On Wed, 18 Oct 2023, Simone Ballarin wrote:
Add const and pure attributes to address reports
of MISRA C:2012 Rule 13.1: Initializer lists shall
not contain persistent side effects
Add pure attribute to function pdx_to_pfn.
Add const attribute to functions generated by TYPE_SAFE.
These functions are used in initializer lists: adding
the attributes ensures that no effect will be performed
by them.
Signed-off-by: Simone Ballarin <simone.ballarin@xxxxxxxxxxx>
Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
However one comment below...
---
Function attributes pure and const do not need to be added as GCC
attributes, they can be added using ECLAIR configurations.
---
xen/include/xen/pdx.h | 2 +-
xen/include/xen/typesafe.h | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/xen/include/xen/pdx.h b/xen/include/xen/pdx.h
index f3fbc4273a..5d1050967a 100644
--- a/xen/include/xen/pdx.h
+++ b/xen/include/xen/pdx.h
@@ -164,7 +164,7 @@ static inline unsigned long pfn_to_pdx(unsigned long pfn)
* @param pdx Page index
* @return Obtained pfn after decompressing the pdx
*/
-static inline unsigned long pdx_to_pfn(unsigned long pdx)
+static inline __attribute_pure__ unsigned long pdx_to_pfn(unsigned long pdx)
{
return (pdx & pfn_pdx_bottom_mask) |
((pdx << pfn_pdx_hole_shift) & pfn_top_mask);
diff --git a/xen/include/xen/typesafe.h b/xen/include/xen/typesafe.h
index 7ecd3b4a8d..615df6f944 100644
--- a/xen/include/xen/typesafe.h
+++ b/xen/include/xen/typesafe.h
@@ -21,8 +21,8 @@
#define TYPE_SAFE(_type, _name) \
typedef struct { _type _name; } _name##_t; \
- static inline _name##_t _##_name(_type n) { return (_name##_t) { n }; } \
- static inline _type _name##_x(_name##_t n) { return n._name; }
+ static inline __attribute_const__ _name##_t _##_name(_type n) { return
(_name##_t) { n }; } \
+ static inline __attribute_const__ _type _name##_x(_name##_t n) { return
n._name; }
#else
I think we should also add __attribute_const__ in the NDEBUG definitions
just below.
