oss.str());
                      }
                    } else {
                      IntSetVal* aisv = eval_intset(env, (*al)[i]);
                      IntSetRanges aisv_r(aisv);
                      IntSetRanges isv_r(isv);
                      if (!Ranges::subset(aisv_r, isv_r)) {
                        std::ostringstream oss;
                        oss << "value " << *aisv << " outside declared array domain " << *isv;
                        env.fail(oss.str());
                      }
                    }
                  }
                }
                vd->ti()->setComputedDomain(true);
              } else if (e->type().bt() == Type::BT_FLOAT) {
                FloatSetVal* fsv = eval_floatset(env, vd->ti()->domain());
                for (unsigned int i = 0; i < al->size(); i++) {
                  if (Id* id = (*al)[i]->dyn_cast<Id>()) {
                    VarDecl* vdi = id->decl();
                    if (vdi->ti()->domain() == NULL) {
                      vdi->ti()->domain(vd->ti()->domain());
                    } else {
                      FloatSetVal* vdi_dom = eval_floatset(env, vdi->ti()->domain());
                      FloatSetRanges fsvr(fsv);
                      FloatSetRanges vdi_domr(vdi_dom);
                      Ranges::Inter<FloatVal, FloatSetRanges, FloatSetRanges> inter(fsvr, vdi_domr);
                      FloatSetVal* newdom = FloatSetVal::ai(inter);
                      if (newdom->size() == 0) {
                        env.fail();
                      } else {
                        FloatSetRanges vdi_domr2(vdi_dom);
                        FloatSetRanges newdomr(newdom);
                        if (!Ranges::equal(vdi_domr2, newdomr)) {
                          vdi->ti()->domain(new SetLit(Location().introduce(), newdom));
                          vdi->ti()->setComputedDomain(false);
                        }
                      }
                    }
                  } else {
                    // at this point, can only be a constant
                    assert((*al)[i]->type().ispar());
                    FloatVal fv = eval_float(env, (*al)[i]);
                    if (!fsv->contains(fv)) {
                      std::ostringstream oss;
                      oss << "value " << fv << " outside declared array domain " << *fsv;
                      env.fail(oss.str());
                    }
                  }
                }
                vd->ti()->setComputedDomain(true);
              }
            }
          } else if (Id* e_id = e->dyn_cast<Id>()) {
            if (e_id == vd->id()) {
              ret = vd->id();
            } else {
              ASTString cid;
              if (e->type().isint()) {
                if (e->type().isopt()) {
                  cid = ASTString("int_opt_eq");
                } else {
                  cid = constants().ids.int_.eq;
                }
              } else if (e->type().isbool()) {
                if (e->type().isopt()) {
                  cid = ASTString("bool_opt_eq");
                } else {
                  cid = constants().ids.bool_eq;
                }
              } else if (e->type().is_set()) {
                cid = constants().ids.set_eq;
              } else if (e->type().isfloat()) {
                cid = constants().ids.float_.eq;
              }
              if (cid != "") {
                GCLock lock;
                std::vector<Expression*> args(2);
                args[0] = vd->id();
                args[1] = e_id;
                Call* c = new Call(Location().introduce(), cid, args);
                c->decl(env.model->matchFn(env, c, false));
                c->type(c->decl()->rtype(env, args, false));
                if (c->type().isbool() && ctx.b != C_ROOT) {
                  addCtxAnn(vd, ctx.b);
                  addCtxAnn(e_id->decl(), ctx.b);
                }
                if (c->decl()->e()) {
                  flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
                  ret = vd->id();
                  vd->e(e);
                  env.vo_add_exp(vd);
                }
              }
            }
          }

          if (ret != vd->id()) {
            vd->e(ret);
            addPathAnnotation(env, ret);
            env.vo_add_exp(vd);
            ret = vd->id();
          }
          Id* vde_id = Expression::dyn_cast<Id>(vd->e());
          if (vde_id && vde_id->decl()->ti()->domain() == NULL) {
            if (vd->ti()->domain()) {
              GCLock lock;
              Expression* vd_dom = eval_par(env, vd->ti()->domain());
              vde_id->decl()->ti()->domain(vd_dom);
            }
          } else if (vd->e() && vd->e()->type().bt() == Type::BT_INT &&
                     vd->e()->type().dim() == 0) {
            GCLock lock;
            IntSetVal* ibv = NULL;
            if (vd->e()->type().is_set()) {
              ibv = compute_intset_bounds(env, vd->e());
            } else {
              IntBounds ib = compute_int_bounds(env, vd->e());
              if (ib.valid) {
                Call* call = vd->e()->dyn_cast<Call>();
                if (call && call->id() == constants().ids.lin_exp) {
                  ArrayLit* al = eval_array_lit(env, call->arg(1));
                  if (al->size() == 1) {
                    IntBounds check_zeroone = compute_int_bounds(env, (*al)[0]);
                    if (check_zeroone.l == 0 && check_zeroone.u == 1) {
                      ArrayLit* coeffs = eval_array_lit(env, call->arg(0));
                      std::vector<IntVal> newdom(2);
                      newdom[0] = 0;
                      newdom[1] = eval_int(env, (*coeffs)[0]) + eval_int(env, call->arg(2));
                      ibv = IntSetVal::a(newdom);
                    }
                  }
                }
                if (ibv == NULL) {
                  ibv = IntSetVal::a(ib.l, ib.u);
                }
              }
            }
            if (ibv) {
              if (vd->ti()->domain()) {
                IntSetVal* domain = eval_intset(env, vd->ti()->domain());
                IntSetRanges dr(domain);
                IntSetRanges ibr(ibv);
                Ranges::Inter<IntVal, IntSetRanges, IntSetRanges> i(dr, ibr);
                IntSetVal* newibv = IntSetVal::ai(i);
                if (ibv->card() == newibv->card()) {
                  vd->ti()->setComputedDomain(true);
                } else {
                  ibv = newibv;
                }
              } else {
                vd->ti()->setComputedDomain(true);
              }
              SetLit* ibv_l = new SetLit(Location().introduce(), ibv);
              vd->ti()->domain(ibv_l);
              if (Id* rhs_ident = vd->e()->dyn_cast<Id>()) {
                if (rhs_ident->decl()->ti()->domain()) {
                  IntSetVal* rhs_domain = eval_intset(env, rhs_ident->decl()->ti()->domain());
                  IntSetRanges dr(rhs_domain);
                  IntSetRanges ibr(ibv);
                  Ranges::Inter<IntVal, IntSetRanges, IntSetRanges> i(dr, ibr);
                  IntSetVal* rhs_newibv = IntSetVal::ai(i);
                  if (rhs_domain->card() != rhs_newibv->card()) {
                    rhs_ident->decl()->ti()->domain(ibv_l);
                    rhs_ident->decl()->ti()->setComputedDomain(false);
                    if (rhs_ident->decl()->type().isopt()) {
                      std::vector<Expression*> args(2);
                      args[0] = rhs_ident;
                      args[1] = ibv_l;
                      Call* c = new Call(Location().introduce(), "var_dom", args);
                      c->type(Type::varbool());
                      c->decl(env.model->matchFn(env, c, false));
                      (void)flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
                    }
                  }
                }
              }
              if (vd->type().isopt()) {
                std::vector<Expression*> args(2);
                args[0] = vd->id();
                args[1] = ibv_l;
                Call* c = new Call(Location().introduce(), "var_dom", args);
                c->type(Type::varbool());
                c->decl(env.model->matchFn(env, c, false));
                (void)flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
              }
            }
          } else if (vd->e() && vd->e()->type().bt() == Type::BT_FLOAT &&
                     vd->e()->type().dim() == 0) {
            GCLock lock;
            FloatSetVal* fbv = NULL;
            FloatBounds fb = compute_float_bounds(env, vd->e());
            if (fb.valid) {
              fbv = FloatSetVal::a(fb.l, fb.u);
            }
            if (fbv) {
              if (vd->ti()->domain()) {
                FloatSetVal* domain = eval_floatset(env, vd->ti()->domain());
                FloatSetRanges dr(domain);
                FloatSetRanges fbr(fbv);
                Ranges::Inter<FloatVal, FloatSetRanges, FloatSetRanges> i(dr, fbr);
                FloatSetVal* newfbv = FloatSetVal::ai(i);

                FloatSetRanges dr_eq(domain);
                FloatSetRanges newfbv_eq(newfbv);
                if (Ranges::equal(dr_eq, newfbv_eq)) {
                  vd->ti()->setComputedDomain(true);
                } else {
                  fbv = newfbv;
                }
              } else {
                vd->ti()->setComputedDomain(true);
              }
              SetLit* fbv_l = new SetLit(Location().introduce(), fbv);
              vd->ti()->domain(fbv_l);
              if (Id* rhs_ident = vd->e()->dyn_cast<Id>()) {
                if (rhs_ident->decl()->ti()->domain()) {
                  FloatSetVal* rhs_domain = eval_floatset(env, rhs_ident->decl()->ti()->domain());
                  FloatSetRanges dr(rhs_domain);
                  FloatSetRanges ibr(fbv);
                  Ranges::Inter<FloatVal, FloatSetRanges, FloatSetRanges> i(dr, ibr);
                  FloatSetVal* rhs_newfbv = FloatSetVal::ai(i);
                  if (rhs_domain->card() != rhs_newfbv->card()) {
                    rhs_ident->decl()->ti()->domain(fbv_l);
                    rhs_ident->decl()->ti()->setComputedDomain(false);
                    if (rhs_ident->decl()->type().isopt()) {
                      std::vector<Expression*> args(2);
                      args[0] = rhs_ident;
                      args[1] = fbv_l;
                      Call* c = new Call(Location().introduce(), "var_dom", args);
                      c->type(Type::varbool());
                      c->decl(env.model->matchFn(env, c, false));
                      (void)flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
                    }
                  }
                }
              }

