lib/libm/common_source/mathimpl.h

   1 /*
   2  * Copyright (c) 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)mathimpl.h  8.1 (Berkeley) 6/4/93
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #include <math.h>
  38
  39 #if defined(vax)||defined(tahoe)
  40
  41 /* Deal with different ways to concatenate in cpp */
  42 #  ifdef __STDC__
  43 #    define     cat3(a,b,c) a ## b ## c
  44 #  else
  45 #    define     cat3(a,b,c) a/**/b/**/c
  46 #  endif
  47
  48 /* Deal with vax/tahoe byte order issues */
  49 #  ifdef vax
  50 #    define     cat3t(a,b,c) cat3(a,b,c)
  51 #  else
  52 #    define     cat3t(a,b,c) cat3(a,c,b)
  53 #  endif
  54
  55 #  define vccast(name) (*(const double *)(cat3(name,,x)))
  56
  57    /*
  58     * Define a constant to high precision on a Vax or Tahoe.
  59     *
  60     * Args are the name to define, the decimal floating point value,
  61     * four 16-bit chunks of the float value in hex
  62     * (because the vax and tahoe differ in float format!), the power
  63     * of 2 of the hex-float exponent, and the hex-float mantissa.
  64     * Most of these arguments are not used at compile time; they are
  65     * used in a post-check to make sure the constants were compiled
  66     * correctly.
  67     *
  68     * People who want to use the constant will have to do their own
  69     *     #define foo vccast(foo)
  70     * since CPP cannot do this for them from inside another macro (sigh).
  71     * We define "vccast" if this needs doing.
  72     */
  73 #  define vc(name, value, x1,x2,x3,x4, bexp, xval) \
  74         static long const cat3(name,,x)[] = {cat3t(0x,x1,x2), cat3t(0x,x3,x4)};
  75
  76 #  define ic(name, value, bexp, xval) ;
  77
  78 #else   /* vax or tahoe */
  79
  80    /* Hooray, we have an IEEE machine */
  81 #  undef vccast
  82 #  define vc(name, value, x1,x2,x3,x4, bexp, xval) ;
  83
  84 #  define ic(name, value, bexp, xval) \
  85         static double const name = value;
  86
  87 #endif  /* defined(vax)||defined(tahoe) */
  88
  89
  90 /*
  91  * Functions internal to the math package, yet not static.
  92  */
  93 extern double   __exp__E(double, double);
  94 extern double   __log__L(double);
  95
  96 struct Double {double a, b;};
  97 double __exp__D(double, double);
  98 struct Double __log__D(double);