Z3 sources

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

lib/used_symbols.h

@@ -0,0 +1,105 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    used_symbols.h
+
+Abstract:
+
+    Collect the symbols used in an expression.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2011-01-11.
+
+Revision History:
+
+--*/
+#ifndef _USED_SYMBOLS_H_
+#define _USED_SYMBOLS_H_
+
+#include"ast.h"
+#include"hashtable.h"
+#include"obj_hashtable.h"
+
+struct do_nothing_rename_proc {
+    symbol operator()(symbol const & s) const { return s; }
+};
+
+/**
+   \brief Functor for collecting the symbols used in an expression.
+*/
+template<typename RENAME_PROC=do_nothing_rename_proc>
+class used_symbols : public RENAME_PROC { 
+    typedef hashtable<symbol, symbol_hash_proc, symbol_eq_proc> symbol_set;
+
+    symbol_set          m_used;
+    obj_hashtable<expr> m_visited;
+    ptr_vector<expr>    m_todo;
+
+    void found(symbol const & s) { m_used.insert(RENAME_PROC::operator()(s)); }
+
+    void visit(expr * n) {
+        if (!m_visited.contains(n)) {
+            m_visited.insert(n);
+            m_todo.push_back(n);
+        }
+    }
+
+public:
+    used_symbols(RENAME_PROC const & p = RENAME_PROC()):
+        RENAME_PROC(p) {
+    }
+    
+    void operator()(expr * n, bool ignore_quantifiers = false) {
+        m_visited.reset();
+        m_used.reset();
+        m_todo.reset();
+        visit(n);
+        while (!m_todo.empty()) {
+            n = m_todo.back();
+            m_todo.pop_back();
+            unsigned j;
+            switch (n->get_kind()) {
+            case AST_APP:
+                found(to_app(n)->get_decl()->get_name());
+                j = to_app(n)->get_num_args();
+                while (j > 0) {
+                    --j;
+                    visit(to_app(n)->get_arg(j));
+                }
+                break;
+            case AST_QUANTIFIER:
+                if (!ignore_quantifiers) {
+                    found(to_quantifier(n)->get_qid());
+                    unsigned num_decls = to_quantifier(n)->get_num_decls();
+                    for (unsigned i = 0; i < num_decls; i++)
+                        found(to_quantifier(n)->get_decl_name(i));
+                    unsigned num_pats = to_quantifier(n)->get_num_patterns();
+                    for (unsigned i = 0; i < num_pats; i++)
+                        visit(to_quantifier(n)->get_pattern(i));
+                    unsigned num_no_pats = to_quantifier(n)->get_num_no_patterns();
+                    for (unsigned i = 0; i < num_no_pats; i++)
+                        visit(to_quantifier(n)->get_no_pattern(i));
+                    visit(to_quantifier(n)->get_expr());
+                }
+                break;
+            default:
+                break;
+            }
+        }
+    }
+
+    bool contains(symbol const & s) const { return m_used.contains(RENAME_PROC::operator()(s)); }
+
+    bool contains_core(symbol const & s) const { return m_used.contains(s); }
+
+    void insert(symbol const & s) { m_used.insert(RENAME_PROC::operator()(s)); }
+    
+    void insert_core(symbol const & s) { m_used.insert(s); }
+
+    void erase_core(symbol const & s) { m_used.erase(s); }
+};
+
+#endif /* _USED_SYMBOLS_H_ */