1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
24 */
25 /*
26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
27 * Use is subject to license terms.
28 */
29
30 #pragma weak fminf = __fminf
31
32 #include "libm.h" /* for islessequal macro */
33
34 float
__fminf(float x,float y)35 __fminf(float x, float y) {
36 /*
37 * On SPARC v8plus/v9, this could be implemented as follows
38 * (assuming %f0 = x, %f1 = y, return value left in %f0):
39 *
40 * fcmps %fcc0,%f1,%f1
41 * fmovsu %fcc0,%f0,%f1
42 * fcmps %fcc0,%f0,%f1
43 * fmovsug %fcc0,%f1,%f0
44 * st %f0,[x]
45 * st %f1,[y]
46 * ld [x],%l0
47 * ld [y],%l1
48 * or %l0,%l1,%l2
49 * sethi %hi(0x80000000),%l3
50 * and %l3,%l2,%l2
51 * or %l0,%l2,%l0
52 * st %l0,[x]
53 * ld [x],%f0
54 *
55 * If VIS instructions are available, use this code instead:
56 *
57 * fcmps %fcc0,%f1,%f1
58 * fmovsu %fcc0,%f0,%f1
59 * fcmps %fcc0,%f0,%f1
60 * fmovsug %fcc0,%f1,%f0
61 * fors %f0,%f1,%f2
62 * fzeros %f3
63 * fnegs %f3,%f3
64 * fands %f3,%f2,%f2
65 * fors %f0,%f2,%f0
66 *
67 * If VIS 3.0 instructions are available, use this:
68 *
69 * flcmps %fcc0,%f0,%f1
70 * fmovsge %fcc0,%f1,%f0 ! move if %fcc0 is 0 or 2
71 */
72
73 union {
74 unsigned i;
75 float f;
76 } xx, yy;
77 unsigned s;
78
79 /* if y is nan, replace it by x */
80 if (y != y)
81 y = x;
82
83 /* if x is nan, replace it by y */
84 if (x != x)
85 x = y;
86
87 /* At this point, x and y are either both numeric, or both NaN */
88 if (!isnan(x) && !islessequal(x, y))
89 x = y;
90
91 /*
92 * set the sign of the result if either x or y has its sign set
93 */
94 xx.f = x;
95 yy.f = y;
96 s = (xx.i | yy.i) & 0x80000000;
97 xx.i |= s;
98
99 return (xx.f);
100 }
101