Merge branch 'develop' of https://github.com/PaddlePaddle/Paddle into feature/fast_executor

CMakeLists.txt

@@ -204,12 +204,11 @@ include(external/snappy)    # download snappy
 include(external/snappystream)
 include(external/threadpool)
 
+set(WITH_ANAKIN OFF CACHE STRING "Disable Anakin first, will add it later." FORCE)
 if(WITH_GPU)
     include(cuda)
     include(tensorrt)
     include(external/anakin)
-else()
-  set(WITH_ANAKIN OFF CACHE STRING "Anakin is valid only when GPU is set." FORCE)
 endif()
 
 include(cudnn)              # set cudnn libraries, must before configure

paddle/fluid/API.spec

@@ -6,7 +6,7 @@ paddle.fluid.Program.create_block ArgSpec(args=['self', 'parent_idx'], varargs=N
 paddle.fluid.Program.current_block ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Program.get_desc ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Program.global_block ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
-paddle.fluid.Program.inference_optimize ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.Program.inference_optimize ArgSpec(args=['self', 'export_for_deployment'], varargs=None, keywords=None, defaults=(True,))
 paddle.fluid.Program.list_vars ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Program.optimized_guard ArgSpec(args=[], varargs='args', keywords='kwds', defaults=None)
 paddle.fluid.Program.parse_from_string ArgSpec(args=['binary_str'], varargs=None, keywords=None, defaults=None)
@@ -18,6 +18,9 @@ paddle.fluid.Operator.all_attrs ArgSpec(args=['self'], varargs=None, keywords=No
 paddle.fluid.Operator.attr ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Operator.attr_type ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Operator.block_attr ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.Operator.block_attr_id ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.Operator.blocks_attr ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.Operator.blocks_attr_ids ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Operator.has_attr ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Operator.has_kernel ArgSpec(args=['self', 'op_type'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.Operator.input ArgSpec(args=['self', 'name'], varargs=None, keywords=None, defaults=None)
@@ -52,7 +55,7 @@ paddle.fluid.Inferencer.__init__ ArgSpec(args=['self', 'infer_func', 'param_path
 paddle.fluid.Inferencer.infer ArgSpec(args=['self', 'inputs', 'return_numpy'], varargs=None, keywords=None, defaults=(True,))
 paddle.fluid.DistributeTranspiler.__init__ ArgSpec(args=['self', 'config'], varargs=None, keywords=None, defaults=(None,))
 paddle.fluid.DistributeTranspiler.get_pserver_program ArgSpec(args=['self', 'endpoint'], varargs=None, keywords=None, defaults=None)
-paddle.fluid.DistributeTranspiler.get_startup_program ArgSpec(args=['self', 'endpoint', 'pserver_program'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.DistributeTranspiler.get_startup_program ArgSpec(args=['self', 'endpoint', 'pserver_program', 'startup_program'], varargs=None, keywords=None, defaults=(None,))
 paddle.fluid.DistributeTranspiler.get_trainer_program ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.DistributeTranspiler.transpile ArgSpec(args=['self', 'trainer_id', 'program', 'pservers', 'trainers', 'sync_mode'], varargs=None, keywords=None, defaults=(None, '127.0.0.1:6174', 1, True))
 paddle.fluid.InferenceTranspiler.__init__ 
@@ -74,7 +77,7 @@ paddle.fluid.io.save_persistables ArgSpec(args=['executor', 'dirname', 'main_pro
 paddle.fluid.io.load_vars ArgSpec(args=['executor', 'dirname', 'main_program', 'vars', 'predicate', 'filename'], varargs=None, keywords=None, defaults=(None, None, None, None))
 paddle.fluid.io.load_params ArgSpec(args=['executor', 'dirname', 'main_program', 'filename'], varargs=None, keywords=None, defaults=(None, None))
 paddle.fluid.io.load_persistables ArgSpec(args=['executor', 'dirname', 'main_program', 'filename'], varargs=None, keywords=None, defaults=(None, None))
-paddle.fluid.io.save_inference_model ArgSpec(args=['dirname', 'feeded_var_names', 'target_vars', 'executor', 'main_program', 'model_filename', 'params_filename'], varargs=None, keywords=None, defaults=(None, None, None))
+paddle.fluid.io.save_inference_model ArgSpec(args=['dirname', 'feeded_var_names', 'target_vars', 'executor', 'main_program', 'model_filename', 'params_filename', 'export_for_deployment'], varargs=None, keywords=None, defaults=(None, None, None, True))
 paddle.fluid.io.load_inference_model ArgSpec(args=['dirname', 'executor', 'model_filename', 'params_filename'], varargs=None, keywords=None, defaults=(None, None))
 paddle.fluid.io.get_inference_program ArgSpec(args=['target_vars', 'main_program'], varargs=None, keywords=None, defaults=(None,))
 paddle.fluid.initializer.ConstantInitializer.__init__ ArgSpec(args=['self', 'value', 'force_cpu'], varargs=None, keywords=None, defaults=(0.0, False))
@@ -156,6 +159,7 @@ paddle.fluid.layers.relu ArgSpec(args=['x'], varargs=None, keywords=None, defaul
 paddle.fluid.layers.log ArgSpec(args=['x'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.layers.crop ArgSpec(args=['x', 'shape', 'offsets', 'name'], varargs=None, keywords=None, defaults=(None, None, None))
 paddle.fluid.layers.rank_loss ArgSpec(args=['label', 'left', 'right', 'name'], varargs=None, keywords=None, defaults=(None,))
+paddle.fluid.layers.flatten ArgSpec(args=['x', 'axis', 'name'], varargs=None, keywords=None, defaults=(1, None))
 paddle.fluid.layers.data ArgSpec(args=['name', 'shape', 'append_batch_size', 'dtype', 'lod_level', 'type', 'stop_gradient'], varargs=None, keywords=None, defaults=(True, 'float32', 0, VarType.LOD_TENSOR, True))
 paddle.fluid.layers.open_recordio_file ArgSpec(args=['filename', 'shapes', 'lod_levels', 'dtypes', 'pass_num', 'for_parallel'], varargs=None, keywords=None, defaults=(1, True))
 paddle.fluid.layers.open_files ArgSpec(args=['filenames', 'shapes', 'lod_levels', 'dtypes', 'thread_num', 'buffer_size', 'pass_num', 'is_test'], varargs=None, keywords=None, defaults=(None, None, 1, None))
@@ -324,7 +328,7 @@ paddle.fluid.contrib.BeamSearchDecoder.update_array ArgSpec(args=['self', 'array
 paddle.fluid.contrib.memory_usage ArgSpec(args=['program', 'batch_size'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.transpiler.DistributeTranspiler.__init__ ArgSpec(args=['self', 'config'], varargs=None, keywords=None, defaults=(None,))
 paddle.fluid.transpiler.DistributeTranspiler.get_pserver_program ArgSpec(args=['self', 'endpoint'], varargs=None, keywords=None, defaults=None)
-paddle.fluid.transpiler.DistributeTranspiler.get_startup_program ArgSpec(args=['self', 'endpoint', 'pserver_program'], varargs=None, keywords=None, defaults=None)
+paddle.fluid.transpiler.DistributeTranspiler.get_startup_program ArgSpec(args=['self', 'endpoint', 'pserver_program', 'startup_program'], varargs=None, keywords=None, defaults=(None,))
 paddle.fluid.transpiler.DistributeTranspiler.get_trainer_program ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None)
 paddle.fluid.transpiler.DistributeTranspiler.transpile ArgSpec(args=['self', 'trainer_id', 'program', 'pservers', 'trainers', 'sync_mode'], varargs=None, keywords=None, defaults=(None, '127.0.0.1:6174', 1, True))
 paddle.fluid.transpiler.InferenceTranspiler.__init__ 

