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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2011-01-31 21:16:22 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2011-01-31 21:16:22 -0800
commita1f3d4bba8ea395a39d34ade6017afee8be16031 (patch)
tree874d843d35622f17aa6c3e048e42cf0d679bcb75 /include/linux/bitops.h
parent723d928417bffff6467da155d8ebbbe016464012 (diff)
parentebf53826e105f488f4f628703a108e98940d1dc5 (diff)
Merge commit 'v2.6.38-rc3' into next
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h11
1 files changed, 11 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 827cc95711ef..2184c6b97aeb 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -109,6 +109,17 @@ static inline __u8 ror8(__u8 word, unsigned int shift)
return (word >> shift) | (word << (8 - shift));
}
+/**
+ * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
+ * @value: value to sign extend
+ * @index: 0 based bit index (0<=index<32) to sign bit
+ */
+static inline __s32 sign_extend32(__u32 value, int index)
+{
+ __u8 shift = 31 - index;
+ return (__s32)(value << shift) >> shift;
+}
+
static inline unsigned fls_long(unsigned long l)
{
if (sizeof(l) == 4)