Deallocation of vector made more clear

Author: filikat

highs/ipm/hipo/auxiliary/Auxiliary.h

@@ -71,6 +71,14 @@ void printTest(const std::vector<T>& v, const std::string s) {
   out_file.close();
 }
 
+template <typename T>
+void freeVector(std::vector<T> v) {
+  // Give up memory allocated to v.
+  // (technically shrink_to_fit does not guarantee to deallocate)
+  v.clear();
+  v.shrink_to_fit();
+}
+
 class Clock {
   std::chrono::high_resolution_clock::time_point t0;
 

highs/ipm/hipo/factorhighs/Factorise.cpp

@@ -326,8 +326,7 @@ void Factorise::processSupernode(Int sn) {
 
     // Schur contribution of the child is no longer needed
     if (parallel) {
-      // Swap with temporary empty vector to deallocate memory
-      std::vector<double>().swap(schur_contribution_[child_sn]);
+      freeVector(schur_contribution_[child_sn]);
     } else {
       stack_->popChild();
     }

highs/ipm/hipo/ipm/FactorHiGHSSolver.cpp

@@ -728,24 +728,20 @@ void FactorHiGHSSolver::getReg(std::vector<double>& reg) {
 }
 
 void FactorHiGHSSolver::freeASmemory() {
-  // Swap AS data structures with empty vectors, to guarantee that memory is
-  // freed.
-
-  std::vector<Int>().swap(ptrAS_);
-  std::vector<Int>().swap(rowsAS_);
-  std::vector<double>().swap(valAS_);
+  // Give up memory used for AS.
+  freeVector(ptrAS_);
+  freeVector(rowsAS_);
+  freeVector(valAS_);
 }
 
 void FactorHiGHSSolver::freeNEmemory() {
-  // Swap NE data structures with empty vectors, to guarantee that memory is
-  // freed.
-
-  std::vector<Int>().swap(ptrNE_);
-  std::vector<Int>().swap(rowsNE_);
-  std::vector<double>().swap(valNE_);
-  std::vector<Int>().swap(ptrA_rw_);
-  std::vector<Int>().swap(idxA_rw_);
-  std::vector<Int>().swap(corr_A_);
+  // Give up memory used for NE.
+  freeVector(ptrNE_);
+  freeVector(rowsNE_);
+  freeVector(valNE_);
+  freeVector(ptrA_rw_);
+  freeVector(idxA_rw_);
+  freeVector(corr_A_);
 }
 
 }  // namespace hipo