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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c b/sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c
new file mode 100644
index 0000000000..e35ce50829
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c
@@ -0,0 +1,108 @@
+/* s_nextafterl.c -- long double version of s_nextafter.c.
+ * Conversion to IEEE quad long double by 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
+ *	nextafterl(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"
+#include <math_ldbl_opt.h>
+
+#ifdef __STDC__
+	long double __nextafterl(long double x, long double y)
+#else
+	long double __nextafterl(x,y)
+	long double x,y;
+#endif
+{
+	int64_t hx,hy,ihx,ihy,ilx,ily;
+	u_int64_t lx,ly;
+
+	GET_LDOUBLE_WORDS64(hx,lx,x);
+	GET_LDOUBLE_WORDS64(hy,ly,y);
+	ihx = hx&0x7fffffffffffffffLL;		/* |hx| */
+	ilx = lx&0x7fffffffffffffffLL;		/* |lx| */
+	ihy = hy&0x7fffffffffffffffLL;		/* |hy| */
+	ily = ly&0x7fffffffffffffffLL;		/* |ly| */
+
+	if((((ihx&0x7ff0000000000000LL)==0x7ff0000000000000LL)&&
+	    ((ihx&0x000fffffffffffffLL)!=0)) ||   /* x is nan */
+	   (((ihy&0x7ff0000000000000LL)==0x7ff0000000000000LL)&&
+	    ((ihy&0x000fffffffffffffLL)!=0)))     /* y is nan */
+	    return x+y; /* signal the nan */
+	if(x==y)
+	    return y;		/* x=y, return y */
+	if(ihx == 0 && ilx == 0) {			/* x == 0 */
+	    SET_LDOUBLE_WORDS64(x,hy&0x8000000000000000ULL,1);/* return +-minsubnormal */
+	    y = x*x;
+	    if(y==x) return y; else return x;	/* raise underflow flag */
+	}
+	if(ihx>=0) {			/* x > 0 */
+	    if(ihx>ihy||((ihx==ihy)&&(ilx>ily))) {	/* x > y, x -= ulp */
+
+	        if(ilx==0)
+		    hx--;
+		else
+		    lx--;
+	    } else {				/* x < y, x += ulp */
+	        if((hx==0x7fefffffffffffffLL)&&(lx==0x7c8ffffffffffffeLL))
+		  {
+		    SET_LDOUBLE_WORDS64(x,0x7ff0000000000000,0x8000000000000000);
+		    return x;
+		  }
+	        else if((hx==0xffefffffffffffffLL)&&(lx==0xfc8ffffffffffffeLL))
+		  {
+		    SET_LDOUBLE_WORDS64(x,0xfff0000000000000,0x8000000000000000);
+		    return x;
+		  }
+		else if((lx&0x7fffffffffffffff)==0) hx++;
+		else
+		  lx++;
+	    }
+	} else {				/* x < 0 */
+	    if(ihy>=0||ihx>ihy||((ihx==ihy)&&(ilx>ily))){/* x < y, x -= ulp */
+		if((lx&0x7fffffffffffffff)==0)
+		    hx--;
+		else
+		    lx--;
+	    } else {				/* x > y, x += ulp */
+		if((lx&0x7fffffffffffffff)==0) hx++;
+		else
+		  lx++;
+	    }
+	}
+	hy = hx&0x7ff0000000000000LL;
+	if(hy==0x7ff0000000000000LL) return x+x;/* overflow  */
+	if(hy==0) {				/* underflow */
+	    y = x*x;
+	    if(y!=x) {		/* raise underflow flag */
+	        SET_LDOUBLE_WORDS64(y,hx,lx);
+		return y;
+	    }
+	}
+	SET_LDOUBLE_WORDS64(x,hx,lx);
+	return x;
+}
+strong_alias (__nextafterl, __nexttowardl)
+long_double_symbol (libm, __nextafterl, nextafterl);
+long_double_symbol (libm, __nexttowardl, nexttowardl);