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-rw-r--r--sysdeps/libm-ieee754/s_rintf.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_rintf.c b/sysdeps/libm-ieee754/s_rintf.c
new file mode 100644
index 0000000000..4e5b409b29
--- /dev/null
+++ b/sysdeps/libm-ieee754/s_rintf.c
@@ -0,0 +1,72 @@
+/* s_rintf.c -- float version of s_rint.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_rintf.c,v 1.4 1995/05/10 20:48:06 jtc Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const float
+#else
+static float 
+#endif
+TWO23[2]={
+  8.3886080000e+06, /* 0x4b000000 */
+ -8.3886080000e+06, /* 0xcb000000 */
+};
+
+#ifdef __STDC__
+	float __rintf(float x)
+#else
+	float __rintf(x)
+	float x;
+#endif
+{
+	int32_t i0,j0,sx;
+	u_int32_t i,i1;
+	float w,t;
+	GET_FLOAT_WORD(i0,x);
+	sx = (i0>>31)&1;
+	j0 = ((i0>>23)&0xff)-0x7f;
+	if(j0<23) {
+	    if(j0<0) { 	
+		if((i0&0x7fffffff)==0) return x;
+		i1 = (i0&0x07fffff);
+		i0 &= 0xfff00000;
+		i0 |= ((i1|-i1)>>9)&0x400000;
+		SET_FLOAT_WORD(x,i0);
+	        w = TWO23[sx]+x;
+	        t =  w-TWO23[sx];
+		GET_FLOAT_WORD(i0,t);
+		SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
+	        return t;
+	    } else {
+		i = (0x007fffff)>>j0;
+		if((i0&i)==0) return x; /* x is integral */
+		i>>=1;
+		if((i0&i)!=0) i0 = (i0&(~i))|((0x100000)>>j0);
+	    }
+	} else {
+	    if(j0==0x80) return x+x;	/* inf or NaN */
+	    else return x;		/* x is integral */
+	}
+	SET_FLOAT_WORD(x,i0);
+	w = TWO23[sx]+x;
+	return w-TWO23[sx];
+}
+weak_alias (__rintf, rintf)