Make pad2d support for variable paddings. (#14667)

* Make pad2d support for variable paddings.
test=develop

* Rename get_paddings and add inline modifier.
test=develop

* Fix comments.

paddle/fluid/operators/pad2d_op.cc

@@ -319,20 +319,46 @@ void Pad2DGradEdgeNHWC(T* d_in_data, const int num, const int channels,
   }
 }
 
+static inline void GetPaddings(int* paddings,
+                               const framework::ExecutionContext& context) {
+  auto* paddings_t = context.Input<Tensor>("Paddings");
+  if (paddings_t) {
+    auto paddings_data = paddings_t->data<int>();
+    paddings[0] = paddings_data[0];
+    paddings[1] = paddings_data[1];
+    paddings[2] = paddings_data[2];
+    paddings[3] = paddings_data[3];
+  } else {
+    auto pads = context.Attr<std::vector<int>>("paddings");
+    std::copy(pads.begin(), pads.end(), paddings);
+  }
+}
+
 template <typename T>
 class Pad2dCPUKernel : public framework::OpKernel<T> {
  public:
   void Compute(const framework::ExecutionContext& context) const override {
-    auto pads = context.Attr<std::vector<int>>("paddings");
+    int pads[4];
+    GetPaddings(pads, context);
     auto mode = context.Attr<std::string>("mode");
     auto data_format = context.Attr<std::string>("data_format");
     T value = context.Attr<T>("pad_value");
+
     auto* x = context.Input<Tensor>("X");
-    auto* out = context.Output<Tensor>("Out");
     auto in_dims = x->dims();
-    auto out_dims = out->dims();
     const T* in_data = x->data<T>();
+
+    auto* out = context.Output<Tensor>("Out");
+    if (data_format == "NCHW") {
+      out->Resize({in_dims[0], in_dims[1], in_dims[2] + pads[0] + pads[1],
+                   in_dims[3] + pads[2] + pads[3]});
+    } else {
+      out->Resize({in_dims[0], in_dims[1] + pads[0] + pads[1],
+                   in_dims[2] + pads[2] + pads[3], in_dims[3]});
+    }
+    auto out_dims = out->dims();
     T* out_data = out->mutable_data<T>(context.GetPlace());
+
     const int pad_top = pads[0];
     const int pad_left = pads[2];
     const int num = in_dims[0];
@@ -376,7 +402,8 @@ template <typename T>
 class Pad2dGradCPUKernel : public framework::OpKernel<T> {
  public:
   void Compute(const framework::ExecutionContext& context) const override {
-    auto pads = context.Attr<std::vector<int>>("paddings");
+    int pads[4];
+    GetPaddings(pads, context);
     auto mode = context.Attr<std::string>("mode");
     auto data_format = context.Attr<std::string>("data_format");
     auto* d_out = context.Input<Tensor>(framework::GradVarName("Out"));
@@ -442,21 +469,35 @@ class Pad2dOp : public framework::OperatorWithKernel {
                    "Output(Out) of Pad2dOp should not be null.");
 
     auto x_dim = ctx->GetInputDim("X");
-    auto paddings = ctx->Attrs().Get<std::vector<int>>("paddings");
     PADDLE_ENFORCE_EQ(x_dim.size(), 4,
-                      "Size of paddings should be equal to 4.");
-    std::vector<int64_t> out_dims(x_dim.size());
+                      "The size of input(X)'s dimension should be equal to 4.");
 
+    std::vector<int64_t> out_dims(x_dim.size());
     auto data_format = ctx->Attrs().Get<std::string>("data_format");
     out_dims[0] = x_dim[0];
-    if (data_format == "NCHW") {
+    if (ctx->HasInput("Paddings")) {
+      auto paddings_dim = ctx->GetInputDim("Paddings");
+      PADDLE_ENFORCE_EQ(
+          paddings_dim.size(), 1,
+          "Size of Input(Paddings)'s dimension should be equal to 1.");
+      PADDLE_ENFORCE_EQ(paddings_dim[0], 4,
+                        "Shape of Input(Paddings) should be equal to [4].");
       out_dims[1] = x_dim[1];
-      out_dims[2] = x_dim[2] + paddings[0] + paddings[1];  // height
-      out_dims[3] = x_dim[3] + paddings[2] + paddings[3];  // width
-    } else {                                               // NHWC
+      out_dims[2] = x_dim[2];
       out_dims[3] = x_dim[3];
-      out_dims[1] = x_dim[1] + paddings[0] + paddings[1];
-      out_dims[2] = x_dim[2] + paddings[2] + paddings[3];
+    } else {
+      auto paddings = ctx->Attrs().Get<std::vector<int>>("paddings");
+      PADDLE_ENFORCE_EQ(paddings.size(), 4,
+                        "Size of paddings should be equal to 4.");
+      if (data_format == "NCHW") {
+        out_dims[1] = x_dim[1];
+        out_dims[2] = x_dim[2] + paddings[0] + paddings[1];  // height
+        out_dims[3] = x_dim[3] + paddings[2] + paddings[3];  // width
+      } else {                                               // NHWC
+        out_dims[3] = x_dim[3];
+        out_dims[1] = x_dim[1] + paddings[0] + paddings[1];
+        out_dims[2] = x_dim[2] + paddings[2] + paddings[3];
+      }
     }
 
