Re: coccinelle: adjustments for array.cocci?

From: Markus Elfring <markus.elfring@web.de>
Date: Nov 16, 2019, 16:33 UTC
Message-ID: <05ab1110-2115-7886-f890-9983caabc52c@web.de>
In-Reply-To: <5189f847-1af1-f050-6c72-576a977f6f12@web.de>

> 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.

I propose to integrate an other solution variant.

* How do you think about to delete questionable transformation rules
  together with increasing the usage of nested disjunctions in this script
  for the semantic patch language?

* Can a single transformation rule become sufficient for the discussed
  change pattern?

@@
type T;
T* dst_ptr, src_ptr, ptr;
T[] dst_arr, src_arr;
expression n, x;
@@
(
-memcpy
+COPY_ARRAY
       (
(       dst_ptr
|       dst_arr
)
       ,
(       src_ptr
|       src_arr
)
-      , (n) * \( sizeof(T) \| sizeof( \( *(x) \| x[...] \) ) \)
+      , n
       )
|
-memmove
+MOVE_ARRAY
        (dst_ptr,
         src_ptr
-               , (n) * \( sizeof(* \( dst_ptr \| src_ptr \) ) \| sizeof(T) \)
+               , n
        )
|
-ptr = xmalloc((n) * \( sizeof(*ptr) \| sizeof(T) \))
+ALLOC_ARRAY(ptr, n)
)

Would you like to clarify remaining challenges for pretty-printing in such use cases?

Regards, Markus