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3 ** Copyright (C) 2016 Intel Corporation
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24
25 #ifndef MATH_SUPPORT_H
26 #define MATH_SUPPORT_H
27
28 #include <math.h>
29
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33
34 #ifndef CBOR_NO_HALF_FLOAT_TYPE
35 /* this function was copied & adapted from RFC 7049 Appendix D */
decode_half(unsigned short half)36 static inline double decode_half(unsigned short half)
37 {
38 #ifdef __F16C__
39 return _cvtsh_ss(half);
40 #else
41 int exp = (half >> 10) & 0x1f;
42 int mant = half & 0x3ff;
43 double val;
44 if (exp == 0) val = ldexp(mant, -24);
45 else if (exp != 31) val = ldexp(mant + 1024, exp - 25);
46 else val = mant == 0 ? INFINITY : NAN;
47 return half & 0x8000 ? -val : val;
48 #endif
49 }
50 #endif
51
52 #ifdef __cplusplus
53 }
54 #endif
55
56 #endif // MATH_SUPPORT_H
57
58
