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#include <limits.h>
#include "libm.h"
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
int ilogbl(long double x)
{
return ilogb(x);
}
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
int ilogbl(long double x)
{
union ldshape u = {x};
uint64_t m = u.bits.m;
int e = u.bits.exp;
if (!e) {
if (m == 0)
return FP_ILOGB0;
/* subnormal x */
for (e = -0x3fff+1; m < (uint64_t)1<<63; e--, m<<=1);
return e;
}
if (e == 0x7fff)
/* in ld80 msb is set in inf */
return m & (uint64_t)-1>>1 ? FP_ILOGBNAN : INT_MAX;
return e - 0x3fff;
}
#endif
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