Re: [PATCH] ipa/97346 - fix leak of reference_vars_to_consider

[Jan Hubicka]

> This cleans up allocation/deallocation of reference_vars_to_consider,
> specifically always releasing the vector allocated in ipa_init and
> also making sure to release it before re-allocating it in
> ipa_reference_write_optimization_summary.
> 
> Bootstrapped and tested on x86_64-unknown-linux-gnu, OK?
> 
> Thanks,
> Richard.
> 
> 2021-02-10  Richard Biener  <rguent...@suse.de>
> 
>       PR ipa/97346
>       * ipa-reference.c (propagate): Always free
>       reference_vars_to_consider.
>       (ipa_reference_write_optimization_summary): Free
>       reference_vars_to_consider before re-allocating it.
>       (ipa_reference_write_optimization_summary): Use vec_free
>       and NULL reference_vars_to_consider.

Hi,
this is version I commited after discussion on the PR
(it makes it more explicit that reference_vars_to_consider are used
during analysis only to aid dumping).

Honza


2021-02-14  Jan Hubicka  <hubi...@ucw.cz>
            Richard Biener  <rguet...@suse.de>

        PR ipa/97346
        * ipa-reference.c (ipa_init): Only conditinally initialize
        reference_vars_to_consider.
        (propagate): Conditionally deninitialize reference_vars_to_consider.
        (ipa_reference_write_optimization_summary): Sanity check that
        reference_vars_to_consider is not allocated.

diff --git a/gcc/ipa-reference.c b/gcc/ipa-reference.c
index 2ea2a6d5327..6cf78ff94a6 100644
--- a/gcc/ipa-reference.c
+++ b/gcc/ipa-reference.c
@@ -458,8 +458,8 @@ ipa_init (void)
 
   ipa_init_p = true;
 
-  vec_alloc (reference_vars_to_consider, 10);
-
+  if (dump_file)
+    vec_alloc (reference_vars_to_consider, 10);
 
   if (ipa_ref_opt_sum_summaries != NULL)
     {
@@ -967,8 +967,12 @@ propagate (void)
     }
 
   if (dump_file)
-    vec_free (reference_vars_to_consider);
-  reference_vars_to_consider = NULL;
+    {
+      vec_free (reference_vars_to_consider);
+      reference_vars_to_consider = NULL;
+    }
+  else
+    gcc_checking_assert (!reference_vars_to_consider);
   return remove_p ? TODO_remove_functions : 0;
 }
 
@@ -1059,6 +1063,7 @@ ipa_reference_write_optimization_summary (void)
   auto_bitmap ltrans_statics;
   int i;
 
+  gcc_checking_assert (!reference_vars_to_consider);
   vec_alloc (reference_vars_to_consider, ipa_reference_vars_uids);
   reference_vars_to_consider->safe_grow (ipa_reference_vars_uids, true);
 
@@ -1117,7 +1122,8 @@ ipa_reference_write_optimization_summary (void)
          }
       }
   lto_destroy_simple_output_block (ob);
-  delete reference_vars_to_consider;
+  vec_free (reference_vars_to_consider);
+  reference_vars_to_consider = NULL;
 }
 
 /* Deserialize the ipa info for lto.  */