adding ematching engine, fixing seq_unicode

src/ast/euf/CMakeLists.txt

@@ -3,6 +3,7 @@ z3_add_component(euf
     euf_enode.cpp
     euf_etable.cpp
     euf_egraph.cpp
+    euf_mam.cpp
   COMPONENT_DEPENDENCIES
     ast
     util

src/ast/euf/euf_egraph.h

@@ -247,6 +247,8 @@ namespace euf {
         */
         bool are_diseq(enode* a, enode* b) const;
 
+        enode * get_enode_eq_to(func_decl * f, unsigned num_args, enode * const * args) { UNREACHABLE(); return nullptr; }
+
         /**
            \brief Maintain and update cursor into propagated consequences.
            The result of get_literal() is a pair (n, is_eq)
@@ -279,6 +281,11 @@ namespace euf {
         template <typename T>
         void explain_eq(ptr_vector<T>& justifications, enode* a, enode* b);
         enode_vector const& nodes() const { return m_nodes; }
+
+        ast_manager& get_manager() { return m; }
+        bool is_relevant(enode* n) const { return true; } // TODO
+        bool resource_limits_exceeded() const { return false; } // TODO
+
         void invariant();
         void copy_from(egraph const& src, std::function<void*(void*)>& copy_justification);
         struct e_pp {

src/ast/euf/euf_enode.h

@@ -18,6 +18,7 @@ Author:
 #include "util/vector.h"
 #include "util/id_var_list.h"
 #include "util/lbool.h"
+#include "util/approx_set.h"
 #include "ast/ast.h"
 #include "ast/euf/euf_justification.h"
 
@@ -60,6 +61,9 @@ namespace euf {
         th_var_list   m_th_vars;
         justification m_justification;
         unsigned      m_num_args{ 0 };
+        signed char         m_lbl_hash { -1 };  // It is different from -1, if enode is used in a pattern
+        approx_set          m_lbls;
+        approx_set          m_plbls;
         enode* m_args[0];
 
         friend class enode_args;
@@ -138,6 +142,7 @@ namespace euf {
         lbool value() const { return m_value;  }
         unsigned bool_var() const { return m_bool_var; }
         bool is_cgr() const { return this == m_cg; }
+        enode* get_cg() const { return m_cg; }
         bool commutative() const { return m_commutative; }
         void mark_interpreted() { SASSERT(num_args() == 0); m_interpreted = true; }
         bool merge_enabled() const { return m_merge_enabled; }
@@ -183,6 +188,16 @@ namespace euf {
         unsigned get_expr_id() const { return m_expr->get_id(); }
         unsigned get_root_id() const { return m_root->m_expr->get_id(); }
         bool children_are_roots() const;
+        enode* get_next() const { return m_next; }
+
+        bool has_lbl_hash() const { UNREACHABLE(); return false; } // TODO
+        unsigned char get_lbl_hash() const { UNREACHABLE(); return 0; } // TOD0
+        void set_lbl_hash(egraph& e) { UNREACHABLE(); }
+        approx_set & get_lbls() { return m_lbls; }        
+        approx_set & get_plbls() { return m_plbls; }        
+        const approx_set & get_lbls() const { return m_lbls; }        
+        const approx_set & get_plbls() const { return m_plbls; }
+
 
         theory_var get_th_var(theory_id id) const { return m_th_vars.find(id); }
         theory_var get_closest_th_var(theory_id id) const;

src/ast/euf/euf_mam.h

@@ -0,0 +1,66 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    euf_mam.h
+
+Abstract:
+
+    Matching Abstract Machine
+
+Author:
+
+    Leonardo de Moura (leonardo) 2007-02-13.
+    Nikolaj Bjorner (nbjorner) 2021-01-22.
+
+--*/
+#pragma once
+
+#include "ast/ast.h"
+#include "ast/euf/euf_egraph.h"
+#include <functional>
+
+namespace euf {
+
+    /**
+       \brief Matching Abstract Machine (MAM)
+    */
+    class mam {
+        friend class mam_impl;
+
+        mam() {}
+
+    public:
+
+        static mam * mk(egraph & ctx, 
+                        std::function<void(quantifier*, app*, unsigned, enode* const*, unsigned)>& add_instance);
+        
+        virtual ~mam() {}
+        
+        virtual void add_pattern(quantifier * q, app * mp) = 0;
+
+        virtual void push_scope() = 0;
+
+        virtual void pop_scope(unsigned num_scopes) = 0;
+
+        virtual void match() = 0;
+        
+        virtual void rematch(bool use_irrelevant = false) = 0;
+
+        virtual bool has_work() const = 0;
+        
+        virtual void add_eq_eh(enode * r1, enode * r2) = 0;
+
+        virtual void reset() = 0;
+
+        virtual std::ostream& display(std::ostream& out) = 0;
+        
+        virtual void on_match(quantifier * q, app * pat, unsigned num_bindings, enode * const * bindings, unsigned max_generation) = 0;
+        
+        virtual bool is_shared(enode * n) const = 0;
+
+        virtual bool check_missing_instances() = 0;
+    };
+};
+