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-rw-r--r--src/math/s_nextafterf.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/src/math/s_nextafterf.c b/src/math/s_nextafterf.c
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+++ b/src/math/s_nextafterf.c
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+/* 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.
+ * ====================================================
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+float
+nextafterf(float x, float y)
+{
+ volatile float t;
+ 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 y; /* x=y, return y */
+ if(ix==0) { /* x == 0 */
+ SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */
+ t = x*x;
+ if(t==x) return t; 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 */
+ t = x*x;
+ if(t!=x) { /* raise underflow flag */
+ SET_FLOAT_WORD(y,hx);
+ return y;
+ }
+ }
+ SET_FLOAT_WORD(x,hx);
+ return x;
+}