1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "Operations"
18 
19 #include <algorithm>
20 #include <cmath>
21 #include <vector>
22 
23 #include "HalInterfaces.h"
24 #include "IndexedShapeWrapper.h"
25 #include "OperationResolver.h"
26 #include "OperationsUtils.h"
27 #include "Tracing.h"
28 
29 namespace android {
30 namespace nn {
31 namespace elu {
32 
33 using namespace hal;
34 
35 constexpr uint32_t kNumInputs = 2;
36 constexpr uint32_t kInputTensor = 0;
37 constexpr uint32_t kAlphaScalar = 1;
38 
39 constexpr uint32_t kNumOutputs = 1;
40 constexpr uint32_t kOutputTensor = 0;
41 
42 namespace {
43 
44 template <typename T>
eluFloat(const T * inputData,const Shape & inputShape,const T alpha,T * outputData,const Shape & outputShape)45 bool eluFloat(const T* inputData, const Shape& inputShape, const T alpha, T* outputData,
46               const Shape& outputShape) {
47     NNTRACE_COMP("ELU");
48     int numElements = getNumberOfElements(inputShape);
49     for (int i = 0; i < numElements; ++i) {
50         float x = static_cast<float>(inputData[i]);
51         outputData[i] = static_cast<T>(std::max(0.f, x) + std::min(0.f, alpha * (std::exp(x) - 1)));
52     }
53     return true;
54 }
55 
56 }  // namespace
57 
validate(const IOperationValidationContext * context)58 bool validate(const IOperationValidationContext* context) {
59     NN_RET_CHECK_EQ(context->getNumInputs(), kNumInputs);
60     NN_RET_CHECK_EQ(context->getNumOutputs(), kNumOutputs);
61     auto inputType = context->getInputType(kInputTensor);
62     if (inputType == OperandType::TENSOR_FLOAT16 || inputType == OperandType::TENSOR_FLOAT32) {
63         NN_RET_CHECK(validateHalVersion(context, HalVersion::V1_3));
64     } else {
65         NN_RET_CHECK_FAIL() << "Unsupported tensor type for operation ELU";
66     }
67     auto scalarType =
68             inputType == OperandType::TENSOR_FLOAT16 ? OperandType::FLOAT16 : OperandType::FLOAT32;
69     return validateInputTypes(context, {inputType, scalarType}) &&
70            validateOutputTypes(context, {inputType});
71 }
72 
prepare(IOperationExecutionContext * context)73 bool prepare(IOperationExecutionContext* context) {
74     Shape inputShape = context->getInputShape(kInputTensor);
75     return context->setOutputShape(kOutputTensor, inputShape);
76 }
77 
execute(IOperationExecutionContext * context)78 bool execute(IOperationExecutionContext* context) {
79     // Bypass execution in the case of zero-sized input.
80     if (getNumberOfElements(context->getOutputShape(kOutputTensor)) == 0) return true;
81     switch (context->getInputType(kInputTensor)) {
82         case OperandType::TENSOR_FLOAT16:
83             return eluFloat(context->getInputBuffer<_Float16>(kInputTensor),
84                             context->getInputShape(kInputTensor),
85                             context->getInputValue<_Float16>(kAlphaScalar),
86                             context->getOutputBuffer<_Float16>(kOutputTensor),
87                             context->getOutputShape(kOutputTensor));
88         case OperandType::TENSOR_FLOAT32:
89             return eluFloat(context->getInputBuffer<float>(kInputTensor),
90                             context->getInputShape(kInputTensor),
91                             context->getInputValue<float>(kAlphaScalar),
92                             context->getOutputBuffer<float>(kOutputTensor),
93                             context->getOutputShape(kOutputTensor));
94         default:
95             NN_RET_CHECK_FAIL() << "Unsupported tensor type for operation ELU";
96     }
97 }
98 
99 }  // namespace elu
100 
101 NN_REGISTER_OPERATION(ELU, "ELU", elu::validate, elu::prepare, elu::execute);
102 
103 }  // namespace nn
104 }  // namespace android
105