xref: /aosp_15_r20/external/armnn/src/armnn/TypesUtils.cpp (revision 89c4ff92f2867872bb9e2354d150bf0c8c502810)
1 //
2 // Copyright © 2017 Arm Ltd. All rights reserved.
3 // SPDX-License-Identifier: MIT
4 //
5 #include <armnn/TypesUtils.hpp>
6 #include <armnn/utility/Assert.hpp>
7 #include <armnn/utility/NumericCast.hpp>
8 
9 namespace
10 {
11 /// Workaround for std:isnan() not being implemented correctly for integral types in MSVC.
12 /// https://stackoverflow.com/a/56356405
13 /// @{
14 template <typename T, typename std::enable_if<std::is_integral<T>::value, T>::type* = nullptr>
IsNan(T x)15 inline int IsNan(T x)
16 {
17     // The spec defines integral types to be handled as if they were casted to doubles.
18     return std::isnan(static_cast<double>(x));
19 }
20 
21 template <typename T, typename std::enable_if<!std::is_integral<T>::value, T>::type * = nullptr>
IsNan(T x)22 inline int IsNan(T x)
23 {
24     return std::isnan(x);
25 }
26 /// @}
27 }    // namespace std
28 
29 template<typename QuantizedType>
Quantize(float value,float scale,int32_t offset)30 QuantizedType armnn::Quantize(float value, float scale, int32_t offset)
31 {
32     static_assert(IsQuantizedType<QuantizedType>(), "Not an integer type.");
33     constexpr QuantizedType max = std::numeric_limits<QuantizedType>::max();
34     constexpr QuantizedType min = std::numeric_limits<QuantizedType>::lowest();
35     ARMNN_ASSERT(scale != 0.f);
36     ARMNN_ASSERT(!std::isnan(value));
37 
38     float clampedValue = std::min(std::max((static_cast<float>(offset) + static_cast<float>(round(value/scale))),
39                                             static_cast<float>(min)), static_cast<float>(max));
40     auto quantizedBits = static_cast<QuantizedType>(clampedValue);
41 
42     return quantizedBits;
43 }
44 
45 template <typename QuantizedType>
Dequantize(QuantizedType value,float scale,int32_t offset)46 float armnn::Dequantize(QuantizedType value, float scale, int32_t offset)
47 {
48     static_assert(IsQuantizedType<QuantizedType>(), "Not an integer type.");
49     ARMNN_ASSERT(scale != 0.f);
50     ARMNN_ASSERT(!IsNan(value));
51     return (armnn::numeric_cast<float>(value - offset)) * scale;
52 }
53 
54 /// Explicit specialization of Quantize for int8_t
55 template
56 int8_t armnn::Quantize<int8_t>(float value, float scale, int32_t offset);
57 
58 /// Explicit specialization of Quantize for uint8_t
59 template
60 uint8_t armnn::Quantize<uint8_t>(float value, float scale, int32_t offset);
61 
62 /// Explicit specialization of Quantize for int16_t
63 template
64 int16_t armnn::Quantize<int16_t>(float value, float scale, int32_t offset);
65 
66 /// Explicit specialization of Quantize for int32_t
67 template
68 int32_t armnn::Quantize<int32_t>(float value, float scale, int32_t offset);
69 
70 /// Explicit specialization of Dequantize for int8_t
71 template
72 float armnn::Dequantize<int8_t>(int8_t value, float scale, int32_t offset);
73 
74 /// Explicit specialization of Dequantize for uint8_t
75 template
76 float armnn::Dequantize<uint8_t>(uint8_t value, float scale, int32_t offset);
77 
78 /// Explicit specialization of Dequantize for int16_t
79 template
80 float armnn::Dequantize<int16_t>(int16_t value, float scale, int32_t offset);
81 
82 /// Explicit specialization of Dequantize for int32_t
83 template
84 float armnn::Dequantize<int32_t>(int32_t value, float scale, int32_t offset);
85 
86 /// Explicit specialization of Dequantize for int64_t
87 template
88 float armnn::Dequantize<int64_t>(int64_t value, float scale, int32_t offset);
89