Further refactoring ackermannization.

src/ackermannization/ackr_bound_probe.cpp

@@ -0,0 +1,77 @@
+/*++
+ Copyright (c) 2016 Microsoft Corporation
+
+ Module Name:
+
+  ackr_bound_probe.cpp
+
+ Abstract:
+
+
+ Author:
+
+ Mikolas Janota
+
+ Revision History:
+--*/
+#include"ackr_helper.h"
+#include"ackr_bound_probe.h"
+#include"ast_smt2_pp.h"
+
+/*
+  For each function f, calculate the number of its occurrences o_f and compute "o_f choose 2".
+  The probe then sums up these for all functions.
+  This upper bound might be crude because some congruence lemmas trivially simplify to true.
+*/
+class ackr_bound_probe : public probe {
+    struct proc {
+        typedef ackr_helper::fun2terms_map fun2terms_map;
+        typedef ackr_helper::app_set       app_set;
+        ast_manager&                 m_m;
+        fun2terms_map                m_fun2terms; // a map from functions to occurrences
+        ackr_helper                  m_ackr_helper;
+
+        proc(ast_manager & m) : m_m(m), m_ackr_helper(m) { }
+
+        ~proc() {
+            fun2terms_map::iterator it = m_fun2terms.begin();
+            const fun2terms_map::iterator end = m_fun2terms.end();
+            for (; it != end; ++it) dealloc(it->get_value());
+        }
+
+        void operator()(quantifier *) {}
+        void operator()(var *) {}
+        void operator()(app * a) {
+            if (a->get_num_args() == 0) return;
+            if (!m_ackr_helper.should_ackermannize(a)) return;
+            func_decl* const fd = a->get_decl();
+            app_set* ts = 0;
+            if (!m_fun2terms.find(fd, ts)) {
+                ts = alloc(app_set);
+                m_fun2terms.insert(fd, ts);
+            }
+            ts->insert(a);
+        }
+    };
+
+public:
+    ackr_bound_probe() {}
+
+    virtual result operator()(goal const & g) {
+        proc p(g.m());
+        unsigned sz = g.size();
+        expr_fast_mark1 visited;
+        for (unsigned i = 0; i < sz; i++) {
+            for_each_expr_core<proc, expr_fast_mark1, true, true>(p, visited, g.form(i));
+        }
+        const double total = ackr_helper::calculate_lemma_bound(p.m_fun2terms);
+        TRACE("ackr_bound_probe", tout << "total=" << total << std::endl;);
+        return result(total);
+    }
+
+    inline static unsigned n_choose_2(unsigned n) { return n & 1 ? (n * (n >> 1)) : (n >> 1) * (n - 1); }
+};
+
+probe * mk_ackr_bound_probe() {
+    return alloc(ackr_bound_probe);
+}