2 * Copyright (c) 2011, 2012 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
24 #include "byte-order.h"
29 check_log_2_floor(uint32_t x, int n)
31 if (log_2_floor(x) != n) {
32 fprintf(stderr, "log_2_floor(%"PRIu32") is %d but should be %d\n",
33 x, log_2_floor(x), n);
39 check_ctz(uint32_t x, int n)
42 fprintf(stderr, "ctz(%"PRIu32") is %d but should be %d\n",
48 /* Returns the sum of the squares of the first 'n' positive integers. */
52 return n * (n + 1) * (2 * n + 1) / 6;
56 check_bitwise_copy(void)
64 for (n_bits = 0; n_bits <= 64; n_bits++) {
65 for (src_ofs = 0; src_ofs < 64 - n_bits; src_ofs++) {
66 for (dst_ofs = 0; dst_ofs < 64 - n_bits; dst_ofs++) {
67 ovs_be64 src = htonll(random_uint64());
68 ovs_be64 dst = htonll(random_uint64());
69 ovs_be64 orig_dst = dst;
75 uint64_t mask = (UINT64_C(1) << n_bits) - 1;
76 expect = orig_dst & ~htonll(mask << dst_ofs);
77 expect |= htonll(((ntohll(src) >> src_ofs) & mask)
81 bitwise_copy(&src, sizeof src, src_ofs,
82 &dst, sizeof dst, dst_ofs,
85 fprintf(stderr,"copy_bits(0x%016"PRIx64",8,%d, "
86 "0x%016"PRIx64",8,%d, %d) yielded 0x%016"PRIx64" "
87 "instead of the expected 0x%016"PRIx64"\n",
89 ntohll(orig_dst), dst_ofs,
91 ntohll(dst), ntohll(expect));
100 if (n_loops != sum_of_squares(64)) {
106 check_bitwise_zero(void)
108 unsigned int n_loops;
113 for (n_bits = 0; n_bits <= 64; n_bits++) {
114 for (dst_ofs = 0; dst_ofs < 64 - n_bits; dst_ofs++) {
115 ovs_be64 dst = htonll(random_uint64());
116 ovs_be64 orig_dst = dst;
122 uint64_t mask = (UINT64_C(1) << n_bits) - 1;
123 expect = orig_dst & ~htonll(mask << dst_ofs);
126 bitwise_zero(&dst, sizeof dst, dst_ofs, n_bits);
128 fprintf(stderr,"bitwise_zero(0x%016"PRIx64",8,%d, %d) "
129 "yielded 0x%016"PRIx64" "
130 "instead of the expected 0x%016"PRIx64"\n",
131 ntohll(orig_dst), dst_ofs,
133 ntohll(dst), ntohll(expect));
141 if (n_loops != 64 * (64 + 1) / 2) {
147 check_bitwise_one(void)
149 unsigned int n_loops;
154 for (n_bits = 0; n_bits <= 64; n_bits++) {
155 for (dst_ofs = 0; dst_ofs < 64 - n_bits; dst_ofs++) {
156 ovs_be64 dst = htonll(random_uint64());
157 ovs_be64 orig_dst = dst;
161 expect = htonll(UINT64_MAX);
163 uint64_t mask = (UINT64_C(1) << n_bits) - 1;
164 expect = orig_dst | htonll(mask << dst_ofs);
167 bitwise_one(&dst, sizeof dst, dst_ofs, n_bits);
169 fprintf(stderr,"bitwise_one(0x%016"PRIx64",8,%d, %d) "
170 "yielded 0x%016"PRIx64" "
171 "instead of the expected 0x%016"PRIx64"\n",
172 ntohll(orig_dst), dst_ofs,
174 ntohll(dst), ntohll(expect));
182 if (n_loops != 64 * (64 + 1) / 2) {
188 check_bitwise_is_all_zeros(void)
192 for (n_loops = 0; n_loops < 100; n_loops++) {
193 ovs_be64 x = htonll(0);
196 for (i = 0; i < 64; i++) {
200 /* Change a random 0-bit into a 1-bit. */
202 bit = htonll(UINT64_C(1) << (random_uint32() % 64));
206 for (ofs = 0; ofs < 64; ofs++) {
207 for (n = 0; n <= 64 - ofs; n++) {
213 : !(x & htonll(((UINT64_C(1) << n) - 1)
215 answer = bitwise_is_all_zeros(&x, sizeof x, ofs, n);
216 if (expect != answer) {
218 "bitwise_is_all_zeros(0x%016"PRIx64",8,%d,%d "
219 "returned %s instead of %s\n",
221 answer ? "true" : "false",
222 expect ? "true" : "false");
236 for (n = 0; n < 32; n++) {
237 /* Check minimum x such that f(x) == n. */
238 check_log_2_floor(1 << n, n);
239 check_ctz(1 << n, n);
241 /* Check maximum x such that f(x) == n. */
242 check_log_2_floor((1 << n) | ((1 << n) - 1), n);
243 check_ctz(UINT32_MAX << n, n);
245 /* Check a random value in the middle. */
246 check_log_2_floor((random_uint32() & ((1 << n) - 1)) | (1 << n), n);
247 check_ctz((random_uint32() | 1) << n, n);
251 * (log_2_floor(0) is undefined.) */
254 check_bitwise_copy();
256 check_bitwise_zero();
260 check_bitwise_is_all_zeros();