paddle/fluid/framework/ir/graph.h

@@ -28,6 +28,38 @@ namespace paddle {
 namespace framework {
 namespace ir {
 
+/*
+ * The graph is a Directed Acyclic Single Static Assignment Graph.
+ *
+ * In more detail, the following properties must hold:
+ *
+ *   The graph shouldn't contain cycle. Each node is a black-box to the graph
+ *   so the node itself could be a loop operator.
+ *
+ *   Each Variable-type node has only one input (thus single static assignment).
+ *
+ *   The output/input of operator is variable and the output/input of variable
+ *   is operator.
+ *
+ * The following data harzards in Program are addressed in the Graph:
+ *
+ *   Write-After-Read
+ *     a = op1(x)
+ *     x = op2(b)
+ *     A control-dependency connection is created bettwen op1 and op2 such that
+ *     op1->op2, so as to ensure correct order.
+ *
+ *   Write-After-Write
+ *     x = op1(a)
+ *     x = op2(b)
+ *     A control-dependency connection is created between op1 and op2 such that
+ *     op1->op2, so as to ensure correct order.
+ *
+ * Other properties currently hold, but is not enforced yet:
+ *
+ *   Variable-type node (not control dep) with the same variable name share
+ *   the same underlying VarDesc.
+ */
 class Graph {
  public:
   explicit Graph(const ProgramDesc &program);

paddle/fluid/framework/ir/graph_test.cc

@@ -36,7 +36,7 @@ class SumOpMaker : public OpProtoAndCheckerMaker {
  public:
   void Make() {
     AddInput("X", "").AsDuplicable();
-    AddOutput("Out", "");
+    AddOutput("Out", "").AsDuplicable();
     AddComment("");
   }
 };
@@ -59,11 +59,27 @@ class SumOpVarTypeInference : public VarTypeInference {
     block->Var(out_var_name)->SetType(default_var_type);
   }
 };
+
+class DummyOpMaker : public OpProtoAndCheckerMaker {
+ public:
+  void Make() {
+    AddInput("X", "").AsDuplicable();
+    AddOutput("Out", "").AsDuplicable();
+    AddComment("");
+  }
+};
+
+class DummyOpVarTypeInference : public VarTypeInference {
+ public:
+  void operator()(const OpDesc &op_desc, BlockDesc *block) const override {}
+};
 }  // namespace framework
 }  // namespace paddle
 
 REGISTER_OPERATOR(sum, paddle::framework::NOP, paddle::framework::SumOpMaker,
                   paddle::framework::SumOpVarTypeInference);
+REGISTER_OPERATOR(dummy, paddle::framework::NOP, paddle::framework::SumOpMaker,
+                  paddle::framework::SumOpVarTypeInference);
 REGISTER_OPERATOR(sum_without_infer_var_type, paddle::framework::NOP,
                   paddle::framework::SumOpMaker);
 
@@ -110,5 +126,83 @@ TEST(GraphTest, Basic) {
   }
   ASSERT_EQ(nodes.size(), 5);
 }
+
+TEST(GraphTest, WriteAfterRead) {
+  // void Test() {
+  ProgramDesc prog;
+  auto *op = prog.MutableBlock(0)->AppendOp();
+  op->SetType("sum");
+  op->SetInput("X", {"a"});
+  op->SetOutput("Out", {"b"});
+  op->SetAttr("op_role", 1);
+
+  op = prog.MutableBlock(0)->AppendOp();
+  op->SetType("dummy");
+  op->SetInput("X", {"c"});
+  op->SetOutput("Out", {"a"});
+  op->SetAttr("op_role", 1);
+
+  prog.MutableBlock(0)->Var("a")->SetType(proto::VarType::LOD_TENSOR);
+  prog.MutableBlock(0)->Var("b")->SetType(proto::VarType::LOD_TENSOR);
+  prog.MutableBlock(0)->Var("c")->SetType(proto::VarType::LOD_TENSOR);
+
+  std::unique_ptr<ir::Graph> g(new ir::Graph(prog));
+  ir::Node *control_dep1 = nullptr;
+  ir::Node *control_dep2 = nullptr;
+  for (ir::Node *n : g->Nodes()) {
+    if (n->Name() == "sum") {
+      ASSERT_EQ(n->outputs[0]->Name(), "b");
+      ASSERT_TRUE(ir::IsControlDepVar(*n->outputs[1]));
+      control_dep1 = n->outputs[1];
+      ASSERT_EQ(n->outputs.size(), 2);
+    }
+    if (n->Name() == "dummy") {
+      ASSERT_EQ(n->inputs[0]->Name(), "c");
+      ASSERT_TRUE(ir::IsControlDepVar(*n->inputs[1]));
+      control_dep2 = n->inputs[1];
+      ASSERT_EQ(n->inputs.size(), 2);
+    }
+  }
+  ASSERT_EQ(control_dep1, control_dep2);
+}
+
+TEST(GraphTest, WriteAfterWrite) {
+  // void Test() {
+  ProgramDesc prog;
+  auto *op = prog.MutableBlock(0)->AppendOp();
+  op->SetType("sum");
+  op->SetInput("X", {"a"});
+  op->SetOutput("Out", {"b"});
+  op->SetAttr("op_role", 1);
+
+  op = prog.MutableBlock(0)->AppendOp();
+  op->SetType("dummy");
+  op->SetInput("X", {"c"});
+  op->SetOutput("Out", {"b"});
+  op->SetAttr("op_role", 1);
+
+  prog.MutableBlock(0)->Var("a")->SetType(proto::VarType::LOD_TENSOR);
+  prog.MutableBlock(0)->Var("b")->SetType(proto::VarType::LOD_TENSOR);
+  prog.MutableBlock(0)->Var("c")->SetType(proto::VarType::LOD_TENSOR);
+
+  std::unique_ptr<ir::Graph> g(new ir::Graph(prog));
+  ir::Node *control_dep1 = nullptr;
+  ir::Node *control_dep2 = nullptr;
+  for (ir::Node *n : g->Nodes()) {
+    if (n->Name() == "sum") {
+      ASSERT_EQ(n->outputs[0]->Name(), "b");
+      ASSERT_TRUE(ir::IsControlDepVar(*n->outputs[1]));
+      ASSERT_EQ(n->outputs.size(), 2);
+      control_dep1 = n->outputs[1];
+    }
+    if (n->Name() == "dummy") {
+      ASSERT_EQ(n->inputs[0]->Name(), "c");
+      ASSERT_TRUE(ir::IsControlDepVar(*n->inputs[1]));
+      control_dep2 = n->inputs[1];
+      ASSERT_EQ(n->inputs.size(), 2);
+      ASSERT_EQ(control_dep1, control_dep2);
+    }
+  }
+}
 }  // namespace framework
 }  // namespace paddle

paddle/fluid/framework/op_desc.cc

@@ -238,7 +238,20 @@ Attribute OpDesc::GetNullableAttr(const std::string &name) const {
   }
 }
 
