Z3 sources

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

lib/matcher.cpp

@@ -0,0 +1,81 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    matcher.cpp
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Leonardo de Moura (leonardo) 2008-02-02.
+
+Revision History:
+
+--*/
+#include"matcher.h"
+
+matcher::matcher(ast_manager & m):
+    m_manager(m) {
+}
+
+bool matcher::operator()(expr * e1, expr * e2, substitution & s) {
+    reset();
+    m_subst = &s;
+    m_todo.push_back(expr_pair(e1, e2));
+    while (!m_todo.empty()) {
+        expr_pair const & p = m_todo.back();
+        // if (m_cache.contains(p)) {
+        //    m_todo.pop_back();
+        //    continue;
+        // }
+
+        if (is_var(p.first)) {
+            expr_offset r;
+            if (m_subst->find(to_var(p.first), 0, r)) {
+                if (r.get_expr() != p.second)
+                    return false;
+            }
+            else {
+                m_subst->insert(to_var(p.first), 0, expr_offset(p.second, 1));
+            }
+            m_todo.pop_back();
+            continue;
+        }
+
+
+        if (is_var(p.second))
+            return false;
+
+        app * n1 = to_app(p.first);
+        app * n2 = to_app(p.second);
+
+        if (n1->get_decl() != n2->get_decl())
+            return false;
+
+        unsigned num_args1 = n1->get_num_args();
+        if (num_args1 != n2->get_num_args())
+            return false;
+
+        m_todo.pop_back();
+
+        if (num_args1 == 0)
+            continue;
+        
+        // m_cache.insert(p);
+        unsigned j = num_args1;
+        while (j > 0) {
+            --j;
+            m_todo.push_back(expr_pair(n1->get_arg(j), n2->get_arg(j)));
+        }
+    }
+    return true;
+}
+
+void matcher::reset() {
+    // m_cache.reset();
+    m_todo.reset();
+}