ie_precision.hpp
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1 // Copyright (C) 2018-2019 Intel Corporation
2 // SPDX-License-Identifier: Apache-2.0
3 //
4 
5 /**
6  * @brief A header file that provides class for describing precision of data
7  * @file ie_precision.hpp
8  */
9 #pragma once
10 #include <unordered_map>
11 #include <string>
12 #include "details/ie_exception.hpp"
13 
14 namespace InferenceEngine {
15 
16 /**
17  * @brief This class holds precision value and provides precision related operations
18  */
19 class Precision {
20 public:
21  /** Enum to specify of different */
22  enum ePrecision : uint8_t {
23  UNSPECIFIED = 255, /**< Unspecified value. Used by default */
24  MIXED = 0, /**< Mixed value. Can be received from network. No applicable for tensors */
25  FP32 = 10, /**< 32bit floating point value */
26  FP16 = 11, /**< 16bit floating point value */
27  Q78 = 20, /**< 16bit specific signed fixed point precision */
28  I16 = 30, /**< 16bit signed integer value */
29  U8 = 40, /**< 8bit unsigned integer value */
30  I8 = 50, /**< 8bit signed integer value */
31  U16 = 60, /**< 16bit unsigned integer value */
32  I32 = 70, /**< 32bit signed integer value */
33  BIN = 71, /**< 1bit integer value */
34  CUSTOM = 80 /**< custom precision has it's own name and size of elements */
35  };
36 
37 private:
38  struct PrecisionInfo {
39  /** @brief Size of underlined element */
40  size_t bitsSize = 0;
41 
42  /** @brief Null terminated string with precision name */
43  const char *name = "UNSPECIFIED";
44 
45  bool isFloat = false;
46  ePrecision value = Precision::UNSPECIFIED;
47  };
48  PrecisionInfo precisionInfo;
49 
50 public:
51  /** @brief Default constructor */
52  Precision() = default;
53 
54  /** @brief Constructor with specified precision */
55  Precision(const Precision::ePrecision value) { // NOLINT
56  precisionInfo = getPrecisionInfo(value);
57  }
58 
59  /**
60  * @brief Custom precision constructor
61  * @param byteSize size of elements
62  * @param name optional name string, used in serialisation
63  */
64  explicit Precision(size_t bitsSize, const char * name = nullptr) {
65  if (bitsSize == 0) {
66  THROW_IE_EXCEPTION << "Precision with 0 elements size not supported";
67  }
68  precisionInfo.bitsSize = bitsSize;
69  if (name == nullptr) {
70  precisionInfo.name = "CUSTOM";
71  } else {
72  precisionInfo.name = name;
73  }
74  precisionInfo.value = CUSTOM;
75  }
76 
77  /** @brief Creates custom precision with specific underlined type */
78  template <class T>
79  static Precision fromType(const char * typeName = nullptr) {
80  return Precision(8 * sizeof(T), typeName == nullptr ? typeid(T).name() : typeName);
81  }
82 
83  /** @brief checks whether given storage class T can be used to store objects of current precision */
84  template <class T>
85  bool hasStorageType(const char * typeName = nullptr) const noexcept {
86  try {
87  if (precisionInfo.value != BIN) {
88  if (sizeof(T) != size()) {
89  return false;
90  }
91  }
92 #define CASE(x, y) case x: return std::is_same<T, y>()
93 #define CASE2(x, y1, y2) case x: return std::is_same<T, y1>() || std::is_same<T, y2>()
94 
95  switch (precisionInfo.value) {
96  CASE(FP32, float);
97  CASE2(FP16, int16_t, uint16_t);
98  CASE(I16, int16_t);
99  CASE(I32, int32_t);
100  CASE(U16, uint16_t);
101  CASE(U8, uint8_t);
102  CASE(I8, int8_t);
103  CASE2(Q78, int16_t, uint16_t);
104  CASE2(BIN, int8_t, uint8_t);
105  default :
106  return areSameStrings(name(), typeName == nullptr ? typeid(T).name() : typeName);
107 #undef CASE
108 #undef CASE2
109  }
110  } catch (...) {
111  return false;
112  }
113  }
114 
115  /** @brief Equality operator with Precision object */
116  bool operator == (const Precision & p) const noexcept {
117  return precisionInfo.value == p &&
118  precisionInfo.bitsSize == p.precisionInfo.bitsSize &&
119  areSameStrings(precisionInfo.name, p.precisionInfo.name);
120  }
121 
122  /** @brief Equality operator with ePrecision enum value */
123  bool operator == (const ePrecision p) const noexcept {
124  return precisionInfo.value == p;
125  }
126 
127  /** @brief Inequality operator with ePrecision enum value */
128  bool operator != (const ePrecision p) const noexcept {
129  return precisionInfo.value != p;
130  }
131 
132  /** @brief Assignment operator with ePrecision enum value */
133  Precision & operator = (const ePrecision p) noexcept {
