Re: coccinelle: adjustments for array.cocci?

Am 12.11.19 um 16:08 schrieb Markus Elfring:

Hello,

I would like to comment implementation details from
the commit 177fbab747da4f58cb2a8ce010b3515c86dd67c9 ("coccinelle: use COPY_ARRAY for copying arrays").


Do you find the following code variant (for the semantic patch language) also useful?

 memcpy(
(       ptr, E, n *
-       sizeof(*(ptr))
+       sizeof(T)
|       arr, E, n *
-       sizeof(*(arr))
+       sizeof(T)
|       E, ptr, n *
-       sizeof(*(ptr))
+       sizeof(T)
|       E, arr, n *
-       sizeof(*(arr))
+       sizeof(T)
)
       )

This reduces duplication in the semantic patch, which is nice.  I think
I tried something like that at the time, but found that it failed to
produce some of the cases in 921d49be86 ("use COPY_ARRAY for copying
arrays", 2019-06-15) for some reason.

How do you think about the following SmPL code variant?

-memcpy
+COPY_ARRAY
       (
(       dst_ptr
|       dst_arr
)
       ,
(       src_ptr
|       src_arr
)
       ,
-       (n) * sizeof(T)
+       n
       )

This eliminates duplication in the semantic patch, which is good.  It
messes up the indentation of n in some of the cases in 921d49be86 ("use
COPY_ARRAY for copying arrays", 2019-06-15), though.  Hmm, but that can
be cured by duplicating the comma:

   - , (n) * sizeof(T)
   + , n

René