Device dmatrix (#5420)

src/data/simple_dmatrix.cu

@@ -8,26 +8,20 @@
 #include <xgboost/data.h>
 #include "../common/random.h"
 #include "./simple_dmatrix.h"
-#include "../common/math.h"
 #include "device_adapter.cuh"
 
 namespace xgboost {
 namespace data {
 
-XGBOOST_DEVICE bool IsValid(float value, float missing) {
-  if (common::CheckNAN(value) || value == missing) {
-    return false;
-  }
-  return true;
-}
 
 template <typename AdapterBatchT>
 void CountRowOffsets(const AdapterBatchT& batch, common::Span<bst_row_t> offset,
                      int device_idx, float missing) {
+  IsValidFunctor is_valid(missing);
   // Count elements per row
   dh::LaunchN(device_idx, batch.Size(), [=] __device__(size_t idx) {
     auto element = batch.GetElement(idx);
-    if (IsValid(element.value, missing)) {
+    if (is_valid(element)) {
       atomicAdd(reinterpret_cast<unsigned long long*>(  // NOLINT
                     &offset[element.row_idx]),
                 static_cast<unsigned long long>(1));  // NOLINT
@@ -66,11 +60,12 @@ void CopyDataColumnMajor(AdapterT* adapter, common::Span<Entry> data,
       thrust::device_pointer_cast(row_ptr.data() + row_ptr.size()));
   auto d_temp_row_ptr = temp_row_ptr.data().get();
   size_t begin = 0;
+  IsValidFunctor is_valid(missing);
   for (auto size : host_column_sizes) {
     size_t end = begin + size;
     dh::LaunchN(device_idx, end - begin, [=] __device__(size_t idx) {
       const auto& e = batch.GetElement(idx + begin);
-      if (!IsValid(e.value, missing)) return;
+      if (!is_valid(e)) return;
       data[d_temp_row_ptr[e.row_idx]] = Entry(e.column_idx, e.value);
       d_temp_row_ptr[e.row_idx] += 1;
     });
@@ -79,15 +74,6 @@ void CopyDataColumnMajor(AdapterT* adapter, common::Span<Entry> data,
   }
 }
 
-struct IsValidFunctor : public thrust::unary_function<Entry, bool> {
-  explicit IsValidFunctor(float missing) : missing(missing) {}
-
-  float missing;
-  __device__ bool operator()(const Entry& x) const {
-    return IsValid(x.fvalue, missing);
-  }
-};
-
 // Here the data is already correctly ordered and simply needs to be compacted
 // to remove missing data
 template <typename AdapterT>