21 	unsigned int expected_ffs64_0based; /* __ffs64() result (0-based) */
30 	{0x00000000, 0, 0, "zero value"},
33 	{0x00000001, 1, 1, "bit 0 set"},
34 	{0x00000002, 2, 2, "bit 1 set"},
35 	{0x00000004, 3, 3, "bit 2 set"},
36 	{0x00000008, 4, 4, "bit 3 set"},
37 	{0x00000010, 5, 5, "bit 4 set"},
38 	{0x00000020, 6, 6, "bit 5 set"},
39 	{0x00000040, 7, 7, "bit 6 set"},
40 	{0x00000080, 8, 8, "bit 7 set"},
41 	{0x00000100, 9, 9, "bit 8 set"},
42 	{0x00008000, 16, 16, "bit 15 set"},
43 	{0x00010000, 17, 17, "bit 16 set"},
44 	{0x40000000, 31, 31, "bit 30 set"},
45 	{0x80000000, 32, 32, "bit 31 set (sign bit)"},
48 	{0xFFFFFFFF, 1, 32, "all bits set"},
51 	{0x00000003, 1, 2, "bits 0-1 set"},
52 	{0x00000007, 1, 3, "bits 0-2 set"},
53 	{0x0000000F, 1, 4, "bits 0-3 set"},
54 	{0x000000FF, 1, 8, "bits 0-7 set"},
55 	{0x0000FFFF, 1, 16, "bits 0-15 set"},
56 	{0x7FFFFFFF, 1, 31, "bits 0-30 set"},
59 	{0x00000101, 1, 9, "bits 0,8 set"},
60 	{0x00001001, 1, 13, "bits 0,12 set"},
61 	{0x80000001, 1, 32, "bits 0,31 set"},
62 	{0x40000002, 2, 31, "bits 1,30 set"},
70 	{0x0000000000000000ULL, 0, 0, "zero value"},
73 	{0x0000000000000001ULL, 1, 0, "bit 0 set"},
74 	{0x0000000000000002ULL, 2, 1, "bit 1 set"},
75 	{0x0000000000000004ULL, 3, 2, "bit 2 set"},
76 	{0x0000000000000008ULL, 4, 3, "bit 3 set"},
77 	{0x0000000000008000ULL, 16, 15, "bit 15 set"},
78 	{0x0000000000010000ULL, 17, 16, "bit 16 set"},
79 	{0x0000000080000000ULL, 32, 31, "bit 31 set"},
80 	{0x0000000100000000ULL, 33, 32, "bit 32 set"},
81 	{0x0000000200000000ULL, 34, 33, "bit 33 set"},
82 	{0x4000000000000000ULL, 63, 62, "bit 62 set"},
83 	{0x8000000000000000ULL, 64, 63, "bit 63 set (sign bit)"},
86 	{0xFFFFFFFFFFFFFFFFULL, 64, 0, "all bits set"},
89 	{0x00000000FFFFFFFFULL, 32, 0, "lower 32 bits set"},
90 	{0xFFFFFFFF00000000ULL, 64, 32, "upper 32 bits set"},
91 	{0x8000000000000001ULL, 64, 0, "bits 0,63 set"},
92 	{0x4000000000000002ULL, 63, 1, "bits 1,62 set"},
95 	{0x00000001FFFFFFFFULL, 33, 0, "bit 32 + lower 32 bits"},
96 	{0xFFFFFFFF80000000ULL, 64, 31, "upper 32 bits + bit 31"},
107 			    "%s(0x%08lx) [%s]: expected %d, got %d",  in validate_ffs_result()
119 			    "%s(0x%016llx) [%s]: expected %d, got %d",  in validate_ffs64_result()
133 	if (input == 0) {  in validate_ffs_relationships()
135 		KUNIT_EXPECT_EQ(test, ffs(input), 0);  in validate_ffs_relationships()
136 		KUNIT_EXPECT_EQ(test, fls(input), 0);  in validate_ffs_relationships()
137 		/* __ffs and __fls are undefined for 0, but often return specific values */  in validate_ffs_relationships()
146 	/* Relationship: ffs(x) == __ffs(x) + 1 for x != 0 */  in validate_ffs_relationships()
148 			    "ffs(0x%08lx) != __ffs(0x%08lx) + 1: %d != %u + 1",  in validate_ffs_relationships()
151 	/* Relationship: fls(x) == __fls(x) + 1 for x != 0 */  in validate_ffs_relationships()
153 			    "fls(0x%08lx) != __fls(0x%08lx) + 1: %d != %u + 1",  in validate_ffs_relationships()
171 	if (input == 0) {  in validate_ffs64_relationships()
172 		KUNIT_EXPECT_EQ(test, fls64(input), 0);  in validate_ffs64_relationships()