              if (vd->type().isopt()) {
                std::vector<Expression*> args(2);
                args[0] = vd->id();
                args[1] = fbv_l;
                Call* c = new Call(Location().introduce(), "var_dom", args);
                c->type(Type::varbool());
                c->decl(env.model->matchFn(env, c, false));
                (void)flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
              }
            }
          }
        }
        return ret;
      } else if (vd == e) {
        return vd->id();
      } else if (vd->e() != e) {
        e = follow_id_to_decl(e);
        if (vd == e) return vd->id();
        switch (e->eid()) {
          case Expression::E_BOOLLIT: {
            Id* id = vd->id();
            while (id != NULL) {
              if (id->decl()->ti()->domain() &&
                  eval_bool(env, id->decl()->ti()->domain()) == e->cast<BoolLit>()->v()) {
                return constants().lit_true;
              } else if (id->decl()->ti()->domain() &&
                         eval_bool(env, id->decl()->ti()->domain()) != e->cast<BoolLit>()->v()) {
                GCLock lock;
                env.flat_addItem(new ConstraintI(Location().introduce(), constants().lit_false));
              } else {
                id->decl()->ti()->domain(e);
                GCLock lock;
                std::vector<Expression*> args(2);
                args[0] = id;
                args[1] = e;
                Call* c = new Call(Location().introduce(), constants().ids.bool_eq, args);
                c->decl(env.model->matchFn(env, c, false));
                c->type(c->decl()->rtype(env, args, false));
                if (c->decl()->e()) {
                  flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
                }
              }
              id = id->decl()->e() ? id->decl()->e()->dyn_cast<Id>() : NULL;
            }
            return constants().lit_true;
          }
          case Expression::E_VARDECL: {
            VarDecl* e_vd = e->cast<VarDecl>();
            if (vd->e() == e_vd->id() || e_vd->e() == vd->id()) return vd->id();
            if (e->type().dim() != 0) throw InternalError("not supported yet");
            GCLock lock;
            ASTString cid;
            if (e->type().isint()) {
              cid = constants().ids.int_.eq;
            } else if (e->type().isbool()) {
              cid = constants().ids.bool_eq;
            } else if (e->type().is_set()) {
              cid = constants().ids.set_eq;
            } else if (e->type().isfloat()) {
              cid = constants().ids.float_.eq;
            } else {
              throw InternalError("not yet implemented");
            }
            std::vector<Expression*> args(2);
            args[0] = vd->id();
            args[1] = e_vd->id();
            Call* c = new Call(vd->loc().introduce(), cid, args);
            c->decl(env.model->matchFn(env, c, false));
            c->type(c->decl()->rtype(env, args, false));
            flat_exp(env, Ctx(), c, constants().var_true, constants().var_true);
            return vd->id();
          }
          case Expression::E_CALL: {
            Call* c = e->cast<Call>();
            GCLock lock;
            Call* nc;
            std::vector<Expression*> args;
            if (c->id() == constants().ids.lin_exp) {
              ArrayLit* le_c = follow_id(c->arg(0))->cast<ArrayLit>();
              std::vector<Expression*> ncoeff(le_c->size());
              for (unsigned int i = static_cast<unsigned int>(ncoeff.size()); i--;)
                ncoeff[i] = (*le_c)[i];
              ncoeff.push_back(IntLit::a(-1));
              args.push_back(new ArrayLit(Location().introduce(), ncoeff));
              args[0]->type(le_c->type());
              ArrayLit* le_x = follow_id(c->arg(1))->cast<ArrayLit>();
              std::vector<Expression*> nx(le_x->size());
              for (unsigned int i = static_cast<unsigned int>(nx.size()); i--;) nx[i] = (*le_x)[i];
              nx.push_back(vd->id());
              args.push_back(new ArrayLit(Location().introduce(), nx));
              args[1]->type(le_x->type());
              args.push_back(c->arg(2));
              nc = new Call(c->loc().introduce(), constants().ids.lin_exp, args);
              nc->decl(env.model->matchFn(env, nc, false));
              if (nc->decl() == NULL) {
                throw InternalError("undeclared function or predicate " + nc->id().str());
              }
              nc->type(nc->decl()->rtype(env, args, false));
              BinOp* bop = new BinOp(nc->loc(), nc, BOT_EQ, IntLit::a(0));
              bop->type(Type::varbool());
              flat_exp(env, Ctx(), bop, constants().var_true, constants().var_true);
              return vd->id();
            } else {
              args.resize(c->n_args());
              for (unsigned int i = static_cast<unsigned int>(args.size()); i--;)
                args[i] = c->arg(i);
              args.push_back(vd->id());
              ASTString nid = c->id();

              if (c->id() == constants().ids.exists) {
                nid = constants().ids.array_bool_or;
              } else if (c->id() == constants().ids.forall) {
                nid = constants().ids.array_bool_and;
              } else if (vd->type().isbool()) {
                if (env.fopts.enable_imp && vd->ann().contains(constants().ctx.pos)) {
                  nid = env.halfReifyId(c->id());
                  if (env.model->matchFn(env, nid, args, false) == NULL) {
                    nid = env.reifyId(c->id());
                  }
                } else {
                  nid = env.reifyId(c->id());
                }
              }
              nc = new Call(c->loc().introduce(), nid, args);
            }
            nc->decl(env.model->matchFn(env, nc, false));
            if (nc->decl() == NULL) {
              throw InternalError("undeclared function or predicate " + nc->id().str());
            }
            nc->type(nc->decl()->rtype(env, args, false));
            makeDefinedVar(vd, nc);
            flat_exp(env, Ctx(), nc, constants().var_true, constants().var_true);
            return vd->id();
          } break;
          default:
            throw InternalError("not supported yet");
        }
      } else {
        return e;
      }
    }
  }
}

KeepAlive conj(EnvI& env, VarDecl* b, Ctx ctx, const std::vector<EE>& e) {
  if (!ctx.neg) {
    std::vector<Expression*> nontrue;
    for (unsigned int i = 0; i < e.size(); i++) {
      if (istrue(env, e[i].b())) continue;
      if (isfalse(env, e[i].b())) {
        return bind(env, Ctx(), b, constants().lit_false);
      }
      nontrue.push_back(e[i].b());
    }
    if (nontrue.empty()) {
      return bind(env, Ctx(), b, constants().lit_true);
    } else if (nontrue.size() == 1) {
      return bind(env, ctx, b, nontrue[0]);
    } else {
      if (b == constants().var_true) {
        for (unsigned int i = 0; i < nontrue.size(); i++) bind(env, ctx, b, nontrue[i]);
        return constants().lit_true;
      } else {
        GC::lock();
        std::vector<Expression*> args;
        ArrayLit* al = new ArrayLit(Location().introduce(), nontrue);
        al->type(Type::varbool(1));
        args.push_back(al);
        Call* ret = new Call(nontrue[0]->loc().introduce(), constants().ids.forall, args);
        ret->decl(env.model->matchFn(env, ret, false));
        ret->type(ret->decl()->rtype(env, args, false));
        KeepAlive ka(ret);
        GC::unlock();
        return flat_exp(env, ctx, ret, b, constants().var_true).r;
      }
    }
  } else {
    Ctx nctx = ctx;
    nctx.neg = false;
    // negated
    std::vector<Expression*> nonfalse;
    for (unsigned int i = 0; i < e.size(); i++) {
      if (istrue(env, e[i].b())) continue;
      if (isfalse(env, e[i].b())) {
        return bind(env, Ctx(), b, constants().lit_true);
      }
      nonfalse.push_back(e[i].b());
    }
    if (nonfalse.empty()) {
      return bind(env, Ctx(), b, constants().lit_false);
    } else if (nonfalse.size() == 1) {
      GC::lock();
      UnOp* uo = new UnOp(nonfalse[0]->loc(), UOT_NOT, nonfalse[0]);
      uo->type(Type::varbool());
      KeepAlive ka(uo);
      GC::unlock();
      return flat_exp(env, nctx, uo, b, constants().var_true).r;
    } else {
      if (b == constants().var_false) {
        for (unsigned int i = 0; i < nonfalse.size(); i++) bind(env, nctx, b, nonfalse[i]);
        return constants().lit_false;
      } else {
        GC::lock();
        std::vector<Expression*> args;
        for (unsigned int i = 0; i < nonfalse.size(); i++) {
          UnOp* uo = new UnOp(nonfalse[i]->loc(), UOT_NOT, nonfalse[i]);
          uo->type(Type::varbool());
          nonfalse[i] = uo;
        }
        ArrayLit* al = new ArrayLit(Location().introduce(), nonfalse);
        al->type(Type::varbool(1));
        args.push_back(al);
        Call* ret = new Call(Location().introduce(), constants().ids.exists, args);
        ret->decl(env.model->matchFn(env, ret, false));
        ret->type(ret->decl()->rtype(env, args, false));
        assert(ret->decl());
        KeepAlive ka(ret);
        GC::unlock();
        return flat_exp(env, nctx, ret, b, constants().var_true).r;
      }
    }
  }
}

TypeInst* eval_typeinst(EnvI& env, VarDecl* vd) {
  bool hasTiVars = vd->ti()->domain() && vd->ti()->domain()->isa<TIId>();
  for (unsigned int i = 0; i < vd->ti()->ranges().size(); i++) {
    hasTiVars = hasTiVars ||
                (vd->ti()->ranges()[i]->domain() && vd->ti()->ranges()[i]->domain()->isa<TIId>());
  }
  if (hasTiVars) {
    assert(vd->e());
    if (vd->e()->type().dim() == 0) return new TypeInst(Location().introduce(), vd->e()->type());
    ArrayLit* al = eval_array_lit(env, vd->e());
    std::vector<TypeInst*> dims(al->dims());
    for (unsigned int i = 0; i < dims.size(); i++) {
      dims[i] =
          new TypeInst(Location().introduce(), Type(),
                       new SetLit(Location().introduce(), IntSetVal::a(al->min(i), al->max(i))));
    }
    return new TypeInst(Location().introduce(), vd->e()->type(), dims,
                        eval_par(env, vd->ti()->domain()));
  } else {
    std::vector<TypeInst*> dims(vd->ti()->ranges().size());
    for (unsigned int i = 0; i < vd->ti()->ranges().size(); i++) {
      if (vd->ti()->ranges()[i]->domain()) {
        IntSetVal* isv = eval_intset(env, vd->ti()->ranges()[i]->domain());
        if (isv->size() > 1)
          throw EvalError(env, vd->ti()->ranges()[i]->domain()->loc(),
                          "array index set must be contiguous range");
        SetLit* sl = new SetLit(vd->ti()->ranges()[i]->loc(), isv);
        sl->type(Type::parsetint());
        dims[i] = new TypeInst(vd->ti()->ranges()[i]->loc(), Type(), sl);
      } else {
        dims[i] = new TypeInst(vd->ti()->ranges()[i]->loc(), Type(), NULL);
      }
    }
    Type t = (vd->e() && !vd->e()->type().isbot()) ? vd->e()->type() : vd->ti()->type();
    return new TypeInst(vd->ti()->loc(), t, dims, eval_par(env, vd->ti()->domain()));
  }
}

bool isBuiltin(FunctionI* decl) {
  return (decl->loc().filename() == "builtins.mzn" ||
          decl->loc().filename().endsWith("/builtins.mzn") ||
          decl->loc().filename() == "stdlib.mzn" ||
          decl->loc().filename().endsWith("/stdlib.mzn") ||
          decl->loc().filename() == "flatzinc_builtins.mzn" ||
          decl->loc().filename().endsWith("/flatzinc_builtins.mzn"));
}

