glibc/sysdeps/ieee754/dbl-64/math_err.c
Adhemerval Zanella Netto 16439f419b math: Remove the error handling wrapper from fmod and fmodf
The error handling is moved to sysdeps/ieee754 version with no SVID
support.  The compatibility symbol versions still use the wrapper
with SVID error handling around the new code.  There is no new symbol
version nor compatibility code on !LIBM_SVID_COMPAT targets
(e.g. riscv).

The ia64 is unchanged, since it still uses the arch specific
__libm_error_region on its implementation.  For both i686 and m68k,
which provive arch specific implementation, wrappers are added so
no new symbol are added (which would require to change the
implementations).

It shows an small improvement, the results for fmod:

  Architecture     | Input           | master   | patch
  -----------------|-----------------|----------|--------
  x86_64 (Ryzen 9) | subnormals      | 12.5049  | 9.40992
  x86_64 (Ryzen 9) | normal          | 296.939  | 296.738
  x86_64 (Ryzen 9) | close-exponents | 16.0244  | 13.119
  aarch64 (N1)     | subnormal       | 6.81778  | 4.33313
  aarch64 (N1)     | normal          | 155.620  | 152.915
  aarch64 (N1)     | close-exponents | 8.21306  | 5.76138
  armhf (N1)       | subnormal       | 15.1083  | 14.5746
  armhf (N1)       | normal          | 244.833  | 241.738
  armhf (N1)       | close-exponents | 21.8182  | 22.457

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Wilco Dijkstra  <Wilco.Dijkstra@arm.com>
2023-04-03 16:45:27 -03:00

99 lines
2.4 KiB
C

/* Double-precision math error handling.
Copyright (C) 2018-2023 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/>. */
#include <math-barriers.h>
#include "math_config.h"
#if WANT_ERRNO
#include <errno.h>
/* NOINLINE reduces code size and avoids making math functions non-leaf
when the error handling is inlined. */
NOINLINE static double
with_errno (double y, int e)
{
errno = e;
return y;
}
#else
#define with_errno(x, e) (x)
#endif
attribute_hidden double
__math_edom (double y)
{
return with_errno (y, EDOM);
}
/* NOINLINE reduces code size. */
NOINLINE static double
xflow (uint32_t sign, double y)
{
y = math_opt_barrier (sign ? -y : y) * y;
return with_errno (y, ERANGE);
}
attribute_hidden double
__math_uflow (uint32_t sign)
{
return xflow (sign, 0x1p-767);
}
#if WANT_ERRNO_UFLOW
/* Underflows to zero in some non-nearest rounding mode, setting errno
is valid even if the result is non-zero, but in the subnormal range. */
attribute_hidden double
__math_may_uflow (uint32_t sign)
{
return xflow (sign, 0x1.8p-538);
}
#endif
attribute_hidden double
__math_oflow (uint32_t sign)
{
return xflow (sign, 0x1p769);
}
attribute_hidden double
__math_divzero (uint32_t sign)
{
double y = math_opt_barrier (sign ? -1.0 : 1.0) / 0.0;
return with_errno (y, ERANGE);
}
attribute_hidden double
__math_invalid (double x)
{
double y = (x - x) / (x - x);
return isnan (x) ? y : with_errno (y, EDOM);
}
/* Check result and set errno if necessary. */
attribute_hidden double
__math_check_uflow (double y)
{
return y == 0.0 ? with_errno (y, ERANGE) : y;
}
attribute_hidden double
__math_check_oflow (double y)
{
return isinf (y) ? with_errno (y, ERANGE) : y;
}