1  //    Copyright 2006-2010 Various Authors
  2  //
  3  //    This program is free software; you can redistribute it and/or modify
  4  //    it under the terms of the GNU General Public License as published by
  5  //    the Free Software Foundation; either version 2 of the License, or
  6  //    (at your option) any later version.
  7  //
  8  //    This program is distributed in the hope that it will be useful,
  9  //    but WITHOUT ANY WARRANTY; without even the implied warranty of
 10  //    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 11  //    GNU General Public License for more details.
 12  //
 13  //    You should have received a copy of the GNU General Public License
 14  //    along with this program; if not, write to the Free Software
 15  //    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 16  #ifndef RTAPI_MATH_H
 17  #define RTAPI_MATH_H
 18  
 19  #include "rtapi.h"  /* Because of all the rtapi refs */
 20  #include <float.h>  /* DBL_MAX and other FP goodies */
 21  
 22  #ifndef M_PIl
 23  #define M_PIl		3.1415926535897932384626433832795029L  /* pi */
 24  #endif
 25  #ifndef M_PI_2l
 26  #define M_PI_2l        1.570796326794896619231321691639751442L /* pi/2 */
 27  #endif
 28  #ifndef M_PI
 29  #define M_PI		3.1415926535897932384626433832795029   /* pi */
 30  #endif
 31  
 32  #if defined(__KERNEL__)
 33  extern double sin(double);
 34  extern double cos(double);
 35  extern double tan(double);
 36  extern double sqrt(double);
 37  extern double fabs(double);
 38  extern double atan(double);
 39  extern double atan2(double, double);
 40  extern double asin(double);
 41  extern double acos(double);
 42  extern double exp(double);
 43  extern double pow(double, double);
 44  extern double fmin(double, double);
 45  extern double fmax(double, double);
 46  extern double fmod(double, double);
 47  
 48  extern double round(double);
 49  extern double ceil(double);
 50  extern double floor(double);
 51  
 52  #define frexp(p,q) __builtin_frexp((p),(q))
 53  #define isnan(x) __builtin_isnan((x))
 54  #define signbit(x) __builtin_signbit((x))
 55  #define nan(x) __builtin_nan((x))
 56  
 57  #define isinf(x) __builtin_isinf((x))
 58  #define isfinite(x) __builtin_isfinite((x))
 59  
 60  extern __inline double atan (double __y) {
 61      return atan2(__y, 1.);
 62  }
 63  
 64  extern __inline double asin (double __x) {
 65      return atan2(__x, sqrt (1.0 - __x * __x));
 66  }
 67  
 68  extern __inline double acos (double __x) {
 69      return atan2(sqrt(1.0 - __x * __x), __x);
 70  }
 71  
 72  extern __inline double fmax(double __y, double __x) {
 73      return __y > __x || __builtin_isnan(__x) ? __y : __x;
 74  }
 75  extern __inline double fmin(double __y, double __x) {
 76      return __y < __x || __builtin_isnan(__x) ? __y : __x;
 77  }
 78  
 79  #ifdef __i386__
 80  #include "rtapi_math_i386.h"
 81  #endif
 82  
 83  #else
 84  #include <math.h>
 85  #endif
 86  
 87  #include "rtapi_byteorder.h"
 88  
 89  // adapted from ieee754.h
 90  union ieee754_double
 91    {
 92      double d;
 93  
 94      /* This is the IEEE 754 double-precision format.  */
 95      struct
 96        {
 97  #if     RTAPI_BIG_ENDIAN
 98          unsigned int negative:1;
 99          unsigned int exponent:11;
100          /* Together these comprise the mantissa.  */
101          unsigned int mantissa0:20;
102          unsigned int mantissa1:32;
103  #endif                          /* Big endian.  */
104  #if     RTAPI_LITTLE_ENDIAN
105  # if    RTAPI_FLOAT_BIG_ENDIAN
106          unsigned int mantissa0:20;
107          unsigned int exponent:11;
108          unsigned int negative:1;
109          unsigned int mantissa1:32;
110  # else
111          /* Together these comprise the mantissa.  */
112          unsigned int mantissa1:32;
113          unsigned int mantissa0:20;
114          unsigned int exponent:11;
115          unsigned int negative:1;
116  # endif
117  #endif                          /* Little endian.  */
118        } ieee;
119  
120      /* This format makes it easier to see if a NaN is a signalling NaN.  */
121      struct
122        {
123  #if     RTAPI_BIG_ENDIAN
124          unsigned int negative:1;
125          unsigned int exponent:11;
126          unsigned int quiet_nan:1;
127          /* Together these comprise the mantissa.  */
128          unsigned int mantissa0:19;
129          unsigned int mantissa1:32;
130  #else
131  # if    RTAPI_FLOAT_BIG_ENDIAN
132          unsigned int mantissa0:19;
133          unsigned int quiet_nan:1;
134          unsigned int exponent:11;
135          unsigned int negative:1;
136          unsigned int mantissa1:32;
137  # else
138          /* Together these comprise the mantissa.  */
139          unsigned int mantissa1:32;
140          unsigned int mantissa0:19;
141          unsigned int quiet_nan:1;
142          unsigned int exponent:11;
143          unsigned int negative:1;
144  # endif
145  #endif
146        } ieee_nan;
147    };
148  
149  #define IEEE754_DOUBLE_BIAS     0x3ff /* Added to exponent.  */
150  
151  #endif