1 /* Inline math functions for x86-64.
2 Copyright (C) 2002, 2003, 2004, 2007, 2009 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Andreas Jaeger <aj@suse.de>, 2002.
5
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.
10
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.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA. */
20
21 #ifndef _MATH_H
22 # error "Never use <bits/mathinline.h> directly; include <math.h> instead."
23 #endif
24
25 #include <bits/wordsize.h>
26
27 #ifndef __extern_inline
28 # define __MATH_INLINE __inline
29 #else
30 # define __MATH_INLINE __extern_inline
31 #endif
32
33
34 #if defined __USE_ISOC99 && defined __GNUC__ && __GNUC__ >= 2
35
36 /* Test for negative number. Used in the signbit() macro. */
37 __MATH_INLINE int
38 __NTH (__signbitf (float __x))
39 {
40 #if __WORDSIZE == 32
41 __extension__ union { float __f; int __i; } __u = { __f: __x };
42 return __u.__i < 0;
43 #else
44 int __m;
45 __asm ("pmovmskb %1, %0" : "=r" (__m) : "x" (__x));
46 return __m & 0x8;
47 #endif
48 }
49 __MATH_INLINE int
50 __NTH (__signbit (double __x))
51 {
52 #if __WORDSIZE == 32
53 __extension__ union { double __d; int __i[2]; } __u = { __d: __x };
54 return __u.__i[1] < 0;
55 #else
56 int __m;
57 __asm ("pmovmskb %1, %0" : "=r" (__m) : "x" (__x));
58 return __m & 0x80;
59 #endif
60 }
61 __MATH_INLINE int
62 __NTH (__signbitl (long double __x))
63 {
64 __extension__ union { long double __l; int __i[3]; } __u = { __l: __x };
65 return (__u.__i[2] & 0x8000) != 0;
66 }
67 #endif
68