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/* Get integer exponent of a floating-point value.
Copyright (C) 1999-2025 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
static inline RET_TYPE
IMPL_NAME (double x)
{
uint64_t ux = asuint64 (x);
int ex = (ux & ~SIGN_MASK) >> MANTISSA_WIDTH;
if (__glibc_unlikely (ex == 0)) /* zero or subnormal */
{
/* Clear sign and exponent */
ux <<= 12;
if (ux == 0)
return RET_INVALID (RET_LOGB0);
/* subnormal */
return (RET_TYPE)-1023 - stdc_leading_zeros (ux);
}
if (__glibc_unlikely (ex == EXPONENT_MASK >> MANTISSA_WIDTH))
/* NaN or Inf */
return RET_INVALID (ux << 12 ? RET_LOGBNAN : RET_LOGMAX);
return ex - 1023;
}
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