KeepAlive flat_cv_exp(EnvI& env, Ctx ctx, Expression* e) {
  GCLock lock;
  if (e->type().ispar() && !e->type().cv()) {
    return eval_par(env, e);
  }
  if (e->type().isvar()) {
    EE ee = flat_exp(env, ctx, e, NULL, NULL);
    if (isfalse(env, ee.b()))
      throw FlatteningError(env, e->loc(), "cannot flatten partial function in this position");
    return ee.r();
  }
  switch (e->eid()) {
    case Expression::E_INTLIT:
    case Expression::E_FLOATLIT:
    case Expression::E_BOOLLIT:
    case Expression::E_STRINGLIT:
    case Expression::E_TIID:
    case Expression::E_VARDECL:
    case Expression::E_TI:
    case Expression::E_ANON:
      assert(false);
      return NULL;
    case Expression::E_ID: {
      Id* id = e->cast<Id>();
      return flat_cv_exp(env, ctx, id->decl()->e());
    }
    case Expression::E_SETLIT: {
      SetLit* sl = e->cast<SetLit>();
      if (sl->isv() || sl->fsv()) return sl;
      std::vector<Expression*> es(sl->v().size());
      GCLock lock;
      for (unsigned int i = 0; i < sl->v().size(); i++) {
        es[i] = flat_cv_exp(env, ctx, sl->v()[i])();
      }
      SetLit* sl_ret = new SetLit(Location().introduce(), es);
      Type t = sl->type();
      t.cv(false);
      sl_ret->type(t);
      return eval_par(env, sl_ret);
    }
    case Expression::E_ARRAYLIT: {
      ArrayLit* al = e->cast<ArrayLit>();
      std::vector<Expression*> es(al->size());
      GCLock lock;
      for (unsigned int i = 0; i < al->size(); i++) {
        es[i] = flat_cv_exp(env, ctx, (*al)[i])();
      }
      std::vector<std::pair<int, int> > dims(al->dims());
      for (int i = 0; i < al->dims(); i++) {
        dims[i] = std::make_pair(al->min(i), al->max(i));
      }
      Expression* al_ret = eval_par(env, new ArrayLit(Location().introduce(), es, dims));
      Type t = al->type();
      t.cv(false);
      al_ret->type(t);
      return al_ret;
    }
    case Expression::E_ARRAYACCESS: {
      ArrayAccess* aa = e->cast<ArrayAccess>();
      GCLock lock;
      Expression* av = flat_cv_exp(env, ctx, aa->v())();
      std::vector<Expression*> idx(aa->idx().size());
      for (unsigned int i = 0; i < aa->idx().size(); i++) {
        idx[i] = flat_cv_exp(env, ctx, aa->idx()[i])();
      }
      ArrayAccess* aa_ret = new ArrayAccess(Location().introduce(), av, idx);
      Type t = aa->type();
      t.cv(false);
      aa_ret->type(t);
      return eval_par(env, aa_ret);
    }
    case Expression::E_COMP: {
      Comprehension* c = e->cast<Comprehension>();
      GCLock lock;
      class EvalFlatCvExp {
      public:
        Ctx ctx;
        EvalFlatCvExp(Ctx& ctx0) : ctx(ctx0) {}
        typedef Expression* ArrayVal;
        Expression* e(EnvI& env, Expression* e) { return flat_cv_exp(env, ctx, e)(); }
        static Expression* exp(Expression* e) { return e; }
        Expression* flatten(EnvI& env, Expression* e0) {
          return flat_exp(env, Ctx(), e0, NULL, constants().var_true).r();
        }

      } eval(ctx);
      std::vector<Expression*> a = eval_comp<EvalFlatCvExp>(env, eval, c);

      Type t = Type::bot();
      bool allPar = true;
      for (unsigned int i = 0; i < a.size(); i++) {
        if (t == Type::bot()) t = a[i]->type();
        if (!a[i]->type().ispar()) allPar = false;
      }
      if (!allPar) t.ti(Type::TI_VAR);
      if (c->set())
        t.st(Type::ST_SET);
      else
        t.dim(c->type().dim());
      t.cv(false);
      if (c->set()) {
        if (c->type().ispar() && allPar) {
          SetLit* sl = new SetLit(c->loc().introduce(), a);
          sl->type(t);
          Expression* slr = eval_par(env, sl);
          slr->type(t);
          return slr;
        } else {
          throw InternalError("var set comprehensions not supported yet");
        }
      } else {
        ArrayLit* alr = new ArrayLit(Location().introduce(), a);
        alr->type(t);
        alr->flat(true);
        return alr;
      }
    }
    case Expression::E_ITE: {
      ITE* ite = e->cast<ITE>();
      for (int i = 0; i < ite->size(); i++) {
        KeepAlive ka = flat_cv_exp(env, ctx, ite->e_if(i));
        if (eval_bool(env, ka())) return flat_cv_exp(env, ctx, ite->e_then(i));
      }
      return flat_cv_exp(env, ctx, ite->e_else());
    }
    case Expression::E_BINOP: {
      BinOp* bo = e->cast<BinOp>();
      if (bo->op() == BOT_AND) {
        GCLock lock;
        Expression* lhs = flat_cv_exp(env, ctx, bo->lhs())();
        if (!eval_bool(env, lhs)) {
          return constants().lit_false;
        }
        return eval_par(env, flat_cv_exp(env, ctx, bo->rhs())());
      } else if (bo->op() == BOT_OR) {
        GCLock lock;
        Expression* lhs = flat_cv_exp(env, ctx, bo->lhs())();
        if (eval_bool(env, lhs)) {
          return constants().lit_true;
        }
        return eval_par(env, flat_cv_exp(env, ctx, bo->rhs())());
      }
      GCLock lock;
      BinOp* nbo = new BinOp(bo->loc().introduce(), flat_cv_exp(env, ctx, bo->lhs())(), bo->op(),
                             flat_cv_exp(env, ctx, bo->rhs())());
      nbo->type(bo->type());
      nbo->decl(bo->decl());
      return eval_par(env, nbo);
    }
    case Expression::E_UNOP: {
      UnOp* uo = e->cast<UnOp>();
      GCLock lock;
      UnOp* nuo = new UnOp(uo->loc(), uo->op(), flat_cv_exp(env, ctx, uo->e())());
      nuo->type(uo->type());
      return eval_par(env, nuo);
    }
    case Expression::E_CALL: {
      Call* c = e->cast<Call>();
      if (c->id() == "mzn_in_root_context") {
        return constants().boollit(ctx.b == C_ROOT);
      }
      if (ctx.b == C_ROOT && c->decl()->e() && c->decl()->e()->isa<BoolLit>()) {
        bool allBool = true;
        for (unsigned int i = 0; i < c->n_args(); i++) {
          if (c->arg(i)->type().bt() != Type::BT_BOOL) {
            allBool = false;
            break;
          }
        }
        if (allBool) {
          return c->decl()->e();
        }
      }
      std::vector<Expression*> args(c->n_args());
      GCLock lock;
      for (unsigned int i = 0; i < c->n_args(); i++) {
        args[i] = flat_cv_exp(env, ctx, c->arg(i))();
      }
      Call* nc = new Call(c->loc(), c->id(), args);
      nc->decl(c->decl());
      nc->type(c->type());
      return eval_par(env, nc);
    }
    case Expression::E_LET: {
      Let* l = e->cast<Let>();
      l->pushbindings();
      KeepAlive ret = flat_cv_exp(env, ctx, l->in());
      l->popbindings();
      return ret;
    }
  }
  throw InternalError("internal error");
}

void flatten(Env& e, FlatteningOptions opt) {
  try {
    EnvI& env = e.envi();
    env.fopts = opt;

    bool onlyRangeDomains = false;
    if (opt.onlyRangeDomains) {
      onlyRangeDomains = true;  // compulsory
    } else {
      GCLock lock;
      Call* check_only_range =
          new Call(Location(), "mzn_check_only_range_domains", std::vector<Expression*>());
      check_only_range->type(Type::parbool());
      check_only_range->decl(env.model->matchFn(e.envi(), check_only_range, false));
      onlyRangeDomains = eval_bool(e.envi(), check_only_range);
    }

