1 // SPDX-License-Identifier: GPL-2.0
6  * is_aligned - is this pointer & size okay for word-wide copying?
7  * @base: pointer to data
15  * For some reason, gcc doesn't know to optimize "if (a & mask || b & mask)"
16  * to "if ((a | b) & mask)", so we do that by hand.
27 	return (lsbits & (align - 1)) == 0;  in is_aligned()
31  * swap_words_32 - swap two elements in 32-bit chunks
32  * @a: pointer to the first element to swap
33  * @b: pointer to the second element to swap
37  * which basically all CPUs have, to minimize loop overhead computations.
47 		u32 t = *(u32 *)(a + (n -= 4));  in swap_words_32()
54  * swap_words_64 - swap two elements in 64-bit chunks
55  * @a: pointer to the first element to swap
56  * @b: pointer to the second element to swap
60  * addressing, which basically all CPUs have, to minimize loop overhead
63  * We'd like to use 64-bit loads if possible.  If they're not, emulating
65  * processors do not.  If CONFIG_64BIT, we definitely have 64-bit loads,
66  * but it's possible to have 64-bit loads without 64-bit pointers (e.g.
67  * x32 ABI).  Are there any cases the kernel needs to worry about?
73 		u64 t = *(u64 *)(a + (n -= 8));  in swap_words_64()
77 		/* Use two 32-bit transfers to avoid base+index+4 addressing */  in swap_words_64()
78 		u32 t = *(u32 *)(a + (n -= 4));  in swap_words_64()
82 		t = *(u32 *)(a + (n -= 4));  in swap_words_64()
90  * swap_bytes - swap two elements a byte at a time
91  * @a: pointer to the first element to swap
92  * @b: pointer to the second element to swap
100 		char t = ((char *)a)[--n];  in swap_bytes()
122  * The function pointer is last to make tail calls most efficient if the
123  * compiler decides not to inline this function.
128 		((const struct wrapper *)priv)->swap_func(a, b, (int)size);  in do_swap()
147 		return ((const struct wrapper *)priv)->cmp(a, b);  in do_cmp()
174 	int i, j, k;  in eytzinger0_sort_r()  local
177 	if (swap_func == SWAP_WRAPPER && !((struct wrapper *)priv)->swap_func)  in eytzinger0_sort_r()
190 	for (i = n / 2 - 1; i >= 0; --i) {  in eytzinger0_sort_r()
191 		/* Find the sift-down path all the way to the leaves. */  in eytzinger0_sort_r()
192 		for (j = i; k = j * 2 + 1, k + 1 < n;)  in eytzinger0_sort_r()
193 			j = eytzinger0_do_cmp(base, n, size, cmp_func, priv, k, k + 1) > 0 ? k : k + 1;  in eytzinger0_sort_r()
196 		if (j * 2 + 2 == n)  in eytzinger0_sort_r()
197 			j = j * 2 + 1;  in eytzinger0_sort_r()
199 		/* Backtrack to the correct location. */  in eytzinger0_sort_r()
200 		while (j != i && eytzinger0_do_cmp(base, n, size, cmp_func, priv, i, j) >= 0)  in eytzinger0_sort_r()
201 			j = (j - 1) / 2;  in eytzinger0_sort_r()
204 		for (k = j; j != i;) {  in eytzinger0_sort_r()
205 			j = (j - 1) / 2;  in eytzinger0_sort_r()
206 			eytzinger0_do_swap(base, n, size, swap_func, priv, j, k);  in eytzinger0_sort_r()
211 	for (i = n - 1; i > 0; --i) {  in eytzinger0_sort_r()
214 		/* Find the sift-down path all the way to the leaves. */  in eytzinger0_sort_r()
215 		for (j = 0; k = j * 2 + 1, k + 1 < i;)  in eytzinger0_sort_r()
216 			j = eytzinger0_do_cmp(base, n, size, cmp_func, priv, k, k + 1) > 0 ? k : k + 1;  in eytzinger0_sort_r()
219 		if (j * 2 + 2 == i)  in eytzinger0_sort_r()
220 			j = j * 2 + 1;  in eytzinger0_sort_r()
222 		/* Backtrack to the correct location. */  in eytzinger0_sort_r()
223 		while (j && eytzinger0_do_cmp(base, n, size, cmp_func, priv, 0, j) >= 0)  in eytzinger0_sort_r()
224 			j = (j - 1) / 2;  in eytzinger0_sort_r()
227 		for (k = j; j;) {  in eytzinger0_sort_r()
228 			j = (j - 1) / 2;  in eytzinger0_sort_r()
229 			eytzinger0_do_swap(base, n, size, swap_func, priv, j, k);  in eytzinger0_sort_r()
260 		return -1;
303 	return -1;