making var_eqs into a template

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>

src/util/lp/CMakeLists.txt

@@ -39,7 +39,6 @@ z3_add_component(lp
     square_dense_submatrix.cpp
     square_sparse_matrix.cpp
     static_matrix.cpp
-    var_eqs.cpp
   COMPONENT_DEPENDENCIES
     util
     polynomial

src/util/lp/emonomials.cpp

@@ -399,5 +399,4 @@ std::ostream& emonomials::display(std::ostream& out) const {
      return out;
  }
 
-
 }

src/util/lp/emonomials.h

@@ -29,7 +29,7 @@ namespace nla {
 
 class core;
 
-class emonomials : public var_eqs_merge_handler {
+class emonomials {
     /**
        \brief singly-lined cyclic list of monomial indices where variable occurs.
        Each variable points to the head and tail of the cyclic list.
@@ -75,7 +75,7 @@ class emonomials : public var_eqs_merge_handler {
     };
 
     mutable svector<lpvar>            m_find_key; // the key used when looking for a monomial with the specific variables
-    var_eqs&                        m_ve;
+    var_eqs<emonomials>&                        m_ve;
     mutable vector<monomial>        m_monomials;     // set of monomials
     mutable unsigned_vector         m_var2index;     // var_mIndex -> mIndex
     unsigned_vector                 m_lim;           // backtracking point
@@ -110,7 +110,7 @@ public:
        push and pop on emonomials calls push/pop on var_eqs, so no 
        other calls to push/pop to the var_eqs should take place. 
     */
-    emonomials(var_eqs& ve): 
+    emonomials(var_eqs<emonomials>& ve): 
         m_ve(ve), 
         m_visited(0), 
         m_cg_hash(*this),
@@ -288,11 +288,11 @@ public:
        these are merge event handlers to interect the union-find handlers.
        r2 becomes the new root. r2 is the root of v2, r1 is the old root of v1
     */
-    void merge_eh(signed_var r2, signed_var r1, signed_var v2, signed_var v1) override;
+    void merge_eh(signed_var r2, signed_var r1, signed_var v2, signed_var v1);
 
-    void after_merge_eh(signed_var r2, signed_var r1, signed_var v2, signed_var v1) override;
+    void after_merge_eh(signed_var r2, signed_var r1, signed_var v2, signed_var v1);
 
-    void unmerge_eh(signed_var r2, signed_var r1) override;        
+    void unmerge_eh(signed_var r2, signed_var r1);        
 
     bool is_monomial_var(lpvar v) const { return m_var2index.get(v, UINT_MAX) != UINT_MAX; }
 };

src/util/lp/nla_core.h

@@ -76,7 +76,7 @@ public:
 
 class core {
 public:
-    var_eqs                  m_evars;
+    var_eqs<emonomials>      m_evars;
     lp::lar_solver&          m_lar_solver;
     vector<lemma> *          m_lemma_vec;
     svector<lpvar>           m_to_refine;

