This patch defines constant_fls() instead of removed generic_fls().
Signed-off-by: Akinobu Mita <[email protected]>
Cc: Russell King <[email protected]>
include/asm-arm/bitops.h | 31 ++++++++++++++++++++++++++++++-
1 files changed, 30 insertions(+), 1 deletion(-)
Index: 2.6-mm/include/asm-arm/bitops.h
===================================================================
--- 2.6-mm.orig/include/asm-arm/bitops.h
+++ 2.6-mm/include/asm-arm/bitops.h
@@ -239,13 +239,42 @@ extern int _find_next_bit_be(const unsig
#else
+static inline int constant_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;
+}
+
/*
* On ARMv5 and above those functions can be implemented around
* the clz instruction for much better code efficiency.
*/
#define fls(x) \
- ( __builtin_constant_p(x) ? generic_fls(x) : \
+ ( __builtin_constant_p(x) ? constant_fls(x) : \
({ int __r; asm("clz\t%0, %1" : "=r"(__r) : "r"(x) : "cc"); 32-__r; }) )
#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
#define __ffs(x) (ffs(x) - 1)
--
-
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