Compute Library
 21.02
float_ops.h
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1 /*
2  * Copyright (c) 2019-2020 Arm Limited.
3  *
4  * SPDX-License-Identifier: MIT
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24 #ifndef ARM_COMPUTE_UTILS_HELPERS_FLOAT_OPS_H
25 #define ARM_COMPUTE_UTILS_HELPERS_FLOAT_OPS_H
26 
27 namespace arm_compute
28 {
29 namespace helpers
30 {
31 namespace float_ops
32 {
33 union RawFloat
34 {
35  /** Constructor
36  *
37  * @param[in] val Floating-point value
38  */
39  explicit RawFloat(float val)
40  : f32(val)
41  {
42  }
43  /** Extract sign of floating point number
44  *
45  * @return Sign of floating point number
46  */
47  int32_t sign() const
48  {
49  return i32 >> 31;
50  }
51  /** Extract exponent of floating point number
52  *
53  * @return Exponent of floating point number
54  */
55  int32_t exponent() const
56  {
57  return (i32 >> 23) & 0xFF;
58  }
59  /** Extract mantissa of floating point number
60  *
61  * @return Mantissa of floating point number
62  */
63  int32_t mantissa() const
64  {
65  return i32 & 0x007FFFFF;
66  }
67 
68  int32_t i32;
69  float f32;
70 };
71 
72 /** Checks if two floating point numbers are equal given an allowed number of ULPs
73  *
74  * @param[in] a First number to compare
75  * @param[in] b Second number to compare
76  * @param[in] max_allowed_ulps (Optional) Number of allowed ULPs
77  *
78  * @return True if number is close else false
79  */
80 inline bool is_equal_ulps(float a, float b, int max_allowed_ulps = 0)
81 {
82  RawFloat ra(a);
83  RawFloat rb(b);
84 
85  // Check ULP distance
86  const int ulps = std::abs(ra.i32 - rb.i32);
87  return ulps <= max_allowed_ulps;
88 }
89 
90 /** Checks if the input floating point number is 1.0f checking if the difference is within a range defined with epsilon
91  *
92  * @param[in] a Input floating point number
93  * @param[in] epsilon (Optional) Epsilon used to define the error bounds
94  *
95  * @return True if number is close to 1.0f
96  */
97 inline bool is_one(float a, float epsilon = 0.00001f)
98 {
99  return std::abs(1.0f - a) <= epsilon;
100 }
101 
102 /** Checks if the input floating point number is 0.0f checking if the difference is within a range defined with epsilon
103  *
104  * @param[in] a Input floating point number
105  * @param[in] epsilon (Optional) Epsilon used to define the error bounds
106  *
107  * @return True if number is close to 0.0f
108  */
109 inline bool is_zero(float a, float epsilon = 0.00001f)
110 {
111  return std::abs(0.0f - a) <= epsilon;
112 }
113 } // namespace float_ops
114 } // namespace helpers
115 } // namespace arm_compute
116 #endif /* ARM_COMPUTE_UTILS_HELPERS_FLOAT_OPS_H */
bool is_one(float a, float epsilon=0.00001f)
Checks if the input floating point number is 1.0f checking if the difference is within a range define...
Definition: float_ops.h:97
int32_t exponent() const
Extract exponent of floating point number.
Definition: float_ops.h:55
SimpleTensor< float > b
Definition: DFT.cpp:157
bool is_equal_ulps(float a, float b, int max_allowed_ulps=0)
Checks if two floating point numbers are equal given an allowed number of ULPs.
Definition: float_ops.h:80
Copyright (c) 2017-2021 Arm Limited.
RawFloat(float val)
Constructor.
Definition: float_ops.h:39
int32_t mantissa() const
Extract mantissa of floating point number.
Definition: float_ops.h:63
bool is_zero(float a, float epsilon=0.00001f)
Checks if the input floating point number is 0.0f checking if the difference is within a range define...
Definition: float_ops.h:109
int32_t sign() const
Extract sign of floating point number.
Definition: float_ops.h:47