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[PATCH] FRV: Fix fls() to handle bit 31 being set correctly

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Fix FRV fls() to handle bit 31 being set correctly (it should return 32 not 0).

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
David Howells 2006-09-25 23:32:07 -07:00 committed by Linus Torvalds
parent af8c65b57a
commit 92fc707208
1 changed files with 17 additions and 4 deletions
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21
include/asm-frv/bitops.h
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@ -161,16 +161,29 @@ static inline int __test_bit(int nr, const volatile void * addr)
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/find.h>
/*
* fls: find last bit set.
/**
* fls - find last bit set
* @x: the word to search
*
* This is defined the same way as ffs:
* - return 32..1 to indicate bit 31..0 most significant bit set
* - return 0 to indicate no bits set
*/
#define fls(x) \
({ \
int bit; \
\
asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x)); \
asm(" subcc %1,gr0,gr0,icc0 \n" \
" ckne icc0,cc4 \n" \
" cscan.p %1,gr0,%0 ,cc4,#1 \n" \
" csub %0,%0,%0 ,cc4,#0 \n" \
" csub %2,%0,%0 ,cc4,#1 \n" \
: "=&r"(bit) \
: "r"(x), "r"(32) \
: "icc0", "cc4" \
); \
\
bit ? 33 - bit : bit; \
bit; \
})
#include <asm-generic/bitops/fls64.h>