134  precisionInfo = getPrecisionInfo(p);
135  return *this;
136  }
137 
138  /** @brief Cast operator to a bool */
139  explicit operator bool() const noexcept {
140  return precisionInfo.value != UNSPECIFIED;
141  }
142 
143  /** @brief Logical negation operator */
144  bool operator !() const noexcept {
145  return precisionInfo.value == UNSPECIFIED;
146  }
147 
148  /** @brief Cast operator to a ePrecision */
149  operator Precision::ePrecision () const noexcept {
150  return precisionInfo.value;
151  }
152 
153  /** @brief Getter of precision name */
154  const char *name() const noexcept {
155  return precisionInfo.name;
156  }
157 
158  /** @brief Creates from string with precision name */
159  static Precision FromStr(const std::string &str) {
160  static std::unordered_map<std::string, ePrecision > names = {
161 #define PRECISION_NAME(s) {#s, s}
162  PRECISION_NAME(Q78),
163  PRECISION_NAME(U8),
164  PRECISION_NAME(I8),
165  PRECISION_NAME(I16),
166  PRECISION_NAME(I32),
167  PRECISION_NAME(U16),
168  PRECISION_NAME(FP32),
169  PRECISION_NAME(FP16),
170  PRECISION_NAME(MIXED),
171  PRECISION_NAME(BIN),
172 #undef PRECISION_NAME
173  };
174  auto i = names.find(str);
175  return i == names.end() ? Precision() : Precision(i->second);
176  }
177 
178  /**
179  * @brief Returns size in bytes of single element of that precision
180  * @deprecated : size of precision will be reported in bits in future releases
181  */
182  size_t size() const {
183  if (precisionInfo.bitsSize == 0) {
184  THROW_IE_EXCEPTION << " cannot estimate element if precision is " << precisionInfo.name;
185  }
186  return precisionInfo.bitsSize >> 3;
187  }
188 
189  /** @brief Checks if it is a floating point */
190  bool is_float() const noexcept {
191  return precisionInfo.isFloat;
192  }
193 
194  protected:
195  template<Precision::ePrecision precision>
196  static PrecisionInfo makePrecisionInfo(const char * name);
197 
198  static bool areSameStrings(const char *l, const char *r) noexcept {
199  if (l == r)
200  return true;
201 
202  if (l == nullptr || r == nullptr)
203  return false;
204 
205  for (; *l && *r; l++, r++) {
206  if (*l != *r) return false;
207  }
208  return *l == *r;
209  }
210 
211  static PrecisionInfo getPrecisionInfo(ePrecision v) {
212 #define CASE(x) case x: return makePrecisionInfo<x>(#x);
213  switch (v) {
214  CASE(FP32);
215  CASE(FP16);
216  CASE(I16);
217  CASE(I32);
218  CASE(U16);
219  CASE(U8);
220  CASE(I8);
221  CASE(Q78);
222  CASE(MIXED);
223  CASE(BIN);
224  default : return makePrecisionInfo<UNSPECIFIED>("UNSPECIFIED");
225 #undef CASE
226  }
227  }
228 };
229 
230 /**
231  * @brief Particular precision traits
232  */
233 template<Precision::ePrecision p>
234 struct PrecisionTrait {
235 };
236 
237 /** @cond INTERNAL */
238 template<>
239 struct PrecisionTrait<Precision::FP32> {
240  using value_type = float;
241 };
242 
243 template<>
244 struct PrecisionTrait<Precision::FP16> {
245  using value_type = int16_t;
246 };
247 template<>
248 struct PrecisionTrait<Precision::Q78> {
249  using value_type = uint16_t;
250 };
251 template<>
252 struct PrecisionTrait<Precision::I16> {
253  using value_type = int16_t;
254 };
255 template<>
256 struct PrecisionTrait<Precision::U16> {
257  using value_type = uint16_t;
258 };
259 template<>
260 struct PrecisionTrait<Precision::U8> {
261  using value_type = uint8_t;
262 };
263 template<>
264 struct PrecisionTrait<Precision::I8> {
265  using value_type = int8_t;
266 };
267 template<>
268 struct PrecisionTrait<Precision::I32> {
269  using value_type = int32_t;
270 };
271 template<>
272 struct PrecisionTrait<Precision::BIN> {
273  using value_type = int8_t;
274 };
275 
276 template<class T>
277 inline uint8_t type_size_or_zero() {
278  return sizeof(T);
279 }
280 
281 template<>
282 struct PrecisionTrait<Precision::UNSPECIFIED> {
283  using value_type = void;
284 };
285 
286 template<>
287 struct PrecisionTrait<Precision::MIXED> : PrecisionTrait<Precision::UNSPECIFIED>{
288 };
289 
290 template<>
291 inline uint8_t type_size_or_zero<void>() {
292  return 0;
293 }
294 
295 template<Precision::ePrecision T>
296 inline typename std::enable_if<std::is_same<
297  std::integral_constant<Precision::ePrecision, Precision::FP16>,
298  std::integral_constant<Precision::ePrecision, T>>::value, bool>::type is_floating() {
299  return true;
300 }
301 
302 template<Precision::ePrecision T>
303 inline typename std::enable_if<!std::is_same<
