1#include "libm.h"
2
3float nextafterf(float x, float y)
4{
5 union {float f; uint32_t i;} ux={x}, uy={y};
6 uint32_t ax, ay, e;
7
8 if (isnan(x) || isnan(y))
9 return x + y;
10 if (ux.i == uy.i)
11 return y;
12 ax = ux.i & 0x7fffffff;
13 ay = uy.i & 0x7fffffff;
14 if (ax == 0) {
15 if (ay == 0)
16 return y;
17 ux.i = (uy.i & 0x80000000) | 1;
18 } else if (ax > ay || ((ux.i ^ uy.i) & 0x80000000))
19 ux.i--;
20 else
21 ux.i++;
22 e = ux.i & 0x7f800000;
23 /* raise overflow if ux.f is infinite and x is finite */
24 if (e == 0x7f800000)
25 FORCE_EVAL(x+x);
26 /* raise underflow if ux.f is subnormal or zero */
27 if (e == 0)
28 FORCE_EVAL(x*x + ux.f*ux.f);
29 return ux.f;
30}