[PATCH][tree-ssa-loop-ch] Add missing NULL test for dump_file

[PATCH][tree-ssa-loop-ch] Add missing NULL test for dump_file

[Tom de Vries]

Hi,

If we change gimple_can_duplicate_bb_p to return false instead of true, we run
into a segfault in ch_base::copy_headers due to using dump_file while it's
NULL:
...
      if (!gimple_duplicate_sese_region (entry, exit, bbs, n_bbs, copied_bbs,
                                        true))
       {
         fprintf (dump_file, "Duplication failed.\n");
         continue;
       }
...

Fix this by adding the missing dump_file != NULL test.

Tested by rebuilding lto1 and rerunning the failing test-case.

[ Not committing this as obvious because I'm not sure about the
(dump_flags & TDF_DETAILS) bit. ]

OK for trunk?

Thanks,
- Tom

[tree-ssa-loop-ch] Add missing NULL test for dump_file

gcc/ChangeLog:

2020-10-07  Tom de Vries  <tdevries@suse.de>

	* tree-ssa-loop-ch.c (ch_base::copy_headers): Add missing NULL test
	for dump_file.

---
 gcc/tree-ssa-loop-ch.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gcc/tree-ssa-loop-ch.c b/gcc/tree-ssa-loop-ch.c
index b86acf7c39d..1f3d9321a55 100644
--- a/gcc/tree-ssa-loop-ch.c
+++ b/gcc/tree-ssa-loop-ch.c
@@ -425,7 +425,8 @@ ch_base::copy_headers (function *fun)
       if (!gimple_duplicate_sese_region (entry, exit, bbs, n_bbs, copied_bbs,
 					 true))
 	{
-	  fprintf (dump_file, "Duplication failed.\n");
+	  if (dump_file && (dump_flags & TDF_DETAILS))
+	    fprintf (dump_file, "Duplication failed.\n");
 	  continue;
 	}
       copied.safe_push (std::make_pair (entry, loop));

Re: [PATCH][tree-ssa-loop-ch] Add missing NULL test for dump_file

[Richard Biener]

On Wed, 7 Oct 2020, Tom de Vries wrote:

> Hi,
> 
> If we change gimple_can_duplicate_bb_p to return false instead of true, we run
> into a segfault in ch_base::copy_headers due to using dump_file while it's
> NULL:
> ...
>       if (!gimple_duplicate_sese_region (entry, exit, bbs, n_bbs, copied_bbs,
>                                         true))
>        {
>          fprintf (dump_file, "Duplication failed.\n");
>          continue;
>        }
> ...
> 
> Fix this by adding the missing dump_file != NULL test.
> 
> Tested by rebuilding lto1 and rerunning the failing test-case.
> 
> [ Not committing this as obvious because I'm not sure about the
> (dump_flags & TDF_DETAILS) bit. ]
> 
> OK for trunk?

OK.

Richard.

> Thanks,
> - Tom
> 
> [tree-ssa-loop-ch] Add missing NULL test for dump_file
> 
> gcc/ChangeLog:
> 
> 2020-10-07  Tom de Vries  <tdevries@suse.de>
> 
> 	* tree-ssa-loop-ch.c (ch_base::copy_headers): Add missing NULL test
> 	for dump_file.
> 
> ---
>  gcc/tree-ssa-loop-ch.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/gcc/tree-ssa-loop-ch.c b/gcc/tree-ssa-loop-ch.c
> index b86acf7c39d..1f3d9321a55 100644
> --- a/gcc/tree-ssa-loop-ch.c
> +++ b/gcc/tree-ssa-loop-ch.c
> @@ -425,7 +425,8 @@ ch_base::copy_headers (function *fun)
>        if (!gimple_duplicate_sese_region (entry, exit, bbs, n_bbs, copied_bbs,
>  					 true))
>  	{
> -	  fprintf (dump_file, "Duplication failed.\n");
> +	  if (dump_file && (dump_flags & TDF_DETAILS))
> +	    fprintf (dump_file, "Duplication failed.\n");
>  	  continue;
>  	}
>        copied.safe_push (std::make_pair (entry, loop));
> 

-- 
Richard Biener <rguenther@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imend