304  std::integral_constant<Precision::ePrecision, Precision::FP16>,
305  std::integral_constant<Precision::ePrecision, T>>::value, bool>::type is_floating() {
306  return std::is_floating_point<typename PrecisionTrait<T>::value_type>::value;
307 }
308 
309 template<Precision::ePrecision precision>
310 inline Precision::PrecisionInfo Precision::makePrecisionInfo(const char *name) {
311  Precision::PrecisionInfo info;
312  info.name = name;
313 
314  size_t nBits = precision == BIN ? 1 : 8;
315  info.bitsSize = nBits * type_size_or_zero<typename PrecisionTrait<precision>::value_type>();
316  info.isFloat = is_floating<precision>();
317  info.value = precision;
318  return info;
319 }
320 
321 inline std::ostream & operator << (std::ostream &out, const InferenceEngine::Precision & p) {
322  return out << p.name();
323 }
324 
325 inline std::ostream & operator << (std::ostream &out, const InferenceEngine::Precision::ePrecision & p) {
326  return out << Precision(p).name();
327 }
328 
329 /** @endcond */
330 
331 } // namespace InferenceEngine
THROW_IE_EXCEPTION
#define THROW_IE_EXCEPTION
A macro used to throw the exception with a notable description.
Definition: ie_exception.hpp:22
InferenceEngine::Precision::U16
Definition: ie_precision.hpp:31
InferenceEngine::Precision::FP32
Definition: ie_precision.hpp:25
InferenceEngine::Precision::ePrecision
ePrecision
Definition: ie_precision.hpp:22
InferenceEngine::PrecisionTrait
Particular precision traits.
Definition: ie_precision.hpp:234
InferenceEngine::Precision::fromType
static Precision fromType(const char *typeName=nullptr)
Creates custom precision with specific underlined type.
Definition: ie_precision.hpp:79
InferenceEngine
Definition: ie_argmax_layer.hpp:11
InferenceEngine::Precision::I8
Definition: ie_precision.hpp:30
InferenceEngine::Precision::operator!
bool operator!() const noexcept
Logical negation operator.
Definition: ie_precision.hpp:144
InferenceEngine::Precision::operator=
Precision & operator=(const ePrecision p) noexcept
Assignment operator with ePrecision enum value.
Definition: ie_precision.hpp:133
InferenceEngine::Precision::Q78
Definition: ie_precision.hpp:27
InferenceEngine::Precision::size
size_t size() const
Returns size in bytes of single element of that precision.
Definition: ie_precision.hpp:182
InferenceEngine::Precision::FP16
Definition: ie_precision.hpp:26
InferenceEngine::Precision::operator==
bool operator==(const Precision &p) const noexcept
Equality operator with Precision object.
Definition: ie_precision.hpp:116
InferenceEngine::Precision::BIN
Definition: ie_precision.hpp:33
InferenceEngine::Precision::is_float
bool is_float() const noexcept
Checks if it is a floating point.
Definition: ie_precision.hpp:190
InferenceEngine::Precision::CUSTOM
Definition: ie_precision.hpp:34
InferenceEngine::Precision::FromStr
static Precision FromStr(const std::string &str)
Creates from string with precision name.
Definition: ie_precision.hpp:159
InferenceEngine::Precision::Precision
Precision(size_t bitsSize, const char *name=nullptr)
Custom precision constructor.
Definition: ie_precision.hpp:64
InferenceEngine::Precision::U8
Definition: ie_precision.hpp:29
InferenceEngine::Precision::MIXED
Definition: ie_precision.hpp:24
InferenceEngine::Precision::I32
Definition: ie_precision.hpp:32
InferenceEngine::Precision::I16
Definition: ie_precision.hpp:28
InferenceEngine::Precision::Precision
Precision(const Precision::ePrecision value)
Constructor with specified precision.
Definition: ie_precision.hpp:55
InferenceEngine::Precision::operator!=
bool operator!=(const ePrecision p) const noexcept
Inequality operator with ePrecision enum value.
Definition: ie_precision.hpp:128
InferenceEngine::Precision::Precision
Precision()=default
Default constructor.
ie_exception.hpp
A header file for the main Inference Engine exception.
InferenceEngine::Precision
This class holds precision value and provides precision related operations.
Definition: ie_precision.hpp:19
InferenceEngine::Precision::UNSPECIFIED
Definition: ie_precision.hpp:23
InferenceEngine::Precision::hasStorageType
bool hasStorageType(const char *typeName=nullptr) const noexcept
checks whether given storage class T can be used to store objects of current precision ...
Definition: ie_precision.hpp:85
InferenceEngine::Precision::name
const char * name() const noexcept
Getter of precision name.
Definition: ie_precision.hpp:154