glibc/sysdeps/ieee754/ldbl-128/s_totalorderl.c

55 lines
1.9 KiB
C

/* Total order operation. ldbl-128 version.
Copyright (C) 2016-2017 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.h>
#include <math_private.h>
#include <nan-high-order-bit.h>
#include <stdint.h>
int
totalorderl (_Float128 x, _Float128 y)
{
int64_t hx, hy;
uint64_t lx, ly;
GET_LDOUBLE_WORDS64 (hx, lx, x);
GET_LDOUBLE_WORDS64 (hy, ly, y);
#if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
uint64_t uhx = hx & 0x7fffffffffffffffULL;
uint64_t uhy = hy & 0x7fffffffffffffffULL;
/* For the preferred quiet NaN convention, this operation is a
comparison of the representations of the arguments interpreted as
sign-magnitude integers. If both arguments are NaNs, invert the
quiet/signaling bit so comparing that way works. */
if ((uhx > 0x7fff000000000000ULL || (uhx == 0x7fff000000000000ULL
&& lx != 0))
&& (uhy > 0x7fff000000000000ULL || (uhy == 0x7fff000000000000ULL
&& ly != 0)))
{
hx ^= 0x0000800000000000ULL;
hy ^= 0x0000800000000000ULL;
}
#endif
uint64_t hx_sign = hx >> 63;
uint64_t hy_sign = hy >> 63;
hx ^= hx_sign >> 1;
lx ^= hx_sign;
hy ^= hy_sign >> 1;
ly ^= hy_sign;
return hx < hy || (hx == hy && lx <= ly);
}