Add functions to extract data pointer in specific memory spaces from ArrayView

Author: klevzoff

examples/exampleArrayOfArrays.cpp

@@ -279,14 +279,14 @@ TEST( ArrayOfArrays, resizeFromCapacities )
 // Sphinx start after ChaiBuffer
 CUDA_TEST( ArrayOfArrays, ChaiBuffer )
 {
-  LvArray::ArrayOfArrays< int, std::ptrdiff_t, LvArray::MallocBuffer > arrayOfArrays( 10, 9 );
+  LvArray::ArrayOfArrays< int, std::ptrdiff_t, LvArray::ChaiBuffer > arrayOfArrays( 10, 9 );
 
   {
     // Create a view.
     LvArray::ArrayOfArraysView< int,
                                 std::ptrdiff_t const,
                                 false,
-                                LvArray::MallocBuffer > const view = arrayOfArrays.toView();
+                                LvArray::ChaiBuffer > const view = arrayOfArrays.toView();
 
     // Capture the view on device. This will copy the values, sizes and offsets.
     // The values and sizes will be touched.
@@ -307,7 +307,7 @@ CUDA_TEST( ArrayOfArrays, ChaiBuffer )
     LvArray::ArrayOfArraysView< int,
                                 std::ptrdiff_t const,
                                 true,
-                                LvArray::MallocBuffer > const viewConstSizes = arrayOfArrays.toViewConstSizes();
+                                LvArray::ChaiBuffer > const viewConstSizes = arrayOfArrays.toViewConstSizes();
 
     // Capture the view on the host. This will copy back the values and sizes since they were previously touched
     // on device. It will only touch the values on host.
@@ -328,7 +328,7 @@ CUDA_TEST( ArrayOfArrays, ChaiBuffer )
     LvArray::ArrayOfArraysView< int const,
                                 std::ptrdiff_t const,
                                 true,
-                                LvArray::MallocBuffer > const viewConst = arrayOfArrays.toViewConst();
+                                LvArray::ChaiBuffer > const viewConst = arrayOfArrays.toViewConst();
 
     // Capture the view on device. Since the values were previously touched on host it will copy them over.
     // Both the sizes and offsets are current on device so they are not copied over. Nothing is touched.

src/ArrayView.hpp

@@ -427,6 +427,14 @@ class ArrayView
   T * data() const
   { return m_dataBuffer.data(); }
 
+  /**
+   * @brief @return Return a pointer to the values in a particular memory space.
+   * @param space The target memory space.
+   */
+  LVARRAY_HOST_DEVICE inline constexpr
+  T * data( MemorySpace const space ) const
+  { return m_dataBuffer.data( space ); }
+
   /**
    * @return Return an iterator to the begining of the data.
    */

src/ChaiBuffer.hpp

@@ -49,6 +49,7 @@ static std::mutex chaiLock;
  * @return The chai::ExecutionSpace corresponding to @p space.
  * @param space The MemorySpace to convert.
  */
+LVARRAY_HOST_DEVICE
 inline chai::ExecutionSpace toChaiExecutionSpace( MemorySpace const space )
 {
   if( space == MemorySpace::NONE )
@@ -294,6 +295,18 @@ class ChaiBuffer
   T * data() const
   { return m_pointer; }
 
+  /**
+   * @brief @return Return a pointer to the beginning of the buffer in a particular memory space.
+   * @param space The target memory space.
+   */
+  LVARRAY_HOST_DEVICE inline
+  T * data( MemorySpace const space ) const
+  {
+    T * const ptr = static_cast< T * >( m_pointer_record->m_pointers[ internal::toChaiExecutionSpace( space ) ] );
+    LVARRAY_ERROR_IF( ptr == nullptr, "Buffer not allocated in memory space " << space );
+    return ptr;
+  }
+
   /**
    * @tparam INDEX_TYPE the type used to index into the values.
    * @return The value at position @p i .

src/MallocBuffer.hpp

@@ -152,6 +152,17 @@ class MallocBuffer : public bufferManipulation::VoidBuffer
   T * data() const
   { return m_data; }
 
+  /**
+   * @brief @return Return a pointer to the beginning of the buffer in a particular memory space.
+   * @param space The target memory space.
+   */
+  LVARRAY_HOST_DEVICE inline
+  T * data( MemorySpace const space ) const
+  {
+    LVARRAY_ERROR_IF_NE_MSG( space, MemorySpace::CPU, "Buffer does not support target memory space" );
+    return data();
+  }
+
   /**
    * @tparam INDEX_TYPE the type used to index into the values.
    * @return The value at position @p i .

src/StackBuffer.hpp

@@ -99,6 +99,17 @@ class StackBuffer : public bufferManipulation::VoidBuffer
   T * data() const
   { return const_cast< T * >( m_data ); }
 
+  /**
+   * @brief @return Return a pointer to the beginning of the buffer in a particular memory space.
+   * @param space The target memory space.
+   */
+  LVARRAY_HOST_DEVICE inline
+  T * data( MemorySpace const space ) const
+  {
+    LVARRAY_ERROR_IF_NE_MSG( space, MemorySpace::CPU, "Buffer does not support target memory space" );
+    return data();
+  }
+
   /**
    * @tparam INDEX_TYPE the type used to index into the values.
    * @return The value at position @p i .

unitTests/CMakeLists.txt

@@ -12,6 +12,7 @@ set(testSources
     testArrayView_copyConstructor.cpp
     testArrayView_defaultConstructor.cpp
     testArrayView_emptyMove.cpp
+    testArrayView_getPointerInSpace.cpp
     testArrayView_modifyInKernel.cpp
     testArrayView_modifyInMultipleKernels.cpp
     testArrayView_move.cpp

unitTests/testArrayView.hpp

@@ -471,6 +471,18 @@ class ArrayViewPolicyTest : public ArrayViewTest< typename ARRAY_POLICY_PAIR::fi
     ParentClass::checkFill( array );
   }
 
+  static void getPointerInSpace()
+  {
+    std::unique_ptr< ARRAY > array = ParentClass::sizedConstructor();
+    ViewTypeConst const & view = array->toViewConst();
+
+    EXPECT_EQ( view.data( MemorySpace::CPU ), view.data() );
+    view.move( RAJAHelper< POLICY >::space, false );
+    EXPECT_EQ( view.data( RAJAHelper< POLICY >::space ), view.data() );
+    view.move( MemorySpace::CPU, false );
+    EXPECT_EQ( view.data( MemorySpace::CPU ), view.data() );
+  }
+
 protected:
 
   template< typename ARRAY >

unitTests/testArrayView_getPointerInSpace.cpp

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2020, Lawrence Livermore National Security, LLC and LvArray contributors.
+ * All rights reserved.
+ * See the LICENSE file for details.
+ * SPDX-License-Identifier: (BSD-3-Clause)
+ */
+
+// Source includes
+#include "testArrayView.hpp"
+
+namespace LvArray
+{
+namespace testing
+{
+
+TYPED_TEST( ArrayViewPolicyTest, getPointerInSpace )
+{
+  this->getPointerInSpace();
+}
+
+} // namespace testing
+} // namespace LvArray
+
+// This is the default gtest main method. It is included for ease of debugging.
+int main( int argc, char * * argv )
+{
+  ::testing::InitGoogleTest( &argc, argv );
+  int const result = RUN_ALL_TESTS();
+  return result;
+}