1 /* Round double to integer away from zero.
2 Copyright (C) 2011 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 2011.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
20 /* Based on a version which carries the following copyright: */
23 * ====================================================
24 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
26 * Developed at SunPro, a Sun Microsystems, Inc. business.
27 * Permission to use, copy, modify, and distribute this
28 * software is freely granted, provided that this notice
30 * ====================================================
34 #include "math_private.h"
38 * Return x rounded toward -inf to integral value
42 * Inexact flag raised if x not equal to floor(x).
45 static const double huge
= 1.0e300
;
52 EXTRACT_WORDS64(i0
,x
);
53 int32_t j0
= ((i0
>>52)&0x7ff)-0x3ff;
54 if(__builtin_expect(j0
<52, 1)) {
55 if(j0
<0) { /* raise inexact if x != 0 */
56 math_force_eval(huge
+x
);/* return 0*sign(x) if |x|<1 */
58 else if((i0
&0x7fffffffffffffffl
)!=0)
59 { i0
=0xbff0000000000000l
;}
61 uint64_t i
= (0x000fffffffffffffl
)>>j0
;
62 if((i0
&i
)==0) return x
; /* x is integral */
63 math_force_eval(huge
+x
); /* raise inexact flag */
64 if(i0
<0) i0
+= (0x0010000000000000l
)>>j0
;
69 return x
+x
; /* inf or NaN */
73 weak_alias (__floor
, floor
)
74 # ifdef NO_LONG_DOUBLE
75 strong_alias (__floor
, __floorl
)
76 weak_alias (__floor
, floorl
)