1#ifndef TESTS_IS_QUIET_NAN_H
2#define TESTS_IS_QUIET_NAN_H
3
4namespace flatbuffers {
5namespace tests {
6
7#if defined(FLATBUFFERS_HAS_NEW_STRTOD) && (FLATBUFFERS_HAS_NEW_STRTOD > 0)
8// The IEEE-754 quiet_NaN is not simple binary constant.
9// All binary NaN bit strings have all the bits of the biased exponent field E
10// set to 1. A quiet NaN bit string should be encoded with the first bit d[1]
11// of the trailing significand field T being 1 (d[0] is implicit bit).
12// It is assumed that endianness of floating-point is same as integer.
13template<typename T, typename U, U qnan_base> bool is_quiet_nan_impl(T v) {
14 static_assert(sizeof(T) == sizeof(U), "unexpected");
15 U b = 0;
16 std::memcpy(&b, &v, sizeof(T));
17 return ((b & qnan_base) == qnan_base);
18}
19# if defined(__mips__) || defined(__hppa__)
20inline bool is_quiet_nan(float v) {
21 return is_quiet_nan_impl<float, uint32_t, 0x7FC00000u>(v) ||
22 is_quiet_nan_impl<float, uint32_t, 0x7FBFFFFFu>(v);
23}
24inline bool is_quiet_nan(double v) {
25 return is_quiet_nan_impl<double, uint64_t, 0x7FF8000000000000ul>(v) ||
26 is_quiet_nan_impl<double, uint64_t, 0x7FF7FFFFFFFFFFFFu>(v);
27}
28# else
29inline bool is_quiet_nan(float v) {
30 return is_quiet_nan_impl<float, uint32_t, 0x7FC00000u>(v);
31}
32inline bool is_quiet_nan(double v) {
33 return is_quiet_nan_impl<double, uint64_t, 0x7FF8000000000000ul>(v);
34}
35# endif
36#endif
37
38} // namespace tests
39} // namespace flatbuffers
40
41#endif // TESTS_IS_QUIET_NAN_H
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