[SYCL] Initial implementation of GHistIndexMatrix (#10045)

Co-authored-by: Dmitry Razdoburdin <>

tests/cpp/plugin/sycl_helpers.h

@@ -0,0 +1,30 @@
+/*!
+ * Copyright 2022-2024 XGBoost contributors
+ */
+#pragma once
+
+#include "../helpers.h"
+
+namespace xgboost::sycl {
+template<typename T, typename Container>
+void VerifySyclVector(const USMVector<T, MemoryType::shared>& sycl_vector,
+                      const Container& host_vector) {
+  ASSERT_EQ(sycl_vector.Size(), host_vector.size());
+
+  size_t size = sycl_vector.Size();
+  for (size_t i = 0; i < size; ++i) {
+    ASSERT_EQ(sycl_vector[i], host_vector[i]);
+  }
+}
+
+template<typename T, typename Container>
+void VerifySyclVector(const std::vector<T>& sycl_vector, const Container& host_vector) {
+  ASSERT_EQ(sycl_vector.size(), host_vector.size());
+
+  size_t size = sycl_vector.size();
+  for (size_t i = 0; i < size; ++i) {
+    ASSERT_EQ(sycl_vector[i], host_vector[i]);
+  }
+}
+
+}  // namespace xgboost::sycl