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-rw-r--r--lib/hweight.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/lib/hweight.c b/lib/hweight.c
index 389424ecb129..63ee4eb1228d 100644
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -11,11 +11,18 @@
11 11
12unsigned int hweight32(unsigned int w) 12unsigned int 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(hweight32);
21 28