1 /* Total order operation.
2    Copyright (C) 2016-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <math.h>
20 #include <math_private.h>
21 #include <nan-high-order-bit.h>
22 #include <libm-alias-double.h>
23 #include <stdint.h>
24 #include <shlib-compat.h>
25 #include <first-versions.h>
26 
27 int
__totalorder(const double * x,const double * y)28 __totalorder (const double *x, const double *y)
29 {
30   int64_t ix, iy;
31   EXTRACT_WORDS64 (ix, *x);
32   EXTRACT_WORDS64 (iy, *y);
33 #if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
34   /* For the preferred quiet NaN convention, this operation is a
35      comparison of the representations of the arguments interpreted as
36      sign-magnitude integers.  If both arguments are NaNs, invert the
37      quiet/signaling bit so comparing that way works.  */
38   if ((ix & 0x7fffffffffffffffULL) > 0x7ff0000000000000ULL
39       && (iy & 0x7fffffffffffffffULL) > 0x7ff0000000000000ULL)
40     {
41       ix ^= 0x0008000000000000ULL;
42       iy ^= 0x0008000000000000ULL;
43     }
44 #endif
45   uint64_t ix_sign = ix >> 63;
46   uint64_t iy_sign = iy >> 63;
47   ix ^= ix_sign >> 1;
48   iy ^= iy_sign >> 1;
49   return ix <= iy;
50 }
51 #ifdef SHARED
52 # define CONCATX(x, y) x ## y
53 # define CONCAT(x, y) CONCATX (x, y)
54 # define UNIQUE_ALIAS(name) CONCAT (name, __COUNTER__)
55 # define do_symbol(orig_name, name, aliasname)		\
56   strong_alias (orig_name, name)			\
57   versioned_symbol (libm, name, aliasname, GLIBC_2_31)
58 # undef weak_alias
59 # define weak_alias(name, aliasname)			\
60   do_symbol (name, UNIQUE_ALIAS (name), aliasname);
61 #endif
libm_alias_double(__totalorder,totalorder)62 libm_alias_double (__totalorder, totalorder)
63 #if SHLIB_COMPAT (libm, GLIBC_2_25, GLIBC_2_31)
64 int
65 attribute_compat_text_section
66 __totalorder_compat (double x, double y)
67 {
68   return __totalorder (&x, &y);
69 }
70 #undef do_symbol
71 #define do_symbol(orig_name, name, aliasname)			\
72   strong_alias (orig_name, name)				\
73   compat_symbol (libm, name, aliasname,				\
74 		 CONCAT (FIRST_VERSION_libm_, aliasname))
75 libm_alias_double (__totalorder_compat, totalorder)
76 #endif
77