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-rw-r--r--include/linux/bitops.h131
1 files changed, 8 insertions, 123 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 208650b1ad3..5d1eabcde5d 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -3,88 +3,11 @@
#include <asm/types.h>
/*
- * ffs: find first bit set. This is defined the same way as
- * the libc and compiler builtin ffs routines, therefore
- * differs in spirit from the above ffz (man ffs).
- */
-
-static inline int generic_ffs(int x)
-{
- int r = 1;
-
- if (!x)
- return 0;
- if (!(x & 0xffff)) {
- x >>= 16;
- r += 16;
- }
- if (!(x & 0xff)) {
- x >>= 8;
- r += 8;
- }
- if (!(x & 0xf)) {
- x >>= 4;
- r += 4;
- }
- if (!(x & 3)) {
- x >>= 2;
- r += 2;
- }
- if (!(x & 1)) {
- x >>= 1;
- r += 1;
- }
- return r;
-}
-
-/*
- * fls: find last bit set.
- */
-
-static __inline__ int generic_fls(int x)
-{
- int r = 32;
-
- if (!x)
- return 0;
- if (!(x & 0xffff0000u)) {
- x <<= 16;
- r -= 16;
- }
- if (!(x & 0xff000000u)) {
- x <<= 8;
- r -= 8;
- }
- if (!(x & 0xf0000000u)) {
- x <<= 4;
- r -= 4;
- }
- if (!(x & 0xc0000000u)) {
- x <<= 2;
- r -= 2;
- }
- if (!(x & 0x80000000u)) {
- x <<= 1;
- r -= 1;
- }
- return r;
-}
-
-/*
* Include this here because some architectures need generic_ffs/fls in
* scope
*/
#include <asm/bitops.h>
-
-static inline int generic_fls64(__u64 x)
-{
- __u32 h = x >> 32;
- if (h)
- return fls(h) + 32;
- return fls(x);
-}
-
static __inline__ int get_bitmask_order(unsigned int count)
{
int order;
@@ -103,54 +26,9 @@ static __inline__ int get_count_order(unsigned int count)
return order;
}
-/*
- * hweightN: returns the hamming weight (i.e. the number
- * of bits set) of a N-bit word
- */
-
-static inline unsigned int generic_hweight32(unsigned int w)
-{
- unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
- res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
- res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
- res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
- return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
-}
-
-static inline unsigned int generic_hweight16(unsigned int w)
-{
- unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
- res = (res & 0x3333) + ((res >> 2) & 0x3333);
- res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
- return (res & 0x00FF) + ((res >> 8) & 0x00FF);
-}
-
-static inline unsigned int generic_hweight8(unsigned int w)
-{
- unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
- res = (res & 0x33) + ((res >> 2) & 0x33);
- return (res & 0x0F) + ((res >> 4) & 0x0F);
-}
-
-static inline unsigned long generic_hweight64(__u64 w)
-{
-#if BITS_PER_LONG < 64
- return generic_hweight32((unsigned int)(w >> 32)) +
- generic_hweight32((unsigned int)w);
-#else
- u64 res;
- res = (w & 0x5555555555555555ul) + ((w >> 1) & 0x5555555555555555ul);
- res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);
- res = (res & 0x0F0F0F0F0F0F0F0Ful) + ((res >> 4) & 0x0F0F0F0F0F0F0F0Ful);
- res = (res & 0x00FF00FF00FF00FFul) + ((res >> 8) & 0x00FF00FF00FF00FFul);
- res = (res & 0x0000FFFF0000FFFFul) + ((res >> 16) & 0x0000FFFF0000FFFFul);
- return (res & 0x00000000FFFFFFFFul) + ((res >> 32) & 0x00000000FFFFFFFFul);
-#endif
-}
-
static inline unsigned long hweight_long(unsigned long w)
{
- return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w);
+ return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
}
/*
@@ -175,4 +53,11 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
return (word >> shift) | (word << (32 - shift));
}
+static inline unsigned fls_long(unsigned long l)
+{
+ if (sizeof(l) == 4)
+ return fls(l);
+ return fls64(l);
+}
+
#endif