1 files changed, 73 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/C/rint.c b/usr/src/lib/libm/common/C/rint.c
new file mode 100644
index 0000000000..f272969286
--- /dev/null
+++ b/usr/src/lib/libm/common/C/rint.c
@@ -0,0 +1,73 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
+ */
+/*
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma weak rint = __rint
+
+/*
+ * rint(x) return x rounded to integral according to the rounding direction
+ * rint(x) returns result with the same sign as x's,  including 0.0.
+ */
+
+#include "libm.h"
+
+#if defined(__i386) && !defined(__amd64) && (!defined(__FLT_EVAL_METHOD__) || \
+	__FLT_EVAL_METHOD__ != 0)
+extern enum fp_precision_type __swapRP(enum fp_precision_type);
+#define	DECLRP(x)	enum fp_precision_type x;
+#define	SWAPRP(new, x)	x = __swapRP(new);
+#define	RESTRP(x)	(void) __swapRP(x);
+#else
+#define	DECLRP(x)
+#define	SWAPRP(new, x)
+#define	RESTRP(x)
+#endif
+
+static const double
+	two52 = 4503599627370496.0,
+	zero = 0.0,
+	one = 1.0;
+
+double
+rint(double x) {
+	DECLRP(rp)
+	double	t, w;
+	int	ix, hx;
+
+	ix = ((int *)&x)[HIWORD];
+	hx = ix & ~0x80000000;
+
+	if (hx >= 0x43300000)
+		return (x * one);
+	t = (ix < 0)? -two52 : two52;
+	SWAPRP(fp_double, rp)		/* set precision mode to double */
+	w = x + t;			/* x+sign(x)*2**52 rounded */
+	RESTRP(rp)			/* restore precision mode */
+	if (w == t)
+		return ((ix < 0)? -zero : zero);
+	return (w - t);
+}