force-push on new_eq, new_diseq in user propagator, other fixes to Python bindings for user propagator

This update allows the python bindings for user-propagator to handle functions that are declared to be registered with the user propagator plugin. It fixes a bug in UserPropagateBase.add to allow registering terms dynamically during search.
It also fixes a bug in theory_user_propagate as scopes were not fully pushed when the solver gets the callbacks for new equalities and new disequalities.
It also adds equality and disequality interfaces to the sat/smt solver version (which isn't being exercised in earnest yet)

src/api/python/z3/z3.py

@@ -11364,12 +11364,12 @@ def to_ContextObj(ptr,):
     return ctx
 
 
-def user_prop_fresh(ctx, new_ctx):
+def user_prop_fresh(ctx, _new_ctx):
     _prop_closures.set_threaded()
     prop = _prop_closures.get(ctx)
     nctx = Context()
     Z3_del_context(nctx.ctx)
-    new_ctx = to_ContextObj(new_ctx)
+    new_ctx = to_ContextObj(_new_ctx)
     nctx.ctx = new_ctx
     nctx.eh = Z3_set_error_handler(new_ctx, z3_error_handler)
     nctx.owner = False
@@ -11390,6 +11390,13 @@ def user_prop_fixed(ctx, cb, id, value):
     prop.fixed(id, value)
     prop.cb = None
 
+def user_prop_created(ctx, cb, id):
+    prop = _prop_closures.get(ctx)
+    prop.cb = cb
+    id = _to_expr_ref(to_Ast(id), prop.ctx())
+    prop.created(id)
+    prop.cb = None
+    
 def user_prop_final(ctx, cb):
     prop = _prop_closures.get(ctx)
     prop.cb = cb
@@ -11417,10 +11424,32 @@ _user_prop_push = Z3_push_eh(user_prop_push)
 _user_prop_pop = Z3_pop_eh(user_prop_pop)
 _user_prop_fresh = Z3_fresh_eh(user_prop_fresh)
 _user_prop_fixed = Z3_fixed_eh(user_prop_fixed)
+_user_prop_created = Z3_created_eh(user_prop_created)
 _user_prop_final = Z3_final_eh(user_prop_final)
 _user_prop_eq = Z3_eq_eh(user_prop_eq)
 _user_prop_diseq = Z3_eq_eh(user_prop_diseq)
 
+def PropagateFunction(name, *sig):
+    """Create a function that gets tracked by user propagator.
+       Every term headed by this function symbol is tracked.
+       If a term is fixed and the fixed callback is registered a
+       callback is invoked that the term headed by this function is fixed.
+    """
+    sig = _get_args(sig)
+    if z3_debug():
+        _z3_assert(len(sig) > 0, "At least two arguments expected")
+    arity = len(sig) - 1
+    rng = sig[arity]
+    if z3_debug():
+        _z3_assert(is_sort(rng), "Z3 sort expected")
+    dom = (Sort * arity)()
+    for i in range(arity):
+        if z3_debug():
+            _z3_assert(is_sort(sig[i]), "Z3 sort expected")
+        dom[i] = sig[i].ast
+    ctx = rng.ctx
+    return FuncDeclRef(Z3_solver_propagate_declare(ctx.ref(), to_symbol(name, ctx), arity, dom, rng.ast), ctx)
+      
 
 class UserPropagateBase:
 
@@ -11443,6 +11472,7 @@ class UserPropagateBase:
         self.final = None
         self.eq = None
         self.diseq = None
+        self.created = None
         if ctx:
             self.fresh_ctx = ctx
         if s:
@@ -11473,6 +11503,13 @@ class UserPropagateBase:
             Z3_solver_propagate_fixed(self.ctx_ref(), self.solver.solver, _user_prop_fixed)
         self.fixed = fixed
 
+    def add_created(self, created):
+        assert not self.created
+        assert not self._ctx
+        if self.solver:
+            Z3_solver_propagate_created(self.ctx_ref(), self.solver.solver, _user_prop_created)
+        self.created = created
+        
     def add_final(self, final):
         assert not self.final
         assert not self._ctx
@@ -11504,9 +11541,12 @@ class UserPropagateBase:
         raise Z3Exception("fresh needs to be overwritten")
 
     def add(self, e):
-        assert self.solver
         assert not self._ctx
-        Z3_solver_propagate_register(self.ctx_ref(), self.solver.solver, e.ast)
+        if self.solver:
+            Z3_solver_propagate_register(self.ctx_ref(), self.solver.solver, e.ast)
+        else:
+            Z3_solver_propagate_register_cb(self.ctx_ref(), ctypes.c_void_p(self.cb), e.ast)
+        
 
