Purge device_helpers.cuh (#5534)

* Simplifications with caching_device_vector

* Purge device helpers

tests/cpp/common/test_device_helpers.cu

@@ -27,64 +27,13 @@ void CreateTestData(xgboost::bst_uint num_rows, int max_row_size,
   }
 }
 
-void TestLbs() {
-  srand(17);
-  dh::CubMemory temp_memory;
-
-  std::vector<int> test_rows = {4, 100, 1000};
-  std::vector<int> test_max_row_sizes = {4, 100, 1300};
-
-  for (auto num_rows : test_rows) {
-    for (auto max_row_size : test_max_row_sizes) {
-      thrust::host_vector<int> h_row_ptr;
-      thrust::host_vector<xgboost::bst_uint> h_rows;
-      CreateTestData(num_rows, max_row_size, &h_row_ptr, &h_rows);
-      thrust::device_vector<size_t> row_ptr = h_row_ptr;
-      thrust::device_vector<int> output_row(h_rows.size());
-      auto d_output_row = output_row.data();
-
-      dh::TransformLbs(0, &temp_memory, h_rows.size(), dh::Raw(row_ptr),
-                       row_ptr.size() - 1, false,
-                       [=] __device__(size_t idx, size_t ridx) {
-                         d_output_row[idx] = ridx;
-                       });
-
-      dh::safe_cuda(cudaDeviceSynchronize());
-      ASSERT_TRUE(h_rows == output_row);
-    }
-  }
-}
-
-TEST(CubLBS, Test) {
-  TestLbs();
-}
-
 TEST(SumReduce, Test) {
   thrust::device_vector<float> data(100, 1.0f);
   dh::CubMemory temp;
-  auto sum = dh::SumReduction(&temp, dh::Raw(data), data.size());
+  auto sum = dh::SumReduction(&temp, data.data().get(), data.size());
   ASSERT_NEAR(sum, 100.0f, 1e-5);
 }
 
-void TestAllocator() {
-  int n = 10;
-  Span<float> a;
-  Span<int> b;
-  Span<size_t> c;
-  dh::BulkAllocator ba;
-  ba.Allocate(0, &a, n, &b, n, &c, n);
-
-  // Should be no illegal memory accesses
-  dh::LaunchN(0, n, [=] __device__(size_t idx) { c[idx] = a[idx] + b[idx]; });
-
-  dh::safe_cuda(cudaDeviceSynchronize());
-}
-
-// Define the test in a function so we can use device lambda
-TEST(BulkAllocator, Test) {
-  TestAllocator();
-}
-
 template <typename T, typename Comp = thrust::less<T>>
 void TestUpperBoundImpl(const std::vector<T> &vec, T val_to_find,
                         const Comp &comp = Comp()) {