[2/5] Existing call graph infrastructure enhancement

On 09/24/2014 05:01 PM, Jan Hubicka wrote:
>> Hi.
>>
>> Following patch enhances API functions to be ready for main patch of this patchset.
>>
>> Ready for thunk?
>>
>> Thank you,
>> Martin
>
>> gcc/ChangeLog:
>>
>> 2014-09-21  Martin Liška  <mliska@suse.cz>
>>
>> 	* cgraph.c (cgraph_node::release_body): New argument keep_arguments
>> 	introduced.
>> 	* cgraph.h: Likewise.
>> 	* cgraphunit.c (cgraph_node::create_wrapper): Usage of new argument introduced.
>> 	* ipa-devirt.c (polymorphic_type_binfo_p): Safe check for binfos created by Java.
>> 	* tree-ssa-alias.c (ao_ref_base_alias_set): Static function transformed to global.
>> 	* tree-ssa-alias.h: Likewise.
>
>> diff --git a/gcc/cgraph.c b/gcc/cgraph.c
>> index 8f04284..d40a2922 100644
>> --- a/gcc/cgraph.c
>> +++ b/gcc/cgraph.c
>> @@ -1637,13 +1637,15 @@ release_function_body (tree decl)
>>      are free'd in final.c via free_after_compilation().  */
>>
>>   void
>> -cgraph_node::release_body (void)
>> +cgraph_node::release_body (bool keep_arguments)
>>   {
>>     ipa_transforms_to_apply.release ();
>>     if (!used_as_abstract_origin && symtab->state != PARSING)
>>       {
>>         DECL_RESULT (decl) = NULL;
>> -      DECL_ARGUMENTS (decl) = NULL;
>> +
>> +      if (!keep_arguments)
>> +	DECL_ARGUMENTS (decl) = NULL;
>>       }
>>     /* If the node is abstract and needed, then do not clear DECL_INITIAL
>>        of its associated function function declaration because it's
>> diff --git a/gcc/cgraph.h b/gcc/cgraph.h
>> index a316e40..19ce3b8 100644
>> --- a/gcc/cgraph.h
>> +++ b/gcc/cgraph.h
>> @@ -915,7 +915,7 @@ public:
>>        Use this only for functions that are released before being translated to
>>        target code (i.e. RTL).  Functions that are compiled to RTL and beyond
>>        are free'd in final.c via free_after_compilation().  */
>> -  void release_body (void);
>> +  void release_body (bool keep_arguments = false);
>
> Please add documentation for KEEP_ARGUMENTS explaining that it is useful only if you want to
> rebuild body as thunk.
>>
>>     /* cgraph_node is no longer nested function; update cgraph accordingly.  */
>>     void unnest (void);
>> diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c
>> index 3e3b8d2..c4597e2 100644
>> --- a/gcc/cgraphunit.c
>> +++ b/gcc/cgraphunit.c
>> @@ -2300,7 +2300,7 @@ cgraph_node::create_wrapper (cgraph_node *target)
>>       tree decl_result = DECL_RESULT (decl);
>>
>>       /* Remove the function's body.  */
> I would say Remove the function's body but keep arguments to be reused for thunk.
>> -    release_body ();
>> +    release_body (true);
>>       reset ();
>>
>>       DECL_RESULT (decl) = decl_result;
>> diff --git a/gcc/ipa-devirt.c b/gcc/ipa-devirt.c
>> index af42c6d..f374933 100644
>> --- a/gcc/ipa-devirt.c
>> +++ b/gcc/ipa-devirt.c
>> @@ -225,7 +225,7 @@ static inline bool
>>   polymorphic_type_binfo_p (tree binfo)
>>   {
>>     /* See if BINFO's type has an virtual table associtated with it.  */
>> -  return BINFO_VTABLE (TYPE_BINFO (BINFO_TYPE (binfo)));
>> +  return BINFO_TYPE (binfo) && BINFO_VTABLE (TYPE_BINFO (BINFO_TYPE (binfo)));
>
> Aha, this change was for Java, right? Please add comment that Java produces
> BINFOs without BINFO_TYPE set.
>>   }
>>
>>   /* Return TRUE if all derived types of T are known and thus
>> diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
>> index 442112a..1bf88e2 100644
>> --- a/gcc/tree-ssa-alias.c
>> +++ b/gcc/tree-ssa-alias.c
>> @@ -559,7 +559,7 @@ ao_ref_base (ao_ref *ref)
>>
>>   /* Returns the base object alias set of the memory reference *REF.  */
>>
>> -static alias_set_type
>> +alias_set_type
>>   ao_ref_base_alias_set (ao_ref *ref)
>>   {
>>     tree base_ref;
>> diff --git a/gcc/tree-ssa-alias.h b/gcc/tree-ssa-alias.h
>> index 436381a..0d35283 100644
>> --- a/gcc/tree-ssa-alias.h
>> +++ b/gcc/tree-ssa-alias.h
>> @@ -98,6 +98,7 @@ extern void ao_ref_init (ao_ref *, tree);
>>   extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree);
>>   extern tree ao_ref_base (ao_ref *);
>>   extern alias_set_type ao_ref_alias_set (ao_ref *);
>> +extern alias_set_type ao_ref_base_alias_set (ao_ref *);
>
> I can not approve this change, but I suppose it is what Richard suggested?
>

There's updated version of the patch that deals with Honza's notes.
Yes, I explicitly asked Richard if we can mark the function as global.

I will commit the patch soon.

Thank you,
Martin

> Patch is OK except for the tree-ssa-alias bits.
> Honza
>>   extern bool ptr_deref_may_alias_global_p (tree);
>>   extern bool ptr_derefs_may_alias_p (tree, tree);
>>   extern bool ref_may_alias_global_p (tree);
>