1 /*	$NetBSD: t_bitops.c,v 1.16 2012/12/07 02:28:19 christos Exp $ */
2 
3 /*-
4  * Copyright (c) 2011, 2012 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas and Jukka Ruohonen.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: t_bitops.c,v 1.16 2012/12/07 02:28:19 christos Exp $");
33 
34 #include <atf-c.h>
35 
36 #include <sys/cdefs.h>
37 #include <sys/bitops.h>
38 
39 #include <math.h>
40 #include <inttypes.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 static const struct {
45 	uint32_t	val;
46 	int		ffs;
47 	int		fls;
48 } bits[] = {
49 
50 	{ 0x00, 0, 0 }, { 0x01, 1, 1 },	{ 0x02, 2, 2 },	{ 0x03, 1, 2 },
51 	{ 0x04, 3, 3 }, { 0x05, 1, 3 },	{ 0x06, 2, 3 },	{ 0x07, 1, 3 },
52 	{ 0x08, 4, 4 }, { 0x09, 1, 4 },	{ 0x0A, 2, 4 },	{ 0x0B, 1, 4 },
53 	{ 0x0C, 3, 4 }, { 0x0D, 1, 4 },	{ 0x0E, 2, 4 },	{ 0x0F, 1, 4 },
54 
55 	{ 0x10, 5, 5 },	{ 0x11, 1, 5 },	{ 0x12, 2, 5 },	{ 0x13, 1, 5 },
56 	{ 0x14, 3, 5 },	{ 0x15, 1, 5 },	{ 0x16, 2, 5 },	{ 0x17, 1, 5 },
57 	{ 0x18, 4, 5 },	{ 0x19, 1, 5 },	{ 0x1A, 2, 5 },	{ 0x1B, 1, 5 },
58 	{ 0x1C, 3, 5 },	{ 0x1D, 1, 5 },	{ 0x1E, 2, 5 },	{ 0x1F, 1, 5 },
59 
60 	{ 0xF0, 5, 8 },	{ 0xF1, 1, 8 },	{ 0xF2, 2, 8 },	{ 0xF3, 1, 8 },
61 	{ 0xF4, 3, 8 },	{ 0xF5, 1, 8 },	{ 0xF6, 2, 8 },	{ 0xF7, 1, 8 },
62 	{ 0xF8, 4, 8 },	{ 0xF9, 1, 8 },	{ 0xFA, 2, 8 },	{ 0xFB, 1, 8 },
63 	{ 0xFC, 3, 8 },	{ 0xFD, 1, 8 },	{ 0xFE, 2, 8 },	{ 0xFF, 1, 8 },
64 
65 };
66 
67 ATF_TC(bitmap_basic);
68 ATF_TC_HEAD(bitmap_basic, tc)
69 {
70         atf_tc_set_md_var(tc, "descr", "A basic test of __BITMAP_*");
71 }
72 
73 ATF_TC_BODY(bitmap_basic, tc)
74 {
75 	__BITMAP_TYPE(, uint32_t, 65536) bm;
76 	__BITMAP_ZERO(&bm);
77 
78 	ATF_REQUIRE(__BITMAP_SIZE(uint32_t, 65536) == 2048);
79 
80 	ATF_REQUIRE(__BITMAP_SHIFT(uint32_t) == 5);
81 
82 	ATF_REQUIRE(__BITMAP_MASK(uint32_t) == 31);
83 
84 	for (size_t i = 0; i < 65536; i += 2)
85 		__BITMAP_SET(i, &bm);
86 
87 	for (size_t i = 0; i < 2048; i++)
88 		ATF_REQUIRE(bm._b[i] == 0x55555555);
89 
90 	for (size_t i = 0; i < 65536; i++)
91 		if (i & 1)
92 			ATF_REQUIRE(!__BITMAP_ISSET(i, &bm));
93 		else {
94 			ATF_REQUIRE(__BITMAP_ISSET(i, &bm));
95 			__BITMAP_CLR(i, &bm);
96 		}
97 
98 	for (size_t i = 0; i < 65536; i += 2)
99 		ATF_REQUIRE(!__BITMAP_ISSET(i, &bm));
100 }
101 
102 ATF_TC(fast_divide32);
103 ATF_TC_HEAD(fast_divide32, tc)
104 {
105 	atf_tc_set_md_var(tc, "descr", "A basic test of fast_divide32(3)");
106 }
107 
108 ATF_TC_BODY(fast_divide32, tc)
109 {
110 	uint32_t a, b, q, r, m;
111 	uint8_t i, s1, s2;
112 
113 	a = 0xFFFF;
114 	b = 0x000F;
115 
116 	fast_divide32_prepare(b, &m, &s1, &s2);
117 
118 	q = fast_divide32(a, b, m, s1, s2);
119 	r = fast_remainder32(a, b, m, s1, s2);
120 
121 	ATF_REQUIRE(q == 0x1111 && r == 0);
122 
123 	for (i = 1; i < __arraycount(bits); i++) {
124 
125 		a = bits[i].val;
126 		b = bits[i].ffs;
127 
128 		fast_divide32_prepare(b, &m, &s1, &s2);
