Fix gather, scatter op 0d tenor GPU error. (#50271)

paddle/phi/kernels/funcs/gather.cu.h

@@ -285,7 +285,8 @@ void GatherV2GradCUDAFunction(const DenseTensor* input,
 
   if (input->numel() == 0) return;
   int axis_index = axis;
-  int64_t input_index_dim_size = input_dim[axis_index];
+  int64_t input_index_dim_size =
+      index->dims().size() == 0 ? 1 : input_dim[axis_index];
 
   int64_t inner_dim_size = 1;
   int64_t outer_dim_size = 1;

paddle/phi/kernels/funcs/scatter.cu.h

@@ -182,11 +182,15 @@ template <typename T, typename IndexT = int>
 void GPUScatterGradForX(const phi::GPUContext& ctx,
                         const DenseTensor& index,
                         DenseTensor* output) {
-  int64_t index_size = index.dims()[0];
+  int64_t index_size = index.dims().size() == 0 ? 1 : index.dims()[0];
   auto dst_dims = output->dims();
   // slice size
-  int64_t slice_size = 1;
-  for (int i = 1; i < dst_dims.size(); ++i) slice_size *= dst_dims[i];
+  int64_t slice_size = 1;  // slice size
+  if (index.dims().size() != 0) {
+    for (int i = 1; i < dst_dims.size(); ++i) slice_size *= dst_dims[i];
+  } else {
+    for (int i = 0; i < dst_dims.size(); ++i) slice_size *= dst_dims[i];
+  }
   const IndexT* p_index = index.data<IndexT>();
   T* p_output = output->data<T>();
   const size_t& slice_bytes = slice_size * sizeof(T);

python/paddle/fluid/tests/unittests/test_zero_dim_tensor.py

@@ -887,7 +887,7 @@ class TestSundryAPI(unittest.TestCase):
         self.assertEqual(x.grad.shape, [2, 3])
         self.assertEqual(out.grad.shape, [3])
 
-    def _test_gather_xD_axis_1(self):
+    def test_gather_xD_axis_1(self):
         x = paddle.to_tensor(
             [[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]], stop_gradient=False
         )
@@ -901,7 +901,7 @@ class TestSundryAPI(unittest.TestCase):
         self.assertEqual(x.grad.shape, [2, 3])
         self.assertEqual(out.grad.shape, [2])
 
-    def _test_scatter_1D(self):
+    def test_scatter_1D(self):
         x = paddle.to_tensor([1.0, 3.0, 5.0, 7.0, 9.0], stop_gradient=False)
         index = paddle.full([], 2, 'int64')
         updates = paddle.full([], 4.0)
@@ -913,7 +913,7 @@ class TestSundryAPI(unittest.TestCase):
         self.assertEqual(out.numpy()[2], 4)
         self.assertEqual(out.grad.shape, [5])
 
-    def _test_scatter_XD(self):
+    def test_scatter_XD(self):
         x = paddle.to_tensor(
             [[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]], stop_gradient=False
         )
@@ -1925,7 +1925,7 @@ class TestSundryAPIStatic(unittest.TestCase):
         self.assertEqual(res[2].shape, (3,))
 
     @prog_scope()
-    def _test_gather_XD_axis_1(self):
+    def test_gather_XD_axis_1(self):
         x = paddle.full([2, 3], 1.0, 'float32')
         x.stop_gradient = False
         index = paddle.full([], 1, 'int64')
@@ -1940,7 +1940,7 @@ class TestSundryAPIStatic(unittest.TestCase):
         self.assertEqual(res[2].shape, (2,))
 
     @prog_scope()
-    def _test_scatter_1D(self):
+    def test_scatter_1D(self):
         x = paddle.full([10], 1.0, 'float32')
         x.stop_gradient = False
         index = paddle.full([], 2, 'int64')
@@ -1956,7 +1956,7 @@ class TestSundryAPIStatic(unittest.TestCase):
         self.assertEqual(res[2].shape, (10,))
 
     @prog_scope()
-    def _test_scatter_XD(self):
+    def test_scatter_XD(self):
         x = paddle.full([2, 3], 1.0, 'float32')
         x.stop_gradient = False
         index = paddle.full([], 1, 'int64')