fix #4662

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/sat/smt/sat_th.h

@@ -0,0 +1,66 @@
+/*++
+Copyright (c) 2020 Microsoft Corporation
+
+Module Name:
+
+    sat_th.h
+
+Abstract:
+
+    Theory plugins
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2020-08-25
+
+--*/
+#pragma once
+
+#include "sat/smt/sat_smt.h"
+#include "ast/euf/euf_egraph.h"
+
+namespace sat {
+    
+
+    class th_dependencies {
+    public:
+        th_dependencies() {}
+        euf::enode * const* begin() const { return nullptr; }
+        euf::enode * const* end() const { return nullptr; }
+
+        /*
+         * \brief add dependency: dst depends on src.
+         */
+        void add(euf::enode* src, euf::enode* dst);
+
+        /*
+         * \brief sort dependencies.
+         */
+        void sort();
+    };
+
+    class th_internalizer {
+    public:
+        virtual literal internalize(sat_internalizer& si, expr* e, bool sign, bool root) = 0;
+        virtual ~th_internalizer() {}
+    };
+
+    class th_model_builder {
+    public:
+
+        virtual ~th_model_builder() {}
+
+        /**
+           \brief compute the value for enode \c n and store the value in \c values 
+           for the root of the class of \c n.
+         */
+        virtual void add_value(euf::enode* n, expr_ref_vector& values) = 0;
+
+        /**
+           \brief compute dependencies for node n
+         */
+        virtual void add_dep(euf::enode* n, th_dependencies& dep) = 0;
+    };
+
+
+}