Compelete basic framework

paddle/pybind/protobuf.cc

@@ -240,13 +240,7 @@ void BindOpDesc(py::module &m) {
       .value("BLOCK", AttrType::BLOCK);
 
   py::class_<OpDescBind> op_desc(m, "OpDesc", "");
-  op_desc
-      .def("__init__",
-           [](OpDescBind &self, const std::string &type,
-              const VariableNameMap &inputs, const VariableNameMap &outputs,
-              const AttributeMap &attrs) {
-             new (&self) OpDescBind(type, inputs, outputs, attrs);
-           })
+  op_desc.def("__init__", [](OpDescBind &self) { new (&self) OpDescBind(); })
       .def("type", &OpDescBind::Type)
       .def("set_type", &OpDescBind::SetType)
       .def("input", &OpDescBind::Input)

paddle/pybind/pybind.cc

@@ -285,8 +285,8 @@ All parameter, weight, gradient are variables in Paddle.
   m.def("get_grad_op_desc",
         [](const OpDescBind &op_desc,
            const std::unordered_set<std::string> &no_grad_set,
-           std::unordered_map<std::string, std::string> &grad_to_var,
            const std::vector<BlockDescBind *> &grad_sub_block) {
+          std::unordered_map<std::string, std::string> grad_to_var;
           std::vector<std::unique_ptr<OpDescBind>> grad_op_descs =
               framework::OpInfoMap::Instance()
                   .Get(op_desc.Type())
@@ -297,7 +297,7 @@ All parameter, weight, gradient are variables in Paddle.
               grad_op_descs.begin(), grad_op_descs.end(),
               grad_op_desc_ptrs.begin(),
               [](std::unique_ptr<OpDescBind> &p) { return p.release(); });
-          return grad_op_desc_ptrs;
+          return std::make_pair(grad_op_desc_ptrs, grad_to_var);
         });
   m.def("prune", [](const ProgramDescBind &origin,
                     const std::vector<std::array<size_t, 2>> &targets) {

python/paddle/v2/fluid/backward.py

@@ -6,7 +6,8 @@ import pdb
 __all__ = ['append_backward_ops']
 
 
-def rename_arg(op_desc_list, old_name, new_name, begin_idx=None, end_idx=None):
+def _rename_arg_(op_desc_list, old_name, new_name, begin_idx=None,
+                 end_idx=None):
     if begin_idx is None:
         begin_idx = 0
     if end_idx is None:
@@ -16,6 +17,21 @@ def rename_arg(op_desc_list, old_name, new_name, begin_idx=None, end_idx=None):
         op_desc_list[i].rename_output(old_name, new_name)
 
 
+def _create_op_desc_(op_type, inputs, outputs, attrs):
+    op_desc = core.OpDesc()
+    op_desc.set_type(op_type)
+    for para, args in inputs.iteritems():
+        op_desc.set_input(para, args)
+    for para, args in outputs.iteritems():
+        op_desc.set_output(para, args)
+    for name, val in attrs.iteritems():
+        if isinstance(val, framework.Block):
+            op_desc.set_block_attr(name, val.desc)
+        else:
+            op_desc.set_attr(name, val)
+    return op_desc
+
+
 def backward_impl(target,
                   block,
                   target_block,
@@ -23,9 +39,9 @@ def backward_impl(target,
                   grad_info_map,
                   callback=None):
     grad_op_descs = []
-    grad_to_var = {}
+    grad_to_var = dict()
     program = block.program
-    for each_op in block.ops:
+    for each_op in reversed(block.ops):
         grad_sub_block_list = []
         if each_op.has_attr("sub_block"):
             sub_block_idx = each_op.block_attr("sub_block")
@@ -34,10 +50,10 @@ def backward_impl(target,
             backward_impl(target, sub_block, grad_sub_block, no_grad_set,
                           grad_info_map, callback)
             grad_sub_block_list.append(grad_sub_block)
-        grad_op_desc = core.get_grad_op_desc(each_op.desc,
-                                             no_grad_set[block.idx],
-                                             grad_to_var, grad_sub_block_list)
+        grad_op_desc, op_grad_to_var = core.get_grad_op_desc(
+            each_op.desc, no_grad_set[block.idx], grad_sub_block_list)
         grad_op_descs.append(grad_op_desc)
+        grad_to_var = dict(grad_to_var, **op_grad_to_var)
     # grad_op_descs = [[op1_g1, op1_g2], [op2_g], ...]
     # flatten grad_op_descs
     grad_op_descs = [op for sublist in grad_op_descs for op in sublist]  # ?????
@@ -48,11 +64,10 @@ def backward_impl(target,
     for pos, op_desc in enumerate(grad_op_descs):
         for var_name in op_desc.input_arg_names():
             if len(var_inputs[var_name]) > 1:
-                pdb.set_trace()
-                pending_sum_ops.append((core.OpDesc(
-                    type="sum_op",
+                pending_sum_ops.append((_create_op_desc_(
+                    op_type="sum_op",
                     inputs=var_inputs[var_name],
-                    output=[var_name],
+                    outputs=[var_name],
                     attrs={}), pos))
                 var_inputs[var_name] = [var_name]
         for var_name in op_desc.output_arg_names():
@@ -66,8 +81,8 @@ def backward_impl(target,
                     var_rename_count[var_name] = var_rename_count[var_name] + 1
                     # rename original var_name
                     var_inputs[var_name][0] = new_name
-                    rename_arg(grad_op_descs, var_name, new_name, 0, pos)
-                    rename_arg(pending_sum_ops, var_name, new_name)
+                    _rename_arg_(grad_op_descs, var_name, new_name, 0, pos)
+                    _rename_arg_(pending_sum_ops, var_name, new_name)
 
