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-rw-r--r--sysdeps/libm-ieee754/s_nextafterf.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_nextafterf.c b/sysdeps/libm-ieee754/s_nextafterf.c
new file mode 100644
index 0000000000..bc8d04260f
--- /dev/null
+++ b/sysdeps/libm-ieee754/s_nextafterf.c
@@ -0,0 +1,71 @@
+/* s_nextafterf.c -- float version of s_nextafter.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@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: s_nextafterf.c,v 1.4 1995/05/10 20:48:01 jtc Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+	float __nextafterf(float x, float y)
+#else
+	float __nextafterf(x,y)
+	float x,y;
+#endif
+{
+	int32_t hx,hy,ix,iy;
+
+	GET_FLOAT_WORD(hx,x);
+	GET_FLOAT_WORD(hy,y);
+	ix = hx&0x7fffffff;		/* |x| */
+	iy = hy&0x7fffffff;		/* |y| */
+
+	if((ix>0x7f800000) ||   /* x is nan */ 
+	   (iy>0x7f800000))     /* y is nan */ 
+	   return x+y;				
+	if(x==y) return x;		/* x=y, return x */
+	if(ix==0) {				/* x == 0 */
+	    SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */
+	    y = x*x;
+	    if(y==x) return y; else return x;	/* raise underflow flag */
+	} 
+	if(hx>=0) {				/* x > 0 */
+	    if(hx>hy) {				/* x > y, x -= ulp */
+		hx -= 1;
+	    } else {				/* x < y, x += ulp */
+		hx += 1;
+	    }
+	} else {				/* x < 0 */
+	    if(hy>=0||hx>hy){			/* x < y, x -= ulp */
+		hx -= 1;
+	    } else {				/* x > y, x += ulp */
+		hx += 1;
+	    }
+	}
+	hy = hx&0x7f800000;
+	if(hy>=0x7f800000) return x+x;	/* overflow  */
+	if(hy<0x00800000) {		/* underflow */
+	    y = x*x;
+	    if(y!=x) {		/* raise underflow flag */
+	        SET_FLOAT_WORD(y,hx);
+		return y;
+	    }
+	}
+	SET_FLOAT_WORD(x,hx);
+	return x;
+}
+weak_alias (__nextafterf, nextafterf)