1 /* Copyright 2015 The TensorFlow Authors. All Rights Reserved.
2 
3 Licensed under the Apache License, Version 2.0 (the "License");
4 you may not use this file except in compliance with the License.
5 You may obtain a copy of the License at
6 
7     http://www.apache.org/licenses/LICENSE-2.0
8 
9 Unless required by applicable law or agreed to in writing, software
10 distributed under the License is distributed on an "AS IS" BASIS,
11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 See the License for the specific language governing permissions and
13 limitations under the License.
14 ==============================================================================*/
15 
16 #ifndef TENSORFLOW_CORE_GRAPH_GRAPH_CONSTRUCTOR_H_
17 #define TENSORFLOW_CORE_GRAPH_GRAPH_CONSTRUCTOR_H_
18 
19 #include "tensorflow/core/framework/graph.pb.h"
20 #include "tensorflow/core/graph/graph.h"
21 #include "tensorflow/core/graph/tensor_id.h"
22 #include "tensorflow/core/lib/core/status.h"
23 
24 namespace tensorflow {
25 class ShapeRefiner;
26 
27 // Construct a Graph *g out of a GraphDef gdef. Returns non-OK on
28 // error, in which case *g is left in an incomplete state.
29 //
30 // *g is expected to be an empty graph (with no more than a source and sink
31 // nodes) when provided to ConvertGraphDefToGraph. To enhance an existing Graph,
32 // see ImportGraphDef.
33 struct GraphConstructorOptions {
GraphConstructorOptionsGraphConstructorOptions34   GraphConstructorOptions() {}
35 
36   // If true, allows internal ops in the GraphDef.
37   bool allow_internal_ops = false;
38 
39   // If true, the graph def is expected to have fully specified
40   // devices for all nodes. A node in the resulting graph "g" has the
41   // device name set accordingly.
42   //
43   // TODO(zhifengc): if possible, consider removing this option.
44   bool expect_device_spec = false;
45 };
46 extern Status ConvertGraphDefToGraph(const GraphConstructorOptions& opts,
47                                      const GraphDef& gdef, Graph* g);
48 
49 // Same as ConvertGraphDefToGraph, but takes just nodes.  Used by function
50 // instantiation.
51 // TODO(irving): This will turn into std::vector<NodeInfoPtr> soon.
52 extern Status ConvertNodeDefsToGraph(const GraphConstructorOptions& opts,
53                                      gtl::ArraySlice<NodeDef> nodes, Graph* g);
54 
55 // Options for calling ImportGraphDef().
56 struct ImportGraphDefOptions {
ImportGraphDefOptionsImportGraphDefOptions57   ImportGraphDefOptions()
58       : uniquify_names(false),
59         uniquify_prefix(false),
60         skip_mapped_nodes(false),
61         validate_shape(true) {}
62 
63   // Name prefix to use for nodes imported from the GraphDef.  For example, if
64   // prefix="animals" and GraphDef contains a node "bunny" then the node will be
65   // named "animals/bunny" in *g. Must not be already used as a node name or
66   // prefix in the graph.
67   string prefix;
68 
69   // If true, imported node names will be modified if their name already exists
70   // in the graph. If false, conflicting names will be treated as an error. Note
71   // that this option has no effect if `prefix` is specified, since `prefix`
72   // will guarantee all node names are unique.
73   bool uniquify_names;
74 
75   // If true, `prefix` will be modified if it already exists as a node name or
76   // prefix in the graph. If false, a conflicting prefix will be treated as an
77   // error. This option has no effect if `prefix` isn't specified.
78   bool uniquify_prefix;
79 
80   // Maps tensors in `gdef` to existing tensors in `g`. Inputs in `gdef`
81   // corresponding to `input_map` keys will be remapped to the nodes in `g`
82   // corresponding to the values.
83   //
84   // Keys should not include `prefix`, i.e., a key ID's name should be the name
85   // as it originally appears in `gdef`.
86   //
87   // If this is non-empty, ImportGraphDef must be called with the shape refiner
88   // used to create the existing nodes referenced in `input_map`.
89   // TODO(skyewm): can we remove this requirement? How do we access the original
90   // shape refiner?
91   std::map<SafeTensorId, SafeTensorId> input_map;
92 
93   // If true, nodes that will have all output edges removed because of
94   // overrides in `input_map` will not be imported.
95   bool skip_mapped_nodes;
96 
97   // The names of existing nodes in `g` that the imported graph should have
98   // control dependencies on.
