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I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
65 lines
2.1 KiB
C
65 lines
2.1 KiB
C
/* Get exponent of a floating-point value. PowerPC version.
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Copyright (C) 2012-2022 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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/* ISA 2.07 provides fast GPR to FP instruction (mfvsr{d,wz}) which make
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generic implementation faster. */
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#if defined(_ARCH_PWR8) || !defined(_ARCH_PWR7)
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# include <sysdeps/ieee754/dbl-64/s_logb.c>
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#else
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# include <math.h>
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# include <math_private.h>
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# include <math_ldbl_opt.h>
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# include <libm-alias-double.h>
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/* This implementation avoids FP to INT conversions by using VSX
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bitwise instructions over FP values. */
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double
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__logb (double x)
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{
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double ret;
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if (__glibc_unlikely (x == 0.0))
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/* Raise FE_DIVBYZERO and return -HUGE_VAL[LF]. */
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return -1.0 / fabs (x);
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/* Mask to extract the exponent. */
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asm ("xxland %x0,%x1,%x2\n"
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"fcfid %0,%0"
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: "=d" (ret)
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: "d" (x), "d" (0x7ff0000000000000ULL));
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ret = (ret * 0x1p-52) - 1023.0;
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if (ret > 1023.0)
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/* Multiplication is used to set logb (+-INF) = INF. */
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return (x * x);
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else if (ret == -1023.0)
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{
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/* POSIX specifies that denormal numbers are treated as
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though they were normalized. */
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int64_t ix;
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EXTRACT_WORDS64 (ix, x);
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ix &= UINT64_C (0x7fffffffffffffff);
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return (double) (-1023 - (__builtin_clzll (ix) - 12));
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}
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/* Test to avoid logb_downward (0.0) == -0.0. */
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return ret == -0.0 ? 0.0 : ret;
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}
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# ifndef __logb
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libm_alias_double (__logb, logb)
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# endif
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#endif
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