-int OpDesc::GetBlockAttr(const std::string &name) const {
+std::vector<int> OpDesc::GetBlocksAttrIds(const std::string &name) const {
+  auto it = attrs_.find(name);
+  PADDLE_ENFORCE(it != attrs_.end(), "Attribute %s is not found", name);
+  auto blocks = boost::get<std::vector<BlockDesc *>>(it->second);
+
+  std::vector<int> ids;
+  for (auto n : blocks) {
+    ids.push_back(n->ID());
+  }
+
+  return ids;
+}
+
+int OpDesc::GetBlockAttrId(const std::string &name) const {
   auto it = attrs_.find(name);
   PADDLE_ENFORCE(it != attrs_.end(), "Attribute %s is not found", name);
   return boost::get<BlockDesc *>(it->second)->ID();

paddle/fluid/framework/op_desc.h

@@ -83,7 +83,9 @@ class OpDesc {
 
   Attribute GetNullableAttr(const std::string &name) const;
 
-  int GetBlockAttr(const std::string &name) const;
+  int GetBlockAttrId(const std::string &name) const;
+
+  std::vector<int> GetBlocksAttrIds(const std::string &name) const;
 
   void Rename(const std::string &old_name, const std::string &new_name);
 

paddle/fluid/framework/program_desc.cc

@@ -58,7 +58,7 @@ ProgramDesc::ProgramDesc(const ProgramDesc &o) {
       for (const std::string &attr_name : op->AttrNames()) {
         if (op->GetAttrType(attr_name) == proto::AttrType::BLOCK) {
           int sub_block_id =
-              o.Block(block_id).Op(op_id)->GetBlockAttr(attr_name);
+              o.Block(block_id).Op(op_id)->GetBlockAttrId(attr_name);
           op->SetBlockAttr(attr_name, MutableBlock(sub_block_id));
         }
       }

paddle/fluid/framework/tensor.cc

@@ -112,5 +112,6 @@ Tensor& Tensor::Resize(const DDim& dims) {
 const DDim& Tensor::dims() const { return dims_; }
 
 int64_t Tensor::numel() const { return product(dims_); }
+
 }  // namespace framework
 }  // namespace paddle

paddle/fluid/framework/tensor_impl.h

@@ -59,6 +59,14 @@ inline T* Tensor::mutable_data(platform::Place place) {
 }
 
 inline Tensor ReshapeToMatrix(const Tensor& src, int num_col_dims) {
+  int rank = src.dims().size();
+  PADDLE_ENFORCE_GE(
+      rank, 2,
+      "'ReshapeToMatrix()' is only used for flatten high rank "
+      "tensors to matrixs. Can not be used in reshaping vectors.");
+  if (rank == 2) {
+    return src;
+  }
   Tensor res;
   res.ShareDataWith(src);
   res.Resize(flatten_to_2d(src.dims(), num_col_dims));

paddle/fluid/inference/api/api_impl.cc

@@ -22,6 +22,9 @@ limitations under the License. */
 #include <vector>
 
 #include "paddle/fluid/inference/api/api_impl.h"
+#include "paddle/fluid/platform/profiler.h"
+
+DEFINE_bool(profile, false, "Turn on profiler for fluid");
 
 namespace paddle {
 namespace {
@@ -58,6 +61,15 @@ bool NativePaddlePredictor::Init(
     std::shared_ptr<framework::Scope> parent_scope) {
   VLOG(3) << "Predictor::init()";
 
+  if (FLAGS_profile) {
+    LOG(WARNING) << "Profiler is actived, might affect the performance";
+    LOG(INFO) << "You can turn off by set gflags '-profile false'";
+
+    auto tracking_device = config_.use_gpu ? platform::ProfilerState::kAll
+                                           : platform::ProfilerState::kCPU;
+    platform::EnableProfiler(tracking_device);
+  }
+
   if (config_.use_gpu) {
     place_ = paddle::platform::CUDAPlace(config_.device);
   } else {
@@ -102,6 +114,10 @@ bool NativePaddlePredictor::Init(
 }
 
 NativePaddlePredictor::~NativePaddlePredictor() {
+  if (FLAGS_profile) {
+    platform::DisableProfiler(platform::EventSortingKey::kTotal,
+                              "./profile.log");
+  }
   if (sub_scope_) {
     scope_->DeleteScope(sub_scope_);
   }

paddle/fluid/operators/cross_entropy_op.cc

@@ -28,23 +28,26 @@ class CrossEntropyOp : public framework::OperatorWithKernel {
 
     auto x_dims = ctx->GetInputDim("X");
     auto label_dims = ctx->GetInputDim("Label");
-    PADDLE_ENFORCE_EQ(x_dims.size(), 2UL, "Input(X)'s rank should be 2.");
+    int rank = x_dims.size();
-    PADDLE_ENFORCE_EQ(label_dims.size(), 2UL,
+    PADDLE_ENFORCE_EQ(rank, label_dims.size(),
-                      "Input(Label)'s rank should be 2.");
+                      "Input(X) and Input(Label) shall have the same rank.");
-    PADDLE_ENFORCE_EQ(x_dims[0], label_dims[0],
+    PADDLE_ENFORCE_EQ(framework::slice_ddim(x_dims, 0, rank - 1),
-                      "The 1st dimension of Input(X) and Input(Label) should "
+                      framework::slice_ddim(label_dims, 0, rank - 1),
-                      "be equal.");
+                      "Input(X) and Input(Label) shall have the same shape "
+                      "except the last dimension.");
     if (ctx->Attrs().Get<bool>("soft_label")) {
-      PADDLE_ENFORCE_EQ(x_dims[1], label_dims[1],
+      PADDLE_ENFORCE_EQ(x_dims[rank - 1], label_dims[rank - 1],
-                        "If Attr(soft_label) == true, the 2nd dimension of "
+                        "If Attr(soft_label) == true, the last dimension of "
                         "Input(X) and Input(Label) should be equal.");
     } else {
-      PADDLE_ENFORCE_EQ(label_dims[1], 1UL,
+      PADDLE_ENFORCE_EQ(label_dims[rank - 1], 1UL,
-                        "If Attr(softLabel) == false, the 2nd dimension of "
+                        "If Attr(softLabel) == false, the last dimension of "
                         "Input(Label) should be 1.");
     }
 
