Add auto detection for Metis integer type

Author: filikat

highs/ipm/hipo/auxiliary/AutoDetect.cpp

@@ -1,5 +1,10 @@
 #include "AutoDetect.h"
 
+#include <stdint.h>
+
+#define IDXTYPEWIDTH 64
+#include "metis.h"
+
 namespace hipo {
 
 extern "C" {
@@ -63,4 +68,34 @@ std::string getBlasIntegerModelString() {
   }
 }
 
+int getMetisIntegerType() {
+  idx_t options[METIS_NOPTIONS];
+  for (int i = 0; i < METIS_NOPTIONS; ++i) options[i] = -1;
+
+  // if Metis is using 32-bit internally, this should set ptype to 0 and objtype
+  // to 1, which should trigger an error. If it uses 64-bit then everything
+  // should be fine.
+  options[METIS_OPTION_PTYPE] = 1;
+
+  idx_t n = 3;
+  idx_t ptr[4] = {0, 2, 4, 6};
+  idx_t rows[6] = {1, 2, 0, 2, 0, 1};
+  idx_t perm[3], iperm[3];
+
+  idx_t status = METIS_NodeND(&n, ptr, rows, NULL, options, perm, iperm);
+
+  int metis_int = 0;
+  if (status == METIS_OK) {
+    if (perm[0] != 0 || perm[1] != 1 || perm[2] != 2)
+      metis_int = -1;
+    else
+      metis_int = 64;
+  } else if (status == METIS_ERROR_INPUT) {
+    metis_int = 32;
+  } else {
+    metis_int = -1;
+  }
+
+  return metis_int;
+}
 }  // namespace hipo

highs/ipm/hipo/auxiliary/AutoDetect.h

@@ -9,7 +9,8 @@ enum class BlasIntegerModel { not_set, unknown, lp64, ilp64 };
 BlasIntegerModel getBlasIntegerModel();
 std::string getBlasIntegerModelString();
 
-
+// Detect Metis integer type
+int getMetisIntegerType();
 
 }  // namespace hipo
 

highs/ipm/hipo/factorhighs/Analyse.cpp

@@ -1074,9 +1074,6 @@ void Analyse::reorderChildren() {
     // frontal size
     const Int64 fr = col_count_[sn_start_[sn]];
 
-    // very unlikely to happen
-    if (fr > int32_limit) return;
-
     // compute storage based on format used
     computeStorage(fr, sz, frontal_entries[sn], clique_entries[sn]);
 

highs/ipm/hipo/ipm/Solver.cpp

@@ -4,6 +4,7 @@
 #include <cmath>
 #include <iostream>
 
+#include "ipm/hipo/auxiliary/AutoDetect.h"
 #include "ipm/hipo/auxiliary/Log.h"
 #include "parallel/HighsParallel.h"
 
@@ -44,6 +45,8 @@ void Solver::solve() {
     return;
   }
 
+  if (checkMetis()) return;
+
   // iterate object needs to be initialised before potentially interrupting
   it_.reset(new Iterate(model_, regul_));
 
@@ -1082,6 +1085,21 @@ bool Solver::checkInterrupt() {
   return terminate;
 }
 
+bool Solver::checkMetis() {
+  Int metis_int = getMetisIntegerType();
+  if (metis_int == 32) {
+    logH_.printe("Metis should be compiled with 64-bit integers\n");
+    info_.status = kStatusError;
+    return true;
+  } else if (metis_int < 0) {
+    logH_.printe("Something went wrong checking Metis\n");
+    info_.status = kStatusError;
+    return true;
+  }
+
+  return false;
+}
+
 void Solver::printHeader() const {
   if (iter_ % 20 == 0) {
     std::stringstream log_stream;

highs/ipm/hipo/ipm/Solver.h

@@ -321,6 +321,11 @@ class Solver {
   // ===================================================================================
   bool checkInterrupt();
 
+  // ===================================================================================
+  // Check if Metis uses the correct integer type
+  // ===================================================================================
+  bool checkMetis();
+
   // ===================================================================================
   // Check if the current status has various properties.
   // ===================================================================================