    bool hadSolveItem = false;
    // Flatten main model
    class FV : public ItemVisitor {
    public:
      EnvI& env;
      bool& hadSolveItem;
      FV(EnvI& env0, bool& hadSolveItem0) : env(env0), hadSolveItem(hadSolveItem0) {}
      bool enter(Item* i) { return !(i->isa<ConstraintI>() && env.failed()); }
      void vVarDeclI(VarDeclI* v) {
        v->e()->ann().remove(constants().ann.output_var);
        v->e()->ann().removeCall(constants().ann.output_array);
        if (v->e()->ann().contains(constants().ann.output_only)) return;
        if (v->e()->type().ispar() && !v->e()->type().isopt() && !v->e()->type().cv() &&
            v->e()->type().dim() > 0 && v->e()->ti()->domain() == NULL &&
            (v->e()->type().bt() == Type::BT_INT || v->e()->type().bt() == Type::BT_FLOAT)) {
          // Compute bounds for array literals
          CallStackItem csi(env, v->e());
          GCLock lock;
          ArrayLit* al = eval_array_lit(env, v->e()->e());
          v->e()->e(al);
          checkIndexSets(env, v->e(), v->e()->e());
          if (v->e()->type().bt() == Type::BT_INT && v->e()->type().st() == Type::ST_PLAIN) {
            IntVal lb = IntVal::infinity();
            IntVal ub = -IntVal::infinity();
            for (unsigned int i = 0; i < al->size(); i++) {
              IntVal vi = eval_int(env, (*al)[i]);
              lb = std::min(lb, vi);
              ub = std::max(ub, vi);
            }
            GCLock lock;
            // v->e()->ti()->domain(new SetLit(Location().introduce(), IntSetVal::a(lb, ub)));
            // v->e()->ti()->setComputedDomain(true);
            setComputedDomain(env, v->e(), new SetLit(Location().introduce(), IntSetVal::a(lb, ub)),
                              true);
          } else if (v->e()->type().bt() == Type::BT_FLOAT &&
                     v->e()->type().st() == Type::ST_PLAIN) {
            FloatVal lb = FloatVal::infinity();
            FloatVal ub = -FloatVal::infinity();
            for (unsigned int i = 0; i < al->size(); i++) {
              FloatVal vi = eval_float(env, (*al)[i]);
              lb = std::min(lb, vi);
              ub = std::max(ub, vi);
            }
            GCLock lock;
            // v->e()->ti()->domain(new SetLit(Location().introduce(), FloatSetVal::a(lb, ub)));
            // v->e()->ti()->setComputedDomain(true);
            setComputedDomain(env, v->e(),
                              new SetLit(Location().introduce(), FloatSetVal::a(lb, ub)), true);
          }
        } else if (v->e()->type().isvar() || v->e()->type().isann()) {
          (void)flatten_id(env, Ctx(), v->e()->id(), NULL, constants().var_true, true);
        } else {
          if (v->e()->e() == NULL) {
            if (!v->e()->type().isann())
              throw EvalError(env, v->e()->loc(), "Undefined parameter", v->e()->id()->v());
          } else {
            CallStackItem csi(env, v->e());
            GCLock lock;
            Location v_loc = v->e()->e()->loc();
            if (!v->e()->e()->type().cv()) {
              v->e()->e(eval_par(env, v->e()->e()));
            } else {
              EE ee = flat_exp(env, Ctx(), v->e()->e(), NULL, constants().var_true);
              v->e()->e(ee.r());
            }
            if (v->e()->type().dim() > 0) {
              checkIndexSets(env, v->e(), v->e()->e());
              if (v->e()->ti()->domain() != NULL) {
                ArrayLit* al = eval_array_lit(env, v->e()->e());
                for (unsigned int i = 0; i < al->size(); i++) {
                  if (!checkParDomain(env, (*al)[i], v->e()->ti()->domain())) {
                    throw EvalError(env, v_loc, "parameter value out of range");
                  }
                }
              }
            } else {
              if (v->e()->ti()->domain() != NULL) {
                if (!checkParDomain(env, v->e()->e(), v->e()->ti()->domain())) {
                  throw EvalError(env, v_loc, "parameter value out of range");
                }
              }
            }
          }
        }
      }
      void vConstraintI(ConstraintI* ci) {
        (void)flat_exp(env, Ctx(), ci->e(), constants().var_true, constants().var_true);
      }
      void vSolveI(SolveI* si) {
        if (hadSolveItem) throw FlatteningError(env, si->loc(), "Only one solve item allowed");
        hadSolveItem = true;
        GCLock lock;
        SolveI* nsi = NULL;
        switch (si->st()) {
          case SolveI::ST_SAT:
            nsi = SolveI::sat(Location());
            break;
          case SolveI::ST_MIN: {
            Ctx ctx;
            ctx.i = C_NEG;
            nsi = SolveI::min(Location().introduce(),
                              flat_exp(env, ctx, si->e(), NULL, constants().var_true).r());
          } break;
          case SolveI::ST_MAX: {
            Ctx ctx;
            ctx.i = C_POS;
            nsi = SolveI::max(Location().introduce(),
                              flat_exp(env, Ctx(), si->e(), NULL, constants().var_true).r());
          } break;
        }
        for (ExpressionSetIter it = si->ann().begin(); it != si->ann().end(); ++it) {
          nsi->ann().add(flat_exp(env, Ctx(), *it, NULL, constants().var_true).r());
        }
        env.flat_addItem(nsi);
      }
    } _fv(env, hadSolveItem);
    iterItems<FV>(_fv, e.model());

    if (!hadSolveItem) {
      GCLock lock;
      e.envi().flat_addItem(SolveI::sat(Location().introduce()));
    }

    std::vector<VarDecl*> deletedVarDecls;

    // Create output model
    if (opt.keepOutputInFzn) {
      copyOutput(env);
    } else {
      createOutput(env, deletedVarDecls, opt.outputMode, opt.outputObjective, opt.outputOutputItem);
    }

    // Flatten remaining redefinitions
    Model& m = *e.flat();
    int startItem = 0;
    int endItem = m.size() - 1;

    FunctionI* int_lin_eq;
    {
      std::vector<Type> int_lin_eq_t(3);
      int_lin_eq_t[0] = Type::parint(1);
      int_lin_eq_t[1] = Type::varint(1);
      int_lin_eq_t[2] = Type::parint(0);
      GCLock lock;
      FunctionI* fi = env.model->matchFn(env, constants().ids.int_.lin_eq, int_lin_eq_t, false);
      int_lin_eq = (fi && fi->e()) ? fi : NULL;
    }
    FunctionI* array_bool_and;
    FunctionI* array_bool_or;
    FunctionI* array_bool_clause;
    FunctionI* array_bool_clause_reif;
    FunctionI* bool_xor;
    {
      std::vector<Type> array_bool_andor_t(2);
      array_bool_andor_t[0] = Type::varbool(1);
      array_bool_andor_t[1] = Type::varbool(0);
      GCLock lock;
      FunctionI* fi =
          env.model->matchFn(env, ASTString("array_bool_and"), array_bool_andor_t, false);
      array_bool_and = (fi && fi->e()) ? fi : NULL;
      fi = env.model->matchFn(env, ASTString("array_bool_or"), array_bool_andor_t, false);
      array_bool_or = (fi && fi->e()) ? fi : NULL;

      array_bool_andor_t[1] = Type::varbool(1);
      fi = env.model->matchFn(env, ASTString("bool_clause"), array_bool_andor_t, false);
      array_bool_clause = (fi && fi->e()) ? fi : NULL;

      array_bool_andor_t.push_back(Type::varbool());
      fi = env.model->matchFn(env, ASTString("bool_clause_reif"), array_bool_andor_t, false);
      array_bool_clause_reif = (fi && fi->e()) ? fi : NULL;

      std::vector<Type> bool_xor_t(3);
      bool_xor_t[0] = Type::varbool();
      bool_xor_t[1] = Type::varbool();
      bool_xor_t[2] = Type::varbool();
      fi = env.model->matchFn(env, constants().ids.bool_xor, bool_xor_t, false);
      bool_xor = (fi && fi->e()) ? fi : NULL;
    }

    std::vector<VarDeclI*> removedItems;
    env.collectVarDecls(true);

    while (startItem <= endItem || !env.modifiedVarDecls.empty()) {
      if (env.failed()) return;
      std::vector<int> agenda;
      for (int i = startItem; i <= endItem; i++) {
        agenda.push_back(i);
      }
      for (unsigned int i = 0; i < env.modifiedVarDecls.size(); i++) {
        agenda.push_back(env.modifiedVarDecls[i]);
      }
      env.modifiedVarDecls.clear();

      for (int ai = 0; ai < agenda.size(); ai++) {
        int i = agenda[ai];
        VarDeclI* vdi = m[i]->dyn_cast<VarDeclI>();
        bool keptVariable = true;
        /// Look at constraints
        if (vdi != NULL && !isOutput(vdi->e())) {
          if (0 < env.vo.occurrences(vdi->e())) {
            const auto it = env.vo._m.find(vdi->e()->id());
            if (env.vo._m.end() != it) {
              bool hasRedundantOccurrenciesOnly = true;
              for (const auto& c : it->second) {
                if (auto constrI = c->dyn_cast<ConstraintI>())
                  if (auto call = constrI->e()->dyn_cast<Call>())
                    if (call->id() == "mzn_reverse_map_var") continue;  // all good
                hasRedundantOccurrenciesOnly = false;
                break;
              }
              if (hasRedundantOccurrenciesOnly) {
                removedItems.push_back(vdi);
                env.flat_removeItem(vdi);
                env.vo.removeAllOccurrences(vdi->e());
                keptVariable = false;
                for (const auto& c : it->second) {
                  env.flat_removeItem(c);
                }
              }
            }
          } else {  // 0 occurrencies
            if (vdi->e()->e() && vdi->e()->ti()->domain()) {
              if (vdi->e()->type().isvar() && vdi->e()->type().isbool() &&
                  !vdi->e()->type().isopt() &&
                  Expression::equal(vdi->e()->ti()->domain(), constants().lit_true)) {
                GCLock lock;
                ConstraintI* ci = new ConstraintI(vdi->loc(), vdi->e()->e());
                if (vdi->e()->introduced()) {
                  removedItems.push_back(vdi);
                  env.flat_removeItem(vdi);
                  keptVariable = false;
                } else {
                  vdi->e()->e(NULL);
                }
                env.flat_addItem(ci);
              } else if (vdi->e()->type().ispar() || vdi->e()->ti()->computedDomain()) {
                removedItems.push_back(vdi);
                keptVariable = false;
              }
            } else {
              removedItems.push_back(vdi);
              env.flat_removeItem(vdi);
              keptVariable = false;
            }
          }
        }
        if (vdi && keptVariable && vdi->e()->type().dim() > 0 && vdi->e()->type().isvar()) {
          vdi->e()->ti()->domain(NULL);
        }
        if (vdi && keptVariable && vdi->e()->type().isint() && vdi->e()->type().isvar() &&
            vdi->e()->ti()->domain() != NULL) {
          GCLock lock;
          IntSetVal* dom = eval_intset(env, vdi->e()->ti()->domain());

