Do not call RENS/RINS when domain in already infeasible

ERGO-Code · Mar 3, 2025 · fb1da53 · fb1da53
1 parent 957c7ea
commit fb1da53
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Showing 2 changed files with 16 additions and 10 deletions.
diff --git a/src/mip/HighsMipSolver.cpp b/src/mip/HighsMipSolver.cpp
@@ -256,16 +256,19 @@ void HighsMipSolver::run() {
             analysis_.mipTimerStop(kMipClockRandomizedRounding0);
           }
 
-          if (mipdata_->incumbent.empty()) {
-            analysis_.mipTimerStart(kMipClockRens);
-            mipdata_->heuristics.RENS(
-                mipdata_->lp.getLpSolver().getSolution().col_value);
-            analysis_.mipTimerStop(kMipClockRens);
-          } else {
-            analysis_.mipTimerStart(kMipClockRins);
-            mipdata_->heuristics.RINS(
-                mipdata_->lp.getLpSolver().getSolution().col_value);
-            analysis_.mipTimerStop(kMipClockRins);
+          // previous heuristic may have detected infeasibility
+          if (!mipdata_->domain.infeasible()) {
+            if (mipdata_->incumbent.empty()) {
+              analysis_.mipTimerStart(kMipClockRens);
+              mipdata_->heuristics.RENS(
+                  mipdata_->lp.getLpSolver().getSolution().col_value);
+              analysis_.mipTimerStop(kMipClockRens);
+            } else {
+              analysis_.mipTimerStart(kMipClockRins);
+              mipdata_->heuristics.RINS(
+                  mipdata_->lp.getLpSolver().getSolution().col_value);
+              analysis_.mipTimerStop(kMipClockRins);
+            }
           }
 
           mipdata_->heuristics.flushStatistics();

diff --git a/src/mip/HighsSearch.cpp b/src/mip/HighsSearch.cpp
@@ -31,6 +31,9 @@ HighsSearch::HighsSearch(HighsMipSolver& mipsolver, HighsPseudocost& pseudocost)
   countTreeWeight = true;
   childselrule = mipsolver.submip ? ChildSelectionRule::kHybridInferenceCost
                                   : ChildSelectionRule::kRootSol;
+  // the infeasibility flag is overwritten and lost when setDomainChangeStack is
+  // called. therefore, assume that localdom is not infeasible here.
+  assert(!this->localdom.infeasible());
   this->localdom.setDomainChangeStack(std::vector<HighsDomainChange>());
 }