     #
     # Propagation can only be invoked as during a fixed or final callback.
@@ -11519,5 +11559,5 @@ class UserPropagateBase:
         Z3_solver_propagate_consequence(e.ctx.ref(), ctypes.c_void_p(
             self.cb), num_fixed, _ids, num_eqs, _lhs, _rhs, e.ast)
 
-    def conflict(self, deps):
-        self.propagate(BoolVal(False, self.ctx()), deps, eqs=[])
+    def conflict(self, deps = [], eqs = []):
+        self.propagate(BoolVal(False, self.ctx()), deps, eqs)

src/ast/ast.cpp

@@ -1429,7 +1429,7 @@ ast_manager::~ast_manager() {
     }
     m_plugins.reset();
     while (!m_ast_table.empty()) {
-        DEBUG_CODE(IF_VERBOSE(0, verbose_stream() << "ast_manager LEAKED: " << m_ast_table.size() << std::endl););
+        DEBUG_CODE(IF_VERBOSE(1, verbose_stream() << "ast_manager LEAKED: " << m_ast_table.size() << std::endl););
         ptr_vector<ast> roots;
         ast_mark mark;
         for (ast * n : m_ast_table) {
@@ -1465,22 +1465,21 @@ ast_manager::~ast_manager() {
                 break;
             }
         }
-        for (ast * n : m_ast_table) {
-            if (!mark.is_marked(n)) {
+        for (ast * n : m_ast_table) 
+            if (!mark.is_marked(n)) 
                 roots.push_back(n);
-            }
-        }
+
         SASSERT(!roots.empty());
         for (unsigned i = 0; i < roots.size(); ++i) {
             ast* a = roots[i];
             DEBUG_CODE(
-                std::cout << "Leaked: ";
-                if (is_sort(a)) {
-                    std::cout << to_sort(a)->get_name() << "\n";
-                }
-                else {
-                    std::cout << mk_ll_pp(a, *this, false) << "id: " << a->get_id() << "\n";
-                });
+                IF_VERBOSE(1, 
+                           verbose_stream() << "Leaked: ";
+                           if (is_sort(a)) 
+                               verbose_stream() << to_sort(a)->get_name() << "\n";
+                           else 
+                               verbose_stream() << mk_ll_pp(a, *this, false) << "id: " << a->get_id() << "\n";
+                           ););
             a->m_ref_count = 0;
             delete_node(a);
         }

src/sat/smt/user_solver.cpp

@@ -131,6 +131,21 @@ namespace user_solver {
         m_id2justification.setx(v, lits, sat::literal_vector());
         m_fixed_eh(m_user_context, this, var2expr(v), lit.sign() ? m.mk_false() : m.mk_true());
     }
+    
+    void solver::new_eq_eh(euf::th_eq const& eq) {
+        if (!m_eq_eh)
+            return;
+        force_push();
+        m_eq_eh(m_user_context, this, var2expr(eq.v1()), var2expr(eq.v2()));
+    }
+    
+    void solver::new_diseq_eh(euf::th_eq const& de) {
+        if (!m_diseq_eh)
+            return;
+        force_push();
+        m_diseq_eh(m_user_context, this, var2expr(eq.v1()), var2expr(eq.v2()));
+    }
+
 
     void solver::push_core() {
         th_euf_solver::push_core();

src/sat/smt/user_solver.h

@@ -144,6 +144,10 @@ namespace user_solver {
         bool get_case_split(sat::bool_var& var, lbool &phase) override;
         
         void asserted(sat::literal lit) override;
+        bool use_diseqs() const override { return (bool)m_diseq_eh; }
+        void new_eq_eh(euf::th_eq const& eq) override;
+        void new_diseq_eh(euf::th_eq const& de) override;
+
         sat::check_result check() override;
         void push_core() override;
         void pop_core(unsigned n) override;

src/smt/smt_context.cpp

@@ -821,6 +821,8 @@ namespace smt {
                 SASSERT(t2 != null_theory_id);
                 theory_var v1 = m_fparams.m_new_core2th_eq ? get_closest_var(n1, t2) : r1->get_th_var(t2);
 
