1/****************************************************************
  2
  3The author of this software is David M. Gay.
  4
  5Copyright (C) 2005 by David M. Gay
  6All Rights Reserved
  7
  8Permission to use, copy, modify, and distribute this software and its
  9documentation for any purpose and without fee is hereby granted,
 10provided that the above copyright notice appear in all copies and that
 11both that the copyright notice and this permission notice and warranty
 12disclaimer appear in supporting documentation, and that the name of
 13the author or any of his current or former employers not be used in
 14advertising or publicity pertaining to distribution of the software
 15without specific, written prior permission.
 16
 17THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 18INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN
 19NO EVENT SHALL THE AUTHOR OR ANY OF HIS CURRENT OR FORMER EMPLOYERS BE
 20LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
 21DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 22WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
 23ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 24SOFTWARE.
 25
 26****************************************************************/
 27
 28/* Please send bug reports to David M. Gay (dmg at acm dot org,
 29 * with " at " changed at "@" and " dot " changed to ".").	*/
 30
 31/* Program to compute quiet NaNs of various precisions (float,	*/
 32/* double, and perhaps long double) on the current system,	*/
 33/* provided the system uses binary IEEE (P754) arithmetic.	*/
 34/* Note that one system's quiet NaN may be a signaling NaN on	*/
 35/* another system.  The IEEE arithmetic standards (P754, P854)	*/
 36/* do not specify how to distinguish signaling NaNs from quiet	*/
 37/* ones, and this detail varies across systems.	 The computed	*/
 38/* NaN values are encoded in #defines for values for an		*/
 39/* unsigned 32-bit integer type, called Ulong below, and	*/
 40/* (for long double) perhaps as unsigned short values.  Once	*/
 41/* upon a time, there were PC compilers for Intel CPUs that	*/
 42/* had sizeof(long double) = 10.  Are such compilers still	*/
 43/* distributed?							*/
 44
 45#include <stdio.h>
 46#include "gd_arith.h"
 47
 48#ifndef Long
 49#define Long long
 50#endif
 51
 52typedef unsigned Long Ulong;
 53
 54#ifdef NO_LONG_LONG
 55#undef Gen_ld_QNAN
 56#endif
 57
 58#undef HAVE_IEEE
 59#ifdef IEEE_8087
 60#define _0 1
 61#define _1 0
 62#ifdef Gen_ld_QNAN
 63#define _3 3
 64static int perm[4] = { 0, 1, 2, 3 };
 65#endif
 66#define HAVE_IEEE
 67#endif
 68#ifdef IEEE_MC68k
 69#define _0 0
 70#define _1 1
 71#ifdef Gen_ld_QNAN
 72#define _3 0
 73static int perm[4] = { 3, 2, 1, 0 };
 74#endif
 75#define HAVE_IEEE
 76#endif
 77
 78#define UL (unsigned long)
 79
 80#ifdef MINGW_BUILD_GEN
 81 int
 82main(void)
 83{
 84#ifdef HAVE_IEEE
 85	typedef union {
 86		float f;
 87		double d;
 88		Ulong L[4];
 89#ifndef NO_LONG_LONG
 90		unsigned short u[5];
 91		long double D;
 92#endif
 93		} U;
 94	U a, b, c;
 95#ifdef Gen_ld_QNAN
 96	int i;
 97#endif
 98
 99	a.L[0] = b.L[0] = 0x7f800000;
100	c.f = a.f - b.f;
101	printf("#define f_QNAN 0x%lx\n", UL (c.L[0] & 0x7fffffff));
102	a.L[_0] = b.L[_0] = 0x7ff00000;
103	a.L[_1] = b.L[_1] = 0;
104	c.d = a.d - b.d;	/* quiet NaN */
105	c.L[_0] &= 0x7fffffff;
106	printf("#define d_QNAN0 0x%lx\n", UL c.L[0]);
107	printf("#define d_QNAN1 0x%lx\n", UL c.L[1]);
108#ifdef Gen_ld_QNAN
109	if (sizeof(a.D) >= 16) {
110		b.D = c.D = a.d;
111		if (printf("") < 0)
112			c.D = 37;	/* never executed; just defeat optimization */
113		a.L[0] = a.L[1] = a.L[2] = a.L[3] = 0;
114		a.D = b.D - c.D;
115		a.L[_3] &= 0x7fffffff;
116		for(i = 0; i < 4; i++)
117			printf("#define ld_QNAN%d 0x%lx\n", i, UL a.L[perm[i]]);
118		}
119#endif
120#endif /* HAVE_IEEE */
121	return 0;
122	}
123#endif