     ctx->SetOutputDim("Out", framework::make_ddim(out_dims));
@@ -466,6 +507,13 @@ class Pad2dOp : public framework::OperatorWithKernel {
       ctx->ShareLoD("X", /*->*/ "Out");
     }
   }
+
+ protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        framework::ToDataType(ctx.Input<Tensor>("X")->type()), ctx.GetPlace());
+  }
 };
 
 class Pad2dOpMaker : public framework::OpProtoAndCheckerMaker {
@@ -477,6 +525,12 @@ class Pad2dOpMaker : public framework::OpProtoAndCheckerMaker {
     AddOutput("Out",
               "The output of pad2d op. "
               "A tensor with the same shape as X.");
+    AddInput("Paddings",
+             "A 1-D tensor to describe the padding rules."
+             "paddings=[0, 1, 2, 3] means "
+             "padding 0 row to top, 1 row to bottom, 2 columns to left "
+             "and 3 columns to right. Size of paddings must be 4.")
+        .AsDispensable();
     AddAttr<std::vector<int>>(
         "paddings",
         "(vector<int>) "
@@ -554,6 +608,13 @@ class Pad2dOpGrad : public framework::OperatorWithKernel {
       ctx->SetOutputDim(x_grad_name, x_dims);
     }
   }
+
+ protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        framework::ToDataType(ctx.Input<Tensor>("X")->type()), ctx.GetPlace());
+  }
 };
 
 class Pad2dOpGradMaker : public framework::SingleGradOpDescMaker {
@@ -564,6 +625,7 @@ class Pad2dOpGradMaker : public framework::SingleGradOpDescMaker {
   std::unique_ptr<framework::OpDesc> Apply() const override {
     auto* bind = new framework::OpDesc();
     bind->SetInput("X", Input("X"));
+    bind->SetInput("Paddings", Input("Paddings"));
     bind->SetInput(framework::GradVarName("Out"), OutputGrad("Out"));
     bind->SetOutput(framework::GradVarName("X"), InputGrad("X"));
     bind->SetAttrMap(Attrs());

paddle/fluid/operators/pad2d_op.cu

@@ -287,20 +287,50 @@ __global__ void Pad2DGradEdgeNHWC(const int out_size, T* d_in_data,
   }
 }
 
+static inline void GetPaddings(int* paddings,
+                               const framework::ExecutionContext& context) {
+  auto* paddings_t = context.Input<Tensor>("Paddings");
+  if (paddings_t) {
+    Tensor pads;
+    framework::TensorCopySync(*paddings_t, platform::CPUPlace(), &pads);
+    auto pads_data = pads.data<int>();
+    paddings[0] = pads_data[0];
+    paddings[1] = pads_data[1];
+    paddings[2] = pads_data[2];
+    paddings[3] = pads_data[3];
+  } else {
+    auto pads = context.Attr<std::vector<int>>("paddings");
+    std::copy(pads.begin(), pads.end(), paddings);
+  }
+}
+
 template <typename T>
 class Pad2dCUDAKernel : public framework::OpKernel<T> {
  public:
   void Compute(const framework::ExecutionContext& context) const override {
-    auto pads = context.Attr<std::vector<int>>("paddings");
+    int pads[4];
+    GetPaddings(pads, context);
     auto mode = context.Attr<std::string>("mode");
     auto data_format = context.Attr<std::string>("data_format");
     T value = context.Attr<T>("pad_value");
+
     auto* x = context.Input<Tensor>("X");
-    auto* out = context.Output<Tensor>("Out");
     auto in_dims = x->dims();
-    auto out_dims = out->dims();
     const T* in_data = x->data<T>();
-    T* out_data = out->mutable_data<T>(context.GetPlace());
+    auto* out = context.Output<Tensor>("Out");
+    auto out_dims = out->dims();
+    if (data_format == "NCHW") {
+      out_dims[0] = in_dims[0];
+      out_dims[1] = in_dims[1];
+      out_dims[2] = in_dims[2] + pads[0] + pads[1];
+      out_dims[3] = in_dims[3] + pads[2] + pads[3];
+    } else {
+      out_dims[0] = in_dims[0];
+      out_dims[1] = in_dims[1] + pads[0] + pads[1];
+      out_dims[2] = in_dims[2] + pads[2] + pads[3];
+      out_dims[3] = in_dims[3];
+    }
+    T* out_data = out->mutable_data<T>(out_dims, context.GetPlace());
     const int pad_top = pads[0];
     const int pad_left = pads[2];
     const int num = in_dims[0];
@@ -356,7 +386,8 @@ template <typename T>
 class Pad2dGradCUDAKernel : public framework::OpKernel<T> {
  public:
   void Compute(const framework::ExecutionContext& context) const override {
-    auto pads = context.Attr<std::vector<int>>("paddings");
+    int pads[4];
+    GetPaddings(pads, context);
     auto mode = context.Attr<std::string>("mode");
     auto data_format = context.Attr<std::string>("data_format");
     auto* d_out = context.Input<Tensor>(framework::GradVarName("Out"));