src/util/lp/var_eqs.cpp

@@ -1,189 +0,0 @@
-/*++
-  Copyright (c) 2017 Microsoft Corporation
-
-  Module Name:
-
-  <name>
-
-  Abstract:
-
-  <abstract>
-
-  Author:
-  Nikolaj Bjorner (nbjorner)
-  Lev Nachmanson (levnach)
-
-  Revision History:
-
-
-  --*/
-
-#include "util/lp/var_eqs.h"
-
-namespace nla {
-    
-
-var_eqs::var_eqs(): m_merge_handler(nullptr), m_uf(*this), m_stack(*this) {}
-    
-void var_eqs::push() {
-    m_trail_lim.push_back(m_trail.size());
-    m_stack.push_scope();
-}
-
-void var_eqs::pop(unsigned n) {
-    unsigned old_sz = m_trail_lim[m_trail_lim.size() - n];
-    for (unsigned i = m_trail.size(); i-- > old_sz; ) {
-        auto const& sv = m_trail[i];
-        m_eqs[sv.first.index()].pop_back();
-        m_eqs[sv.second.index()].pop_back();
-        m_eqs[(~sv.first).index()].pop_back();
-        m_eqs[(~sv.second).index()].pop_back();
-    }
-    m_trail_lim.shrink(m_trail_lim.size() - n);
-    m_trail.shrink(old_sz);
-    m_stack.pop_scope(n);
-}
-
-void var_eqs::merge(signed_var v1, signed_var v2, eq_justification const& j) {
-    unsigned max_i = std::max(v1.index(), v2.index()) + 2;
-    m_eqs.reserve(max_i);
-    while (m_uf.get_num_vars() <= max_i) m_uf.mk_var();
-    m_trail.push_back(std::make_pair(v1, v2));
-    m_uf.merge(v1.index(), v2.index());
-    m_uf.merge((~v1).index(), (~v2).index());
-    m_eqs[v1.index()].push_back(eq_edge(v2, j));
-    m_eqs[v2.index()].push_back(eq_edge(v1, j));
-    m_eqs[(~v1).index()].push_back(eq_edge(~v2, j));
-    m_eqs[(~v2).index()].push_back(eq_edge(~v1, j));
-}
-
-signed_var var_eqs::find(signed_var v) const {
-    if (v.index() >= m_uf.get_num_vars()) {
-        return v;
-    }
-    unsigned idx = m_uf.find(v.index());
-    return signed_var(idx);
-}
-
-void var_eqs::explain_dfs(signed_var v1, signed_var v2, lp::explanation& e) const {
-    SASSERT(find(v1) == find(v2));
-    if (v1 == v2) {
-        return;
-    }
-    m_todo.push_back(var_frame(v1, 0));
-    m_justtrail.reset();
-    m_marked.reserve(m_eqs.size(), false);
-    SASSERT(m_marked_trail.empty());
-    m_marked[v1.index()] = true;
-    m_marked_trail.push_back(v1.index());
-    while (true) {
-        SASSERT(!m_todo.empty());
-        var_frame& f = m_todo.back();
-        signed_var v = f.m_var;
-        if (v == v2) {
-            break;
-        }
-        auto const& next = m_eqs[v.index()];
-        bool seen_all = true;
-        unsigned sz = next.size();
-        for (unsigned i = f.m_index; seen_all && i < sz; ++i) {
-            eq_edge const& jv = next[i];
-            signed_var v3 = jv.m_var;
-            if (!m_marked[v3.index()]) {
-                seen_all = false;
-                f.m_index = i + 1;
-                m_todo.push_back(var_frame(v3, 0));
-                m_justtrail.push_back(jv.m_just);
-                m_marked_trail.push_back(v3.index());
-                m_marked[v3.index()] = true;
-            }
-        }
-        if (seen_all) {
-            m_todo.pop_back();
-            m_justtrail.pop_back();
-        }
-    }
-        
-    for (eq_justification const& j : m_justtrail) {
-        j.explain(e);
-    }
-    m_stats.m_num_explains += m_justtrail.size();
-    m_stats.m_num_explain_calls++;
-    m_todo.reset();
-    m_justtrail.reset();
-    for (unsigned idx : m_marked_trail) {
-        m_marked[idx] = false;
-    }
-    m_marked_trail.reset();
-
-    // IF_VERBOSE(2, verbose_stream() << (double)m_stats.m_num_explains / m_stats.m_num_explain_calls << "\n");
-}
-
-void var_eqs::explain_bfs(signed_var v1, signed_var v2, lp::explanation& e) const {
-    SASSERT(find(v1) == find(v2));
-    if (v1 == v2) {
-        return;
-    }
-    m_todo.push_back(var_frame(v1, 0));
-    m_justtrail.push_back(eq_justification({}));
-    m_marked.reserve(m_eqs.size(), false);
-    SASSERT(m_marked_trail.empty());
-    m_marked[v1.index()] = true;
-    m_marked_trail.push_back(v1.index());
-    unsigned head = 0;
-    for (; ; ++head) {
-        var_frame& f = m_todo[head];
-        signed_var v = f.m_var;
-        if (v == v2) {
-            break;
-        }
-        auto const& next = m_eqs[v.index()];
-        unsigned sz = next.size();
-        for (unsigned i = sz; i-- > 0; ) {
-            eq_edge const& jv = next[i];
-            signed_var v3 = jv.m_var;
-            if (!m_marked[v3.index()]) {
-                m_todo.push_back(var_frame(v3, head));
-                m_justtrail.push_back(jv.m_just);
-                m_marked_trail.push_back(v3.index());
-                m_marked[v3.index()] = true;
-            }
-        }
-    }
-        
-    while (head != 0) {
-        m_justtrail[head].explain(e);
-        head = m_todo[head].m_index;
-        ++m_stats.m_num_explains;
-    }
-    ++m_stats.m_num_explain_calls;
-        
-    m_todo.reset();
-    m_justtrail.reset();
-    for (unsigned idx : m_marked_trail) {
-        m_marked[idx] = false;
-    }
-    m_marked_trail.reset();
-
-    // IF_VERBOSE(2, verbose_stream() << (double)m_stats.m_num_explains / m_stats.m_num_explain_calls << "\n");
-}
-
-
-std::ostream& var_eqs::display(std::ostream& out) const {
-    m_uf.display(out);
-    unsigned idx = 0;
-    for (auto const& edges : m_eqs) {
-        if (!edges.empty()) {
-            auto v = signed_var(idx);
-            out << v << " root: " << find(v) << " : ";
-            for (auto const& jv : edges) {
-                out << jv.m_var << " ";
-            }
-            out << "\n";
-        }
-        ++idx;
-    }
-    return out;
-}
-
-}

src/util/lp/var_eqs.h

@@ -45,13 +45,7 @@ public:
     }
 };
 