-    ctx->SetOutputDim("Y", {x_dims[0], 1});
+    auto y_dims = x_dims;
+    y_dims[rank - 1] = 1;
+    ctx->SetOutputDim("Y", y_dims);
     ctx->ShareLoD("X", /*->*/ "Y");
   }
 
@@ -74,24 +77,28 @@ class CrossEntropyGradientOp : public framework::OperatorWithKernel {
     auto x_dims = ctx->GetInputDim("X");
     auto label_dims = ctx->GetInputDim("Label");
     auto dy_dims = ctx->GetInputDim(framework::GradVarName("Y"));
-    PADDLE_ENFORCE_EQ(x_dims.size(), 2, "Input(X)'s rank should be 2.");
+    int rank = x_dims.size();
-    PADDLE_ENFORCE_EQ(dy_dims.size(), 2, "Input(Y@Grad)'s rank should be 2.");
+    PADDLE_ENFORCE_EQ(dy_dims.size(), rank,
-    PADDLE_ENFORCE_EQ(label_dims.size(), 2, "Input(Label)'s rank should be 2.");
+                      "Input(Y@Grad) and Input(X) should have the same rank.");
-    PADDLE_ENFORCE_EQ(x_dims[0], label_dims[0],
+    PADDLE_ENFORCE_EQ(label_dims.size(), rank,
-                      "The 1st dimension of Input(X) and Input(Label) should "
+                      "Input(Label) and Input(X) should have the same rank.");
-                      "be equal.");
+    PADDLE_ENFORCE_EQ(framework::slice_ddim(x_dims, 0, rank - 1),
-    PADDLE_ENFORCE_EQ(x_dims[0], dy_dims[0],
+                      framework::slice_ddim(label_dims, 0, rank - 1),
-                      "The 1st dimension of Input(X) and Input(Y@Grad) should "
+                      "The Input(X) and Input(Label) should have the same "
-                      "be equal.");
+                      "shape except the last dimension.");
-    PADDLE_ENFORCE_EQ(dy_dims[1], 1,
+    PADDLE_ENFORCE_EQ(framework::slice_ddim(x_dims, 0, rank - 1),
-                      "The 2nd dimension of Input(Y@Grad) should be 1.");
+                      framework::slice_ddim(dy_dims, 0, rank - 1),
+                      "The Input(X) and Input(Y@Grad) should have the same "
+                      "shape except the last dimension.");
+    PADDLE_ENFORCE_EQ(dy_dims[rank - 1], 1,
+                      "The last dimension of Input(Y@Grad) should be 1.");
     if (ctx->Attrs().Get<bool>("soft_label")) {
-      PADDLE_ENFORCE_EQ(x_dims[1], label_dims[1],
+      PADDLE_ENFORCE_EQ(x_dims[rank - 1], label_dims[rank - 1],
-                        "When Attr(soft_label) == true, the 2nd dimension of "
+                        "When Attr(soft_label) == true, the last dimension of "
                         "Input(X) and Input(Label) should be equal.");
     } else {
-      PADDLE_ENFORCE_EQ(label_dims[1], 1,
+      PADDLE_ENFORCE_EQ(label_dims[rank - 1], 1,
-                        "When Attr(soft_label) == false, the 2nd dimension of "
+                        "When Attr(soft_label) == false, the last dimension of "
                         "Input(Label) should be 1.");
     }
     ctx->SetOutputDim(framework::GradVarName("X"), x_dims);
@@ -113,18 +120,20 @@ class CrossEntropyOpMaker : public framework::OpProtoAndCheckerMaker {
  public:
   void Make() override {
     AddInput("X",
-             "(Tensor, default Tensor<float>), a 2-D tensor with shape [N x D],"
+             "(Tensor, default Tensor<float>), a tensor whose last dimension "
-             " where N is the batch size and D is the number of classes. "
+             "size is equal to the number of classes. This input is a "
-             "This input is a probability computed by the previous operator, "
+             "probability computed by the previous operator, which is almost "
-             "which is almost always the result of a softmax operator.");
+             "always the result of a softmax operator.");
-    AddInput("Label",
+    AddInput(
-             "(Tensor), the ground truth which is a 2-D tensor. When "
+        "Label",
-             "soft_label is set to false, Label is a Tensor<int64> with shape "
+        "(Tensor), the tensor which represents the ground truth. It has the "
-             "[N x 1]. When soft_label is set to true, Label is a "
+        "same shape with 'X' except the last dimension. When soft_label is set "
-             "Tensor<float/double> with shape [N x D].");
+        "to false, the last dimension size is 1; when soft_label is set to "
+        "true, the last dimension size is equal to the number of classes.");
     AddOutput("Y",
-              "(Tensor, default Tensor<float>), a 2-D tensor with shape "
+              "(Tensor, default Tensor<float>), a tensor whose shape is same "
-              "[N x 1]. The cross entropy loss.");
+              "with 'X' except that the last dimension size is 1. It "
+              "represents the cross entropy loss.");
     AddAttr<bool>("soft_label",
                   "(bool, default false), a flag indicating whether to "
                   "interpretate the given labels as soft labels.")
@@ -132,6 +141,12 @@ class CrossEntropyOpMaker : public framework::OpProtoAndCheckerMaker {
     AddComment(R"DOC(
 CrossEntropy Operator.
 
+The input 'X' and 'Label' will first be logically flattened to 2-D matrixs. 
+The matrix's second dimension(row length) is as same as the original last 
+dimension, and the first dimension(column length) is the product of all other 
+original dimensions. Then the softmax computation will take palce on each raw 
+of flattened matrixs.
+
 It supports both standard cross-entropy and soft-label cross-entropy loss
 computation.
 1) One-hot cross-entropy:

paddle/fluid/operators/cross_entropy_op.h

@@ -33,8 +33,13 @@ class CrossEntropyOpKernel : public framework::OpKernel<T> {
     auto* y = ctx.Output<Tensor>("Y");
     y->mutable_data<T>(ctx.GetPlace());
 
+    int rank = x->dims().size();
+    Tensor x_2d = framework::ReshapeToMatrix(*x, rank - 1);
+    Tensor labels_2d = framework::ReshapeToMatrix(*labels, rank - 1);
+    Tensor y_2d = framework::ReshapeToMatrix(*y, rank - 1);
+
     math::CrossEntropyFunctor<DeviceContext, T>()(
-        ctx.template device_context<DeviceContext>(), y, x, labels,
+        ctx.template device_context<DeviceContext>(), &y_2d, &x_2d, &labels_2d,
         ctx.Attr<bool>("soft_label"));
   }
 };
@@ -98,9 +103,12 @@ class CrossEntropyGradientOpKernel : public framework::OpKernel<T> {
     auto* dy = ctx.Input<Tensor>(framework::GradVarName("Y"));
     auto* label = ctx.Input<Tensor>("Label");
     auto* dx = ctx.Output<Tensor>(framework::GradVarName("X"));
-    auto* dx_data = dx->mutable_data<T>(ctx.GetPlace());
+    T* dx_data = dx->mutable_data<T>(ctx.GetPlace());
 
