96 bit long double nextafterl implementation. See sysdeps/libm-ieee754/s_nextafterl...
authordrepper <drepper>
Wed, 14 Jul 1999 00:14:34 +0000 (00:14 +0000)
committerdrepper <drepper>
Wed, 14 Jul 1999 00:14:34 +0000 (00:14 +0000)
sysdeps/ieee754/ldbl-96/s_nextafterl.c [new file with mode: 0644]

diff --git a/sysdeps/ieee754/ldbl-96/s_nextafterl.c b/sysdeps/ieee754/ldbl-96/s_nextafterl.c
new file mode 100644 (file)
index 0000000..aea57e3
--- /dev/null
@@ -0,0 +1,101 @@
+/* s_nextafterl.c -- long double version of s_nextafter.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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"
+
+#ifdef __STDC__
+       long double __nextafterl(long double x, long double y)
+#else
+       long double __nextafterl(x,y)
+       long double x,y;
+#endif
+{
+       int32_t hx,hy,ix,iy;
+       u_int32_t lx,ly,esx,esy;
+
+       GET_LDOUBLE_WORDS(esx,hx,lx,x);
+       GET_LDOUBLE_WORDS(esy,hy,ly,y);
+       ix = esx&0x7fff;                /* |x| */
+       iy = esy&0x7fff;                /* |y| */
+
+       if(((ix==0x7fff)&&((hx|lx)|-(hx|lx))!=0) ||   /* x is nan */
+          ((iy==0x7fff)&&((hy|ly)|-(hy|ly))!=0))     /* y is nan */
+          return x+y;
+       if(x==y) return y;              /* x=y, return y */
+       if((ix|hx|lx)==0) {                     /* x == 0 */
+           SET_LDOUBLE_WORDS(x,esx&0x8000,0,1);/* return +-minsubnormal */
+           y = x*x;
+           if(y==x) return y; else return x;   /* raise underflow flag */
+       }
+       if(esx<0x8000) {                        /* x > 0 */
+           if(ix>iy||((ix==iy) && (hx>hy||((hx==hy)&&(lx>ly))))) {
+             /* x > y, x -= ulp */
+               if(lx==0) {
+                   if (hx==0) esx -= 1;
+                   hx -= 1;
+               }
+               lx -= 1;
+           } else {                            /* x < y, x += ulp */
+               lx += 1;
+               if(lx==0) {
+                   hx += 1;
+                   if (hx==0)
+                       esx += 1;
+               }
+           }
+       } else {                                /* x < 0 */
+           if(esy>=0||(ix>iy||((ix==iy)&&(hx>hy||((hx==hy)&&(lx>ly)))))){
+             /* x < y, x -= ulp */
+               if(lx==0) {
+                   if (hx==0) esx -= 1;
+                   hx -= 1;
+               }
+               lx -= 1;
+           } else {                            /* x > y, x += ulp */
+               lx += 1;
+               if(lx==0) {
+                   hx += 1;
+                   if (hx==0) esx += 1;
+               }
+           }
+       }
+       esy = esx&0x7fff;
+       if(esy==0x7fff) return x+x;     /* overflow  */
+       if(esy==0) {                    /* underflow */
+           y = x*x;
+           if(y!=x) {          /* raise underflow flag */
+               SET_LDOUBLE_WORDS(y,esx,hx,lx);
+               return y;
+           }
+       }
+       SET_LDOUBLE_WORDS(x,esx,hx,lx);
+       return x;
+}
+weak_alias (__nextafterl, nextafterl)
+strong_alias (__nextafterl, __nexttowardl)
+weak_alias (__nextafterl, nexttowardl)