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#include "libm.h"
float nextafterf(float x, float y)
{
union {float f; uint32_t i;} ux={x}, uy={y};
uint32_t ax, ay, e;
if (isnan(x) || isnan(y))
return x + y;
if (ux.i == uy.i)
return y;
ax = ux.i & 0x7fffffff;
ay = uy.i & 0x7fffffff;
if (ax == 0) {
if (ay == 0)
return y;
ux.i = (uy.i & 0x80000000) | 1;
} else if (ax > ay || ((ux.i ^ uy.i) & 0x80000000))
ux.i--;
else
ux.i++;
e = ux.i & 0x7f800000;
/* raise overflow if ux.f is infinite and x is finite */
if (e == 0x7f800000)
FORCE_EVAL(x+x);
/* raise underflow if ux.f is subnormal or zero */
if (e == 0)
FORCE_EVAL(x*x + ux.f*ux.f);
return ux.f;
}
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