-    int64_t class_num = x->dims()[1];
+    // Following computation only depends on the last dimension size. So it's
+    // unnecessary to convert tensors to 2-D views.
+    int rank = x->dims().size();
+    int64_t class_num = x->dims()[rank - 1];
     if (ctx.Attr<bool>("soft_label")) {
       XeSoftlabelGradFunctor<T> functor(dx_data, dy->data<T>(), x->data<T>(),
                                         label->data<T>(),

paddle/fluid/operators/shape_op.cc

@@ -38,7 +38,7 @@ class ShapeOpMaker : public framework::OpProtoAndCheckerMaker {
     AddInput("Input", "(Tensor), The input tensor.");
     AddOutput("Out",
               "(Tensor), The shape of input tensor, the data type of the shape"
-              " is int64_t, will be on the same device with the input Tensor.");
+              " is int32_t, will be on the same device with the input Tensor.");
     AddComment(R"DOC(
 Shape Operator
 
@@ -53,5 +53,5 @@ Get the shape of input tensor. Only support CPU input Tensor now.
 namespace ops = paddle::operators;
 REGISTER_OPERATOR(shape, ops::ShapeOp, ops::ShapeOpMaker,
                   paddle::framework::EmptyGradOpMaker);
-REGISTER_OP_CPU_KERNEL(shape, ops::ShapeKernel<int>, ops::ShapeKernel<int64_t>,
+REGISTER_OP_CPU_KERNEL(shape, ops::ShapeKernel<int>, ops::ShapeKernel<int32_t>,
                        ops::ShapeKernel<float>, ops::ShapeKernel<double>);

paddle/fluid/operators/shape_op.cu

@@ -15,6 +15,6 @@ limitations under the License. */
 #include "paddle/fluid/operators/shape_op.h"
 
 REGISTER_OP_CUDA_KERNEL(shape, paddle::operators::ShapeKernel<int>,
-                        paddle::operators::ShapeKernel<int64_t>,
+                        paddle::operators::ShapeKernel<int32_t>,
                         paddle::operators::ShapeKernel<float>,
                         paddle::operators::ShapeKernel<double>);

paddle/fluid/operators/shape_op.h

@@ -27,7 +27,7 @@ class ShapeKernel : public framework::OpKernel<T> {
   void Compute(const framework::ExecutionContext& ctx) const override {
     auto* in_t = ctx.Input<Tensor>("Input");
     auto* out_t = ctx.Output<Tensor>("Out");
-    auto out_data = out_t->mutable_data<int64_t>(platform::CPUPlace());
+    auto out_data = out_t->mutable_data<int32_t>(platform::CPUPlace());
     auto in_dims = in_t->dims();
     for (int i = 0; i < in_dims.size(); ++i) {
       out_data[i] = in_dims[i];

paddle/fluid/operators/softmax_op.h

@@ -31,16 +31,12 @@ class SoftmaxKernel : public framework::OpKernel<T> {
     // allocate memory on device.
     Out->mutable_data<T>(context.GetPlace());
 
-    auto dims = X->dims();
+    int rank = X->dims().size();
-    auto flattened_dims = framework::flatten_to_2d(dims, dims.size() - 1);
+    Tensor X_2d = framework::ReshapeToMatrix(*X, rank - 1);
-    framework::LoDTensor flattened_x;
+    Tensor Out_2d = framework::ReshapeToMatrix(*Out, rank - 1);
-    framework::LoDTensor flattened_out;
-    flattened_x.ShareDataWith(*X).Resize(flattened_dims);
-    flattened_out.ShareDataWith(*Out).Resize(flattened_dims);
 
     math::SoftmaxFunctor<DeviceContext, T>()(
-        context.template device_context<DeviceContext>(), &flattened_x,
+        context.template device_context<DeviceContext>(), &X_2d, &Out_2d);
-        &flattened_out);
   }
 };
 
@@ -55,18 +51,14 @@ class SoftmaxGradKernel : public framework::OpKernel<T> {
     // allocate memory on device.
     dX->mutable_data<T>(context.GetPlace());
 
-    auto dims = Out->dims();
+    int rank = Out->dims().size();
-    auto flattened_dims = framework::flatten_to_2d(dims, dims.size() - 1);
+    Tensor Out_2d = framework::ReshapeToMatrix(*Out, rank - 1);
-    framework::LoDTensor flattened_out;
+    Tensor dOut_2d = framework::ReshapeToMatrix(*dOut, rank - 1);
-    framework::LoDTensor flattened_d_out;
+    Tensor dX_2d = framework::ReshapeToMatrix(*dX, rank - 1);
-    framework::LoDTensor flattened_d_x;
-    flattened_out.ShareDataWith(*Out).Resize(flattened_dims);
-    flattened_d_out.ShareDataWith(*dOut).Resize(flattened_dims);
-    flattened_d_x.ShareDataWith(*dX).Resize(flattened_dims);
 
     math::SoftmaxGradFunctor<DeviceContext, T>()(
-        context.template device_context<DeviceContext>(), &flattened_out,
+        context.template device_context<DeviceContext>(), &Out_2d, &dOut_2d,
-        &flattened_d_out, &flattened_d_x);
+        &dX_2d);
   }
 };
 

paddle/fluid/platform/profiler.cc

@@ -270,12 +270,13 @@ struct EventItem {
   double min_time;
   double max_time;
   double ave_time;
+  float ratio;
 };
 
 // Print results
 void PrintProfiler(const std::vector<std::vector<EventItem>>& events_table,
                    const std::string& sorted_domain, const size_t name_width,
-                   const size_t data_width) {
+                   const size_t data_width, double total) {
   // Output header information
   std::cout << "\n------------------------->"
             << "     Profiling Report     "
@@ -300,7 +301,8 @@ void PrintProfiler(const std::vector<std::vector<EventItem>>& events_table,
   std::cout << std::setw(name_width) << "Event" << std::setw(data_width)
             << "Calls" << std::setw(data_width) << "Total"
             << std::setw(data_width) << "Min." << std::setw(data_width)
-            << "Max." << std::setw(data_width) << "Ave." << std::endl;
+            << "Max." << std::setw(data_width) << "Ave."
+            << std::setw(data_width) << "Ratio." << std::endl;
   for (size_t i = 0; i < events_table.size(); ++i) {
     for (size_t j = 0; j < events_table[i].size(); ++j) {
       const EventItem& event_item = events_table[i][j];
@@ -309,7 +311,9 @@ void PrintProfiler(const std::vector<std::vector<EventItem>>& events_table,
                 << std::setw(data_width) << event_item.total_time
                 << std::setw(data_width) << event_item.min_time
                 << std::setw(data_width) << event_item.max_time
-                << std::setw(data_width) << event_item.ave_time << std::endl;
+                << std::setw(data_width) << event_item.ave_time
+                << std::setw(data_width) << event_item.total_time / total
+                << std::endl;
     }
   }
   std::cout << std::endl;
@@ -359,6 +363,7 @@ void ParseEvents(const std::vector<std::vector<Event>>& events,
 
