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#include <limits.h>
#include "libm.h"
int ilogb(double x)
{
union dshape u = {x};
int e = u.bits>>52 & 0x7ff;
if (!e) {
u.bits <<= 12;
if (u.bits == 0) {
FORCE_EVAL(0/0.0f);
return FP_ILOGB0;
}
/* subnormal x */
for (e = -0x3ff; u.bits < (uint64_t)1<<63; e--, u.bits<<=1);
return e;
}
if (e == 0x7ff) {
FORCE_EVAL(0/0.0f);
return u.bits<<12 ? FP_ILOGBNAN : INT_MAX;
}
return e - 0x3ff;
}
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