Merge branch 'parisc-4.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...

[firefly-linux-kernel-4.4.55.git] / include / linux / bitops.h

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index e63553386ae715d387fadd39c4e53650ce3e226e..2b8ed123ad36b26bc26956293452937d3ac1b90e 100644 (file)
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -164,6 +164,8 @@ static inline __u8 ror8(__u8 word, unsigned int 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
+ *
+ * This is safe to use for 16- and 8-bit types as well.
  */
 static inline __s32 sign_extend32(__u32 value, int index)
 {
@@ -171,6 +173,17 @@ static inline __s32 sign_extend32(__u32 value, int index)
        return (__s32)(value << shift) >> shift;
 }
 
+/**
+ * sign_extend64 - sign extend a 64-bit value using specified bit as sign-bit
+ * @value: value to sign extend
+ * @index: 0 based bit index (0<=index<64) to sign bit
+ */
+static inline __s64 sign_extend64(__u64 value, int index)
+{
+       __u8 shift = 63 - index;
+       return (__s64)(value << shift) >> shift;
+}
+
 static inline unsigned fls_long(unsigned long l)
 {
        if (sizeof(l) == 4)