--- /dev/null	Sat May 10 12:09:28 2014
+++ new/usr/src/lib/libm/common/m9x/fmaxf.c	Sat May 10 12:09:28 2014
@@ -0,0 +1,143 @@
+/*
+ * 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.
+ */
+
+#if defined(ELFOBJ)
+#pragma weak fmaxf = __fmaxf
+#endif
+
+/*
+ * fmax(x,y) returns the larger of x and y.  If just one of the
+ * arguments is NaN, fmax returns the other argument.  If both
+ * arguments are NaN, fmax returns NaN (ideally, one of the
+ * argument NaNs).
+ *
+ * C99 does not require that fmax(-0,+0) = fmax(+0,-0) = +0, but
+ * ideally fmax should satisfy this.
+ *
+ * C99 makes no mention of exceptions for fmax.  I suppose ideally
+ * either fmax never raises any exceptions or else it raises the
+ * invalid operation exception if and only if some argument is a
+ * signaling NaN.  In the former case, fmax should always return
+ * one of its arguments.  In the latter, fmax shouldn't return a
+ * signaling NaN, although when both arguments are signaling NaNs,
+ * this ideal is at odds with the stipulation that fmax should
+ * always return one of its arguments.
+ *
+ * Commutativity of fmax follows from the properties listed above
+ * except when both arguments are NaN.  In that case, fmax may be
+ * declared commutative by fiat because there is no portable way
+ * to tell different NaNs apart.  Ideally fmax would be truly com-
+ * mutative for all arguments.
+ *
+ * On SPARC V8, fmax must involve tests and branches.  Ideally,
+ * an implementation on SPARC V9 should avoid branching, using
+ * conditional moves instead where necessary, and be as efficient
+ * as possible in its use of other resources.
+ *
+ * It appears to be impossible to attain all of the aforementioned
+ * ideals simultaneously.  The implementation below satisfies the
+ * following (on SPARC):
+ *
+ * 1. fmax(x,y) returns the larger of x and y if neither x nor y
+ *    is NaN and the non-NaN argument if just one of x or y is NaN.
+ *    If both x and y are NaN, fmax(x,y) returns x unchanged.
+ * 2. fmax(-0,+0) = fmax(+0,-0) = +0.
+ * 3. If either argument is a signaling NaN, fmax raises the invalid
+ *    operation exception.  Otherwise, it raises no exceptions.
+ */
+
+#include "libm.h"	/* for isgreaterequal macro */
+
+float
+__fmaxf(float x, float y) {
+	/*
+	 * On SPARC v8plus/v9, this could be implemented as follows
+	 * (assuming %f0 = x, %f1 = y, return value left in %f0):
+	 *
+	 * fcmps	%fcc0,%f1,%f1
+	 * fmovsu	%fcc0,%f0,%f1
+	 * fcmps	%fcc0,%f0,%f1
+	 * fmovsul	%fcc0,%f1,%f0
+	 * st		%f0,[x]
+	 * st		%f1,[y]
+	 * ld		[x],%l0
+	 * ld		[y],%l1
+	 * and		%l0,%l1,%l2
+	 * sethi	%hi(0x80000000),%l3
+	 * andn		%l3,%l2,%l2
+	 * andn		%l0,%l2,%l0
+	 * st		%l0,[x]
+	 * ld		[x],%f0
+	 *
+	 * If VIS instructions are available, use this code instead:
+	 *
+	 * fcmps	%fcc0,%f1,%f1
+	 * fmovsu	%fcc0,%f0,%f1
+	 * fcmps	%fcc0,%f0,%f1
+	 * fmovsul	%fcc0,%f1,%f0
+	 * fands	%f0,%f1,%f2
+	 * fzeros	%f3
+	 * fnegs	%f3,%f3
+	 * fandnot2s %f3,%f2,%f2
+	 * fandnot2s %f0,%f2,%f0
+	 *
+	 * If VIS 3.0 instructions are available, use this:
+	 *
+	 * flcmps	%fcc0,%f0,%f1
+	 * fmovslg	%fcc0,%f1,%f0	! move if %fcc0 is 1 or 2
+	 */
+
+	union {
+		unsigned i;
+		float f;
+	} xx, yy;
+	unsigned s;
+
+	/* if y is nan, replace it by x */
+	if (y != y)
+		y = x;
+
+	/* if x is nan, replace it by y */
+	if (x != x)
+		x = y;
+
+	/* At this point, x and y are either both numeric, or both NaN */
+	if (!isnan(x) && !isgreaterequal(x, y))
+		x = y;
+
+	/*
+	 * clear the sign of the result if either x or y has its sign clear
+	 */
+	xx.f = x;
+	yy.f = y;
+	s = ~(xx.i & yy.i) & 0x80000000;
+	xx.i &= ~s;
+
+	return (xx.f);
+}
