[dpdk-dev] [PATCH v6 1/6] lib/eal: implement the family of rte bit operation APIs

[Stephen Hemminger]

On Sat, 21 Dec 2019 16:07:23 +0000
Honnappa Nagarahalli <Honnappa.Nagarahalli at arm.com> wrote:

> Converting these into macros will help remove the size based duplication of APIs. I came up with the following macro:
> 
> #define RTE_GET_BIT(nr, var, ret, memorder) \
> ({ \
>     if (sizeof(var) == sizeof(uint32_t)) { \
>         uint32_t mask1 = 1U << (nr)%32; \
>         ret = __atomic_load_n(&var, (memorder)) & mask1;\
>     } \
>     else {\
>         uint64_t mask2 = 1UL << (nr)%64;\
>         ret = __atomic_load_n(&var, (memorder)) & mask2;\
>     } \
> })


Follow on if you want to do it as macros, then use typeof() to make the
mask any size.