Z3 sources

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

lib/cached_var_subst.cpp

@@ -0,0 +1,79 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    cached_var_subst.cpp
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Leonardo de Moura (leonardo) 2009-01-23.
+
+Revision History:
+
+--*/
+#include"cached_var_subst.h"
+
+bool cached_var_subst::key_eq_proc::operator()(cached_var_subst::key * k1, cached_var_subst::key * k2) const {
+    if (k1->m_qa != k2->m_qa)
+        return false;
+    if (k1->m_num_bindings != k2->m_num_bindings)
+        return false;
+    for (unsigned i = 0; i < k1->m_num_bindings; i++) 
+        if (k1->m_bindings[i] != k2->m_bindings[i])
+            return false;
+    return true;
+}
+
+cached_var_subst::cached_var_subst(ast_manager & m):
+    m_proc(m),
+    m_refs(m) {
+}
+
+void cached_var_subst::reset() {
+    m_refs.reset();
+    m_instances.reset();
+    m_region.reset();
+    m_new_keys.reset();
+}
+
+void cached_var_subst::operator()(quantifier * qa, unsigned num_bindings, smt::enode * const * bindings, expr_ref & result) {
+    m_new_keys.reserve(num_bindings+1, 0);
+    key * new_key = m_new_keys[num_bindings];
+    if (new_key == 0)
+        new_key = static_cast<key*>(m_region.allocate(sizeof(key) + sizeof(expr*)*num_bindings));
+
+    new_key->m_qa           = qa;
+    new_key->m_num_bindings = num_bindings;
+    for (unsigned i = 0; i < num_bindings; i++) 
+        new_key->m_bindings[i] = bindings[i]->get_owner();
+    
+    instances::entry * entry = m_instances.insert_if_not_there2(new_key, 0);
+    if (entry->get_data().m_key != new_key) {
+        SASSERT(entry->get_data().m_value != 0);
+        // entry was already there
+        m_new_keys[num_bindings] = new_key; // recycle key
+        result = entry->get_data().m_value;
+        return;
+    }
+    
+    m_proc(qa->get_expr(), new_key->m_num_bindings, new_key->m_bindings, result);
+    // cache result
+    entry->get_data().m_value = result;
+
+    // remove key from cache
+    m_new_keys[num_bindings] = 0;
+    
+    // increment reference counters
+    m_refs.push_back(qa);
+    for (unsigned i = 0; i < new_key->m_num_bindings; i++)
+        m_refs.push_back(new_key->m_bindings[i]);
+    m_refs.push_back(result);
+}
+
+
+