99   //
100   // Note that to avoid creating many redundant control edges, ImportGraphDef()
101   // won't add control edges to nodes that will inherit the dependencies from
102   // other nodes in `gdef`.
103   std::vector<string> control_dependencies;
104 
105   // Tensors in `gdef` that will be returned via the ImportGraphDefResults
106   // output parameter of `ImportGraphDef()`. If this list is non-empty, the
107   // caller must pass a results object to `ImportGraphDef()`. The
108   // `return_tensors` field will be populated with the imported nodes in `g`.
109   //
110   // Entries should not include `prefix`, i.e., each ID's name should be the
111   // name as it originally appears in `gdef`.
112   //
113   // If this contains a tensor that's also being remapped via `input_map`, the
114   // corresponding existing tensor in `g` will be returned.
115   std::vector<SafeTensorId> return_tensors;
116 
117   // The names of nodes in `gdef` that will be returned via the
118   // ImportGraphDefResults output parameter of `ImportGraphDef()`. If this list
119   // is non-empty, the caller must pass a results object to
120   // `ImportGraphDef()`. The `return_nodes` field will be populated with the
121   // imported nodes in `g`.
122   //
123   // Entries should not include `prefix`, i.e., each node's name should be the
124   // name as it originally appears in `gdef`.
125   //
126   // Unlike `return_tensors`, `input_map` has no effect on the nodes
127   // returned. `return_nodes` must be empty if `skip_mapped_nodes` is true.
128   // TODO(skyewm): make this work with `skip_mapped_nodes` if there's a need.
129   std::vector<string> return_nodes;
130 
131   // If true, checks that all colocation constraints are nodes in the GraphDef.
132   bool validate_colocation_constraints = true;
133 
134   // If false skips shape validation.
135   bool validate_shape;
136 
137   // TODO(ashankar): Enable handling of GraphDefs produced by newer binaries
138   // with ops that are not defined in the binary calling ImportGraphDef.
139   // Similar to the producer_op_list argument to import_graph_def in the
140   // python API.
141 
142   // Try to set default execution device for this grapth.
143   string default_device;
144 };
145 
146 // Optional results that may be returned by ImportGraphDef.
147 struct ImportGraphDefResults {
148   // The requested tensors associated with
149   // ImportGraphDefOptions::return_tensors. Note that the index may be different
150   // than the requested index if the returned tensor has been remapped according
151   // to `input_map`.
152   typedef int Index;
153   std::vector<std::pair<Node*, Index>> return_tensors;
154 
155   // The requested nodes associated with ImportGraphDefOptions::return_nodes.
156   std::vector<Node*> return_nodes;
157 
158   // Keys in ImportGraphDefOptions::input_map that don't appear in `gdef` and
159   // weren't used as an input to any node in `gdef`. These keys are likely due
160   // to typos, and callers may wish to treat their existence as an error.
161   std::vector<SafeTensorId> missing_unused_input_map_keys;
162 };
163 
164 // Adds the graph in GraphDef `gdef` into an existing Graph `*g`.
165 //
166 // On error, returns non-OK and leaves `*g` unmodified.
167 //
168 // `refiner` can be null. It should be non-null if the caller
169 // intends to add additional nodes to the graph after the import. This
170 // allows the caller to validate shapes of those nodes (since
171 // ShapeRefiner::AddNode must be called in topological order).
172 //
173 // `results` must be non-null if `opts.return_tensors` or `opts.result_nodes` is
174 // non-empty. It can also be set to fetch the unused input map keys. If it's
175 // non-null, all the vector fields must be empty.
176 //
177 // TODO(ashankar): Push this mechanism and get rid of Session::Extend()
178 // as a means of enhancing an existing Graph.
179 extern Status ImportGraphDef(const ImportGraphDefOptions& opts,
180                              const GraphDef& gdef, Graph* g,
181                              ShapeRefiner* refiner,
182                              ImportGraphDefResults* results = nullptr);
183 
184 // Make a copy of "src" into "*dest".
185 //
186 // REQUIRES: "*dest" is a freshly allocated graph without any nodes or edges
187 // other than the implicit Source/Sink nodes.
188 extern void CopyGraph(const Graph& src, Graph* dest);
189 
190 }  // namespace tensorflow
191 
192 #endif  // TENSORFLOW_CORE_GRAPH_GRAPH_CONSTRUCTOR_H_
193