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| author | David Howells <dhowells@redhat.com> | 2006-09-25 23:32:07 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 08:48:53 -0700 |
| commit | 92fc707208bb2e601c24b5ab65db37bcb361b658 (patch) | |
| tree | a0b2d56c30ade74946e9edd74f2d516f475c68f5 | |
| parent | af8c65b57aaa4ae321af34dbfc5ca7f5625263fe (diff) | |
| download | linux-3.10-92fc707208bb2e601c24b5ab65db37bcb361b658.tar.gz linux-3.10-92fc707208bb2e601c24b5ab65db37bcb361b658.tar.bz2 linux-3.10-92fc707208bb2e601c24b5ab65db37bcb361b658.zip | |
[PATCH] FRV: Fix fls() to handle bit 31 being set correctly
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>
| -rw-r--r-- | include/asm-frv/bitops.h | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/include/asm-frv/bitops.h b/include/asm-frv/bitops.h index 980ae1b0cd2..97fb746f76c 100644 --- a/include/asm-frv/bitops.h +++ b/include/asm-frv/bitops.h @@ -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> |