xref: /xnu-12377.1.9/tests/unit/bits_test.c (revision f6217f891ac0bb64f3d375211650a4c1ff8ca1ea)
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28 
29 #include <darwintest.h>
30 #include "mocks/unit_test_utils.h"
31 #include <kern/bits.h>
32 
33 #define UT_MODULE osfmk
34 T_GLOBAL_META(
35 	T_META_NAMESPACE("xnu.scheduler"),
36 	T_META_RADAR_COMPONENT_NAME("xnu"),
37 	T_META_RADAR_COMPONENT_VERSION("scheduler"),
38 	T_META_TAG_VM_PREFERRED
39 	);
40 
41 T_DECL(xnu_bits, "snapshot tests for bit manipulation routines")
42 {
43 	T_EXPECT_EQ(bit_first(0ULL), -1, "bit_first");
44 	T_EXPECT_EQ(lsb_first(0ULL), -1, "lsb_first");
45 
46 	for (int i = 0; i < 64; i++) {
47 		T_EXPECT_EQ(bit_first(BIT(i)), i, "bit_first");
48 		T_EXPECT_EQ(lsb_first(BIT(i)), i, "lsb_first");
49 
50 		T_EXPECT_EQ(bit_first(mask(i)), i - 1, "bit_first");
51 		T_EXPECT_EQ(lsb_first(mask(i)), i > 0 ? 0 : -1, "lsb_first");
52 
53 		T_EXPECT_EQ(bit_next(0ULL, i), -1, "bit_next");
54 		T_EXPECT_EQ(lsb_next(0ULL, i), -1, "lsb_next");
55 
56 		T_EXPECT_EQ(bit_next(~(0ULL), i), i - 1, "bit_next");
57 		T_EXPECT_EQ(lsb_next(~(0ULL), i), i < 63 ? i + 1 : -1, "lsb_next");
58 	}
59 }
60