   std::vector<std::vector<EventItem>> events_table;
   size_t max_name_width = 0;
+  double total = 0.;  // the total time
   for (size_t i = 0; i < events.size(); i++) {
     std::list<Event> pushed_events;
     std::vector<EventItem> event_items;
@@ -379,6 +384,7 @@ void ParseEvents(const std::vector<std::vector<Event>>& events,
                                g_state == ProfilerState::kAll)
                                   ? rit->CudaElapsedMs(events[i][j])
                                   : rit->CpuElapsedMs(events[i][j]);
+          total += event_time;
 
           std::string event_name =
               "thread" + std::to_string(rit->thread_id()) + "::" + rit->name();
@@ -387,7 +393,8 @@ void ParseEvents(const std::vector<std::vector<Event>>& events,
           if (event_idx.find(event_name) == event_idx.end()) {
             event_idx[event_name] = event_items.size();
             EventItem event_item = {event_name, 1,          event_time,
-                                    event_time, event_time, event_time};
+                                    event_time, event_time, event_time,
+                                    0.};
             event_items.push_back(event_item);
           } else {
             int index = event_idx[event_name];
@@ -431,7 +438,7 @@ void ParseEvents(const std::vector<std::vector<Event>>& events,
   }
 
   // Print report
-  PrintProfiler(events_table, sorted_domain, max_name_width + 4, 12);
+  PrintProfiler(events_table, sorted_domain, max_name_width + 4, 12, total);
 }
 
 void DisableProfiler(EventSortingKey sorted_key,

paddle/fluid/pybind/protobuf.cc

@@ -301,7 +301,8 @@ void BindOpDesc(pybind11::module *m) {
              std::string ser(seriralized);
              self.SetAttr(name, ser);
            })
-      .def("block_attr", &pd::OpDesc::GetBlockAttr)
+      .def("block_attr_id", &pd::OpDesc::GetBlockAttrId)
+      .def("blocks_attr_ids", &pd::OpDesc::GetBlocksAttrIds)
       .def("check_attrs", &pd::OpDesc::CheckAttrs)
       .def("infer_shape", &pd::OpDesc::InferShape)
       .def("infer_var_type", &pd::OpDesc::InferVarType)

python/paddle/fluid/backward.py

@@ -344,7 +344,7 @@ def _append_backward_ops_(block,
         grad_sub_block_list = []
         # If the op has its own sub-block, deal with the sub-block first
         if op.has_attr("sub_block"):
-            sub_block = program.block(op.block_attr("sub_block"))
+            sub_block = program.block(op.block_attr_id("sub_block"))
             grad_sub_block = program.create_block()
             grad_sub_block._set_forward_block_idx(sub_block.idx)
             cb = _callback_lookup_(op)
@@ -406,7 +406,7 @@ def _append_backward_vars_(block, start_op_idx, grad_to_var, grad_info_map):
     for op_idx in range(start_op_idx, block.desc.op_size()):
         op_desc = block.desc.op(op_idx)
         if op_desc.has_attr("sub_block"):
-            sub_block = block.program.block(op_desc.block_attr("sub_block"))
+            sub_block = block.program.block(op_desc.block_attr_id("sub_block"))
             _append_backward_vars_(sub_block, 0, grad_to_var, grad_info_map)
         new_vars = set()
         # create new gradient variables

python/paddle/fluid/framework.py

@@ -476,23 +476,25 @@ class Operator(object):
                  attrs=None):
         self.block = block
         self.desc = desc
-        self.attrs = attrs
+        # note: not add self.attrs here:
-        if self.attrs is None:
+        # https://github.com/PaddlePaddle/Paddle/pull/12583#pullrequestreview-145093173
-            self.attrs = dict()
+        op_attrs = attrs
+        if op_attrs is None:
+            op_attrs = dict()
         del attrs
 
         op_maker = core.op_proto_and_checker_maker
 
-        if op_maker.kOpRoleAttrName() not in self.attrs:
+        if op_maker.kOpRoleAttrName() not in op_attrs:
-            self.attrs[op_maker.kOpRoleAttrName()] = self.block.program.op_role
+            op_attrs[op_maker.kOpRoleAttrName()] = self.block.program.op_role
 
         role_var_name = op_maker.kOpRoleVarAttrName()
         if len(self.block.program.
-               op_role_var) != 0 and role_var_name not in self.attrs:
+               op_role_var) != 0 and role_var_name not in op_attrs:
-            self.attrs[role_var_name] = self.block.program.op_role_var
+            op_attrs[role_var_name] = self.block.program.op_role_var
 
-        if role_var_name in self.attrs and len(self.attrs[role_var_name]) == 0:
+        if role_var_name in op_attrs and len(op_attrs[role_var_name]) == 0:
-            del self.attrs[role_var_name]
+            del op_attrs[role_var_name]
 
         if len(self.desc.type()) != 0:
             return
@@ -576,15 +578,14 @@ class Operator(object):
                     arg.op = self
                 self.desc.set_output(out_proto.name, out_arg_names)
 
-        if self.attrs is not None:
+        if op_attrs is not None:
-            if not isinstance(self.attrs, dict):
+            if not isinstance(op_attrs, dict):
                 raise TypeError("'attrs' should be a dict.")
             for attr in proto.attrs:
                 attr_name = attr.name
-                if (attr_name not in self.attrs) or (
+                if (attr_name not in op_attrs) or (op_attrs[attr_name] is None):
-                        self.attrs[attr_name] is None):
                     continue
-                attr_val = self.attrs[attr_name]
+                attr_val = op_attrs[attr_name]
                 self._update_desc_attr(attr_name, attr_val)
 
         self.desc.check_attrs()
@@ -732,7 +733,6 @@ class Operator(object):
         Raises:
             ValueError: If the type of value doesn't match with desc.attr_type(name).
         """
-        self.attrs[name] = val
         self._update_desc_attr(name, val)
 
     def _update_desc_attr(self, name, val):
@@ -774,9 +774,9 @@ class Operator(object):
         """
         return self.desc.attr(name)
 
-    def block_attr(self, name):
+    def block_attr_id(self, name):
         """
-        Get the block attribute by name.
+        Get the block attribute's id by name.
 
