support c_embedding_grad for kunlun (#51399)

Author: QingshuChen

paddle/fluid/operators/collective/c_embedding_op_xpu.cc

@@ -71,6 +71,70 @@ class CEmbeddingOpXPUKernel : public framework::OpKernel<T> {
   }
 };
 
+template <typename DeviceContext, typename T>
+class CEmbeddingGradOpXPUKernel : public framework::OpKernel<T> {
+ public:
+  void Compute(const framework::ExecutionContext& context) const override {
+    const int64_t start_idx = context.Attr<int64_t>("start_index");
+    auto ids_t = context.Input<phi::DenseTensor>("Ids");
+    auto d_output_t =
+        context.Input<phi::DenseTensor>(framework::GradVarName("Out"));
+    auto table_t = context.Input<phi::DenseTensor>("W");
+    auto table_grad_t =
+        context.Output<phi::DenseTensor>(framework::GradVarName("W"));
+
+    T* table_grad_data =
+        table_grad_t->mutable_data<T>(table_t->dims(), context.GetPlace());
+
+    size_t table_t_mem_size =
+        table_t->numel() * phi::SizeOf(table_grad_t->dtype());
+    size_t table_grad_t_mem_size =
+        table_grad_t->numel() *
+        framework::SizeOfType(
+            framework::TransToProtoVarType(table_grad_t->dtype()));
+
+    VLOG(10) << "table_dims:" << table_t->dims()
+             << ", table_t memory_size:" << table_t_mem_size
+             << ", table_grad_t memory_size:" << table_grad_t_mem_size
+             << ", start_index:" << start_idx;
+
+    auto& dev_ctx = context.template device_context<DeviceContext>();
+    int r = xpu::constant(
+        dev_ctx.x_context(), table_grad_data, table_grad_t_mem_size, (T)0);
+    PADDLE_ENFORCE_XDNN_SUCCESS(r, "constant");
+    const T* d_output_data = d_output_t->data<T>();
+
+    const int64_t height = table_t->dims()[0];
+    const int64_t width = table_t->dims()[1];
+
+    const auto& index_type = framework::TransToProtoVarType(ids_t->dtype());
+    if (index_type == framework::proto::VarType::INT32) {
+      r = xpu::embedding_grad(dev_ctx.x_context(),
+                              d_output_data,
+                              ids_t->data<int32_t>(),
+                              table_grad_data,
+                              height,
+                              width,
+                              ids_t->numel(),
+                              -1,
+                              static_cast<int32_t>(start_idx));
+    } else if (index_type == framework::proto::VarType::INT64) {
+      r = xpu::embedding_grad(dev_ctx.x_context(),
+                              d_output_data,
+                              ids_t->data<int64_t>(),
+                              table_grad_data,
+                              height,
+                              width,
+                              ids_t->numel(),
+                              -1,
+                              static_cast<int64_t>(start_idx));
+    } else {
+      PADDLE_THROW(platform::errors::Unavailable(
+          "XPU c_embedding ids only support int32 or int64."));
+    }
+  }
+};
+
 }  // namespace operators
 }  // namespace paddle
 
@@ -80,3 +144,6 @@ namespace plat = paddle::platform;
 REGISTER_OP_XPU_KERNEL(
     c_embedding,
     ops::CEmbeddingOpXPUKernel<paddle::platform::XPUDeviceContext, float>);
+REGISTER_OP_XPU_KERNEL(
+    c_embedding_grad,
+    ops::CEmbeddingGradOpXPUKernel<paddle::platform::XPUDeviceContext, float>);

paddle/phi/backends/xpu/xpu2_op_list.cc

@@ -97,6 +97,7 @@ XPUOpMap& get_kl2_ops() {
       {"c_concat",
        XPUKernelSet({phi::DataType::FLOAT16, phi::DataType::FLOAT32})},
       {"c_embedding", XPUKernelSet({phi::DataType::FLOAT32})},
+      {"c_embedding_grad", XPUKernelSet({phi::DataType::FLOAT32})},
       {"c_identity",
        XPUKernelSet({phi::DataType::FLOAT16,
                      phi::DataType::FLOAT32,