188 	if (input <= 0xFFFFFFFFULL) {  in validate_ffs64_relationships()
191 				    "fls64(0x%llx) != fls(0x%lx): %d != %d",  in validate_ffs64_relationships()
194 		if (input != 0) {  in validate_ffs64_relationships()
196 					    "__ffs64(0x%llx) != __ffs(0x%lx): %lu != %lu",  in validate_ffs64_relationships()
211 	for (i = 0; i < ARRAY_SIZE(basic_test_cases); i++) {  in ffs_basic_correctness_test()
223 		if (tc->input != 0) {  in ffs_basic_correctness_test()
231 		if (tc->input != 0) {  in ffs_basic_correctness_test()
247 	for (i = 0; i < ARRAY_SIZE(ffs64_test_cases); i++) {  in ffs64_correctness_test()
255 		if (tc->input != 0) {  in ffs64_correctness_test()
271 	for (i = 0; i < ARRAY_SIZE(basic_test_cases); i++) {  in ffs_mathematical_relationships_test()
276 	for (i = 0; i < ARRAY_SIZE(ffs64_test_cases); i++) {  in ffs_mathematical_relationships_test()
296 		0x7FFFFFFFUL,	/* Maximum positive 32-bit */  in ffs_edge_cases_test()
297 		0x80000000UL,	/* Minimum negative 32-bit */  in ffs_edge_cases_test()
298 		0xFFFFFFFFUL,	/* Maximum 32-bit unsigned */  in ffs_edge_cases_test()
302 	for (i = 0; i < ARRAY_SIZE(test_patterns); i++) {  in ffs_edge_cases_test()
314 		0x0000000100000000ULL,	/* 2^32 */  in ffs64_edge_cases_test()
315 		0x0000000200000000ULL,	/* 2^33 */  in ffs64_edge_cases_test()
316 		0x0000000400000000ULL,	/* 2^34 */  in ffs64_edge_cases_test()
317 		0x0000001000000000ULL,	/* 2^36 */  in ffs64_edge_cases_test()
318 		0x0000010000000000ULL,	/* 2^40 */  in ffs64_edge_cases_test()
319 		0x0001000000000000ULL,	/* 2^48 */  in ffs64_edge_cases_test()
320 		0x0100000000000000ULL,	/* 2^56 */  in ffs64_edge_cases_test()
321 		0x4000000000000000ULL,	/* 2^62 */  in ffs64_edge_cases_test()
322 		0x8000000000000000ULL,	/* 2^63 */  in ffs64_edge_cases_test()
325 		0x00000000FFFFFFFFULL,	/* Lower 32 bits */  in ffs64_edge_cases_test()
326 		0xFFFFFFFF00000000ULL,	/* Upper 32 bits */  in ffs64_edge_cases_test()
327 		0x7FFFFFFFFFFFFFFFULL,	/* Maximum positive 64-bit */  in ffs64_edge_cases_test()
328 		0xFFFFFFFFFFFFFFFFULL,	/* Maximum 64-bit unsigned */  in ffs64_edge_cases_test()
332 	for (i = 0; i < ARRAY_SIZE(test_patterns_64); i++) {  in ffs64_edge_cases_test()
348 	{0xFFFFFFFE, 0, "bit 0 is zero"},      /* ...11111110 */
349 	{0xFFFFFFFD, 1, "bit 1 is zero"},      /* ...11111101 */
350 	{0xFFFFFFFB, 2, "bit 2 is zero"},      /* ...11111011 */
351 	{0xFFFFFFF7, 3, "bit 3 is zero"},      /* ...11110111 */
352 	{0xFFFFFFEF, 4, "bit 4 is zero"},      /* ...11101111 */
353 	{0xFFFFFFDF, 5, "bit 5 is zero"},      /* ...11011111 */
354 	{0xFFFFFFBF, 6, "bit 6 is zero"},      /* ...10111111 */
355 	{0xFFFFFF7F, 7, "bit 7 is zero"},      /* ...01111111 */
356 	{0xFFFFFEFF, 8, "bit 8 is zero"},      /* Gap in bit 8 */
357 	{0xFFFF7FFF, 15, "bit 15 is zero"},    /* Gap in bit 15 */
358 	{0xFFFEFFFF, 16, "bit 16 is zero"},    /* Gap in bit 16 */
359 	{0xBFFFFFFF, 30, "bit 30 is zero"},    /* Gap in bit 30 */
360 	{0x7FFFFFFF, 31, "bit 31 is zero"},    /* 01111111... */
363 	{0xFFFFFFFC, 0, "bits 0-1 are zero"},  /* ...11111100 */
364 	{0xFFFFFFF8, 0, "bits 0-2 are zero"},  /* ...11111000 */
