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Re: [Cocci] git-coccinelle: adjustments for array.cocci?

From
JLJulia Lawall <julia.lawall@lip6.fr>
Date
Nov 16, 2019, 17:57 UTC
Message-ID
<alpine.DEB.2.21.1911161855400.3558@hadrien>
In-Reply-To
<6fffd13a-738b-e750-9f5a-f0bfb252855b@web.de>
On Fri, 15 Nov 2019, Markus Elfring wrote:
Show 68 quoted lines
> > Anyway, someone who can reproduce the issue using the latest release
> > of Coccinelle would be in a better position to file a bug report.
>
> Hello,
>
> I repeated the discussed source code transformation approach together
> with the software combination “Coccinelle 1.0.8-00004-g842075f7” (OCaml 4.09).
> https://github.com/coccinelle/coccinelle/commits/master
>
> 1. Yesterday I checked the source files out for the software “Git”
>    according to the commit “The first batch post 2.24 cycle”.
>    https://github.com/git/git/commit/d9f6f3b6195a0ca35642561e530798ad1469bd41
>
> 2. I restored a previous development status by the following command.
>
>    git show 921d49be86 | patch -p1 -R
>
>    See also:
>    https://public-inbox.org/git/53346d52-e096-c651-f70a-ce6ca4d82ff9@web.de/
>
> 3. I stored a generated patch based on the currently released SmPL script.
>    https://github.com/git/git/blob/177fbab747da4f58cb2a8ce010b3515c86dd67c9/contrib/coccinelle/array.cocci
>
> 4. I applied the following patch then.
>
> diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci
> index 46b8d2ee11..89df184bbd 100644
> --- a/contrib/coccinelle/array.cocci
> +++ b/contrib/coccinelle/array.cocci
> @@ -12,27 +12,21 @@ 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)
> -  )
> + 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 seems quite unreadable, in contrast to the original code.
Show 7 quoted lines
>
>  @@
>  type T;
>
>    I suggested in this way to move a bit of SmPL code.
>
> 5. I stored another generated patch based on the adjusted SmPL script.
No idea what it means to store a patch.
Show 13 quoted lines
> 6. I performed a corresponding file comparison.
>
> --- array-released.diff	2019-11-14 21:29:11.020576916 +0100
> +++ array-reduced1.diff	2019-11-14 21:45:58.931956527 +0100
> @@ -6,24 +6,10 @@
>   	r->entry_count = t->entry_count;
>   	r->delta_depth = t->delta_depth;
>  -	memcpy(r->entries,t->entries,t->entry_count*sizeof(t->entries[0]));
> -+	COPY_ARRAY(r->entries, t->entries, t->entry_count);
> ++	memcpy(r->entries,t->entries,t->entry_count*sizeof(*(t->entries)));
>   	release_tree_content(t);
>   	return r;
>   }

I have no idea what is being compared here. The COPY_ARRAY thing looks nice, but doesn't seem to have anything to do with your semantic patch.

julia
Show 46 quoted lines
> -diff -u -p a/pretty.c b/pretty.c
> ---- a/pretty.c
> -+++ b/pretty.c
> -@@ -106,8 +106,8 @@ static void setup_commit_formats(void)
> - 	commit_formats_len = ARRAY_SIZE(builtin_formats);
> - 	builtin_formats_len = commit_formats_len;
> - 	ALLOC_GROW(commit_formats, commit_formats_len, commit_formats_alloc);
> --	memcpy(commit_formats, builtin_formats,
> --	       sizeof(*builtin_formats)*ARRAY_SIZE(builtin_formats));
> -+	COPY_ARRAY(commit_formats, builtin_formats,
> -+		   ARRAY_SIZE(builtin_formats));
> -
> - 	git_config(git_pretty_formats_config, NULL);
> - }
>  diff -u -p a/packfile.c b/packfile.c
>  --- a/packfile.c
>  +++ b/packfile.c
> @@ -36,17 +22,6 @@
>   		} else {
>   			ALLOC_GROW(poi_stack, poi_stack_nr+1, poi_stack_alloc);
>   		}
> -@@ -1698,8 +1698,8 @@ void *unpack_entry(struct repository *r,
> - 		    && delta_stack == small_delta_stack) {
> - 			delta_stack_alloc = alloc_nr(delta_stack_nr);
> - 			ALLOC_ARRAY(delta_stack, delta_stack_alloc);
> --			memcpy(delta_stack, small_delta_stack,
> --			       sizeof(*delta_stack)*delta_stack_nr);
> -+			COPY_ARRAY(delta_stack, small_delta_stack,
> -+				   delta_stack_nr);
> - 		} else {
> - 			ALLOC_GROW(delta_stack, delta_stack_nr+1, delta_stack_alloc);
> - 		}
>  diff -u -p a/compat/regex/regexec.c b/compat/regex/regexec.c
>  --- a/compat/regex/regexec.c
>  +++ b/compat/regex/regexec.c
>
>
> How do you think about the differences from this test result?
>
> Regards,
> Markus
> _______________________________________________
> Cocci mailing list
> Cocci@systeme.lip6.fr
> https://systeme.lip6.fr/mailman/listinfo/cocci
>
Previous: Markus ElfringNext: Markus Elfring
Message 16 of 41 in “coccinelle: adjustments for array.cocci?”
  1. Markus ElfringNov 12, 2019
  2. René ScharfeNov 12, 2019
  3. Junio C HamanoNov 13, 2019
  4. Markus ElfringNov 13, 2019
  5. Junio C HamanoNov 14, 2019
  6. Markus ElfringNov 14, 2019
  7. René ScharfeNov 14, 2019
  8. Markus ElfringNov 14, 2019
  9. René ScharfeNov 14, 2019
  10. Markus ElfringNov 15, 2019
  11. Markus ElfringNov 15, 2019
  12. Markus ElfringNov 15, 2019
  13. Julia LawallNov 16, 2019
  14. Markus ElfringNov 16, 2019
  15. Markus ElfringNov 16, 2019
  16. Julia LawallNov 16, 2019
  17. Markus ElfringNov 16, 2019
  18. Markus ElfringNov 15, 2019
  19. René ScharfeNov 16, 2019
  20. Markus ElfringNov 17, 2019
  21. René ScharfeNov 17, 2019
  22. Markus ElfringNov 17, 2019
  23. René ScharfeNov 19, 2019
  24. Markus ElfringNov 19, 2019
  25. René ScharfeNov 21, 2019
  26. Markus ElfringNov 16, 2019
  27. René ScharfeNov 16, 2019
  28. Markus ElfringNov 17, 2019
  29. René ScharfeNov 17, 2019
  30. Markus ElfringNov 17, 2019
  31. René ScharfeNov 19, 2019
  32. coccinelle: improve array.cocciMarkus Elfring, Nov 18, 2019
  33. René ScharfeNov 19, 2019
  34. Markus ElfringNov 20, 2019
  35. René ScharfeNov 21, 2019
  36. Markus ElfringNov 21, 2019
  37. SZEDER GáborNov 22, 2019
  38. Markus ElfringNov 22, 2019
  39. Junio C HamanoNov 22, 2019
  40. Markus ElfringNov 22, 2019
  41. Markus ElfringJan 25, 2020

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