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t_bitops.c revision 1.1 
      1 /*	$NetBSD: t_bitops.c,v 1.1 2011/03/19 06:39:17 jruoho Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2011 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by 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 
     32 #include <atf-c.h>
     33 
     34 #include <sys/bitops.h>
     35 #include <math.h>
     36 
     37 ATF_TC(ilog2_1);
     38 ATF_TC_HEAD(ilog2_1, tc)
     39 {
     40 	atf_tc_set_md_var(tc, "descr", "Test ilog2(3) for correctness");
     41 }
     42 
     43 ATF_TC_BODY(ilog2_1, tc)
     44 {
     45 	uint64_t i, x;
     46 
     47 	for (i = x = 0; i < 64; i++) {
     48 
     49 		x = (uint64_t)1 << i;
     50 
     51 		ATF_REQUIRE(i == (uint64_t)ilog2(x));
     52 	}
     53 }
     54 
     55 ATF_TC(ilog2_2);
     56 ATF_TC_HEAD(ilog2_2, tc)
     57 {
     58 	atf_tc_set_md_var(tc, "descr", "Test log2(3) vs. ilog2(3)");
     59 }
     60 
     61 ATF_TC_BODY(ilog2_2, tc)
     62 {
     63 	double  x, y;
     64 	uint64_t i;
     65 
     66 	for (i = 1; i < UINT32_MAX; i += UINT16_MAX) {
     67 
     68 		x = log2(i);
     69 		y = (double)(ilog2(i));
     70 
     71 		ATF_REQUIRE(ceil(x) >= y);
     72 		ATF_REQUIRE(fabs(floor(x) - y) < 1.0e-40);
     73 	}
     74 }
     75 
     76 ATF_TP_ADD_TCS(tp)
     77 {
     78 
     79 	ATF_TP_ADD_TC(tp, ilog2_1);
     80 	ATF_TP_ADD_TC(tp, ilog2_2);
     81 
     82 	return atf_no_error();
     83 }
     84