python/paddle/fluid/layers/nn.py

@@ -6924,7 +6924,7 @@ def pad2d(input,
 
     Args:
         input (Variable): The input image with [N, C, H, W] format or [N, H, W, C] format.
-        paddings (tuple|list): The padding size. If padding is a tuple, it must
+        paddings (tuple|list|Variable): The padding size. If padding is a tuple, it must
             contain four integers, (padding_top, padding_bottom, padding_left, padding_right).
             Default: padding = [0, 0, 0, 0].
         mode (str): Three modes: constant(default), reflect, edge. Default: constant
@@ -6949,16 +6949,17 @@ def pad2d(input,
     helper = LayerHelper('pad2d', **locals())
     dtype = helper.input_dtype(input_param_name='input')
     out = helper.create_variable_for_type_inference(dtype)
+    inputs = {'X': input}
+    attrs = {'mode': mode, 'pad_value': pad_value, 'data_format': data_format}
+
+    if isinstance(paddings, Variable):
+        inputs['Paddings'] = paddings
+        attrs['paddings'] = []
+    else:
+        attrs['paddings'] = paddings
+
     helper.append_op(
-        type='pad2d',
-        inputs={'X': input},
-        outputs={"Out": out},
-        attrs={
-            'paddings': paddings,
-            'mode': mode,
-            'pad_value': pad_value,
-            'data_frmat': data_format
-        })
+        type='pad2d', inputs=inputs, outputs={"Out": out}, attrs=attrs)
 
     return out
 

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

@@ -636,13 +636,21 @@ class TestBook(unittest.TestCase):
         with program_guard(program):
             input = layers.data(
                 name="input", shape=[3, 100, 100], dtype="float32")
+            paddings = layers.fill_constant(shape=[4], dtype='int32', value=1)
             out = layers.pad2d(
                 input,
                 paddings=[1, 2, 3, 4],
                 mode='reflect',
                 data_format='NCHW',
                 name="shape")
+            out_1 = layers.pad2d(
+                input,
+                paddings=paddings,
+                mode='reflect',
+                data_format='NCHW',
+                name="shape")
             self.assertIsNotNone(out)
+            self.assertIsNotNone(out_1)
         print(str(program))
 
     def test_prelu(self):

python/paddle/fluid/tests/unittests/test_pad2d_op.py

@@ -20,11 +20,17 @@ from op_test import OpTest
 class TestPad2dOp(OpTest):
     def setUp(self):
         self.pad_value = 0.0
+        self.variable_paddings = False
         self.initTestCase()
         self.op_type = "pad2d"
         self.inputs = {'X': np.random.random(self.shape).astype("float32"), }
         self.attrs = {}
-        self.attrs['paddings'] = np.array(self.paddings).flatten()
+        if self.variable_paddings:
+            self.attrs['paddings'] = []
+            self.inputs['Paddings'] = np.array(self.paddings).flatten().astype(
+                "int32")
+        else:
+            self.attrs['paddings'] = np.array(self.paddings).flatten()
         self.attrs['pad_value'] = self.pad_value
         self.attrs['mode'] = self.mode
         self.attrs['data_format'] = self.data_format
@@ -98,5 +104,24 @@ class TestCase5(TestPad2dOp):
         self.data_format = "NHWC"
 
 
+class TestCase6(TestPad2dOp):
+    def initTestCase(self):
+        self.shape = (2, 4, 4, 2)
+        self.paddings = [0, 1, 2, 3]
+        self.mode = "constant"
+        self.pad_value = 1.2
+        self.data_format = "NHWC"
+        self.variable_paddings = True
+
+
+class TestCase7(TestPad2dOp):
+    def initTestCase(self):
+        self.shape = (2, 3, 4, 4)
+        self.paddings = [0, 1, 2, 3]
+        self.mode = "reflect"
+        self.data_format = "NCHW"
+        self.variable_paddings = True
+
+
 if __name__ == '__main__':
     unittest.main()