          bool needRangeDomain = onlyRangeDomains;
          if (!needRangeDomain && dom->size() > 0) {
            if (dom->min(0).isMinusInfinity() || dom->max(dom->size() - 1).isPlusInfinity())
              needRangeDomain = true;
          }
          if (needRangeDomain) {
            if (dom->min(0).isMinusInfinity() || dom->max(dom->size() - 1).isPlusInfinity()) {
              TypeInst* nti = copy(env, vdi->e()->ti())->cast<TypeInst>();
              nti->domain(NULL);
              vdi->e()->ti(nti);
              if (dom->min(0).isFinite()) {
                std::vector<Expression*> args(2);
                args[0] = IntLit::a(dom->min(0));
                args[1] = vdi->e()->id();
                Call* call = new Call(Location().introduce(), constants().ids.int_.le, args);
                call->type(Type::varbool());
                call->decl(env.model->matchFn(env, call, false));
                env.flat_addItem(new ConstraintI(Location().introduce(), call));
              } else if (dom->max(dom->size() - 1).isFinite()) {
                std::vector<Expression*> args(2);
                args[0] = vdi->e()->id();
                args[1] = IntLit::a(dom->max(dom->size() - 1));
                Call* call = new Call(Location().introduce(), constants().ids.int_.le, args);
                call->type(Type::varbool());
                call->decl(env.model->matchFn(env, call, false));
                env.flat_addItem(new ConstraintI(Location().introduce(), call));
              }
            } else if (dom->size() > 1) {
              SetLit* newDom = new SetLit(Location().introduce(),
                                          IntSetVal::a(dom->min(0), dom->max(dom->size() - 1)));
              TypeInst* nti = copy(env, vdi->e()->ti())->cast<TypeInst>();
              nti->domain(newDom);
              vdi->e()->ti(nti);  /// TODO: WHY WAS THIS COMMENTED OUT IN DEBUG???
            }
            if (dom->size() > 1) {
              IntVal firstHole = dom->max(0) + 1;
              IntSetRanges domr(dom);
              ++domr;
              for (; domr(); ++domr) {
                for (IntVal i = firstHole; i < domr.min(); i++) {
                  std::vector<Expression*> args(2);
                  args[0] = vdi->e()->id();
                  args[1] = IntLit::a(i);
                  Call* call = new Call(vdi->e()->loc(), constants().ids.int_.ne, args);
                  call->type(Type::varbool());
                  call->decl(env.model->matchFn(env, call, false));
                  // Give distinct call stacks for each int_ne added
                  CallStackItem csi(env, IntLit::a(i));
                  env.flat_addItem(new ConstraintI(Location().introduce(), call));
                  firstHole = domr.max().plus(1);
                }
              }
            }
          }
        }
        if (vdi && keptVariable && vdi->e()->type().isfloat() && vdi->e()->type().isvar() &&
            vdi->e()->ti()->domain() != NULL) {
          GCLock lock;
          FloatSetVal* vdi_dom = eval_floatset(env, vdi->e()->ti()->domain());
          FloatVal vmin = vdi_dom->min();
          FloatVal vmax = vdi_dom->max();
          if (vmin == -FloatVal::infinity() && vmax == FloatVal::infinity()) {
            vdi->e()->ti()->domain(NULL);
          } else if (vmin == -FloatVal::infinity()) {
            vdi->e()->ti()->domain(NULL);
            std::vector<Expression*> args(2);
            args[0] = vdi->e()->id();
            args[1] = FloatLit::a(vmax);
            Call* call = new Call(Location().introduce(), constants().ids.float_.le, args);
            call->type(Type::varbool());
            call->decl(env.model->matchFn(env, call, false));
            env.flat_addItem(new ConstraintI(Location().introduce(), call));
          } else if (vmax == FloatVal::infinity()) {
            vdi->e()->ti()->domain(NULL);
            std::vector<Expression*> args(2);
            args[0] = FloatLit::a(vmin);
            args[1] = vdi->e()->id();
            Call* call = new Call(Location().introduce(), constants().ids.float_.le, args);
            call->type(Type::varbool());
            call->decl(env.model->matchFn(env, call, false));
            env.flat_addItem(new ConstraintI(Location().introduce(), call));
          } else if (vdi_dom->size() > 1) {
            BinOp* dom_ranges = new BinOp(vdi->e()->ti()->domain()->loc().introduce(),
                                          FloatLit::a(vmin), BOT_DOTDOT, FloatLit::a(vmax));
            vdi->e()->ti()->domain(dom_ranges);

            std::vector<Expression*> ranges;
            for (FloatSetRanges vdi_r(vdi_dom); vdi_r(); ++vdi_r) {
              ranges.push_back(FloatLit::a(vdi_r.min()));
              ranges.push_back(FloatLit::a(vdi_r.max()));
            }
            ArrayLit* al = new ArrayLit(Location().introduce(), ranges);
            al->type(Type::parfloat(1));
            std::vector<Expression*> args(2);
            args[0] = vdi->e()->id();
            args[1] = al;
            Call* call = new Call(Location().introduce(), constants().ids.float_.dom, args);
            call->type(Type::varbool());
            call->decl(env.model->matchFn(env, call, false));
            env.flat_addItem(new ConstraintI(Location().introduce(), call));
          }
        }
      }

      // rewrite some constraints if there are redefinitions
      for (int ai = 0; ai < agenda.size(); ai++) {
        int i = agenda[ai];
        if (VarDeclI* vdi = m[i]->dyn_cast<VarDeclI>()) {
          VarDecl* vd = vdi->e();
          if (!vdi->removed() && vd->e()) {
            bool isTrueVar =
                vd->type().isbool() && Expression::equal(vd->ti()->domain(), constants().lit_true);
            if (Call* c = vd->e()->dyn_cast<Call>()) {
              GCLock lock;
              Call* nc = NULL;
              if (c->id() == constants().ids.lin_exp) {
                if (int_lin_eq) {
                  std::vector<Expression*> args(c->n_args());
                  ArrayLit* le_c = follow_id(c->arg(0))->cast<ArrayLit>();
                  std::vector<Expression*> nc_c(le_c->size());
                  for (unsigned int i = static_cast<unsigned int>(nc_c.size()); i--;)
                    nc_c[i] = (*le_c)[i];
                  nc_c.push_back(IntLit::a(-1));
                  args[0] = new ArrayLit(Location().introduce(), nc_c);
                  args[0]->type(Type::parint(1));
                  ArrayLit* le_x = follow_id(c->arg(1))->cast<ArrayLit>();
                  std::vector<Expression*> nx(le_x->size());
                  for (unsigned int i = static_cast<unsigned int>(nx.size()); i--;)
                    nx[i] = (*le_x)[i];
                  nx.push_back(vd->id());
                  args[1] = new ArrayLit(Location().introduce(), nx);
                  args[1]->type(Type::varint(1));
                  IntVal d = c->arg(2)->cast<IntLit>()->v();
                  args[2] = IntLit::a(-d);
                  args[2]->type(Type::parint(0));
                  nc = new Call(c->loc().introduce(), ASTString("int_lin_eq"), args);
                  nc->type(Type::varbool());
                  nc->decl(int_lin_eq);
                }
              } else if (c->id() == constants().ids.exists) {
                if (array_bool_or) {
                  std::vector<Expression*> args(2);
                  args[0] = c->arg(0);
                  args[1] = vd->id();
                  nc = new Call(c->loc().introduce(), array_bool_or->id(), args);
                  nc->type(Type::varbool());
                  nc->decl(array_bool_or);
                }
              } else if (!isTrueVar && c->id() == constants().ids.forall) {
                if (array_bool_and) {
                  std::vector<Expression*> args(2);
                  args[0] = c->arg(0);
                  args[1] = vd->id();
                  nc = new Call(c->loc().introduce(), array_bool_and->id(), args);
                  nc->type(Type::varbool());
                  nc->decl(array_bool_and);
                }
              } else if (isTrueVar && c->id() == constants().ids.clause && array_bool_clause) {
                std::vector<Expression*> args(2);
                args[0] = c->arg(0);
                args[1] = c->arg(1);
                nc = new Call(c->loc().introduce(), array_bool_clause->id(), args);
                nc->type(Type::varbool());
                nc->decl(array_bool_clause);
              } else if (c->id() == constants().ids.clause && array_bool_clause_reif) {
                std::vector<Expression*> args(3);
                args[0] = c->arg(0);
                args[1] = c->arg(1);
                args[2] = vd->id();
                nc = new Call(c->loc().introduce(), array_bool_clause_reif->id(), args);
                nc->type(Type::varbool());
                nc->decl(array_bool_clause_reif);
              } else {
                if (isTrueVar) {
                  FunctionI* decl = env.model->matchFn(env, c, false);
                  env.cse_map_remove(c);
                  if (decl->e() || c->id() == constants().ids.forall) {
                    if (decl->e()) addPathAnnotation(env, decl->e());
                    c->decl(decl);
                    nc = c;
                  }
                } else {
                  std::vector<Expression*> args(c->n_args());
                  for (unsigned int i = static_cast<unsigned int>(args.size()); i--;)
                    args[i] = c->arg(i);
                  args.push_back(vd->id());
                  ASTString cid = c->id();
                  if (cid == constants().ids.clause && array_bool_clause_reif) {
                    nc = new Call(c->loc().introduce(), array_bool_clause_reif->id(), args);
                    nc->type(Type::varbool());
                    nc->decl(array_bool_clause_reif);
                  } else {
                    if (c->type().isbool() && vd->type().isbool()) {
                      if (env.fopts.enable_imp && vd->ann().contains(constants().ctx.pos)) {
                        cid = env.halfReifyId(c->id());
                        if (env.model->matchFn(env, cid, args, false) == NULL) {
                          cid = env.reifyId(c->id());
                        }
                      } else {
                        cid = env.reifyId(c->id());
                      }
                    }
                    FunctionI* decl = env.model->matchFn(env, cid, args, false);
                    if (decl && decl->e()) {
                      addPathAnnotation(env, decl->e());
                      nc = new Call(c->loc().introduce(), cid, args);
                      nc->type(Type::varbool());
                      nc->decl(decl);
                    }
                  }
                }
              }
              if (nc != NULL) {
                CollectDecls cd(env.vo, deletedVarDecls, vdi);
                topDown(cd, c);
                vd->e(NULL);
                // Need to remove right hand side from CSE map, otherwise
                // flattening of nc could assume c has already been flattened
                // to vd
                env.cse_map_remove(c);
                /// TODO: check if removing variables here makes sense:
                //                  if (!isOutput(vd) && env.vo.occurrences(vd)==0) {
                //                    removedItems.push_back(vdi);
                //                  }
                if (nc != c) {
                  makeDefinedVar(vd, nc);
                }
                StringLit* vsl = getLongestMznPathAnnotation(env, vdi->e());
                StringLit* csl = getLongestMznPathAnnotation(env, c);
                CallStackItem* vsi = NULL;
                CallStackItem* csi = NULL;
                if (vsl) vsi = new CallStackItem(env, vsl);
                if (csl) csi = new CallStackItem(env, csl);
                (void)flat_exp(env, Ctx(), nc, constants().var_true, constants().var_true);
                if (csi) delete csi;
                if (vsi) delete vsi;
              }
            }
          }
        } else if (ConstraintI* ci = m[i]->dyn_cast<ConstraintI>()) {
          if (!ci->removed()) {
            if (Call* c = ci->e()->dyn_cast<Call>()) {
              GCLock lock;
              Call* nc = NULL;
              if (c->id() == constants().ids.exists) {
                if (array_bool_or) {
                  std::vector<Expression*> args(2);
                  args[0] = c->arg(0);
                  args[1] = constants().lit_true;
                  nc = new Call(c->loc().introduce(), array_bool_or->id(), args);
                  nc->type(Type::varbool());
                  nc->decl(array_bool_or);
                }
              } else if (c->id() == constants().ids.forall) {
                if (array_bool_and) {
                  std::vector<Expression*> args(2);
                  args[0] = c->arg(0);
                  args[1] = constants().lit_true;
                  nc = new Call(c->loc().introduce(), array_bool_and->id(), args);
                  nc->type(Type::varbool());
                  nc->decl(array_bool_and);
                }
              } else if (c->id() == constants().ids.clause) {
                if (array_bool_clause) {
                  std::vector<Expression*> args(2);
                  args[0] = c->arg(0);
                  args[1] = c->arg(1);
                  nc = new Call(c->loc().introduce(), array_bool_clause->id(), args);
                  nc->type(Type::varbool());
                  nc->decl(array_bool_clause);
                }
              } else if (c->id() == constants().ids.bool_xor) {
                if (bool_xor) {
                  std::vector<Expression*> args(3);
                  args[0] = c->arg(0);
                  args[1] = c->arg(1);
                  args[2] = c->n_args() == 2 ? constants().lit_true : c->arg(2);
                  nc = new Call(c->loc().introduce(), bool_xor->id(), args);
                  nc->type(Type::varbool());
                  nc->decl(bool_xor);
                }
              } else {
                FunctionI* decl = env.model->matchFn(env, c, false);
                if (decl && decl->e()) {
                  nc = c;
                  nc->decl(decl);
                }
              }
              if (nc != NULL) {
                CollectDecls cd(env.vo, deletedVarDecls, ci);
                topDown(cd, c);
                ci->e(constants().lit_true);
                env.flat_removeItem(i);
                StringLit* sl = getLongestMznPathAnnotation(env, c);
                CallStackItem* csi = NULL;
                if (sl) csi = new CallStackItem(env, sl);
                (void)flat_exp(env, Ctx(), nc, constants().var_true, constants().var_true);
                if (csi) delete csi;
              }
            }
          }
        }
      }