-class var_eqs_merge_handler {
+template <typename T>
-public:
-    virtual void merge_eh(signed_var r2, signed_var r1, signed_var v2, signed_var v1) = 0;
-    virtual void after_merge_eh(signed_var r2, signed_var r1, signed_var v2, signed_var v1) = 0;
-    virtual void unmerge_eh(signed_var r2, signed_var r1) = 0;
-};
-
 class var_eqs {
     struct eq_edge {
         signed_var       m_var;
@@ -70,7 +64,7 @@ class var_eqs {
         stats() { memset(this, 0, sizeof(*this)); }
     };
 
-    var_eqs_merge_handler*  m_merge_handler;    
+    T*  m_merge_handler;    
     union_find<var_eqs>         m_uf;
     svector<std::pair<signed_var, signed_var>>    m_trail;
     unsigned_vector            m_trail_lim;
@@ -83,30 +77,61 @@ class var_eqs {
     mutable svector<eq_justification> m_justtrail;
         
     mutable stats m_stats;
-public:
+public:    
-    var_eqs();
+    var_eqs(): m_merge_handler(nullptr), m_uf(*this), m_stack(*this) {}    
-    
     /**
-       \brief push a scope
+       \brief push a scope    */
-    */
+    void push() {
-    void push();
+        m_trail_lim.push_back(m_trail.size());
+        m_stack.push_scope();
+    }
 
     /**
        \brief pop n scopes
     */
-    void pop(unsigned n);
+    void pop(unsigned n)  {
+        unsigned old_sz = m_trail_lim[m_trail_lim.size() - n];
+        for (unsigned i = m_trail.size(); i-- > old_sz; ) {
+            auto const& sv = m_trail[i];
+            m_eqs[sv.first.index()].pop_back();
+            m_eqs[sv.second.index()].pop_back();
+            m_eqs[(~sv.first).index()].pop_back();
+            m_eqs[(~sv.second).index()].pop_back();
+        }
+        m_trail_lim.shrink(m_trail_lim.size() - n);
+        m_trail.shrink(old_sz);
+        m_stack.pop_scope(n);
+    }
 
     /**
        \brief merge equivalence classes for v1, v2 with justification j
     */
-    void merge(signed_var v1, signed_var v2, eq_justification const& j);
+    void merge(signed_var v1, signed_var v2, eq_justification const& j)  {
+        unsigned max_i = std::max(v1.index(), v2.index()) + 2;
+        m_eqs.reserve(max_i);
+        while (m_uf.get_num_vars() <= max_i) m_uf.mk_var();
+        m_trail.push_back(std::make_pair(v1, v2));
+        m_uf.merge(v1.index(), v2.index());
+        m_uf.merge((~v1).index(), (~v2).index());
+        m_eqs[v1.index()].push_back(eq_edge(v2, j));
+        m_eqs[v2.index()].push_back(eq_edge(v1, j));
+        m_eqs[(~v1).index()].push_back(eq_edge(~v2, j));
+        m_eqs[(~v2).index()].push_back(eq_edge(~v1, j));
+    }
+
     void merge_plus(lpvar v1, lpvar v2, eq_justification const& j)  { merge(signed_var(v1, false), signed_var(v2, false), j); }
     void merge_minus(lpvar v1, lpvar v2, eq_justification const& j) { merge(signed_var(v1, false), signed_var(v2, true),  j); }
 
     /**
        \brief find equivalence class representative for v
     */
-    signed_var find(signed_var v) const;
+    signed_var find(signed_var v) const {
+        if (v.index() >= m_uf.get_num_vars()) {
+            return v;
+        }
+        unsigned idx = m_uf.find(v.index());
+        return signed_var(idx);
+    }
     
