[PATCH] coccinelle: improve array.cocci

[Markus Elfring <Markus.Elfring@xxxxxx>]

From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Mon, 18 Nov 2019 17:00:37 +0100

This script contained transformation rules for the semantic patch language
which used similar code.

1. Delete two SmPL rules which were used to transform source code fragments
   (pointer expressions) so that the search pattern “sizeof(T)” would work
   in the third rule.
   See also the topic “coccinelle: adjustments for array.cocci?”:
   https://public-inbox.org/git/f28f5fb8-2814-9df5-faf2-7146ed1a1f4d@xxxxxx/

2. Combine the remaining rules by using six SmPL disjunctions.

3. Adjust case distinctions and corresponding metavariables so that
   the desired search for update candidates can be more complete.

4. Increase the precision for the specification of required changes.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
 contrib/coccinelle/array.cocci | 100 ++++++---------------------------
 1 file changed, 18 insertions(+), 82 deletions(-)

diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci
index 46b8d2ee11..bcd6ff4793 100644
--- a/contrib/coccinelle/array.cocci
+++ b/contrib/coccinelle/array.cocci
@@ -1,90 +1,26 @@
-@@
-expression dst, src, n, E;
-@@
-  memcpy(dst, src, n * sizeof(
-- E[...]
-+ *(E)
-  ))
-
 @@
 type T;
-T *ptr;
-T[] arr;
-expression E, n;
-@@
-(
-  memcpy(ptr, E,
-- n * sizeof(*(ptr))
-+ n * sizeof(T)
-  )
-|
-  memcpy(arr, E,
-- n * sizeof(*(arr))
-+ n * sizeof(T)
-  )
-|
-  memcpy(E, ptr,
-- n * sizeof(*(ptr))
-+ n * sizeof(T)
-  )
-|
-  memcpy(E, arr,
-- n * sizeof(*(arr))
-+ n * sizeof(T)
-  )
-)
-
-@@
-type T;
-T *dst_ptr;
-T *src_ptr;
-T[] dst_arr;
 T[] src_arr;
-expression n;
+expression n, dst_e, src_e;
+expression* dst_p_e, src_p_e;
 @@
 (
-- memcpy(dst_ptr, src_ptr, (n) * sizeof(T))
-+ COPY_ARRAY(dst_ptr, src_ptr, n)
-|
-- memcpy(dst_ptr, src_arr, (n) * sizeof(T))
-+ COPY_ARRAY(dst_ptr, src_arr, n)
-|
-- memcpy(dst_arr, src_ptr, (n) * sizeof(T))
-+ COPY_ARRAY(dst_arr, src_ptr, n)
-|
-- memcpy(dst_arr, src_arr, (n) * sizeof(T))
-+ COPY_ARRAY(dst_arr, src_arr, n)
-)
-
-@@
-type T;
-T *dst;
-T *src;
-expression n;
-@@
 (
-- memmove(dst, src, (n) * sizeof(*dst));
-+ MOVE_ARRAY(dst, src, n);
-|
-- memmove(dst, src, (n) * sizeof(*src));
-+ MOVE_ARRAY(dst, src, n);
+-memcpy
++COPY_ARRAY
 |
-- memmove(dst, src, (n) * sizeof(T));
-+ MOVE_ARRAY(dst, src, n);
+-memmove
++MOVE_ARRAY
+)
+       (
+        dst_e,
+        src_e
+-       , (n) * \( sizeof(T) \| sizeof( \( *(src_p_e) \| src_e[...] \| src_arr \) ) \)
++       , n
+       )
+|
++ALLOC_ARRAY(
+             dst_p_e
+-                    = xmalloc((n) * \( sizeof( \( *(src_p_e) \| src_e[...] \| src_arr \) ) \| sizeof(T) \))
++            , n)
 )
-
-@@
-type T;
-T *ptr;
-expression n;
-@@
-- ptr = xmalloc((n) * sizeof(*ptr));
-+ ALLOC_ARRAY(ptr, n);
-
-@@
-type T;
-T *ptr;
-expression n;
-@@
-- ptr = xmalloc((n) * sizeof(T));
-+ ALLOC_ARRAY(ptr, n);
--
2.24.0