      startItem = endItem + 1;
      endItem = m.size() - 1;
    }

    for (unsigned int i = 0; i < removedItems.size(); i++) {
      if (env.vo.occurrences(removedItems[i]->e()) == 0) {
        CollectDecls cd(env.vo, deletedVarDecls, removedItems[i]);
        topDown(cd, removedItems[i]->e()->e());
        env.flat_removeItem(removedItems[i]);
      }
    }

    // Add redefinitions for output variables that may have been redefined since createOutput
    for (unsigned int i = 0; i < env.output->size(); i++) {
      if (VarDeclI* vdi = (*env.output)[i]->dyn_cast<VarDeclI>()) {
        IdMap<KeepAlive>::iterator it;
        if (vdi->e()->e() == NULL &&
            (it = env.reverseMappers.find(vdi->e()->id())) != env.reverseMappers.end()) {
          GCLock lock;
          Call* rhs = copy(env, env.cmap, it->second())->cast<Call>();
          std::vector<Type> tv(rhs->n_args());
          for (unsigned int i = rhs->n_args(); i--;) {
            tv[i] = rhs->arg(i)->type();
            tv[i].ti(Type::TI_PAR);
          }
          FunctionI* decl = env.output->matchFn(env, rhs->id(), tv, false);
          Type t;
          if (decl == NULL) {
            FunctionI* origdecl = env.model->matchFn(env, rhs->id(), tv, false);
            if (origdecl == NULL) {
              throw FlatteningError(
                  env, rhs->loc(),
                  "function " + rhs->id().str() + " is used in output, par version needed");
            }
            if (!isBuiltin(origdecl)) {
              decl = copy(env, env.cmap, origdecl)->cast<FunctionI>();
              CollectOccurrencesE ce(env.output_vo, decl);
              topDown(ce, decl->e());
              topDown(ce, decl->ti());
              for (unsigned int i = decl->params().size(); i--;) topDown(ce, decl->params()[i]);
              env.output->registerFn(env, decl);
              env.output->addItem(decl);
            } else {
              decl = origdecl;
            }
          }
          rhs->decl(decl);
          outputVarDecls(env, vdi, rhs);

          removeIsOutput(vdi->e()->flat());
          vdi->e()->e(rhs);
        }
      }
    }

    for (unsigned int i = 0; i < m.size(); i++) {
      if (ConstraintI* ci = m[i]->dyn_cast<ConstraintI>()) {
        if (Call* c = ci->e()->dyn_cast<Call>()) {
          if (c->decl() == constants().var_redef) {
            CollectDecls cd(env.vo, deletedVarDecls, ci);
            topDown(cd, c);
            env.flat_removeItem(i);
          }
        }
      }
    }

    while (!deletedVarDecls.empty()) {
      VarDecl* cur = deletedVarDecls.back();
      deletedVarDecls.pop_back();
      if (env.vo.occurrences(cur) == 0 && !isOutput(cur)) {
        if (CollectDecls::varIsFree(cur)) {
          IdMap<int>::iterator cur_idx = env.vo.idx.find(cur->id());
          if (cur_idx != env.vo.idx.end() && !m[cur_idx->second]->removed()) {
            CollectDecls cd(env.vo, deletedVarDecls, m[cur_idx->second]->cast<VarDeclI>());
            topDown(cd, cur->e());
            env.flat_removeItem(cur_idx->second);
          }
        }
      }
    }

    if (!opt.keepOutputInFzn) {
      finaliseOutput(env, deletedVarDecls);
    }

    while (!deletedVarDecls.empty()) {
      VarDecl* cur = deletedVarDecls.back();
      deletedVarDecls.pop_back();
      if (env.vo.occurrences(cur) == 0 && !isOutput(cur)) {
        if (CollectDecls::varIsFree(cur)) {
          IdMap<int>::iterator cur_idx = env.vo.idx.find(cur->id());
          if (cur_idx != env.vo.idx.end() && !m[cur_idx->second]->removed()) {
            CollectDecls cd(env.vo, deletedVarDecls, m[cur_idx->second]->cast<VarDeclI>());
            topDown(cd, cur->e());
            env.flat_removeItem(cur_idx->second);
          }
        }
      }
    }

    cleanupOutput(env);
  } catch (ModelInconsistent&) {
  }
}

void clearInternalAnnotations(Expression* e) {
  e->ann().remove(constants().ann.promise_total);
  e->ann().remove(constants().ann.maybe_partial);
  e->ann().remove(constants().ann.add_to_output);
  e->ann().remove(constants().ann.rhs_from_assignment);
  // Remove defines_var(x) annotation where x is par
  std::vector<Expression*> removeAnns;
  for (ExpressionSetIter anns = e->ann().begin(); anns != e->ann().end(); ++anns) {
    if (Call* c = (*anns)->dyn_cast<Call>()) {
      if (c->id() == constants().ann.defines_var && c->arg(0)->type().ispar()) {
        removeAnns.push_back(c);
      }
    }
  }
  for (unsigned int i = 0; i < removeAnns.size(); i++) {
    e->ann().remove(removeAnns[i]);
  }
}

std::vector<Expression*> cleanup_vardecl(EnvI& env, VarDeclI* vdi, VarDecl* vd) {
  std::vector<Expression*> added_constraints;

  // In FlatZinc par variables have RHSs, not domains
  if (vd->type().ispar()) {
    vd->ann().clear();
    vd->introduced(false);
    vd->ti()->domain(NULL);
  }

  // In FlatZinc the RHS of a VarDecl must be a literal, Id or empty
  // Example:
  //   var 1..5: x = function(y)
  // becomes:
  //   var 1..5: x;
  //   relation(x, y);
  if (vd->type().isvar() && vd->type().isbool()) {
    bool is_fixed = (vd->ti()->domain() != NULL);
    if (Expression::equal(vd->ti()->domain(), constants().lit_true)) {
      // Ex: var true: b = e()

      // Store RHS
      Expression* ve = vd->e();
      vd->e(constants().lit_true);
      vd->ti()->domain(NULL);
      // Ex: var bool: b = true

      // If vd had a RHS
      if (ve != NULL) {
        if (Call* vcc = ve->dyn_cast<Call>()) {
          // Convert functions to relations:
          //   exists([x]) => array_bool_or([x],true)
          //   forall([x]) => array_bool_and([x],true)
          //   clause([x]) => bool_clause([x])
          ASTString cid;
          std::vector<Expression*> args;
          if (vcc->id() == constants().ids.exists) {
            cid = constants().ids.array_bool_or;
            args.push_back(vcc->arg(0));
            args.push_back(constants().lit_true);
          } else if (vcc->id() == constants().ids.forall) {
            cid = constants().ids.array_bool_and;
            args.push_back(vcc->arg(0));
            args.push_back(constants().lit_true);
          } else if (vcc->id() == constants().ids.clause) {
            cid = constants().ids.bool_clause;
            args.push_back(vcc->arg(0));
            args.push_back(vcc->arg(1));
          }

