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-rw-r--r--libm/src/s_nexttowardf.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/libm/src/s_nexttowardf.c b/libm/src/s_nexttowardf.c
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+++ b/libm/src/s_nexttowardf.c
@@ -0,0 +1,60 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#ifndef lint
+static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_nexttowardf.c,v 1.1 2005/03/07 04:57:38 das Exp $";
+#endif
+
+#include <float.h>
+
+#include "fpmath.h"
+#include "math.h"
+#include "math_private.h"
+
+#define LDBL_INFNAN_EXP (LDBL_MAX_EXP * 2 - 1)
+
+float
+nexttowardf(float x, long double y)
+{
+ union IEEEl2bits uy;
+ volatile float t;
+ int32_t hx,ix;
+
+ GET_FLOAT_WORD(hx,x);
+ ix = hx&0x7fffffff; /* |x| */
+ uy.e = y;
+
+ if((ix>0x7f800000) ||
+ (uy.bits.exp == LDBL_INFNAN_EXP &&
+ ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl) != 0))
+ return x+y; /* x or y is nan */
+ if(x==y) return (float)y; /* x=y, return y */
+ if(ix==0) { /* x == 0 */
+ SET_FLOAT_WORD(x,(uy.bits.sign<<31)|1);/* return +-minsubnormal */
+ t = x*x;
+ if(t==x) return t; else return x; /* raise underflow flag */
+ }
+ if(hx>=0 ^ x < y) /* x -= ulp */
+ hx -= 1;
+ else /* x += ulp */
+ hx += 1;
+ ix = hx&0x7f800000;
+ if(ix>=0x7f800000) return x+x; /* overflow */
+ if(ix<0x00800000) { /* underflow */
+ t = x*x;
+ if(t!=x) { /* raise underflow flag */
+ SET_FLOAT_WORD(y,hx);
+ return y;
+ }
+ }
+ SET_FLOAT_WORD(x,hx);
+ return x;
+}