Make lpcutremoved thread safe

Author: Opt-Mucca

highs/mip/HighsCutPool.cpp

@@ -147,8 +147,9 @@ double HighsCutPool::getParallelism(HighsInt row1, HighsInt row2,
   return dotprod * rownormalization_[row1] * pool2.rownormalization_[row2];
 }
 
-void HighsCutPool::lpCutRemoved(HighsInt cut) {
+void HighsCutPool::lpCutRemoved(HighsInt cut, bool thread_safe) {
   numLps_[cut].fetch_add(-1, std::memory_order_relaxed);
+  if (thread_safe) return;
   if (matrix_.columnsLinked(cut)) {
     propRows.erase(std::make_pair(-1, cut));
     propRows.emplace(1, cut);

highs/mip/HighsCutPool.h

@@ -102,8 +102,13 @@ class HighsCutPool {
   bool isDuplicate(size_t hash, double norm, const HighsInt* Rindex,
                    const double* Rvalue, HighsInt Rlen, double rhs);
 
-  void resetAge(HighsInt cut) {
+  void resetAge(HighsInt cut, bool thread_safe = false) {
     if (ages_[cut] > 0) {
+      if (thread_safe) {
+        int16_t numLp = numLps_[cut].fetch_add(1, std::memory_order_relaxed);
+        if (numLp >= 0) numLps_[cut].fetch_add(-1, std::memory_order_relaxed);
+        return;
+      }
       if (matrix_.columnsLinked(cut)) {
         propRows.erase(std::make_pair(ages_[cut], cut));
         propRows.emplace(0, cut);
@@ -121,7 +126,7 @@ class HighsCutPool {
 
   void performAging(bool parallel_sepa = false);
 
-  void lpCutRemoved(HighsInt cut);
+  void lpCutRemoved(HighsInt cut, bool thread_safe = false);
 
   void addPropagationDomain(HighsDomain::CutpoolPropagation* domain) {
     propagationDomains.push_back(domain);

highs/mip/HighsDomain.cpp

@@ -2493,7 +2493,8 @@ bool HighsDomain::propagate() {
           for (HighsInt k = 0; k != numproprows; ++k) {
             HighsInt i = propagateinds[k];
             if (propRowNumChangedBounds_[k].first != 0) {
-              cutpoolprop.cutpool->resetAge(i);
+              cutpoolprop.cutpool->resetAge(
+                  i, mipsolver->mipdata_->parallelLockActive());
               HighsInt start = cutpoolprop.cutpool->getMatrix().getRowStart(i);
               HighsInt end = start + propRowNumChangedBounds_[k].first;
               for (HighsInt j = start; j != end && !infeasible_; ++j)

highs/mip/HighsLpRelaxation.cpp

@@ -530,7 +530,7 @@ void HighsLpRelaxation::removeObsoleteRows(bool notifyPool) {
       if (notifyPool) {
         assert(lprows[i].cutpool <= mipsolver.mipdata_->cutpools.size());
         mipsolver.mipdata_->cutpools[lprows[i].cutpool].lpCutRemoved(
-            lprows[i].index);
+            lprows[i].index, mipsolver.mipdata_->parallelLockActive());
       }
     }
   }
@@ -579,7 +579,7 @@ void HighsLpRelaxation::removeCuts() {
     if (lprows[i].origin == LpRow::Origin::kCutPool) {
       assert(lprows[i].cutpool <= mipsolver.mipdata_->cutpools.size());
       mipsolver.mipdata_->cutpools[lprows[i].cutpool].lpCutRemoved(
-          lprows[i].index);
+          lprows[i].index, mipsolver.mipdata_->parallelLockActive());
     }
   }
   lprows.resize(modelrows);
@@ -627,7 +627,7 @@ void HighsLpRelaxation::performAging(bool deleteRows) {
         deletemask[i] = 1;
         assert(lprows[i].cutpool <= mipsolver.mipdata_->cutpools.size());
         mipsolver.mipdata_->cutpools[lprows[i].cutpool].lpCutRemoved(
-            lprows[i].index);
+            lprows[i].index, mipsolver.mipdata_->parallelLockActive());
       }
     } else if (std::abs(lpsolver.getSolution().row_dual[i]) >
                lpsolver.getOptions().dual_feasibility_tolerance) {