                 new_name = var_name + "@RENAME@" + \
                     str(var_rename_count[var_name])
@@ -76,10 +91,11 @@ def backward_impl(target,
                 var_inputs[var_name].append(new_name)
     for var_name, inputs in var_inputs.iteritems():
         if len(inputs) > 1:
-            pdb.set_trace()
-            pending_sum_ops.append((core.OpDesc("sum_op", {"X": inputs},
-                                                {"Out": var_name}, {}),
-                                    len(grad_op_descs)))
+            pending_sum_ops.append((_create_op_desc_(
+                op_type="sum_op",
+                inputs={"X": inputs},
+                outputs={"Out": var_name},
+                attrs={}), len(grad_op_descs)))
     # TODO: remove op in no grad set
 
     # 根据append的顺序可以看出pending_sum_ops一定是根据sum_op的插入位置排序的
@@ -103,15 +119,22 @@ def backward_impl(target,
         target_block.desc.var(grad_target_name)
         grad_op_descs.insert(
             0,
-            core.OpDesc(u"fill_constant", {}, {
-                u"Out": [unicode(grad_target_name, "ascii")]
-            }, {u"shape": (1),
-                u"value": 1.0,
-                u"dtype": core.DataType.FP32}))
+            _create_op_desc_(
+                op_type="fill_constant",
+                inputs={},
+                outputs={"Out": [grad_target_name]},
+                attrs={
+                    "shape": [1],
+                    "value": 1.0,
+                    "dtype": core.DataType.FP32
+                }))
     # insert backward operators to target_block
     for op_desc in grad_op_descs:
+        op_desc.infer_var_type(target_block.desc)
+        op_desc.infer_shape(target_block.desc)
         target_block.desc.append_allocated_op(op_desc)
 
+    pdb.set_trace()
     target_block.sync_with_cpp()
 
 
@@ -147,6 +170,7 @@ def append_backward_ops(loss, parameter_list=None, no_grad_set=None):
 
     grad_info_map = dict()
     root_block = loss.block.program.block(0)
+    pdb.set_trace()
     backward_impl(loss, root_block, root_block, no_grad_set, grad_info_map)
     pdb.set_trace()
     if parameter_list is not None:
@@ -159,7 +183,7 @@ def append_backward_ops(loss, parameter_list=None, no_grad_set=None):
         if param not in grad_info_map:
             raise ValueError("param %s is not in map" % param)
         grad_info = grad_info_map[param]
-        grad_block = loss.block.program.block(grad_info[1])
+        grad_block = grad_info[1]
         if not grad_block.has_var(grad_info[0]):
             raise ValueError("grad block[{0}] did not have grad var {1}".format(
                 grad_info[1], grad_info[0]))