+                TRACE("merge_theory_vars", tout << get_theory(t2)->get_name() << ": " << v2 << " == " << v1 << "\n");
+
                 if (v1 != null_theory_var) {
                     // only send the equality to the theory, if the equality was not propagated by it.
                     if (t2 != from_th)
@@ -839,6 +841,7 @@ namespace smt {
                 SASSERT(v1 != null_theory_var);
                 SASSERT(t1 != null_theory_id);
                 theory_var v2 = r2->get_th_var(t1);
+                TRACE("merge_theory_vars", tout << get_theory(t1)->get_name() << ": " << v2 << " == " << v1 << "\n");
                 if (v2 == null_theory_var) {
                     r2->add_th_var(v1, t1, m_region);
                     push_new_th_diseqs(r2, v1, get_theory(t1));

src/smt/theory_user_propagator.cpp

@@ -146,7 +146,9 @@ final_check_status theory_user_propagator::final_check_eh() {
     catch (...) {
       throw default_exception("Exception thrown in \"final\"-callback");
     }
+    CTRACE("user_propagate", can_propagate(), tout << "can propagate\n");
     propagate();
+    CTRACE("user_propagate", ctx.inconsistent(), tout << "inconsistent\n");
     // check if it became inconsistent or something new was propagated/registered
     bool done = (sz1 == m_prop.size()) && (sz2 == m_expr2var.size()) && !ctx.inconsistent();
     return done ? FC_DONE : FC_CONTINUE;
@@ -298,13 +300,17 @@ void theory_user_propagator::propagate_consequence(prop_info const& prop) {
     m_eqs.reset();
     for (expr* id : prop.m_ids)
         m_lits.append(m_id2justification[expr2var(id)]);
-    for (auto const& p : prop.m_eqs)
-        m_eqs.push_back(enode_pair(get_enode(expr2var(p.first)), get_enode(expr2var(p.second))));
-    DEBUG_CODE(for (auto const& p : m_eqs) VERIFY(p.first->get_root() == p.second->get_root()););
+    for (auto const& [a,b] : prop.m_eqs)
+        if (a != b)
+            m_eqs.push_back(enode_pair(get_enode(expr2var(a)), get_enode(expr2var(b))));
+    DEBUG_CODE(for (auto const& [a, b] : m_eqs) VERIFY(a->get_root() == b->get_root()););
     DEBUG_CODE(for (expr* e : prop.m_ids) VERIFY(m_fixed.contains(expr2var(e))););
     DEBUG_CODE(for (literal lit : m_lits) VERIFY(ctx.get_assignment(lit) == l_true););
     
-    TRACE("user_propagate", tout << "propagating #" << prop.m_conseq->get_id() << ": " << prop.m_conseq << "\n");
+    TRACE("user_propagate", tout << "propagating #" << prop.m_conseq->get_id() << ": " << prop.m_conseq << "\n";
+          for (auto const& [a,b] : m_eqs) tout << enode_pp(a, ctx) << " == " << enode_pp(b, ctx) << "\n";
+          for (expr* e : prop.m_ids) tout << mk_pp(e, m) << "\n";
+          for (literal lit : m_lits) tout << lit << "\n");
     
     if (m.is_false(prop.m_conseq)) {
         js = ctx.mk_justification(
@@ -341,9 +347,9 @@ void theory_user_propagator::propagate_new_fixed(prop_info const& prop) {
 
 
 void theory_user_propagator::propagate() {
-    TRACE("user_propagate", tout << "propagating queue head: " << m_qhead << " prop queue: " << m_prop.size() << "\n");
     if (m_qhead == m_prop.size() && m_to_add_qhead == m_to_add.size())
         return;
+    TRACE("user_propagate", tout << "propagating queue head: " << m_qhead << " prop queue: " << m_prop.size() << "\n");
     force_push();
     
     unsigned qhead = m_to_add_qhead;

src/smt/theory_user_propagator.h

@@ -140,10 +140,11 @@ namespace smt {
         bool get_case_split(bool_var& var, bool& is_pos);
 
         theory * mk_fresh(context * new_ctx) override;
+        char const* get_name() const override { return "user_propagate"; }
         bool internalize_atom(app* atom, bool gate_ctx) override;
         bool internalize_term(app* term) override;
-        void new_eq_eh(theory_var v1, theory_var v2) override { if (m_eq_eh) m_eq_eh(m_user_context, this, var2expr(v1), var2expr(v2)); }
-        void new_diseq_eh(theory_var v1, theory_var v2) override { if (m_diseq_eh) m_diseq_eh(m_user_context, this, var2expr(v1), var2expr(v2)); }
+        void new_eq_eh(theory_var v1, theory_var v2) override { force_push(); if (m_eq_eh) m_eq_eh(m_user_context, this, var2expr(v1), var2expr(v2)); }
+        void new_diseq_eh(theory_var v1, theory_var v2) override { force_push(); if (m_diseq_eh) m_diseq_eh(m_user_context, this, var2expr(v1), var2expr(v2)); }
         bool use_diseqs() const override { return ((bool)m_diseq_eh); }
         bool build_models() const override { return false; }
         final_check_status final_check_eh() override;