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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
#define MSB ((uint64_t)1<<63)
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.value = x;
if (x == 0) {
uy.value = y;
ux.bits.m = 1;
ux.bits.sign = uy.bits.sign;
} else if (x < y ^ ux.bits.sign) {
ux.bits.m++;
if ((ux.bits.m & ~MSB) == 0) {
ux.bits.m = MSB;
ux.bits.exp++;
}
} else {
if ((ux.bits.m & ~MSB) == 0) {
ux.bits.exp--;
if (ux.bits.exp)
ux.bits.m = 0;
}
ux.bits.m--;
}
/* raise overflow if ux.value is infinite and x is finite */
if (ux.bits.exp == 0x7fff)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
if (ux.bits.exp == 0)
FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
#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.value = x;
if (x == 0) {
uy.value = y;
ux.bits.mlo = 1;
ux.bits.sign = uy.bits.sign;
} else if (x < y ^ ux.bits.sign) {
ux.bits.mlo++;
if (ux.bits.mlo == 0) {
ux.bits.mhi++;
if (ux.bits.mhi == 0)
ux.bits.exp++;
}
} else {
if (ux.bits.mlo == 0) {
if (ux.bits.mhi == 0)
ux.bits.exp--;
ux.bits.mhi--;
}
ux.bits.mlo--;
}
/* raise overflow if ux.value is infinite and x is finite */
if (ux.bits.exp == 0x7fff)
return x + x;
/* raise underflow if ux.value is subnormal or zero */
if (ux.bits.exp == 0)
FORCE_EVAL(x*x + ux.value*ux.value);
return ux.value;
}
#endif
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