1 files changed, 22 insertions, 24 deletions

diff --git a/impl/EquationSystem.hpp b/impl/EquationSystem.hpp
index ac0b3b2..772ac37 100644
--- a/impl/EquationSystem.hpp
+++ b/impl/EquationSystem.hpp
@@ -3,7 +3,13 @@
 
 #include <map>
 
+template<typename T>
+struct EquationSystem;
+
+#include "IdSet.hpp"
 #include "Expression.hpp"
+#include "FixpointAlgorithm.hpp"
+
 template<typename T>
 struct MaxStrategy;
 
@@ -31,11 +37,14 @@ struct EquationSystem {
   const std::vector<Variable<T>*> vars() const {
     return _vars;
   }
+  const Variable<T>* getVar(unsigned int i) const {
+    return _vars[i];
+  }
   unsigned int varCount() const {
     return _vars.size();
   }
 
-  Expression<T>* newExpression(Operator<T>* op, const std::vector<Expression<T>*>& args) {
+  Expression<T>* newExpression(Operator<T>* op, const std::vector<Expression<T>*>& args=std::vector<Expression<T>*>()) {
     Expression<T>* expr = new Expression<T>(op, args);
     _expressions.push_back(expr);
     return expr;
@@ -58,7 +67,7 @@ struct EquationSystem {
   MaxStrategy<T> strategy() const {
     return MaxStrategy<T>(_max_expressions.size());
   }
-  
+
   VariableAssignment<T> assignment() const {
     return VariableAssignment<T>(_vars.size());
   }
@@ -69,7 +78,7 @@ struct EquationSystem {
     }
     return _right_expressions[v.id()];
   }
-  const Expression<T>*& operator[] (const Variable<T>& v) const {
+  const Expression<T>* operator[] (const Variable<T>& v) const {
     if (_right_expressions.size() <= v.id()) {
       throw "Out of range";
     }
@@ -95,38 +104,27 @@ struct EquationSystem {
 
   VariableAssignment<T> maxFixpoint() const {
     unsigned int size = _vars.size();
-    VariableAssignment<T> result(size, infinity<T>());
-    for (unsigned int i = 0; i < size; ++i) {
-      result = (*this)(result);
-    }
-    result = result.expand((*this)(result), -infinity<T>());
-    for (unsigned int i = 0; i < size-1; ++i) {
-      result = (*this)(result);
-    }
+    VariableAssignment<T> newResult(size, infinity<T>());
+    VariableAssignment<T> result(0);
+    do {
+      result = newResult;
+      newResult = (*this)(result);
+    } while (newResult != result);
     return result;
   }
 
-  VariableAssignment<T> maxFixpoint(const MaxStrategy<T>& strat) const {
-    unsigned int size = _vars.size();
-    VariableAssignment<T> result(size, infinity<T>());
-    for (unsigned int i = 0; i < size; ++i) {
-      result = strat(*this, result);
-    }
-    result = result.expand(strat(*this, result), -infinity<T>());
-    for (unsigned int i = 0; i < size-1; ++i) {
-      result = strat(*this, result);
-    }
-    return result;
+  VariableAssignment<T> maxFixpoint(const MaxStrategy<T>& strat, const FixpointAlgorithm<T>& algo) const {
+    return algo.maxFixpoint(strat, *this);
   }
 
-  VariableAssignment<T> minFixpoint() const {
+  VariableAssignment<T> minFixpoint(const FixpointAlgorithm<T>& algo) const {
     VariableAssignment<T> rho = assignment();
     VariableAssignment<T> lastRho = assignment();
     MaxStrategy<T> strat = strategy();
     do {
       lastRho = rho;
       strat = strat.improve(*this, rho);
-      rho = maxFixpoint(strat);
+      rho = maxFixpoint(strat, algo);
     } while(lastRho != rho);
     return rho;
   }