          if (args.size() == 0) {
            // Post original RHS as stand alone constraint
            ve = vcc;
          } else {
            // Create new call, retain annotations from original RHS
            Call* nc = new Call(vcc->loc().introduce(), cid, args);
            nc->type(vcc->type());
            nc->ann().merge(vcc->ann());
            ve = nc;
          }
        } else if (Id* id = ve->dyn_cast<Id>()) {
          if (id->decl()->ti()->domain() != constants().lit_true) {
            // Inconsistent assignment: post bool_eq(y, true)
            std::vector<Expression*> args(2);
            args[0] = id;
            args[1] = constants().lit_true;
            GCLock lock;
            ve = new Call(Location().introduce(), constants().ids.bool_eq, args);
          } else {
            // Don't post this
            ve = constants().lit_true;
          }
        }
        // Post new constraint
        if (ve != constants().lit_true) {
          clearInternalAnnotations(ve);
          added_constraints.push_back(ve);
        }
      }
    } else {
      // Ex: var false: b = e()
      if (vd->e() != NULL) {
        if (vd->e()->eid() == Expression::E_CALL) {
          // Convert functions to relations:
          //  var false: b = exists([x]) => array_bool_or([x], b)
          //  var false: b = forall([x]) => array_bool_and([x], b)
          //  var false: b = clause([x]) => bool_clause_reif([x], b)
          const Call* c = vd->e()->cast<Call>();
          GCLock lock;
          vd->e(NULL);
          ASTString cid;
          std::vector<Expression*> args(c->n_args());
          for (unsigned int i = args.size(); i--;) args[i] = c->arg(i);
          if (is_fixed) {
            args.push_back(constants().lit_false);
          } else {
            args.push_back(vd->id());
          }
          if (c->id() == constants().ids.exists) {
            cid = constants().ids.array_bool_or;
          } else if (c->id() == constants().ids.forall) {
            cid = constants().ids.array_bool_and;
          } else if (c->id() == constants().ids.clause) {
            cid = constants().ids.bool_clause_reif;
          } else {
            if (env.fopts.enable_imp && vd->ann().contains(constants().ctx.pos)) {
              cid = env.halfReifyId(c->id());
              if (env.model->matchFn(env, cid, args, false) == NULL) {
                cid = env.reifyId(c->id());
              }
            } else {
              cid = env.reifyId(c->id());
            }
          }
          Call* nc = new Call(c->loc().introduce(), cid, args);
          nc->type(c->type());
          FunctionI* decl = env.model->matchFn(env, nc, false);
          if (decl == NULL) {
            throw FlatteningError(
                env, c->loc(),
                "'" + c->id().str() +
                    "' is used in a reified context but no reified version is available");
          }
          nc->decl(decl);
          if (!is_fixed) {
            makeDefinedVar(vd, nc);
          }
          nc->ann().merge(c->ann());
          clearInternalAnnotations(nc);
          added_constraints.push_back(nc);
        } else {
          assert(vd->e()->eid() == Expression::E_ID || vd->e()->eid() == Expression::E_BOOLLIT);
        }
      }
      if (Expression::equal(vd->ti()->domain(), constants().lit_false)) {
        vd->ti()->domain(NULL);
        vd->e(constants().lit_false);
      }
    }
    if (vdi != NULL && is_fixed && env.vo.occurrences(vd) == 0) {
      if (isOutput(vd)) {
        VarDecl* vd_output = (*env.output)[env.output_vo_flat.find(vd)]->cast<VarDeclI>()->e();
        if (vd_output->e() == NULL) {
          vd_output->e(vd->e());
        }
      }
      env.flat_removeItem(vdi);
    }
  } else if (vd->type().isvar() && vd->type().dim() == 0) {
    // Int or Float var
    if (vd->e() != NULL) {
      if (const Call* cc = vd->e()->dyn_cast<Call>()) {
        // Remove RHS from vd
        vd->e(NULL);

        std::vector<Expression*> args(cc->n_args());
        ASTString cid;
        if (cc->id() == constants().ids.lin_exp) {
          // a = lin_exp([1],[b],5) => int_lin_eq([1,-1],[b,a],-5):: defines_var(a)
          ArrayLit* le_c = follow_id(cc->arg(0))->cast<ArrayLit>();
          std::vector<Expression*> nc(le_c->size());
          for (unsigned int i = static_cast<unsigned int>(nc.size()); i--;) nc[i] = (*le_c)[i];
          if (le_c->type().bt() == Type::BT_INT) {
            cid = constants().ids.int_.lin_eq;
            nc.push_back(IntLit::a(-1));
            args[0] = new ArrayLit(Location().introduce(), nc);
            args[0]->type(Type::parint(1));
            ArrayLit* le_x = follow_id(cc->arg(1))->cast<ArrayLit>();
            std::vector<Expression*> nx(le_x->size());
            for (unsigned int i = static_cast<unsigned int>(nx.size()); i--;) nx[i] = (*le_x)[i];
            nx.push_back(vd->id());
            args[1] = new ArrayLit(Location().introduce(), nx);
            args[1]->type(le_x->type());
            IntVal d = cc->arg(2)->cast<IntLit>()->v();
            args[2] = IntLit::a(-d);
          } else {
            // float
            cid = constants().ids.float_.lin_eq;
            nc.push_back(FloatLit::a(-1.0));
            args[0] = new ArrayLit(Location().introduce(), nc);
            args[0]->type(Type::parfloat(1));
            ArrayLit* le_x = follow_id(cc->arg(1))->cast<ArrayLit>();
            std::vector<Expression*> nx(le_x->size());
            for (unsigned int i = static_cast<unsigned int>(nx.size()); i--;) nx[i] = (*le_x)[i];
            nx.push_back(vd->id());
            args[1] = new ArrayLit(Location().introduce(), nx);
            args[1]->type(le_x->type());
            FloatVal d = cc->arg(2)->cast<FloatLit>()->v();
            args[2] = FloatLit::a(-d);
          }
        } else {
          if (cc->id() == "card") {
            // card is 'set_card' in old FlatZinc
            cid = constants().ids.set_card;
          } else {
            cid = cc->id();
          }
          for (unsigned int i = static_cast<unsigned int>(args.size()); i--;) args[i] = cc->arg(i);
          args.push_back(vd->id());
        }
        Call* nc = new Call(cc->loc().introduce(), cid, args);
        nc->type(cc->type());
        makeDefinedVar(vd, nc);
        nc->ann().merge(cc->ann());

        clearInternalAnnotations(nc);
        added_constraints.push_back(nc);
      } else {
        // RHS must be literal or Id
        assert(vd->e()->eid() == Expression::E_ID || vd->e()->eid() == Expression::E_INTLIT ||
               vd->e()->eid() == Expression::E_FLOATLIT ||
               vd->e()->eid() == Expression::E_BOOLLIT || vd->e()->eid() == Expression::E_SETLIT);
      }
    }
  } else if (vd->type().dim() > 0) {
    // vd is an array

    // If RHS is an Id, follow id to RHS
    // a = [1,2,3]; b = a;
    // vd = b => vd = [1,2,3]
    if (!vd->e()->isa<ArrayLit>()) {
      vd->e(follow_id(vd->e()));
    }

    // If empty array or 1 indexed, continue
    if (vd->ti()->ranges().size() == 1 && vd->ti()->ranges()[0]->domain() != NULL &&
        vd->ti()->ranges()[0]->domain()->isa<SetLit>()) {
      IntSetVal* isv = vd->ti()->ranges()[0]->domain()->cast<SetLit>()->isv();
      if (isv && (isv->size() == 0 || isv->min(0) == 1)) return added_constraints;
    }

    // Array should be 1 indexed since ArrayLit is 1 indexed
    assert(vd->e() != NULL);
    ArrayLit* al = NULL;
    Expression* e = vd->e();
    while (al == NULL) {
      switch (e->eid()) {
        case Expression::E_ARRAYLIT:
          al = e->cast<ArrayLit>();
          break;
        case Expression::E_ID:
          e = e->cast<Id>()->decl()->e();
          break;
        default:
          assert(false);
      }
    }
    al->make1d();
    IntSetVal* isv = IntSetVal::a(1, al->length());
    if (vd->ti()->ranges().size() == 1) {
      vd->ti()->ranges()[0]->domain(new SetLit(Location().introduce(), isv));
    } else {
      std::vector<TypeInst*> r(1);
      r[0] = new TypeInst(vd->ti()->ranges()[0]->loc(), vd->ti()->ranges()[0]->type(),
                          new SetLit(Location().introduce(), isv));
      ASTExprVec<TypeInst> ranges(r);
      TypeInst* ti = new TypeInst(vd->ti()->loc(), vd->ti()->type(), ranges, vd->ti()->domain());
      vd->ti(ti);
    }
  }

  // Remove boolean context annotations used only on compilation
  vd->ann().remove(constants().ctx.mix);
  vd->ann().remove(constants().ctx.pos);
  vd->ann().remove(constants().ctx.neg);
  vd->ann().remove(constants().ctx.root);
  vd->ann().remove(constants().ann.promise_total);
  vd->ann().remove(constants().ann.add_to_output);
  vd->ann().remove(constants().ann.mzn_check_var);
  vd->ann().remove(constants().ann.rhs_from_assignment);
  vd->ann().removeCall(constants().ann.mzn_check_enum_var);

  return added_constraints;
}

Expression* cleanup_constraint(EnvI& env, std::unordered_set<Item*>& globals, Expression* ce) {
  clearInternalAnnotations(ce);

  if (Call* vc = ce->dyn_cast<Call>()) {
    for (unsigned int i = 0; i < vc->n_args(); i++) {
      // Change array indicies to be 1 indexed
      if (ArrayLit* al = vc->arg(i)->dyn_cast<ArrayLit>()) {
        if (al->dims() > 1 || al->min(0) != 1) {
          al->make1d();
        }
      }
    }
    // Convert functions to relations:
    //   exists([x]) => array_bool_or([x],true)
    //   forall([x]) => array_bool_and([x],true)
    //   clause([x]) => bool_clause([x])
    //   bool_xor([x],[y]) => bool_xor([x],[y],true)
    if (vc->id() == constants().ids.exists) {
      GCLock lock;
      vc->id(constants().ids.array_bool_or);
      std::vector<Expression*> args(2);
      args[0] = vc->arg(0);
      args[1] = constants().lit_true;
      ASTExprVec<Expression> argsv(args);
      vc->args(argsv);
      vc->decl(env.model->matchFn(env, vc, false));
    } else if (vc->id() == constants().ids.forall) {
      GCLock lock;
      vc->id(constants().ids.array_bool_and);
      std::vector<Expression*> args(2);
      args[0] = vc->arg(0);
      args[1] = constants().lit_true;
      ASTExprVec<Expression> argsv(args);
      vc->args(argsv);
      vc->decl(env.model->matchFn(env, vc, false));
    } else if (vc->id() == constants().ids.clause) {
      GCLock lock;
      vc->id(constants().ids.bool_clause);
      vc->decl(env.model->matchFn(env, vc, false));
    } else if (vc->id() == constants().ids.bool_xor && vc->n_args() == 2) {
      GCLock lock;
      std::vector<Expression*> args(3);
      args[0] = vc->arg(0);
      args[1] = vc->arg(1);
      args[2] = constants().lit_true;
      ASTExprVec<Expression> argsv(args);
      vc->args(argsv);
      vc->decl(env.model->matchFn(env, vc, false));
    }

