initial import

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diff --git a/sysdeps/generic/fmod.c b/sysdeps/generic/fmod.c
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+/*
+ * Copyright (c) 1989, 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)fmod.c	8.1 (Berkeley) 6/4/93";
+#endif /* not lint */
+
+/* fmod.c
+ *
+ * SYNOPSIS
+ *
+ *    #include <math.h>
+ *    double fmod(double x, double y)
+ *
+ * DESCRIPTION
+ *
+ *    The fmod function computes the floating-point remainder of x/y.
+ *
+ * RETURNS
+ *
+ *    The fmod function returns the value x-i*y, for some integer i
+ * such that, if y is nonzero, the result has the same sign as x and
+ * magnitude less than the magnitude of y.
+ *
+ * On a VAX or CCI,
+ *
+ *    fmod(x,0) traps/faults on floating-point divided-by-zero.
+ *
+ * On IEEE-754 conforming machines with "isnan()" primitive,
+ *
+ *    fmod(x,0), fmod(INF,y) are invalid operations and NaN is returned.
+ *
+ */
+#if !defined(vax) && !defined(tahoe)
+extern int isnan(),finite();
+#endif	/* !defined(vax) && !defined(tahoe) */
+extern double frexp(),ldexp(),fabs();
+
+#ifdef TEST_FMOD
+static double
+_fmod(x,y)
+#else	/* TEST_FMOD */
+double
+fmod(x,y)
+#endif	/* TEST_FMOD */
+double x,y;
+{
+	int ir,iy;
+	double r,w;
+
+	if (y == (double)0
+#if !defined(vax) && !defined(tahoe)	/* per "fmod" manual entry, SunOS 4.0 */
+		|| isnan(y) || !finite(x)
+#endif	/* !defined(vax) && !defined(tahoe) */
+	    )
+	    return (x*y)/(x*y);
+
+	r = fabs(x);
+	y = fabs(y);
+	(void)frexp(y,&iy);
+	while (r >= y) {
+		(void)frexp(r,&ir);
+		w = ldexp(y,ir-iy);
+		r -= w <= r ? w : w*(double)0.5;
+	}
+	return x >= (double)0 ? r : -r;
+}
+
+#ifdef TEST_FMOD
+extern long random();
+extern double fmod();
+
+#define	NTEST	10000
+#define	NCASES	3
+
+static int nfail = 0;
+
+static void
+doit(x,y)
+double x,y;
+{
+	double ro = fmod(x,y),rn = _fmod(x,y);
+	if (ro != rn) {
+		(void)printf(" x    = 0x%08.8x %08.8x (%24.16e)\n",x,x);
+		(void)printf(" y    = 0x%08.8x %08.8x (%24.16e)\n",y,y);
+		(void)printf(" fmod = 0x%08.8x %08.8x (%24.16e)\n",ro,ro);
+		(void)printf("_fmod = 0x%08.8x %08.8x (%24.16e)\n",rn,rn);
+		(void)printf("\n");
+	}
+}
+
+main()
+{
+	register int i,cases;
+	double x,y;
+
+	srandom(12345);
+	for (i = 0; i < NTEST; i++) {
+		x = (double)random();
+		y = (double)random();
+		for (cases = 0; cases < NCASES; cases++) {
+			switch (cases) {
+			case 0:
+				break;
+			case 1:
+				y = (double)1/y; break;
+			case 2:
+				x = (double)1/x; break;
+			default:
+				abort(); break;
+			}
+			doit(x,y);
+			doit(x,-y);
+			doit(-x,y);
+			doit(-x,-y);
+		}
+	}
+	if (nfail)
+		(void)printf("Number of failures: %d (out of a total of %d)\n",
+			nfail,NTEST*NCASES*4);
+	else
+		(void)printf("No discrepancies were found\n");
+	exit(0);
+}
+#endif	/* TEST_FMOD */