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[PATCH 1/2] bitops.h: Improve sign_extend32()'s documentation

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It is often overlooked that sign_extend32(), despite it's name, is safe
to use for 16 and 8 bit types aswell. This should help that sign extension
isn't done manually some other way.

Signed-off-by: Martin Kepplinger <martin.kepplinger@theobroma-systems.com>
---
 include/linux/bitops.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index e635533..2177c01 100644
--- 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 aswell.
  */
 static inline __s32 sign_extend32(__u32 value, int index)
 {
-- 
2.1.4

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bitops.h: improve sign extending API Martin Kepplinger <martink@posteo.de> - 2015-10-15 18:30 +0200
  [PATCH 2/2] bitops.h: add sign_extend64() Martin Kepplinger <martink@posteo.de> - 2015-10-15 18:30 +0200
  [PATCH 1/2] bitops.h: Improve sign_extend32()'s documentation Martin Kepplinger <martink@posteo.de> - 2015-10-15 18:30 +0200
    Re: [PATCH 1/2] bitops.h: Improve sign_extend32()'s documentation "George Spelvin" <linux@horizon.com> - 2015-10-15 20:10 +0200

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