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 (at) 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