365 	{0xFFFFFFF0, 0, "bits 0-3 are zero"},  /* ...11110000 */
366 	{0xFFFFFF00, 0, "bits 0-7 are zero"},  /* ...00000000 */
367 	{0xFFFF0000, 0, "bits 0-15 are zero"}, /* Lower 16 bits zero */
370 	{0x00000000, 0, "all bits zero"},
373 	{0xFFFDFFFF, 17, "bit 17 is zero"},    /* Gap in bit 17 */
374 	{0xFFF7FFFF, 19, "bit 19 is zero"},    /* Gap in bit 19 */
375 	{0xF7FFFFFF, 27, "bit 27 is zero"},    /* Gap in bit 27 */
376 	{0xDFFFFFFF, 29, "bit 29 is zero"},    /* Gap in bit 29 */
386 	for (i = 0; i < ARRAY_SIZE(ffz_test_cases); i++) {  in ffz_basic_correctness_test()
391 				    "ffz(0x%08lx) [%s]: expected %lu, got %lu",  in ffz_basic_correctness_test()
403 	if (input == 0) {  in validate_ffz_relationships()
404 		/* ffz(0) should return 0 (first zero bit is at position 0) */  in validate_ffz_relationships()
405 		KUNIT_EXPECT_EQ(test, ffz(input), 0);  in validate_ffz_relationships()
409 	if (input == ~0UL) {  in validate_ffz_relationships()
410 		/* ffz(~0) is undefined (no zero bits) - just verify it doesn't crash */  in validate_ffz_relationships()
422 	KUNIT_EXPECT_EQ_MSG(test, (input >> ffz_result) & 1, 0,  in validate_ffz_relationships()
423 			    "ffz(0x%08lx) = %lu, but bit %lu is not zero",  in validate_ffz_relationships()
429 		if (modified != ~0UL) { /* Skip if all bits would be set */  in validate_ffz_relationships()
432 					    "ffz(0x%08lx) = %lu, but setting that bit doesn't change ffz result",  in validate_ffz_relationships()
442 		0xFFFFFFFE, 0xFFFFFFFD, 0xFFFFFFFB, 0xFFFFFFF7,  in ffz_mathematical_relationships_test()
443 		0xFFFFFFEF, 0xFFFFFFDF, 0xFFFFFFBF, 0xFFFFFF7F,  in ffz_mathematical_relationships_test()
446 		0xFFFFFF00, 0xFFFFF000, 0xFFFF0000, 0xFFF00000,  in ffz_mathematical_relationships_test()
447 		0x7FFFFFFF, 0x3FFFFFFF, 0x1FFFFFFF, 0x0FFFFFFF,  in ffz_mathematical_relationships_test()
450 		0xAAAAAAAA, 0x55555555, 0xCCCCCCCC, 0x33333333,  in ffz_mathematical_relationships_test()
451 		0xF0F0F0F0, 0x0F0F0F0F, 0xFF00FF00, 0x00FF00FF,  in ffz_mathematical_relationships_test()
456 	for (i = 0; i < ARRAY_SIZE(ffz_test_cases); i++) {  in ffz_mathematical_relationships_test()
461 	for (i = 0; i < ARRAY_SIZE(test_patterns); i++) {  in ffz_mathematical_relationships_test()
473 		0x00000000,  /* All zeros */  in ffz_edge_cases_test()
474 		0x80000000,  /* Only MSB set */  in ffz_edge_cases_test()
475 		0x00000001,  /* Only LSB set */  in ffz_edge_cases_test()
476 		0x7FFFFFFF,  /* MSB clear */  in ffz_edge_cases_test()
477 		0xFFFFFFFE,  /* LSB clear */  in ffz_edge_cases_test()
480 		~(1UL << 0),  ~(1UL << 1),  ~(1UL << 2),  ~(1UL << 3),  in ffz_edge_cases_test()
484 		0xFFFFFFFE, 0xFFFFFFFD, 0xFFFFFFFB, 0xFFFFFFF7,  in ffz_edge_cases_test()
485 		0xFFFFFFEF, 0xFFFFFFDF, 0xFFFFFFBF, 0xFFFFFF7F,  in ffz_edge_cases_test()
486 		0xFFFFFEFF, 0xFFFFFDFF, 0xFFFFFBFF, 0xFFFFF7FF,  in ffz_edge_cases_test()
489 		0xFFFFFF00, 0xFFFFF000, 0xFFFF0000, 0xFFF00000,  in ffz_edge_cases_test()
490 		0xFF000000, 0xF0000000, 0x00000000,  in ffz_edge_cases_test()
494 	for (i = 0; i < ARRAY_SIZE(edge_patterns); i++) {  in ffz_edge_cases_test()