693 Opensource replacement of sunwlibm

Reviewed by: Igor Kozhukhov ikozhukhov@gmail.com
Reviewed by: Keith M Wesolowski <keith.wesolowski@joyent.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Approved by: Dan McDonald <danmcd@omniti.com>

1 files changed, 75 insertions, 0 deletions

diff --git a/usr/src/lib/libm/common/Q/rintl.c b/usr/src/lib/libm/common/Q/rintl.c
new file mode 100644
index 0000000000..a721e4231b
--- /dev/null
+++ b/usr/src/lib/libm/common/Q/rintl.c
@@ -0,0 +1,75 @@
+/*
+ * 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 rintl = __rintl
+
+/*
+ * rintl(long double x) return x rounded to integral according to
+ * the prevailing rounding direction
+ *
+ * NOTE: aintl(x), anintl(x), ceill(x), floorl(x), and rintl(x) return result
+ * with the same sign as x's, including 0.0L.
+ */
+
+#include "libm.h"
+#include "longdouble.h"
+
+extern enum fp_precision_type __swapRP(enum fp_precision_type);
+
+static const double one = 1.0;
+static const long double qzero = 0.0L;
+
+long double
+rintl(long double x) {
+	enum fp_precision_type rp;
+	long double t, w, two112;
+	int *pt = (int *) &two112;
+
+	if (!finitel(x))
+		return (x + x);
+
+	if (*(int *) &one != 0) {	/* set two112 = 2^112 */
+		pt[0] = 0x406f0000;
+		pt[1] = pt[2] = pt[3] = 0;
+	} else {
+		pt[3] = 0x406f0000;
+		pt[0] = pt[1] = pt[2] = 0;
+	}
+
+	if (fabsl(x) >= two112)
+		return (x);	/* already an integer */
+	t = copysignl(two112, x);
+	rp = __swapRP(fp_extended);	/* make sure precision is long double */
+	w = x + t;			/* x+sign(x)*2^112 rounded to integer */
+	(void) __swapRP(rp);		/* restore precision mode */
+	if (w == t)
+		return (copysignl(qzero, x));	/* x rounded to zero */
+	else
+		return (w - t);
+}