1 /* Return the least floating-point number greater than X.
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 <float.h>
20 #include <math.h>
21 #include <math_private.h>
22 #include <libm-alias-ldouble.h>
23 
24 /* Return the least floating-point number greater than X.  */
25 long double
__nextupl(long double x)26 __nextupl (long double x)
27 {
28   uint32_t hx, ix;
29   uint32_t lx;
30   int32_t esx;
31 
32   GET_LDOUBLE_WORDS (esx, hx, lx, x);
33   ix = esx & 0x7fff;
34 
35   if (((ix == 0x7fff) && (((hx & 0x7fffffff) | lx) != 0)))  /* x is nan.  */
36     return x + x;
37   if ((ix | hx | lx) == 0)
38     return LDBL_TRUE_MIN;
39   if (esx >= 0)
40     {				/* x > 0.  */
41       if (isinf (x))
42         return x;
43       lx += 1;
44       if (lx == 0)
45         {
46           hx += 1;
47 #if LDBL_MIN_EXP == -16381
48           if (hx == 0 || (esx == 0 && hx == 0x80000000))
49 #else
50           if (hx == 0)
51 #endif
52           {
53             esx += 1;
54             hx |= 0x80000000;
55           }
56         }
57     }
58   else
59     {				/* x < 0.  */
60       if (lx == 0)
61         {
62 #if LDBL_MIN_EXP == -16381
63           if (hx <= 0x80000000 && esx != 0xffff8000)
64             {
65               esx -= 1;
66               hx = hx - 1;
67               if ((esx & 0x7fff) > 0)
68                 hx |= 0x80000000;
69             }
70           else
71             hx -= 1;
72 #else
73           if (ix != 0 && hx == 0x80000000)
74             hx = 0;
75           if (hx == 0)
76             esx -= 1;
77           hx -= 1;
78 #endif
79         }
80       lx -= 1;
81     }
82   SET_LDOUBLE_WORDS (x, esx, hx, lx);
83   return x;
84 }
85 
86 libm_alias_ldouble (__nextup, nextup)
87