[PATCH] Do not store/stream binfos in jump functions

[Martin Jambor]

Hi,

On Fri, Sep 16, 2011 at 04:29:44PM +0200, Jan Hubicka wrote:
> > 
> > 	* ipa-prop.h (jump_func_type): Updated comments.
> > 	(ipa_known_type_data): New type.
> > 	(ipa_jump_func): Use it to describe known type jump functions.
> > 	* ipa-prop.c (ipa_print_node_jump_functions_for_edge): Updated to
> > 	reflect the new known type jump function contents.
> > 	(compute_known_type_jump_func): Likewise.
> > 	(combine_known_type_and_ancestor_jfs): Likewise.
> > 	(try_make_edge_direct_virtual_call): Likewise.
> > 	(ipa_write_jump_function): Likewise.
> > 	(ipa_read_jump_function): Likewise.
> > 	* ipa-cp.c (ipa_value_from_known_type_jfunc): New function.
> > 	(ipa_value_from_jfunc): Use ipa_value_from_known_type_jfunc.
> > 	(propagate_accross_jump_function): Likewise.
> 
> OK. If we saved just one pointer to the actual type (i.e. not
> BINFO), would it be any sanier?

I'm not sure if I understand the question.  In any event, the
base_type is certainly not enough, the offset is 100% necessary - it
identifies the vptr in the structure which we have to know because the
indices (tokens) in OBJ_TYPE_REFs are relative to what that vptr, not
the first vptr, points to.

I have attempted to remove the component_type (which means to remove
the expected_type in get_binfo_at_offset) but my first simple attempts
could lead to missed optimizations in cases we can currently handle.
I still have one idea that might work, I will try.

Meanwhile, I will re-test the patch on a current svn checkout and
commit it if all goes fine.

Thanks,

Martin