src/math/__fpclassify.c

570af302Sopenharmony_ci#include <math.h>
570af302Sopenharmony_ci#include <stdint.h>
570af302Sopenharmony_ci
570af302Sopenharmony_ciint __fpclassify(double x)
570af302Sopenharmony_ci{
570af302Sopenharmony_ci	union {double f; uint64_t i;} u = {x};
570af302Sopenharmony_ci	int e = u.i>>52 & 0x7ff;
570af302Sopenharmony_ci	if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO;
570af302Sopenharmony_ci	if (e==0x7ff) return u.i<<12 ? FP_NAN : FP_INFINITE;
570af302Sopenharmony_ci	return FP_NORMAL;
570af302Sopenharmony_ci}