mirror of https://gitee.com/openkylin/glibc.git
80 lines
2.7 KiB
C
80 lines
2.7 KiB
C
/* Check for underflow and force underflow exceptions.
|
|
Copyright (C) 2015-2022 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/>. */
|
|
|
|
#ifndef _MATH_UNDERFLOW_H
|
|
#define _MATH_UNDERFLOW_H 1
|
|
|
|
#include <float.h>
|
|
#include <math.h>
|
|
|
|
#include <math-barriers.h>
|
|
|
|
#define fabs_tg(x) __MATH_TG ((x), (__typeof (x)) __builtin_fabs, (x))
|
|
|
|
/* These must be function-like macros because some __MATH_TG
|
|
implementations macro-expand the function-name argument before
|
|
concatenating a suffix to it. */
|
|
#define min_of_type_f() FLT_MIN
|
|
#define min_of_type_() DBL_MIN
|
|
#define min_of_type_l() LDBL_MIN
|
|
#define min_of_type_f128() FLT128_MIN
|
|
|
|
#define min_of_type(x) __MATH_TG ((x), (__typeof (x)) min_of_type_, ())
|
|
|
|
/* If X (which is not a NaN) is subnormal, force an underflow
|
|
exception. */
|
|
#define math_check_force_underflow(x) \
|
|
do \
|
|
{ \
|
|
__typeof (x) force_underflow_tmp = (x); \
|
|
if (fabs_tg (force_underflow_tmp) \
|
|
< min_of_type (force_underflow_tmp)) \
|
|
{ \
|
|
__typeof (force_underflow_tmp) force_underflow_tmp2 \
|
|
= force_underflow_tmp * force_underflow_tmp; \
|
|
math_force_eval (force_underflow_tmp2); \
|
|
} \
|
|
} \
|
|
while (0)
|
|
/* Likewise, but X is also known to be nonnegative. */
|
|
#define math_check_force_underflow_nonneg(x) \
|
|
do \
|
|
{ \
|
|
__typeof (x) force_underflow_tmp = (x); \
|
|
if (force_underflow_tmp \
|
|
< min_of_type (force_underflow_tmp)) \
|
|
{ \
|
|
__typeof (force_underflow_tmp) force_underflow_tmp2 \
|
|
= force_underflow_tmp * force_underflow_tmp; \
|
|
math_force_eval (force_underflow_tmp2); \
|
|
} \
|
|
} \
|
|
while (0)
|
|
/* Likewise, for both real and imaginary parts of a complex
|
|
result. */
|
|
#define math_check_force_underflow_complex(x) \
|
|
do \
|
|
{ \
|
|
__typeof (x) force_underflow_complex_tmp = (x); \
|
|
math_check_force_underflow (__real__ force_underflow_complex_tmp); \
|
|
math_check_force_underflow (__imag__ force_underflow_complex_tmp); \
|
|
} \
|
|
while (0)
|
|
|
|
#endif /* math-underflow.h */
|