ArmNN
 24.02
Reduce.cpp
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1 //
2 // Copyright © 2021 Arm Ltd and Contributors. All rights reserved.
3 // SPDX-License-Identifier: MIT
4 //
5 
6 #include "Reduce.hpp"
7 
9 
11 
12 #include <cstddef>
13 #include <functional>
14 #include <limits>
15 
16 namespace armnn
17 {
18 
19 bool NextIndex(const unsigned int numDims, const armnn::TensorShape& dims, std::vector<unsigned int>& current)
20 {
21  unsigned int carry = 1;
22 
23  for (unsigned int idx = numDims; idx-- > 0; )
24  {
25  unsigned int current_val = current[idx] + carry;
26  if (dims[idx] == current_val)
27  {
28  current[idx] = 0;
29  }
30  else
31  {
32  current[idx] = current_val;
33  carry = 0;
34  break;
35  }
36  }
37  return (carry == 0);
38 }
39 
40 unsigned int ReducedOutputOffset(const unsigned int numDims,
41  const armnn::TensorShape& dims,
42  std::vector<unsigned int>& index,
43  const unsigned int numAxis,
44  const std::vector<unsigned int>& axis)
45 {
46  unsigned int offset = 0;
47  for (unsigned int idx = 0; idx < numDims; ++idx)
48  {
49  bool isAxis = false;
50  if (!axis.empty())
51  {
52  for (unsigned int axisIdx = 0; axisIdx < numAxis; ++axisIdx)
53  {
54  if (idx == axis[axisIdx])
55  {
56  isAxis = true;
57  break;
58  }
59  }
60  }
61  if (!isAxis)
62  {
63  offset = offset * dims[idx] + index[idx];
64  }
65  }
66  return offset;
67 }
68 
69 
70 void Reduce(const TensorInfo& inputInfo,
71  const TensorInfo& outputInfo,
72  Decoder<float>& input,
73  Encoder<float>& output,
74  const std::vector<uint32_t> axis,
75  const ReduceOperation reduceOperation)
76 {
77  armnn::TensorShape inputDims = inputInfo.GetShape();
78  unsigned int inputNumDims = inputInfo.GetNumDimensions();
79  unsigned int numOutputs = outputInfo.GetNumElements();
80 
81  // Initialise temp output
82  std::vector<float> tempOut(numOutputs);
83  switch(reduceOperation)
84  {
87  std::fill(tempOut.begin(), tempOut.end(), 0.0f);
88  break;
90  std::fill(tempOut.begin(), tempOut.end(), 1.0f);
91  break;
93  std::fill(tempOut.begin(), tempOut.end(), -1 * std::numeric_limits<float>::max());
94  break;
96  std::fill(tempOut.begin(), tempOut.end(), std::numeric_limits<float>::max());
97  break;
98  default:
99  throw armnn::InvalidArgumentException("Unknown reduce method: " +
100  std::to_string(static_cast<int>(reduceOperation)));
101  }
102 
103  // Initialise temp index
104  std::vector<unsigned int> tempIndex(inputNumDims, 0);
105 
106  std::vector<unsigned int> resolvedAxis = axis;
107  if (resolvedAxis.empty())
108  {
109  for (unsigned int idx = 0; idx < inputNumDims; ++idx)
110  {
111  resolvedAxis.push_back(idx);
112  }
113  }
114  auto numResolvedAxis = armnn::numeric_cast<unsigned int>(resolvedAxis.size());
115 
116  // Iterates through input_data and operates over the reduced axis
117  for (bool hasNext = true; hasNext; hasNext = NextIndex(inputNumDims, inputDims, tempIndex))
118  {
119  unsigned int inputOffset = ReducedOutputOffset(inputNumDims, inputDims, tempIndex, 0, {});
120  unsigned int outputOffset = ReducedOutputOffset(inputNumDims, inputDims, tempIndex,
121  numResolvedAxis, resolvedAxis);
122  input[inputOffset];
123  auto inputValue = input.Get();
124  switch(reduceOperation)
125  {
128  tempOut[outputOffset] += inputValue;
129  break;
131  tempOut[outputOffset] *= inputValue;
132  break;
134  if (inputValue > tempOut[outputOffset])
135  {
136  tempOut[outputOffset] = inputValue;
137  }
138  break;
140  if (inputValue < tempOut[outputOffset])
141  {
142  tempOut[outputOffset] = inputValue;
143  }
144  break;
145  default:
146  throw armnn::InvalidArgumentException("Unknown reduce method: " +
147  std::to_string(static_cast<int>(reduceOperation)));
148  }
149  }
150 
151  // Takes average by num of elements added to get MEAN
152  size_t numElementsInAxis = 1;
153  for (unsigned int idx = 0; idx < numResolvedAxis; ++idx)
154  {
155  unsigned int current = inputDims[resolvedAxis[idx]];
156  ARMNN_ASSERT(armnn::numeric_cast<float>(current) <
157  (std::numeric_limits<float>::max() / armnn::numeric_cast<float>(numElementsInAxis)));
158  numElementsInAxis *= current;
159  }
160 
161  for (unsigned int idx = 0; idx < numOutputs; ++idx)
162  {
163  output[idx];
164  if (reduceOperation == ReduceOperation::Mean)
165  {
166  if (numElementsInAxis > 0)
167  {
168  output.Set(tempOut[idx] / armnn::numeric_cast<float>(numElementsInAxis));
169  }
170  }
171  else
172  {
173  output.Set(tempOut[idx]);
174  }
175  }
176 }
177 
178 } //namespace armnn
ARMNN_ASSERT
#define ARMNN_ASSERT(COND)
Definition: Assert.hpp:14
armnn::Decoder< float >
armnn::TensorInfo::GetNumElements
unsigned int GetNumElements() const
Definition: Tensor.hpp:198
armnn::Encoder::Set
virtual void Set(IType right)=0
WorkloadData.hpp
armnn::TensorInfo
Definition: Tensor.hpp:152
armnn::TensorInfo::GetNumDimensions
unsigned int GetNumDimensions() const
Definition: Tensor.hpp:197
armnn::Reduce
void Reduce(const TensorInfo &inputInfo, const TensorInfo &outputInfo, Decoder< float > &input, Encoder< float > &output, const std::vector< uint32_t > axis, const ReduceOperation reduceOperation)
Definition: Reduce.cpp:70
armnn::ReduceOperation::Mean
@ Mean
NumericCast.hpp
armnn::TensorShape
Definition: Tensor.hpp:20
armnn::Encoder< float >
armnn::InvalidArgumentException
Definition: Exceptions.hpp:80
armnn::ReducedOutputOffset
unsigned int ReducedOutputOffset(const unsigned int numDims, const armnn::TensorShape &dims, std::vector< unsigned int > &index, const unsigned int numAxis, const std::vector< unsigned int > &axis)
Definition: Reduce.cpp:40
armnn::ReduceOperation::Sum
@ Sum
armnn::Decoder::Get
virtual IType Get() const =0
armnn::ReduceOperation::Prod
@ Prod
armnn::TensorInfo::GetShape
const TensorShape & GetShape() const
Definition: Tensor.hpp:193
Reduce.hpp
armnn
Copyright (c) 2021 ARM Limited and Contributors.
Definition: 01_00_quick_start.dox:6
armnn::ReduceOperation
ReduceOperation
Definition: Types.hpp:157
armnn::ReduceOperation::Min
@ Min
armnn::ReduceOperation::Max
@ Max
armnn::NextIndex
bool NextIndex(const unsigned int numDims, const armnn::TensorShape &dims, std::vector< unsigned int > &current)
Definition: Reduce.cpp:19