initial commit for interpolation

src/interp/iz3base.h

@@ -0,0 +1,107 @@
+/* Copyright 2011 Microsoft Research. */
+
+#ifndef IZ3BASE_H
+#define IZ3BASE_H
+
+#include "iz3mgr.h"
+#include "iz3scopes.h"
+
+/* Base class for interpolators. Includes an AST manager and a scoping
+   object as bases. */
+ 
+class iz3base : public iz3mgr, public scopes {
+
+ public:
+
+  /** Get the range in which an expression occurs. This is the
+      smallest subtree containing all occurrences of the
+      expression. */
+  range &ast_range(ast);
+
+  /** Get the scope of an expression. This is the set of tree nodes in
+      which all of the expression's symbols are in scope. */
+  range &ast_scope(ast);
+
+  /** Get the range of a symbol. This is the smallest subtree containing
+      all occurrences of the symbol. */ 
+  range &sym_range(symb);
+
+  /** Is an expression local (in scope in some frame)? */
+
+  bool is_local(ast node){
+    return !range_is_empty(ast_scope(node));
+  }
+
+  /** Simplify an expression */
+
+  ast simplify(ast);
+
+  /** Constructor */
+
+  iz3base(scoped_ptr<ast_manager> &_m_manager,
+	 const std::vector<ast> &_cnsts,
+	 const std::vector<int> &_parents,
+	 const std::vector<ast> &_theory)
+    : iz3mgr(_m_manager), scopes(_parents)  {
+    initialize(_cnsts,_parents,_theory);
+    weak = false;
+  }
+
+  /* Set our options */
+  void set_option(const std::string &name, const std::string &value){
+    if(name == "weak" && value == "1") weak = true;
+  }
+  
+  /* Are we doing weak interpolants? */
+  bool weak_mode(){return weak;}
+
+  /** Print interpolation problem to an SMTLIB format file */
+  void print(const std::string &filename);
+
+  /** Check correctness of a solutino to this problem. */
+  void check_interp(const std::vector<ast> &itps, std::vector<ast> &theory);
+
+  /** For convenience -- is this formula SAT? */
+  bool is_sat(ast);
+
+  /** Interpolator for clauses, to be implemented */
+  virtual void interpolate_clause(std::vector<ast> &lits, std::vector<ast> &itps){
+    throw "no interpolator";
+  }
+
+ private:
+
+  struct ranges {
+    range rng;
+    range scp;
+    bool scope_computed;
+    ranges(){scope_computed = false;}
+  };
+
+  stl_ext::hash_map<symb,range> sym_range_hash;
+  stl_ext::hash_map<ast,ranges> ast_ranges_hash;
+  stl_ext::hash_map<ast,ast> simplify_memo;
+
+
+  void add_frame_range(int frame, ast t);
+
+  void initialize(const std::vector<ast> &_parts, const std::vector<int> &_parents, const std::vector<ast> &_theory);
+
+  std::vector<ast> cnsts;
+
+  bool is_literal(ast n);
+  void gather_conjuncts_rec(ast n, std::vector<ast> &conjuncts, stl_ext::hash_set<ast> &memo);
+  void gather_conjuncts(ast n, std::vector<ast> &conjuncts);
+  ast simplify_and(std::vector<ast> &conjuncts);
+  ast simplify_with_lit_rec(ast n, ast lit, stl_ext::hash_map<ast,ast> &memo, int depth);
+  ast simplify_with_lit(ast n, ast lit);  
+
+  bool weak;
+
+};
+
+
+
+
+
+#endif