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Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_nexttoward.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_nexttoward.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_nexttoward.c b/sysdeps/ieee754/ldbl-128/s_nexttoward.c
new file mode 100644
index 0000000000..f121be2fac
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/s_nexttoward.c
@@ -0,0 +1,97 @@
+/* s_nexttoward.c
+ * Conversion from s_nextafter.c by Ulrich Drepper, Cygnus Support,
+ * drepper@cygnus.com and Jakub Jelinek, jj@ultra.linux.cz.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: $";
+#endif
+
+/* IEEE functions
+ *	nexttoward(x,y)
+ *	return the next machine floating-point number of x in the
+ *	direction toward y.
+ *   Special cases:
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+	double __nexttoward(double x, long double y)
+#else
+	double __nexttoward(x,y)
+	double x;
+	long double y;
+#endif
+{
+	int32_t hx,ix;
+	int64_t hy,iy;
+	u_int32_t lx;
+	u_int64_t ly;
+
+	EXTRACT_WORDS(hx,lx,x);
+	GET_LDOUBLE_WORDS64(hy,ly,y);
+	ix = hx&0x7fffffff;		/* |x| */
+	iy = hy&0x7fffffffffffffffLL;	/* |y| */
+
+	if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) ||   /* x is nan */
+	   ((iy>=0x7fff000000000000LL)&&((iy-0x7fff000000000000LL)|ly)!=0))
+	   						    /* y is nan */
+	   return x+y;
+	if((long double) x==y) return x;	/* x=y, return x */
+	if((ix|lx)==0) {			/* x == 0 */
+	    double x2;
+	    INSERT_WORDS(x,(u_int32_t)((hy>>32)&0x80000000),1);/* return +-minsub */
+	    x2 = x*x;
+	    if(x2==x) return x2; else return x;	/* raise underflow flag */
+	}
+	if(hx>=0) {				/* x > 0 */
+	    if (hy<0||(ix>>20)>(iy>>48)-0x3c00
+		|| ((ix>>20)==(iy>>48)-0x3c00
+		    && (((((int64_t)hx)<<28)|(lx>>4))>(hy&0x0000ffffffffffffLL)
+			|| (((((int64_t)hx)<<28)|(lx>>4))==(hy&0x0000ffffffffffffLL)
+			    && (lx&0xf)>(ly>>60))))) {	/* x > y, x -= ulp */
+		if(lx==0) hx -= 1;
+		lx -= 1;
+	    } else {				/* x < y, x += ulp */
+		lx += 1;
+		if(lx==0) hx += 1;
+	    }
+	} else {				/* x < 0 */
+	    if (hy>=0||(ix>>20)>(iy>>48)-0x3c00
+		|| ((ix>>20)==(iy>>48)-0x3c00
+		    && (((((int64_t)hx)<<28)|(lx>>4))>(hy&0x0000ffffffffffffLL)
+			|| (((((int64_t)hx)<<28)|(lx>>4))==(hy&0x0000ffffffffffffLL)
+			    && (lx&0xf)>(ly>>60))))) {	/* x < y, x -= ulp */
+		if(lx==0) hx -= 1;
+		lx -= 1;
+	    } else {				/* x > y, x += ulp */
+		lx += 1;
+		if(lx==0) hx += 1;
+	    }
+	}
+	hy = hx&0x7ff00000;
+	if(hy>=0x7ff00000) return x+x;	/* overflow  */
+	if(hy<0x00100000) {		/* underflow */
+	    double x2 = x*x;
+	    if(x2!=x) {		/* raise underflow flag */
+	        INSERT_WORDS(x2,hx,lx);
+		return x2;
+	    }
+	}
+	INSERT_WORDS(x,hx,lx);
+	return x;
+}
+weak_alias (__nexttoward, nexttoward)