/*      $NetBSD: mathimpl.h,v 1.11 2024/07/17 12:00:48 riastradh Exp $  */
/*
* Copyright (c) 1988, 1993
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*      @(#)mathimpl.h  8.1 (Berkeley) 6/4/93
*/
#ifndef _NOIEEE_SRC_MATHIMPL_H_
#define _NOIEEE_SRC_MATHIMPL_H_

#include <sys/cdefs.h>
#include <math.h>
#include <stdint.h>

#if defined(__vax__) || defined(tahoe)

/* Deal with different ways to concatenate in cpp */
#define cat3(a,b,c)     a ## b ## c

/* Deal with vax/tahoe byte order issues */
#  ifdef __vax__
#    define     cat3t(a,b,c) cat3(a,b,c)
#  else
#    define     cat3t(a,b,c) cat3(a,c,b)
#  endif

#  define vccast(name) (cat3(__,name,x).d)

  /*
   * Define a constant to high precision on a Vax or Tahoe.
   *
   * Args are the name to define, the decimal floating point value,
   * four 16-bit chunks of the float value in hex
   * (because the vax and tahoe differ in float format!), the power
   * of 2 of the hex-float exponent, and the hex-float significand.
   * Most of these arguments are not used at compile time; they are
   * used in a post-check to make sure the constants were compiled
   * correctly.
   *
   * People who want to use the constant will have to do their own
   *     #define foo vccast(foo)
   * since CPP cannot do this for them from inside another macro (sigh).
   * We define "vccast" if this needs doing.
   */
#ifdef _LIBM_DECLARE
#  define vc(name, value, x1,x2,x3,x4, bexp, xval) \
   const union { uint32_t l[2]; double d; } cat3(__,name,x) = { \
       .l = { [0] = cat3t(0x,x1,x2), [1] = cat3t(0x,x3,x4) } };
#elif defined(_LIBM_STATIC)
#  define vc(name, value, x1,x2,x3,x4, bexp, xval) \
   static const union { uint32_t l[2]; double d; } cat3(__,name,x) = { \
       .l = { [0] = cat3t(0x,x1,x2), [1] = cat3t(0x,x3,x4) } };
#else
#  define vc(name, value, x1,x2,x3,x4, bexp, xval) \
       extern const union { uint32_t l[2]; double d; } cat3(__,name,x);
#endif
#  define ic(name, value, bexp, xval)

#else   /* __vax__ or tahoe */

  /* Hooray, we have an IEEE machine */
#  undef vccast
#  define vc(name, value, x1,x2,x3,x4, bexp, xval)

#ifdef _LIBM_DECLARE
#  define ic(name, value, bexp, xval) \
       const double __CONCAT(__,name) = value;
#elif _LIBM_STATIC
#  define ic(name, value, bexp, xval) \
       static const double __CONCAT(__,name) = value;
#else
#  define ic(name, value, bexp, xval) \
       extern const double __CONCAT(__,name);
#endif

#endif  /* defined(__vax__)||defined(tahoe) */

#ifdef __vax__
#include <machine/float.h>
#define _TINY   DBL_EPSILON
#define _TINYER DBL_EPSILON
#define _HUGE   DBL_MAX
#else
#define _TINY   1e-300
#define _TINYER 1e-308
#define _HUGE   1e+300
#endif


/*
* Functions internal to the math package, yet not static.
*/
extern double   __exp__E(double, double);
extern double   __log__L(double);
extern int      infnan(int);

struct Double {double a, b;};
double __exp__D(double, double);
struct Double __log__D(double);

#endif /* _NOIEEE_SRC_MATHIMPL_H_ */