diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/math_err.c')
-rw-r--r-- | sysdeps/ieee754/dbl-64/math_err.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/math_err.c b/sysdeps/ieee754/dbl-64/math_err.c new file mode 100644 index 0000000..efd7ef0 --- /dev/null +++ b/sysdeps/ieee754/dbl-64/math_err.c @@ -0,0 +1,92 @@ +/* Double-precision math error handling. + Copyright (C) 2018 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 + <http://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 + +/* 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; +} |