/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice 
 * is preserved.
 * ====================================================
 */

/*
 * from: @(#)fdlibm.h 5.1 93/09/24
 * $Id: mathP.h,v 1.5 2008/12/10 14:41:12 ando Exp $
 */

#ifndef _MATH_PRIVATE_H_
#define _MATH_PRIVATE_H_

#ifdef MODULE
#include <linux/types.h>
#else
#include <sys/types.h>
#endif
#include "rtapi_byteorder.h"

#define __P(args) args

/* Support for various different standard error handling behaviors.  */
typedef enum
{
  _IEEE_ = -1,  /* According to IEEE 754/IEEE 854.  */
  _SVID_,       /* According to System V, release 4.  */
  _XOPEN_,      /* Nowadays also Unix98.  */
  _POSIX_,
  _ISOC_        /* Actually this is ISO C99.  */
} _LIB_VERSION_TYPE;

/* Types of exceptions in the `type' field.  */
# define DOMAIN		1
# define SING		2
# define OVERFLOW	3
# define UNDERFLOW	4
# define TLOSS		5
# define PLOSS		6
/* SVID mode specifies returning this large value instead of infinity.  */
# define HUGE		3.40282347e+38F

// fake SVID exception structure - see k_standard.c
struct exception  {
    int type;
    char *name;
    double arg1;
    double arg2;
    double retval;
  };
#define matherr(arg) (0)

/* This variable can be changed at run-time to any of the values above to
   affect floating point error handling behavior (it may also be necessary
   to change the hardware FPU exception settings).  */
extern _LIB_VERSION_TYPE _LIB_VERSION;

extern double __kernel_standard(double x, double y, int type);

/* The original fdlibm code used statements like:
	n0 = ((*(int*)&one)>>29)^1;		* index of high word *
	ix0 = *(n0+(int*)&x);			* high word of x *
	ix1 = *((1-n0)+(int*)&x);		* low word of x *
   to dig two 32 bit words out of the 64 bit IEEE floating point
   value.  That is non-ANSI, and, moreover, the gcc instruction
   scheduler gets it wrong.  We instead use the following macros.
   Unlike the original code, we determine the endianness at compile
   time, not at run time; I don't see much benefit to selecting
   endianness at run time.  */

/* A union which permits us to convert between a double and two 32 bit
   ints.  */

/*
 * Math on arm is little endian except for the FP word order which is
 * big endian.
 */

#if ( RTAPI_BIG_ENDIAN ) && ( RTAPI_LITTLE_ENDIAN )
#error "Cannot have both Big and Little Endian"
#endif

#if RTAPI_BIG_ENDIAN

typedef union 
{
  double value;
  struct 
  {
    u_int32_t msw;
    u_int32_t lsw;
  } parts;
} ieee_double_shape_type;

#endif

#if RTAPI_LITTLE_ENDIAN

typedef union 
{
  double value;
  struct 
  {
    u_int32_t lsw;
    u_int32_t msw;
  } parts;
} ieee_double_shape_type;

#endif

/* Get two 32 bit ints from a double.  */

#define EXTRACT_WORDS(ix0,ix1,d)				\
do {								\
  ieee_double_shape_type ew_u;					\
  ew_u.value = (d);						\
  (ix0) = ew_u.parts.msw;					\
  (ix1) = ew_u.parts.lsw;					\
} while (0)

/* Get the more significant 32 bit int from a double.  */

#define GET_HIGH_WORD(i,d)					\
do {								\
  ieee_double_shape_type gh_u;					\
  gh_u.value = (d);						\
  (i) = gh_u.parts.msw;						\
} while (0)

/* Get the less significant 32 bit int from a double.  */

#define GET_LOW_WORD(i,d)					\
do {								\
  ieee_double_shape_type gl_u;					\
  gl_u.value = (d);						\
  (i) = gl_u.parts.lsw;						\
} while (0)

/* Set a double from two 32 bit ints.  */

#define INSERT_WORDS(d,ix0,ix1)					\
do {								\
  ieee_double_shape_type iw_u;					\
  iw_u.parts.msw = (ix0);					\
  iw_u.parts.lsw = (ix1);					\
  (d) = iw_u.value;						\
} while (0)

/* Set the more significant 32 bits of a double from an int.  */

#define SET_HIGH_WORD(d,v)					\
do {								\
  ieee_double_shape_type sh_u;					\
  sh_u.value = (d);						\
  sh_u.parts.msw = (v);						\
  (d) = sh_u.value;						\
} while (0)