     inline signed_var find(lpvar j) const {
         return find(signed_var(j, false));        
@@ -132,8 +157,109 @@ public:
        \brief Returns eq_justifications for
        \pre find(v1) == find(v2)
     */
-    void explain_dfs(signed_var v1, signed_var v2, lp::explanation& e) const;
+    void explain_dfs(signed_var v1, signed_var v2, lp::explanation& e) const {
-    void explain_bfs(signed_var v1, signed_var v2, lp::explanation& e) const;
+        SASSERT(find(v1) == find(v2));
+        if (v1 == v2) {
+            return;
+        }
+        m_todo.push_back(var_frame(v1, 0));
+        m_justtrail.reset();
+        m_marked.reserve(m_eqs.size(), false);
+        SASSERT(m_marked_trail.empty());
+        m_marked[v1.index()] = true;
+        m_marked_trail.push_back(v1.index());
+        while (true) {
+            SASSERT(!m_todo.empty());
+            var_frame& f = m_todo.back();
+            signed_var v = f.m_var;
+            if (v == v2) {
+                break;
+            }
+            auto const& next = m_eqs[v.index()];
+            bool seen_all = true;
+            unsigned sz = next.size();
+            for (unsigned i = f.m_index; seen_all && i < sz; ++i) {
+                eq_edge const& jv = next[i];
+                signed_var v3 = jv.m_var;
+                if (!m_marked[v3.index()]) {
+                    seen_all = false;
+                    f.m_index = i + 1;
+                    m_todo.push_back(var_frame(v3, 0));
+                    m_justtrail.push_back(jv.m_just);
+                    m_marked_trail.push_back(v3.index());
+                    m_marked[v3.index()] = true;
+                }
+            }
+            if (seen_all) {
+                m_todo.pop_back();
+                m_justtrail.pop_back();
+            }
+        }
+        
+        for (eq_justification const& j : m_justtrail) {
+            j.explain(e);
+        }
+        m_stats.m_num_explains += m_justtrail.size();
+        m_stats.m_num_explain_calls++;
+        m_todo.reset();
+        m_justtrail.reset();
+        for (unsigned idx : m_marked_trail) {
+            m_marked[idx] = false;
+        }
+        m_marked_trail.reset();
+
+        // IF_VERBOSE(2, verbose_stream() << (double)m_stats.m_num_explains / m_stats.m_num_explain_calls << "\n");
+    }
+
+    void explain_bfs(signed_var v1, signed_var v2, lp::explanation& e) const {
+        SASSERT(find(v1) == find(v2));
+        if (v1 == v2) {
+            return;
+        }
+        m_todo.push_back(var_frame(v1, 0));
+        m_justtrail.push_back(eq_justification({}));
+        m_marked.reserve(m_eqs.size(), false);
+        SASSERT(m_marked_trail.empty());
+        m_marked[v1.index()] = true;
+        m_marked_trail.push_back(v1.index());
+        unsigned head = 0;
+        for (; ; ++head) {
+            var_frame& f = m_todo[head];
+            signed_var v = f.m_var;
+            if (v == v2) {
+                break;
+            }
+            auto const& next = m_eqs[v.index()];
+            unsigned sz = next.size();
+            for (unsigned i = sz; i-- > 0; ) {
+                eq_edge const& jv = next[i];
+                signed_var v3 = jv.m_var;
+                if (!m_marked[v3.index()]) {
+                    m_todo.push_back(var_frame(v3, head));
+                    m_justtrail.push_back(jv.m_just);
+                    m_marked_trail.push_back(v3.index());
+                    m_marked[v3.index()] = true;
+                }
+            }
+        }
+        
+        while (head != 0) {
+            m_justtrail[head].explain(e);
+            head = m_todo[head].m_index;
+            ++m_stats.m_num_explains;
+        }
+        ++m_stats.m_num_explain_calls;
+        
+        m_todo.reset();
+        m_justtrail.reset();
+        for (unsigned idx : m_marked_trail) {
+            m_marked[idx] = false;
+        }
+        m_marked_trail.reset();
+
+        // IF_VERBOSE(2, verbose_stream() << (double)m_stats.m_num_explains / m_stats.m_num_explain_calls << "\n");
+    }
+
 
     inline void explain(signed_var v1, signed_var v2, lp::explanation& e) const {
         explain_bfs(v1, v2, e);
@@ -176,10 +302,25 @@ public:
     eq_class equiv_class(lpvar v) { return equiv_class(signed_var(v, false)); }
 
 
-    std::ostream& display(std::ostream& out) const;
+    std::ostream& display(std::ostream& out) const {
+        m_uf.display(out);
+        unsigned idx = 0;
+        for (auto const& edges : m_eqs) {
+            if (!edges.empty()) {
+                auto v = signed_var(idx);
+                out << v << " root: " << find(v) << " : ";
+                for (auto const& jv : edges) {
+                    out << jv.m_var << " ";
+                }
+                out << "\n";
+            }
+            ++idx;
+        }
+        return out;
+    }
 
     // union find event handlers
-    void set_merge_handler(var_eqs_merge_handler* mh) { m_merge_handler = mh; }
+    void set_merge_handler(T* mh) { m_merge_handler = mh; }
     // this method is required by union_find
     trail_stack<var_eqs> & get_trail_stack() { return m_stack; }
 
@@ -203,6 +344,7 @@ public:
     }
 };  // end of var_eqs
 
-inline std::ostream& operator<<(var_eqs const& ve, std::ostream& out) { return ve.display(out); }
+template <typename T>
+std::ostream& operator<<(var_eqs<T> const& ve, std::ostream& out) { return ve.display(out); }
 
 }