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#include "libm.h"
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
long double nextafterl(long double x, long double y)
{
return nextafter(x, y);
}
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
long double nextafterl(long double x, long double y)
{
union ldshape ux, uy;
if (isnan(x) || isnan(y))
return x + y;
if (x == y)
return y;
ux.f = x;
if (x == 0) {
uy.f = y;
ux.i.m = 1;
ux.i.se = uy.i.se & 0x8000;
} else if ((x < y) == !(ux.i.se & 0x8000)) {
ux.i.m++;
if (ux.i.m << 1 == 0) {
ux.i.m = 1ULL << 63;
ux.i.se++;
}
} else {
if (ux.i.m << 1 == 0) {
ux.i.se--;
if (ux.i.se)
ux.i.m = 0;
}
ux.i.m--;
}
/* raise overflow if ux is infinite and x is finite */
if ((ux.i.se & 0x7fff) == 0x7fff)
return x + x;
/* raise underflow if ux is subnormal or zero */
if ((ux.i.se & 0x7fff) == 0)
FORCE_EVAL(x*x + ux.f*ux.f);
return ux.f;
}
#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
long double nextafterl(long double x, long double y)
{
union ldshape ux, uy;
if (isnan(x) || isnan(y))
return x + y;
if (x == y)
return y;
ux.f = x;
if (x == 0) {
uy.f = y;
ux.i.lo = 1;
ux.i.se = uy.i.se & 0x8000;
} else if ((x < y) == !(ux.i.se & 0x8000)) {
ux.i2.lo++;
if (ux.i2.lo == 0)
ux.i2.hi++;
} else {
if (ux.i2.lo == 0)
ux.i2.hi--;
ux.i2.lo--;
}
/* raise overflow if ux is infinite and x is finite */
if ((ux.i.se & 0x7fff) == 0x7fff)
return x + x;
/* raise underflow if ux is subnormal or zero */
if ((ux.i.se & 0x7fff) == 0)
FORCE_EVAL(x*x + ux.f*ux.f);
return ux.f;
}
#endif
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