/* Set the less significant 32 bits of a double from an int.  */

#define SET_LOW_WORD(d,v)					\
do {								\
  ieee_double_shape_type sl_u;					\
  sl_u.value = (d);						\
  sl_u.parts.lsw = (v);						\
  (d) = sl_u.value;						\
} while (0)

/* A union which permits us to convert between a float and a 32 bit
   int.  */

typedef union
{
  float value;
  u_int32_t word;
} ieee_float_shape_type;

/* Get a 32 bit int from a float.  */

#define GET_FLOAT_WORD(i,d)					\
do {								\
  ieee_float_shape_type gf_u;					\
  gf_u.value = (d);						\
  (i) = gf_u.word;						\
} while (0)

/* Set a float from a 32 bit int.  */

#define SET_FLOAT_WORD(d,i)					\
do {								\
  ieee_float_shape_type sf_u;					\
  sf_u.word = (i);						\
  (d) = sf_u.value;						\
} while (0)

/* ieee style elementary functions */
extern double __ieee754_sqrt __P((double));			
extern double __ieee754_acos __P((double));			
extern double __ieee754_acosh __P((double));			
extern double __ieee754_log __P((double));			
extern double __ieee754_atanh __P((double));			
extern double __ieee754_asin __P((double));			
extern double __ieee754_atan2 __P((double,double));			
extern double __ieee754_exp __P((double));
extern double __ieee754_cosh __P((double));
extern double __ieee754_fmod __P((double,double));
extern double __ieee754_pow __P((double,double));
extern double __ieee754_lgamma_r __P((double,int *));
extern double __ieee754_gamma_r __P((double,int *));
extern double __ieee754_lgamma __P((double));
extern double __ieee754_gamma __P((double));
extern double __ieee754_log10 __P((double));
extern double __ieee754_sinh __P((double));
extern double __ieee754_hypot __P((double,double));
extern double __ieee754_j0 __P((double));
extern double __ieee754_j1 __P((double));
extern double __ieee754_y0 __P((double));
extern double __ieee754_y1 __P((double));
extern double __ieee754_jn __P((int,double));
extern double __ieee754_yn __P((int,double));
extern double __ieee754_remainder __P((double,double));
extern int    __ieee754_rem_pio2 __P((double,double*));
#if defined(_SCALB_INT)
extern double __ieee754_scalb __P((double,int));
#else
extern double __ieee754_scalb __P((double,double));
#endif

/* fdlibm kernel function */
extern double __kernel_standard __P((double,double,int));	
extern double __kernel_sin __P((double,double,int));
extern double __kernel_cos __P((double,double));
extern double __kernel_tan __P((double,double,int));
extern int    __kernel_rem_pio2 __P((double*,double*,int,int,int,const int*));


/* ieee style elementary float functions */
extern float __ieee754_sqrtf __P((float));			
extern float __ieee754_acosf __P((float));			
extern float __ieee754_acoshf __P((float));			
extern float __ieee754_logf __P((float));			
extern float __ieee754_atanhf __P((float));			
extern float __ieee754_asinf __P((float));			
extern float __ieee754_atan2f __P((float,float));			
extern float __ieee754_expf __P((float));
extern float __ieee754_coshf __P((float));
extern float __ieee754_fmodf __P((float,float));
extern float __ieee754_powf __P((float,float));
extern float __ieee754_lgammaf_r __P((float,int *));
extern float __ieee754_gammaf_r __P((float,int *));
extern float __ieee754_lgammaf __P((float));
extern float __ieee754_gammaf __P((float));
extern float __ieee754_log10f __P((float));
extern float __ieee754_sinhf __P((float));
extern float __ieee754_hypotf __P((float,float));
extern float __ieee754_j0f __P((float));
extern float __ieee754_j1f __P((float));
extern float __ieee754_y0f __P((float));
extern float __ieee754_y1f __P((float));
extern float __ieee754_jnf __P((int,float));
extern float __ieee754_ynf __P((int,float));
extern float __ieee754_remainderf __P((float,float));
extern int   __ieee754_rem_pio2f __P((float,float*));
extern float __ieee754_scalbf __P((float,float));

/* float versions of fdlibm kernel functions */
extern float __kernel_sinf __P((float,float,int));
extern float __kernel_cosf __P((float,float));
extern float __kernel_tanf __P((float,float,int));
extern int   __kernel_rem_pio2f __P((float*,float*,int,int,int,const int*));

extern double __powidf2(double a, int b);
#endif /* _MATH_PRIVATE_H_ */
