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-rw-r--r--lib/hweight.c26
1 files changed, 17 insertions, 9 deletions
diff --git a/lib/hweight.c b/lib/hweight.c
index 389424ecb129..3c79d50814cf 100644
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -9,37 +9,45 @@
9 * The Hamming Weight of a number is the total number of bits set in it. 9 * The Hamming Weight of a number is the total number of bits set in it.
10 */ 10 */
11 11
12unsigned int hweight32(unsigned int w) 12unsigned int __sw_hweight32(unsigned int w)
13{ 13{
14#ifdef ARCH_HAS_FAST_MULTIPLIER
15 w -= (w >> 1) & 0x55555555;
16 w = (w & 0x33333333) + ((w >> 2) & 0x33333333);
17 w = (w + (w >> 4)) & 0x0f0f0f0f;
18 return (w * 0x01010101) >> 24;
19#else
14 unsigned int res = w - ((w >> 1) & 0x55555555); 20 unsigned int res = w - ((w >> 1) & 0x55555555);
15 res = (res & 0x33333333) + ((res >> 2) & 0x33333333); 21 res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
16 res = (res + (res >> 4)) & 0x0F0F0F0F; 22 res = (res + (res >> 4)) & 0x0F0F0F0F;
17 res = res + (res >> 8); 23 res = res + (res >> 8);
18 return (res + (res >> 16)) & 0x000000FF; 24 return (res + (res >> 16)) & 0x000000FF;
25#endif
19} 26}
20EXPORT_SYMBOL(hweight32); 27EXPORT_SYMBOL(__sw_hweight32);
21 28
22unsigned int hweight16(unsigned int w) 29unsigned int __sw_hweight16(unsigned int w)
23{ 30{
24 unsigned int res = w - ((w >> 1) & 0x5555); 31 unsigned int res = w - ((w >> 1) & 0x5555);
25 res = (res & 0x3333) + ((res >> 2) & 0x3333); 32 res = (res & 0x3333) + ((res >> 2) & 0x3333);
26 res = (res + (res >> 4)) & 0x0F0F; 33 res = (res + (res >> 4)) & 0x0F0F;
27 return (res + (res >> 8)) & 0x00FF; 34 return (res + (res >> 8)) & 0x00FF;
28} 35}
29EXPORT_SYMBOL(hweight16); 36EXPORT_SYMBOL(__sw_hweight16);
30 37
31unsigned int hweight8(unsigned int w) 38unsigned int __sw_hweight8(unsigned int w)
32{ 39{
33 unsigned int res = w - ((w >> 1) & 0x55); 40 unsigned int res = w - ((w >> 1) & 0x55);
34 res = (res & 0x33) + ((res >> 2) & 0x33); 41 res = (res & 0x33) + ((res >> 2) & 0x33);
35 return (res + (res >> 4)) & 0x0F; 42 return (res + (res >> 4)) & 0x0F;
36} 43}
37EXPORT_SYMBOL(hweight8); 44EXPORT_SYMBOL(__sw_hweight8);
38 45
39unsigned long hweight64(__u64 w) 46unsigned long __sw_hweight64(__u64 w)
40{ 47{
41#if BITS_PER_LONG == 32 48#if BITS_PER_LONG == 32
42 return hweight32((unsigned int)(w >> 32)) + hweight32((unsigned int)w); 49 return __sw_hweight32((unsigned int)(w >> 32)) +
50 __sw_hweight32((unsigned int)w);
43#elif BITS_PER_LONG == 64 51#elif BITS_PER_LONG == 64
44#ifdef ARCH_HAS_FAST_MULTIPLIER 52#ifdef ARCH_HAS_FAST_MULTIPLIER
45 w -= (w >> 1) & 0x5555555555555555ul; 53 w -= (w >> 1) & 0x5555555555555555ul;
@@ -56,4 +64,4 @@ unsigned long hweight64(__u64 w)
56#endif 64#endif
57#endif 65#endif
58} 66}
59EXPORT_SYMBOL(hweight64); 67EXPORT_SYMBOL(__sw_hweight64);