--- /dev/null
+#include <set>
+#include "graphSorting.hh"
+
+/**
+ * Set the order of a loop and place it to appropriate set
+ */
+static void setOrder(Loop* l, int order, lgraph& V)
+{
+ assert(l);
+ V.resize(order+1);
+ if (l->fOrder >= 0) { V[l->fOrder].erase(l); }
+ l->fOrder = order; V[order].insert(l);
+}
+
+/**
+ * Set the order of T1's loops and collect there sons into T2
+ */
+static void setLevel(int order, const lset& T1, lset& T2, lgraph& V)
+{
+ for (lset::const_iterator p = T1.begin(); p!=T1.end(); p++) {
+ setOrder(*p, order, V);
+ T2.insert((*p)->fBackwardLoopDependencies.begin(), (*p)->fBackwardLoopDependencies.end());
+ }
+}
+
+
+static void resetOrder(Loop* l)
+{
+ l->fOrder = -1;
+ for (lset::const_iterator p = l->fBackwardLoopDependencies.begin(); p!=l->fBackwardLoopDependencies.end(); p++) {
+ resetOrder(*p);
+ }
+}
+/**
+ * Topological sort of an acyclic graph of loops. The loops
+ * are collect in an lgraph : a vector of sets of loops
+ */
+void sortGraph(Loop* root, lgraph& V)
+{
+ lset T1, T2;
+ int level;
+
+ assert(root);
+ resetOrder(root);
+ T1.insert(root); level=0; V.clear();
+ do {
+ setLevel(level, T1, T2, V);
+ T1=T2; T2.clear(); level++;
+ } while (T1.size()>0);
+
+ // Erase empty levels
+ lgraph::iterator p = V.begin();
+ while (p != V.end()) {
+ if ((*p).size() == 1 && (*(*p).begin())->isEmpty()) {
+ p = V.erase(p);
+ } else {
+ p++;
+ }
+ }
+}