1 /* Truncate argument to nearest integral value not larger than the argument.
2    Copyright (C) 1997-2022 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 #define NO_MATH_REDIRECT
20 #include <math.h>
21 
22 #include <math_private.h>
23 #include <libm-alias-float.h>
24 #include <math-use-builtins.h>
25 
26 
27 float
__truncf(float x)28 __truncf (float x)
29 {
30 #if USE_TRUNCF_BUILTIN
31   return __builtin_truncf (x);
32 #else
33   /* Use generic implementation.  */
34   int32_t i0, j0;
35   int sx;
36 
37   GET_FLOAT_WORD (i0, x);
38   sx = i0 & 0x80000000;
39   j0 = ((i0 >> 23) & 0xff) - 0x7f;
40   if (j0 < 23)
41     {
42       if (j0 < 0)
43 	/* The magnitude of the number is < 1 so the result is +-0.  */
44 	SET_FLOAT_WORD (x, sx);
45       else
46 	SET_FLOAT_WORD (x, sx | (i0 & ~(0x007fffff >> j0)));
47     }
48   else
49     {
50       if (j0 == 0x80)
51 	/* x is inf or NaN.  */
52 	return x + x;
53     }
54 
55   return x;
56 #endif /* ! USE_TRUNCF_BUILTIN  */
57 }
58 #ifndef __truncf
59 libm_alias_float (__trunc, trunc)
60 #endif
61