129 
130 		q = fast_divide32(a, b, m, s1, s2);
131 		r = fast_remainder32(a, b, m, s1, s2);
132 
133 		ATF_REQUIRE(q == a / b);
134 		ATF_REQUIRE(r == a % b);
135 	}
136 }
137 
138 ATF_TC(ffsfls);
139 ATF_TC_HEAD(ffsfls, tc)
140 {
141 	atf_tc_set_md_var(tc, "descr", "Test ffs32(3)-family for correctness");
142 }
143 
144 ATF_TC_BODY(ffsfls, tc)
145 {
146 	uint8_t i;
147 
148 	ATF_REQUIRE(ffs32(0) == 0x00);
149 	ATF_REQUIRE(fls32(0) == 0x00);
150 	ATF_REQUIRE(ffs64(0) == 0x00);
151 	ATF_REQUIRE(fls64(0) == 0x00);
152 
153 	ATF_REQUIRE(ffs32(UINT32_MAX) == 0x01);
154 	ATF_REQUIRE(fls32(UINT32_MAX) == 0x20);
155 	ATF_REQUIRE(ffs64(UINT64_MAX) == 0x01);
156 	ATF_REQUIRE(fls64(UINT64_MAX) == 0x40);
157 
158 	for (i = 1; i < __arraycount(bits); i++) {
159 
160 		ATF_REQUIRE(ffs32(bits[i].val) == bits[i].ffs);
161 		ATF_REQUIRE(fls32(bits[i].val) == bits[i].fls);
162 		ATF_REQUIRE(ffs64(bits[i].val) == bits[i].ffs);
163 		ATF_REQUIRE(fls64(bits[i].val) == bits[i].fls);
164 
165 		ATF_REQUIRE(ffs32(bits[i].val << 1) == bits[i].ffs + 1);
166 		ATF_REQUIRE(fls32(bits[i].val << 1) == bits[i].fls + 1);
167 		ATF_REQUIRE(ffs64(bits[i].val << 1) == bits[i].ffs + 1);
168 		ATF_REQUIRE(fls64(bits[i].val << 1) == bits[i].fls + 1);
169 
170 		ATF_REQUIRE(ffs32(bits[i].val << 9) == bits[i].ffs + 9);
171 		ATF_REQUIRE(fls32(bits[i].val << 9) == bits[i].fls + 9);
172 		ATF_REQUIRE(ffs64(bits[i].val << 9) == bits[i].ffs + 9);
173 		ATF_REQUIRE(fls64(bits[i].val << 9) == bits[i].fls + 9);
174 	}
175 }
176 
177 ATF_TC(ilog2_basic);
178 ATF_TC_HEAD(ilog2_basic, tc)
179 {
180 	atf_tc_set_md_var(tc, "descr", "Test ilog2(3) for correctness");
181 }
182 
183 ATF_TC_BODY(ilog2_basic, tc)
184 {
185 	uint64_t i, x;
186 
187 	for (i = x = 0; i < 64; i++) {
188 
189 		x = (uint64_t)1 << i;
190 
191 		ATF_REQUIRE(i == (uint64_t)ilog2(x));
192 	}
193 }
194 
195 ATF_TC(ilog2_log2);
196 ATF_TC_HEAD(ilog2_log2, tc)
197 {
198 	atf_tc_set_md_var(tc, "descr", "Test log2(3) vs. ilog2(3)");
199 }
200 
201 ATF_TC_BODY(ilog2_log2, tc)
202 {
203 #ifdef __vax__
204 	atf_tc_skip("Test is unavailable on vax because of lack of log2()");
205 #else
206 	double  x, y;
207 	uint64_t i;
208 
209 	/*
210 	 * This may fail under QEMU; see PR misc/44767.
211 	 */
212 	for (i = 1; i < UINT32_MAX; i += UINT16_MAX) {
213 
214 		x = log2(i);
215 		y = (double)(ilog2(i));
216 
217 		ATF_REQUIRE(ceil(x) >= y);
218 
219 		if (fabs(floor(x) - y) > 1.0e-40) {
220 			atf_tc_expect_fail("PR misc/44767");
221 			atf_tc_fail("log2(%"PRIu64") != "
222 			    "ilog2(%"PRIu64")", i, i);
223 		}
224 	}
225 #endif
226 }
227 
228 ATF_TP_ADD_TCS(tp)
229 {
230 
231         ATF_TP_ADD_TC(tp, bitmap_basic);
232 	ATF_TP_ADD_TC(tp, fast_divide32);
233 	ATF_TP_ADD_TC(tp, ffsfls);
234 	ATF_TP_ADD_TC(tp, ilog2_basic);
235 	ATF_TP_ADD_TC(tp, ilog2_log2);
236 
237 	return atf_no_error();
238 }
239