    // If vc->decl() is a solver builtin and has not been added to the
    // FlatZinc, add it
    if (vc->decl() && vc->decl() != constants().var_redef && !vc->decl()->from_stdlib() &&
        globals.find(vc->decl()) == globals.end()) {
      env.flat_addItem(vc->decl());
      globals.insert(vc->decl());
    }
    return ce;
  } else if (Id* id = ce->dyn_cast<Id>()) {
    // Ex: constraint b; => constraint bool_eq(b, true);
    std::vector<Expression*> args(2);
    args[0] = id;
    args[1] = constants().lit_true;
    GCLock lock;
    return new Call(Location().introduce(), constants().ids.bool_eq, args);
  } else if (BoolLit* bl = ce->dyn_cast<BoolLit>()) {
    // Ex: true => delete; false => bool_eq(false, true);
    if (!bl->v()) {
      GCLock lock;
      std::vector<Expression*> args(2);
      args[0] = constants().lit_false;
      args[1] = constants().lit_true;
      Call* neq = new Call(Location().introduce(), constants().ids.bool_eq, args);
      return neq;
    } else {
      return NULL;
    }
  } else {
    return ce;
  }
}

void oldflatzinc(Env& e) {
  Model* m = e.flat();

  // Mark annotations and optional variables for removal
  for (unsigned int i = 0; i < m->size(); i++) {
    Item* item = (*m)[i];
    if (VarDeclI* vdi = item->dyn_cast<VarDeclI>()) {
      if (item->cast<VarDeclI>()->e()->type().ot() == Type::OT_OPTIONAL ||
          item->cast<VarDeclI>()->e()->type().bt() == Type::BT_ANN) {
        e.envi().flat_removeItem(i);
      }
    }
  }

  EnvI& env = e.envi();

  int msize = m->size();

  // Predicate declarations of solver builtins
  std::unordered_set<Item*> globals;

  // Record indices of VarDeclIs with Id RHS for sorting & unification
  std::vector<int> declsWithIds;
  for (int i = 0; i < msize; i++) {
    if ((*m)[i]->removed()) continue;
    if (VarDeclI* vdi = (*m)[i]->dyn_cast<VarDeclI>()) {
      GCLock lock;
      VarDecl* vd = vdi->e();
      std::vector<Expression*> added_constraints = cleanup_vardecl(e.envi(), vdi, vd);
      // Record whether this VarDecl is equal to an Id (aliasing)
      if (vd->e() && vd->e()->isa<Id>()) {
        declsWithIds.push_back(i);
        vdi->e()->payload(-static_cast<int>(i) - 1);
      } else {
        vdi->e()->payload(i);
      }
      for (auto nc : added_constraints) {
        Expression* new_ce = cleanup_constraint(e.envi(), globals, nc);
        if (new_ce) {
          e.envi().flat_addItem(new ConstraintI(Location().introduce(), new_ce));
        }
      }
    } else if (ConstraintI* ci = (*m)[i]->dyn_cast<ConstraintI>()) {
      Expression* new_ce = cleanup_constraint(e.envi(), globals, ci->e());
      if (new_ce) {
        ci->e(new_ce);
      } else {
        ci->remove();
      }
    } else if (FunctionI* fi = (*m)[i]->dyn_cast<FunctionI>()) {
      if (Let* let = Expression::dyn_cast<Let>(fi->e())) {
        GCLock lock;
        std::vector<Expression*> new_let;
        for (unsigned int i = 0; i < let->let().size(); i++) {
          Expression* let_e = let->let()[i];
          if (VarDecl* vd = let_e->dyn_cast<VarDecl>()) {
            std::vector<Expression*> added_constraints = cleanup_vardecl(e.envi(), NULL, vd);
            new_let.push_back(vd);
            for (auto nc : added_constraints) new_let.push_back(nc);
          } else {
            Expression* new_ce = cleanup_constraint(e.envi(), globals, let_e);
            if (new_ce) {
              new_let.push_back(new_ce);
            }
          }
        }
        fi->e(new Let(let->loc(), new_let, let->in()));
      }
    } else if (SolveI* si = (*m)[i]->dyn_cast<SolveI>()) {
      if (si->e() && si->e()->type().ispar()) {
        // Introduce VarDecl if objective expression is par
        GCLock lock;
        TypeInst* ti = new TypeInst(Location().introduce(), si->e()->type(), NULL);
        VarDecl* constantobj = new VarDecl(Location().introduce(), ti, e.envi().genId(), si->e());
        si->e(constantobj->id());
        e.envi().flat_addItem(new VarDeclI(Location().introduce(), constantobj));
      }
    }
  }

  // Sort VarDecls in FlatZinc so that VarDecls are declared before use
  std::vector<VarDeclI*> sortedVarDecls(declsWithIds.size());
  int vdCount = 0;
  for (unsigned int i = 0; i < declsWithIds.size(); i++) {
    VarDecl* cur = (*m)[declsWithIds[i]]->cast<VarDeclI>()->e();
    std::vector<int> stack;
    while (cur && cur->payload() < 0) {
      stack.push_back(cur->payload());
      if (Id* id = cur->e()->dyn_cast<Id>()) {
        cur = id->decl();
      } else {
        cur = NULL;
      }
    }
    for (unsigned int i = static_cast<unsigned int>(stack.size()); i--;) {
      VarDeclI* vdi = (*m)[-stack[i] - 1]->cast<VarDeclI>();
      vdi->e()->payload(-vdi->e()->payload() - 1);
      sortedVarDecls[vdCount++] = vdi;
    }
  }
  for (unsigned int i = 0; i < declsWithIds.size(); i++) {
    (*m)[declsWithIds[i]] = sortedVarDecls[i];
  }

  // Remove marked items
  m->compact();
  e.envi().output->compact();

  for (IdMap<VarOccurrences::Items>::iterator it = env.vo._m.begin(); it != env.vo._m.end(); ++it) {
    std::vector<Item*> toRemove;
    for (VarOccurrences::Items::iterator iit = it->second.begin(); iit != it->second.end(); ++iit) {
      if ((*iit)->removed()) {
        toRemove.push_back(*iit);
      }
    }
    for (unsigned int i = 0; i < toRemove.size(); i++) {
      it->second.erase(toRemove[i]);
    }
  }

  class Cmp {
  public:
    bool operator()(Item* i, Item* j) {
      if (i->iid() == Item::II_FUN || j->iid() == Item::II_FUN) {
        if (i->iid() == j->iid()) return false;
        return i->iid() == Item::II_FUN;
      }
      if (i->iid() == Item::II_SOL) {
        assert(j->iid() != i->iid());
        return false;
      }
      if (j->iid() == Item::II_SOL) {
        assert(j->iid() != i->iid());
        return true;
      }
      if (i->iid() == Item::II_VD) {
        if (j->iid() != i->iid()) return true;
        if (i->cast<VarDeclI>()->e()->type().ispar() && j->cast<VarDeclI>()->e()->type().isvar())
          return true;
        if (j->cast<VarDeclI>()->e()->type().ispar() && i->cast<VarDeclI>()->e()->type().isvar())
          return false;
        if (i->cast<VarDeclI>()->e()->type().dim() == 0 &&
            j->cast<VarDeclI>()->e()->type().dim() != 0)
          return true;
        if (i->cast<VarDeclI>()->e()->type().dim() != 0 &&
            j->cast<VarDeclI>()->e()->type().dim() == 0)
          return false;
        if (i->cast<VarDeclI>()->e()->e() == NULL && j->cast<VarDeclI>()->e()->e() != NULL)
          return true;
        if (i->cast<VarDeclI>()->e()->e() && j->cast<VarDeclI>()->e()->e() &&
            !i->cast<VarDeclI>()->e()->e()->isa<Id>() && j->cast<VarDeclI>()->e()->e()->isa<Id>())
          return true;
      }
      return false;
    }
  } _cmp;
  // Perform final sorting
  std::stable_sort(m->begin(), m->end(), _cmp);
}

FlatModelStatistics statistics(Model* m) {
  Model* flat = m;
  FlatModelStatistics stats;
  for (unsigned int i = 0; i < flat->size(); i++) {
    if (!(*flat)[i]->removed()) {
      if (VarDeclI* vdi = (*flat)[i]->dyn_cast<VarDeclI>()) {
        Type t = vdi->e()->type();
        if (t.isvar() && t.dim() == 0) {
          if (t.is_set())
            stats.n_set_vars++;
          else if (t.isint())
            stats.n_int_vars++;
          else if (t.isbool())
            stats.n_bool_vars++;
          else if (t.isfloat())
            stats.n_float_vars++;
        }
      } else if (ConstraintI* ci = (*flat)[i]->dyn_cast<ConstraintI>()) {
        if (Call* call = ci->e()->dyn_cast<Call>()) {
          if (call->id().endsWith("_reif")) {
            stats.n_reif_ct++;
          } else if (call->id().endsWith("_imp")) {
            stats.n_imp_ct++;
          }
          if (call->n_args() > 0) {
            Type all_t;
            for (unsigned int i = 0; i < call->n_args(); i++) {
              Type t = call->arg(i)->type();
              if (t.isvar()) {
                if (t.st() == Type::ST_SET)
                  all_t = t;
                else if (t.bt() == Type::BT_FLOAT && all_t.st() != Type::ST_SET)
                  all_t = t;
                else if (t.bt() == Type::BT_INT && all_t.bt() != Type::BT_FLOAT &&
                         all_t.st() != Type::ST_SET)
                  all_t = t;
                else if (t.bt() == Type::BT_BOOL && all_t.bt() != Type::BT_INT &&
                         all_t.bt() != Type::BT_FLOAT && all_t.st() != Type::ST_SET)
                  all_t = t;
              }
            }
            if (all_t.isvar()) {
              if (all_t.st() == Type::ST_SET)
                stats.n_set_ct++;
              else if (all_t.bt() == Type::BT_INT)
                stats.n_int_ct++;
              else if (all_t.bt() == Type::BT_BOOL)
                stats.n_bool_ct++;
              else if (all_t.bt() == Type::BT_FLOAT)
                stats.n_float_ct++;
            }
          }
        }
      }
    }
  }
  return stats;
}

}  // namespace MiniZinc