glibc/sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c

95 lines
3.1 KiB
C

/* Return classification value corresponding to argument.
Copyright (C) 1997-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
Jakub Jelinek <jj@ultra.linux.cz>, 1999.
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.h>
#include <math_private.h>
#include <math_ldbl_opt.h>
/*
* hx lx
* +NaN 7ffn nnnn nnnn nnnn xxxx xxxx xxxx xxxx
* -NaN fffn nnnn nnnn nnnn xxxx xxxx xxxx xxxx
* +Inf 7ff0 0000 0000 0000 xxxx xxxx xxxx xxxx
* -Inf fff0 0000 0000 0000 xxxx xxxx xxxx xxxx
* +0 0000 0000 0000 0000 xxxx xxxx xxxx xxxx
* -0 8000 0000 0000 0000 xxxx xxxx xxxx xxxx
* +normal 0360 0000 0000 0000 0000 0000 0000 0000 (smallest)
* -normal 8360 0000 0000 0000 0000 0000 0000 0000 (smallest)
* +normal 7fef ffff ffff ffff 7c8f ffff ffff fffe (largest)
* +normal ffef ffff ffff ffff fc8f ffff ffff fffe (largest)
* +denorm 0360 0000 0000 0000 8000 0000 0000 0001 (largest)
* -denorm 8360 0000 0000 0000 0000 0000 0000 0001 (largest)
* +denorm 000n nnnn nnnn nnnn xxxx xxxx xxxx xxxx
* -denorm 800n nnnn nnnn nnnn xxxx xxxx xxxx xxxx
*/
int
___fpclassifyl (long double x)
{
u_int64_t hx, lx;
int retval = FP_NORMAL;
GET_LDOUBLE_WORDS64 (hx, lx, x);
if ((hx & 0x7ff0000000000000ULL) == 0x7ff0000000000000ULL) {
/* +/-NaN or +/-Inf */
if (hx & 0x000fffffffffffffULL) {
/* +/-NaN */
retval = FP_NAN;
} else {
retval = FP_INFINITE;
}
} else {
/* +/-zero or +/- normal or +/- denormal */
if (hx & 0x7fffffffffffffffULL) {
/* +/- normal or +/- denormal */
if ((hx & 0x7ff0000000000000ULL) > 0x0360000000000000ULL) {
/* +/- normal */
retval = FP_NORMAL;
} else {
if ((hx & 0x7ff0000000000000ULL) == 0x0360000000000000ULL) {
if ((lx & 0x7fffffffffffffff) /* lower is non-zero */
&& ((lx^hx) & 0x8000000000000000ULL)) { /* and sign differs */
/* +/- denormal */
retval = FP_SUBNORMAL;
} else {
/* +/- normal */
retval = FP_NORMAL;
}
} else {
/* +/- denormal */
retval = FP_SUBNORMAL;
}
}
} else {
/* +/- zero */
retval = FP_ZERO;
}
}
return retval;
}
long_double_symbol (libm, ___fpclassifyl, __fpclassifyl);
#ifdef __LONG_DOUBLE_MATH_OPTIONAL
libm_hidden_ver (___fpclassifyl, __fpclassifyl)
#else
libm_hidden_def (__fpclassifyl)
#endif