adding plugin for local search strings

src/ast/sls/sls_seq_plugin.h

@@ -0,0 +1,81 @@
+/*++
+Copyright (c) 2024 Microsoft Corporation
+
+Module Name:
+
+    sls_seq_plugin.h
+
+Abstract:
+
+    Sequence/String SLS
+    
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2024-11-22
+    
+--*/
+#pragma once
+
+#include "ast/sls/sls_context.h"
+#include "ast/seq_decl_plugin.h"
+
+
+namespace sls {
+    
+    class seq_plugin : public plugin {
+        struct value {
+            value(ast_manager& m): evalue(m) {}
+            zstring  svalue;
+            expr_ref evalue;
+        };
+
+        struct eval {
+            eval(ast_manager& m):
+                val0(m), val1(m) {}
+            value val0;
+            value val1;
+        };
+
+        seq_util seq;
+        scoped_ptr_vector<eval> m_values;
+
+        struct str_update {
+            expr* e;
+            zstring value;
+            unsigned m_score;
+        };
+        vector<str_update> m_str_updates;
+        bool apply_str_update();
+        bool update(expr* e, zstring const& value);
+        
+        bool bval1(expr* e);
+        bool bval1_seq(app* e);
+        zstring& strval0(expr* e);
+        zstring const& strval1(expr* e);
+        
+        bool repair_contains(expr* e);
+    
+    public:
+        seq_plugin(context& c);
+        ~seq_plugin() override {}
+        expr_ref get_value(expr* e) override;
+        void initialize() override {}
+        void start_propagation() override {}
+        void propagate_literal(sat::literal lit) override;
+        bool propagate() override;
+        bool is_sat() override;
+        void register_term(expr* e) override;
+        std::ostream& display(std::ostream& out) const override;
+        bool set_value(expr* e, expr* v) override;
+        bool include_func_interp(func_decl* f) const override { return true; }
+
+        void repair_up(app* e) override;
+        bool repair_down(app* e) override;
+        void repair_literal(sat::literal lit) override;
+
+        void collect_statistics(statistics& st) const override {}
+        void reset_statistics() override {}
+
+    };
+    
+}