1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * CDDL HEADER START
3*0Sstevel@tonic-gate *
4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*0Sstevel@tonic-gate * with the License.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate * and limitations under the License.
13*0Sstevel@tonic-gate *
14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate *
20*0Sstevel@tonic-gate * CDDL HEADER END
21*0Sstevel@tonic-gate */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
24*0Sstevel@tonic-gate * Use is subject to license terms.
25*0Sstevel@tonic-gate */
26*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI"
27*0Sstevel@tonic-gate
28*0Sstevel@tonic-gate /*
29*0Sstevel@tonic-gate * Architecture specific definition for bitmap related routines.
30*0Sstevel@tonic-gate * These may be implemented using ISA specific instructions.
31*0Sstevel@tonic-gate */
32*0Sstevel@tonic-gate #include <sys/bitmap.h>
33*0Sstevel@tonic-gate
34*0Sstevel@tonic-gate /*
35*0Sstevel@tonic-gate * Find highest one bit set.
36*0Sstevel@tonic-gate * Returns bit number + 1 of highest bit that is set, otherwise returns 0.
37*0Sstevel@tonic-gate * High order bit is 31 (or 63 in _LP64 kernel).
38*0Sstevel@tonic-gate */
39*0Sstevel@tonic-gate int
highbit(ulong_t i)40*0Sstevel@tonic-gate highbit(ulong_t i)
41*0Sstevel@tonic-gate {
42*0Sstevel@tonic-gate register int h = 1;
43*0Sstevel@tonic-gate
44*0Sstevel@tonic-gate if (i == 0)
45*0Sstevel@tonic-gate return (0);
46*0Sstevel@tonic-gate #ifdef _LP64
47*0Sstevel@tonic-gate if (i & 0xffffffff00000000ul) {
48*0Sstevel@tonic-gate h += 32; i >>= 32;
49*0Sstevel@tonic-gate }
50*0Sstevel@tonic-gate #endif
51*0Sstevel@tonic-gate if (i & 0xffff0000) {
52*0Sstevel@tonic-gate h += 16; i >>= 16;
53*0Sstevel@tonic-gate }
54*0Sstevel@tonic-gate if (i & 0xff00) {
55*0Sstevel@tonic-gate h += 8; i >>= 8;
56*0Sstevel@tonic-gate }
57*0Sstevel@tonic-gate if (i & 0xf0) {
58*0Sstevel@tonic-gate h += 4; i >>= 4;
59*0Sstevel@tonic-gate }
60*0Sstevel@tonic-gate if (i & 0xc) {
61*0Sstevel@tonic-gate h += 2; i >>= 2;
62*0Sstevel@tonic-gate }
63*0Sstevel@tonic-gate if (i & 0x2) {
64*0Sstevel@tonic-gate h += 1;
65*0Sstevel@tonic-gate }
66*0Sstevel@tonic-gate return (h);
67*0Sstevel@tonic-gate }
68*0Sstevel@tonic-gate
69*0Sstevel@tonic-gate /*
70*0Sstevel@tonic-gate * Find lowest one bit set.
71*0Sstevel@tonic-gate * Returns bit number + 1 of lowest bit that is set, otherwise returns 0.
72*0Sstevel@tonic-gate * Low order bit is 0.
73*0Sstevel@tonic-gate */
74*0Sstevel@tonic-gate int
lowbit(ulong_t i)75*0Sstevel@tonic-gate lowbit(ulong_t i)
76*0Sstevel@tonic-gate {
77*0Sstevel@tonic-gate register int h = 1;
78*0Sstevel@tonic-gate
79*0Sstevel@tonic-gate if (i == 0)
80*0Sstevel@tonic-gate return (0);
81*0Sstevel@tonic-gate
82*0Sstevel@tonic-gate #ifdef _LP64
83*0Sstevel@tonic-gate if (!(i & 0xffffffff)) {
84*0Sstevel@tonic-gate h += 32; i >>= 32;
85*0Sstevel@tonic-gate }
86*0Sstevel@tonic-gate #endif
87*0Sstevel@tonic-gate if (!(i & 0xffff)) {
88*0Sstevel@tonic-gate h += 16; i >>= 16;
89*0Sstevel@tonic-gate }
90*0Sstevel@tonic-gate if (!(i & 0xff)) {
91*0Sstevel@tonic-gate h += 8; i >>= 8;
92*0Sstevel@tonic-gate }
93*0Sstevel@tonic-gate if (!(i & 0xf)) {
94*0Sstevel@tonic-gate h += 4; i >>= 4;
95*0Sstevel@tonic-gate }
96*0Sstevel@tonic-gate if (!(i & 0x3)) {
97*0Sstevel@tonic-gate h += 2; i >>= 2;
98*0Sstevel@tonic-gate }
99*0Sstevel@tonic-gate if (!(i & 0x1)) {
100*0Sstevel@tonic-gate h += 1;
101*0Sstevel@tonic-gate }
102*0Sstevel@tonic-gate return (h);
103*0Sstevel@tonic-gate }
104