         Args:
             name(str): the attribute name.
@@ -784,22 +784,74 @@ class Operator(object):
         Returns:
             int: the block index.
         """
-        return self.desc.block_attr(name)
+        return self.desc.block_attr_id(name)
+
+    def block_attr(self, name):
+        """
+        Get the block attribute  by name.
+
+        Args:
+            name(str): the attribute name.
+
+        Returns:
+            block: the block attribute.
+        """
+
+        id = self.block_attr_id(name)
+        assert (id >= 0 and id < len(self.block.program.blocks))
+        return self.block.program.blocks[id]
+
+    def blocks_attr(self, name):
+        """
+        Get the blocks attribute  by name.
+
+        Args:
+            name(str): the attribute name.
+
+        Returns:
+            list: list of the blocks attribute.
+        """
+        attrs = []
+        for i in self.blocks_attr_ids(name):
+            assert (i >= 0 and i < len(self.block.program.blocks))
+            attrs.append(self.block.program.blocks[i])
+
+        return attrs
+
+    def blocks_attr_ids(self, name):
+        """
+        Get the blocks attribute's ids by name.
+
+        Args:
+            name(str): the attribute name.
+
+        Returns:
+            list: list of the blocks ids.
+        """
+
+        return self.desc.blocks_attr_ids(name)
 
     def all_attrs(self):
         """
         Get the attribute dict.
 
         Returns:
-            dict: The Operator's attribute dict.
+            dict: The Operator's attribute dict, name->attr.
         """
         attr_names = self.attr_names
         attr_map = {}
         for n in attr_names:
-            if n == 'sub_block':
+            attr_type = self.desc.attr_type(n)
+            if attr_type == core.AttrType.BLOCK:
                 attr_map[n] = self.block_attr(n)
-            else:
+                continue
-                attr_map[n] = self.attr(n)
+
+            if attr_type == core.AttrType.BLOCKS:
+                attr_map[n] = self.blocks_attr(n)
+                continue
+
+            attr_map[n] = self.attr(n)
+
         return attr_map
 
 
@@ -1518,11 +1570,17 @@ class Program(object):
             The two code snippets above will generate same programs.
         """
         if for_test:
-            p = self.inference_optimize()
+            p = self.inference_optimize(export_for_deployment=False)
         else:
             p = Program()
+            p.current_block_idx = self.current_block_idx
+            p._seed = self._seed
             p.desc = core.ProgramDesc(self.desc)
-            p.blocks = [Block(p, i) for i in range(self.desc.num_blocks())]
+            p.blocks = [Block(p, i) for i in xrange(self.desc.num_blocks())]
+
+            p._current_role = self._current_role
+            p._op_role_var = self._op_role_var
+
             p._sync_with_cpp()
 
         p._copy_param_info_from(self)
@@ -1578,7 +1636,7 @@ class Program(object):
         res._sync_with_cpp()
         return res
 
-    def inference_optimize(self):
+    def inference_optimize(self, export_for_deployment=True):
         """
         This method will create a new program and do following adjustments on it:
         1. Remove all reader variables and their creator ops if exist.
@@ -1589,6 +1647,10 @@ class Program(object):
         attribute of operators to :code:`True`. All the :code:`Parameter`
         information will be lost.
 
+        Args:
+            export_for_deployment(bool): remove the read ops that are added by py_reader
+                                        for cpp inference library
+
         Notes: This API is a very low level API. Use
         :code:`Program.clone(for_test=True)` instead.
 
@@ -1603,16 +1665,17 @@ class Program(object):
         # remove all readers and the read_op if exist
         read_op_idx = 0
         root_block = res.desc.block(0)
-        while True:
+        if export_for_deployment:
-            if read_op_idx >= root_block.op_size() or root_block.op(
+            while True:
-                    read_op_idx).type() == 'read':
+                if read_op_idx >= root_block.op_size() or root_block.op(
-                break
+                        read_op_idx).type() == 'read':
-            read_op_idx += 1
+                    break
-        if read_op_idx < root_block.op_size():
+                read_op_idx += 1
-            root_block._remove_op(0, read_op_idx + 1)
+            if read_op_idx < root_block.op_size():
-        for var in root_block.all_vars():
+                root_block._remove_op(0, read_op_idx + 1)
-            if var.type() == core.VarDesc.VarType.READER:
+            for var in root_block.all_vars():
-                root_block._remove_var(var.name())
+                if var.type() == core.VarDesc.VarType.READER:
+                    root_block._remove_var(var.name())
 
         # change all `is_test` attributes to True
         for i in range(res.desc.num_blocks()):

python/paddle/fluid/initializer.py

@@ -264,7 +264,8 @@ class NormalInitializer(Initializer):
                 "dtype": int(var.dtype),
                 "mean": self._mean,
                 "std": self._std_dev,
-                "seed": self._seed
+                "seed": self._seed,
+                "use_mkldnn": False
             })
         var.op = op
         return op

python/paddle/fluid/io.py

@@ -555,7 +555,8 @@ def save_inference_model(dirname,
                          executor,
                          main_program=None,
                          model_filename=None,
-                         params_filename=None):
+                         params_filename=None,
+                         export_for_deployment=True):
     """
     Prune the given `main_program` to build a new program especially for inference,
     and then save it and all related parameters to given `dirname` by the `executor`.
@@ -577,6 +578,8 @@ def save_inference_model(dirname,
         params_filename(str|None): The name of file to save all related parameters.
                                    If it is setted None, parameters will be saved
                                    in separate files .
+        export_for_deployment(bool): remove the read ops that are added by py_reader
+                                    for cpp inference lib. Default True
 
     Returns:
         None
@@ -643,7 +646,8 @@ def save_inference_model(dirname,
     copy_program.desc.flush()
 
     pruned_program = copy_program.prune(targets=target_vars)
-    inference_program = pruned_program.inference_optimize()
+    inference_program = pruned_program.inference_optimize(
+        export_for_deployment=export_for_deployment)
     fetch_var_names = [v.name for v in target_vars]
 
     prepend_feed_ops(inference_program, feeded_var_names)

python/paddle/fluid/layers/detection.py

@@ -20,7 +20,9 @@ from .layer_function_generator import autodoc, templatedoc
 from ..layer_helper import LayerHelper
 from . import tensor
 from . import nn
+from . import ops
 import math
+import numpy
 from functools import reduce
 
 __all__ = [
@@ -264,10 +266,11 @@ def detection_output(loc,
         prior_box_var=prior_box_var,
         target_box=loc,
         code_type='decode_center_size')
-    old_shape = scores.shape
+    compile_shape = scores.shape
-    scores = nn.reshape(x=scores, shape=(-1, old_shape[-1]))
+    run_shape = ops.shape(scores)
+    scores = nn.flatten(x=scores, axis=2)
     scores = nn.softmax(input=scores)
-    scores = nn.reshape(x=scores, shape=old_shape)
+    scores = nn.reshape(x=scores, shape=compile_shape, actual_shape=run_shape)
     scores = nn.transpose(scores, perm=[0, 2, 1])
     scores.stop_gradient = True
     nmsed_outs = helper.create_tmp_variable(dtype=decoded_box.dtype)
@@ -677,9 +680,10 @@ def ssd_loss(location,
         raise ValueError("Only support mining_type == max_negative now.")
 
     num, num_prior, num_class = confidence.shape
+    conf_shape = ops.shape(confidence)
 
     def __reshape_to_2d(var):
-        return nn.reshape(x=var, shape=[-1, var.shape[-1]])
+        return nn.flatten(x=var, axis=2)
 
