1 | /* Copyright 2022 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 | #ifndef TENSORFLOW_CORE_KERNELS_DATA_OPTIONAL_OPS_UTIL_H_ |
16 | #define TENSORFLOW_CORE_KERNELS_DATA_OPTIONAL_OPS_UTIL_H_ |
17 | |
18 | #include <functional> |
19 | #include <memory> |
20 | #include <utility> |
21 | #include <vector> |
22 | |
23 | #include "tensorflow/core/framework/tensor.h" |
24 | #include "tensorflow/core/framework/variant_tensor_data.h" |
25 | #include "tensorflow/core/util/tensor_ops_util.h" |
26 | |
27 | namespace tensorflow { |
28 | namespace data { |
29 | |
30 | const char kOptionalVariantTypeName[] = "tensorflow::data::Optional" ; |
31 | |
32 | // An `OptionalVariant` can represent either an "actual value" (a tuple of |
33 | // tensors) or "none", and may be stored in a DT_VARIANT tensor. |
34 | class OptionalVariant { |
35 | public: |
36 | // Create an `OptionalVariant` with no actual value. |
37 | OptionalVariant() : values_(nullptr) {} |
38 | |
39 | // Create an `OptionalVariant` with the actual value given by the tuple of |
40 | // tensors in `values`. |
41 | explicit OptionalVariant(std::vector<Tensor> values) { |
42 | values_ = std::make_shared<std::vector<Tensor>>(std::move(values)); |
43 | } |
44 | |
45 | OptionalVariant(const OptionalVariant& other) : values_(other.values_) {} |
46 | |
47 | // Returns true if `this` represents an actual value. |
48 | bool has_value() const { return values_ != nullptr; } |
49 | |
50 | // REQUIRES: `this->has_value()` must be true. |
51 | const std::vector<Tensor>& get_values() const { |
52 | DCHECK(values_) << "Tried to get values from an empty OptionalVariant" ; |
53 | return *values_; |
54 | } |
55 | |
56 | // Implementations of the necessary methods for using `OptionalVariant` |
57 | // objects in DT_VARIANT tensors. |
58 | string TypeName() const { return kOptionalVariantTypeName; } |
59 | void Encode(VariantTensorData* data) const { |
60 | data->set_metadata(values_ != nullptr); |
61 | if (values_ != nullptr) { |
62 | for (const auto& t : *values_) { |
63 | *(data->add_tensors()) = t; |
64 | } |
65 | } |
66 | } |
67 | |
68 | bool Decode(const VariantTensorData& data) { |
69 | if (data.type_name() != TypeName()) { |
70 | return false; |
71 | } |
72 | bool has_value = false; |
73 | if (!data.get_metadata(&has_value)) { |
74 | return false; |
75 | } |
76 | if (has_value) { |
77 | values_ = std::make_shared<std::vector<Tensor>>(data.tensors()); |
78 | } else { |
79 | values_.reset(); |
80 | } |
81 | return true; |
82 | } |
83 | |
84 | string DebugString() const { |
85 | if (values_) { |
86 | return strings::StrCat("OptionalVariant<" , "values: (" , |
87 | absl::StrJoin(*values_, ", " , |
88 | [](string* s, const Tensor& elem) { |
89 | *s = elem.DebugString(); |
90 | }), |
91 | ")>" ); |
92 | } else { |
93 | return strings::StrCat("OptionalVariant<None>" ); |
94 | } |
95 | } |
96 | |
97 | private: |
98 | std::shared_ptr<const std::vector<Tensor>> values_; |
99 | }; |
100 | |
101 | Status OptionalZerosLike(OpKernelContext* ctx, const OptionalVariant& x, |
102 | OptionalVariant* y, |
103 | std::function<Status(OpKernelContext* ctx, |
104 | const Tensor& input, Tensor* out)> |
105 | zeros_like_func); |
106 | |
107 | Status OptionalBinaryAdd( |
108 | OpKernelContext* ctx, const OptionalVariant& a, const OptionalVariant& b, |
109 | OptionalVariant* out, |
110 | std::function<Status(OpKernelContext* ctx, const Tensor& a, const Tensor& b, |
111 | Tensor* out)> |
112 | binary_add_func); |
113 | |
114 | } // namespace data |
115 | } // namespace tensorflow |
116 | |
117 | #endif // TENSORFLOW_CORE_KERNELS_DATA_OPTIONAL_OPS_UTIL_H_ |
118 | |