Tpetra: Fixing Issue #13034 (#13036)

* Update Tpetra_Details_FixedHashTable_decl.hpp * Tpetra: Adding associated test * Update packages/tpetra/core/test/HashTable/FixedHashTableTest.cpp Co-authored-by: Tomasetti Romin <[email protected]> * Update packages/tpetra/core/src/Tpetra_Details_FixedHashTable_decl.hpp Co-authored-by: Tomasetti Romin <[email protected]> * Update Tpetra_Details_FixedHashTable_decl.hpp * Update packages/tpetra/core/src/Tpetra_Details_FixedHashTable_decl.hpp Co-authored-by: Tomasetti Romin <[email protected]> * Update FixedHashTableTest.cpp --------- Co-authored-by: Tomasetti Romin <[email protected]>
trilinos · Jun 7, 2024 · 0d278ca · 0d278ca
1 parent a6fd730
commit 0d278ca
Show file tree

Hide file tree

Showing 2 changed files with 14 additions and 7 deletions.
diff --git a/packages/tpetra/core/src/Tpetra_Details_FixedHashTable_decl.hpp b/packages/tpetra/core/src/Tpetra_Details_FixedHashTable_decl.hpp
@@ -429,9 +429,7 @@ class FixedHashTable {
   /// In Tpetra::Map, this corresponds to the maximum global index
   /// (local to the MPI process).
   /// @remark It will be set in @ref init.
-  KeyType maxKey_ = ::Kokkos::ArithTraits<KeyType>::is_integer ?
-                    ::Kokkos::ArithTraits<KeyType>::min() :
-                   -::Kokkos::ArithTraits<KeyType>::max();
+  KeyType maxKey_ = ::Kokkos::ArithTraits<KeyType>::max();
 
   /// \brief Minimum value.
   ///
@@ -461,9 +459,7 @@ class FixedHashTable {
   /// In that case, the initial contiguous sequence of keys may have
   /// length 1 or more.  Length 1 means that the sequence is trivial
   /// (there are no initial contiguous keys).
-  KeyType lastContigKey_ = ::Kokkos::ArithTraits<KeyType>::is_integer ?
-                           ::Kokkos::ArithTraits<KeyType>::min() :
-                          -::Kokkos::ArithTraits<KeyType>::max();
+  KeyType lastContigKey_ = ::Kokkos::ArithTraits<KeyType>::max();
 
   /// \brief Whether the table was created using one of the
   ///   constructors that assume contiguous values.

diff --git a/packages/tpetra/core/test/HashTable/FixedHashTableTest.cpp b/packages/tpetra/core/test/HashTable/FixedHashTableTest.cpp
@@ -1094,6 +1094,16 @@ namespace { // (anonymous)
     out << "Got to the end!" << endl;
   }
 
+//! @test Check that a default-initialized @ref FixedHashTable claims 0 pairs. This test was proposed in issue #13034.
+TEUCHOS_UNIT_TEST_TEMPLATE_3_DECL(FixedHashTable_T, ZeroPairsOnDefaultInit, ValueType, KeyType, DeviceType)
+  {
+    using fixed_hash_table_t = Tpetra::Details::FixedHashTable<KeyType,ValueType,DeviceType>;
+
+    fixed_hash_table_t table {};
+
+    TEST_EQUALITY_CONST(table.numPairs(), 0);
+  }
+
   //
   // Instantiations of the templated unit test(s) above.
   //
@@ -1116,7 +1126,8 @@ namespace { // (anonymous)
   TEUCHOS_UNIT_TEST_TEMPLATE_3_INSTANT( FixedHashTable_T, NoncontigKeysAndVals, LO, GO, DEVICE ) \
   TEUCHOS_UNIT_TEST_TEMPLATE_3_INSTANT( FixedHashTable_T, DuplicateKeys, LO, GO, DEVICE ) \
   TEUCHOS_UNIT_TEST_TEMPLATE_3_INSTANT( FixedHashTable_T, CopyCtorNoDupKeys, LO, GO, DEVICE ) \
-  TEUCHOS_UNIT_TEST_TEMPLATE_3_INSTANT( FixedHashTable_T, CopyCtorDupKeys, LO, GO, DEVICE )
+  TEUCHOS_UNIT_TEST_TEMPLATE_3_INSTANT( FixedHashTable_T, CopyCtorDupKeys, LO, GO, DEVICE ) \
+  TEUCHOS_UNIT_TEST_TEMPLATE_3_INSTANT( FixedHashTable_T, ZeroPairsOnDefaultInit, LO, GO, DEVICE )
 
   // The typedefs below are there because macros don't like arguments
   // with commas in them.