     # 1. Find matched boundding box by prior box.
     #   1.1 Compute IOU similarity between ground-truth boxes and prior boxes.
@@ -690,7 +694,8 @@ def ssd_loss(location,
 
     # 2. Compute confidence for mining hard examples
     # 2.1. Get the target label based on matched indices
-    gt_label = nn.reshape(x=gt_label, shape=gt_label.shape + (1, ))
+    gt_label = nn.reshape(
+        x=gt_label, shape=(len(gt_label.shape) - 1) * (0, ) + (-1, 1))
     gt_label.stop_gradient = True
     target_label, _ = target_assign(
         gt_label, matched_indices, mismatch_value=background_label)
@@ -701,9 +706,12 @@ def ssd_loss(location,
     target_label = __reshape_to_2d(target_label)
     target_label.stop_gradient = True
     conf_loss = nn.softmax_with_cross_entropy(confidence, target_label)
-
     # 3. Mining hard examples
-    conf_loss = nn.reshape(x=conf_loss, shape=(num, num_prior))
+    conf_loss = nn.reshape(
+        x=conf_loss,
+        shape=(num, num_prior),
+        actual_shape=ops.slice(
+            conf_shape, axes=[0], starts=[0], ends=[2]))
     conf_loss.stop_gradient = True
     neg_indices = helper.create_tmp_variable(dtype='int32')
     dtype = matched_indices.dtype
@@ -772,7 +780,11 @@ def ssd_loss(location,
     # 5.3 Compute overall weighted loss.
     loss = conf_loss_weight * conf_loss + loc_loss_weight * loc_loss
     # reshape to [N, Np], N is the batch size and Np is the prior box number.
-    loss = nn.reshape(x=loss, shape=[-1, num_prior])
+    loss = nn.reshape(
+        x=loss,
+        shape=(num, num_prior),
+        actual_shape=ops.slice(
+            conf_shape, axes=[0], starts=[0], ends=[2]))
     loss = nn.reduce_sum(loss, dim=1, keep_dim=True)
     if normalize:
         normalizer = nn.reduce_sum(target_loc_weight)
@@ -1005,13 +1017,7 @@ def multi_box_head(inputs,
     """
 
     def _reshape_with_axis_(input, axis=1):
-        if not (axis > 0 and axis < len(input.shape)):
+        out = nn.flatten(x=input, axis=axis)
-            raise ValueError("The axis should be smaller than "
-                             "the arity of input and bigger than 0.")
-        new_shape = [
-            -1, reduce(lambda x, y: x * y, input.shape[axis:len(input.shape)])
-        ]
-        out = nn.reshape(x=input, shape=new_shape)
         return out
 
     def _is_list_or_tuple_(data):
@@ -1101,11 +1107,13 @@ def multi_box_head(inputs,
             stride=stride)
 
         mbox_loc = nn.transpose(mbox_loc, perm=[0, 2, 3, 1])
-        new_shape = [
+        compile_shape = [
             mbox_loc.shape[0],
             mbox_loc.shape[1] * mbox_loc.shape[2] * mbox_loc.shape[3] / 4, 4
         ]
-        mbox_loc_flatten = nn.reshape(mbox_loc, shape=new_shape)
+        run_shape = tensor.assign(numpy.array([0, -1, 4]).astype("int32"))
+        mbox_loc_flatten = nn.reshape(
+            mbox_loc, shape=compile_shape, actual_shape=run_shape)
         mbox_locs.append(mbox_loc_flatten)
 
         # get conf
@@ -1117,11 +1125,15 @@ def multi_box_head(inputs,
             padding=pad,
             stride=stride)
         conf_loc = nn.transpose(conf_loc, perm=[0, 2, 3, 1])
-        new_shape = [
+        new_shape = [0, -1, num_classes]
+        compile_shape = [
             conf_loc.shape[0], conf_loc.shape[1] * conf_loc.shape[2] *
             conf_loc.shape[3] / num_classes, num_classes
         ]
-        conf_loc_flatten = nn.reshape(conf_loc, shape=new_shape)
+        run_shape = tensor.assign(
+            numpy.array([0, -1, num_classes]).astype("int32"))
+        conf_loc_flatten = nn.reshape(
+            conf_loc, shape=compile_shape, actual_shape=run_shape)
         mbox_confs.append(conf_loc_flatten)
 
     if len(box_results) == 1:

python/paddle/fluid/layers/nn.py

@@ -112,6 +112,7 @@ __all__ = [
     'log',
     'crop',
     'rank_loss',
+    'flatten',
 ]
 
 
@@ -5361,3 +5362,70 @@ def rank_loss(label, left, right, name=None):
                 "Right": right},
         outputs={'Out': out})
     return out
+
+
+def flatten(x, axis=1, name=None):
+    """
+    **Flatten layer**
+    Flattens the input tensor into a 2D matrix.
+
+    Examples:
+    Case 1:
+      Given
+        X.shape = (3, 100, 100, 4)
+      and
+        axis = 2
+      We get:
+        Out.shape = (3 * 100, 4 * 100)
+    
+    Case 2:
+      Given
+        X.shape = (3, 100, 100, 4)
+      and
+        axis = 0
+      We get:
+        Out.shape = (1, 3 * 100 * 100 * 4)
+
+    Args:
+        x (Variable): A tensor of rank >= axis.
+        axis (int): Indicate up to which input dimensions (exclusive) should 
+                    be flattened to the outer dimension of the output. 
+                    The value for axis must be in the range [0, R], where R
+                    is the rank of the input tensor. When axis = 0, the shape
+                    of the output tensor is (1, (d_0 X d_1 ... d_n), where the
+                    shape of the input tensor is (d_0, d_1, ... d_n).
+        name(str|None): A name for this layer(optional). If set None, the layer
+                        will be named automatically.
+
+    Returns:
+        Variable: A 2D tensor with the contents of the input tensor, with input
+                  dimensions up to axis flattened to the outer dimension of
+                  the output and remaining input dimensions flattened into the
+                  inner dimension of the output.
+
+    Raises:
+        ValueError: If x is not a variable.
+        ValueError: If axis is not in range [0, rank(x)]. 
+
+    Examples:
+
+        .. code-block:: python
+
+            x = fluid.layers.data(name="x", shape=[4, 4, 3], dtype="float32")
+            out = fluid.layers.flatten(x=x, axis=2)
+    """
+    helper = LayerHelper('flatten', **locals())
+
+    if not (isinstance(x, Variable)):
+        raise ValueError("The input x should be a Variable")
+
+    if not (isinstance(axis, int)) or axis > len(x.shape) or axis < 0:
+        raise ValueError("The axis should be a int, and in range [0, rank(x)]")
+
+    out = helper.create_tmp_variable(x.dtype)
+    helper.append_op(
+        type='flatten',
+        inputs={"X": x},
+        outputs={'Out': out},
+        attrs={"axis": axis})
+    return out