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Diffstat (limited to 'sysdeps/ieee754/flt-32/w_ilogbf-impl.h')
-rw-r--r--sysdeps/ieee754/flt-32/w_ilogbf-impl.h38
1 files changed, 38 insertions, 0 deletions
diff --git a/sysdeps/ieee754/flt-32/w_ilogbf-impl.h b/sysdeps/ieee754/flt-32/w_ilogbf-impl.h
new file mode 100644
index 0000000..5aa8bf0
--- /dev/null
+++ b/sysdeps/ieee754/flt-32/w_ilogbf-impl.h
@@ -0,0 +1,38 @@
+/* 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 (float x)
+{
+ uint32_t ux = asuint (x);
+ int ex = (ux & ~SIGN_MASK) >> MANTISSA_WIDTH;
+ if (__glibc_unlikely (ex == 0))
+ {
+ /* Zero or subnormal.
+ Clear sign and exponent. */
+ ux <<= 1 + EXPONENT_WIDTH;
+ if (ux == 0)
+ return RET_INVALID (RET_LOGB0);
+ /* subnormal */
+ return (RET_TYPE)-127 - stdc_leading_zeros (ux);
+ }
+ if (__glibc_unlikely (ex == EXPONENT_MASK >> MANTISSA_WIDTH))
+ /* NaN or Inf */
+ return RET_INVALID (ux << (1 + EXPONENT_WIDTH) ? RET_LOGBNAN : RET_LOGMAX);
+ return ex - 127;
+}