Re: [PATCH, Pointer Bounds Checker 3/x] Target hooks for Pointer Bounds Checker

[Jeff Law <law@redhat.com>]

On 08/15/14 09:08, Ilya Enkovich wrote:
> On 17 Jul 03:36, Jeff Law wrote:
>> On 04/16/14 05:52, Ilya Enkovich wrote:
>>> diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
>>> index b8ca17e..d868129 100644
>>> --- a/gcc/doc/tm.texi
>>> +++ b/gcc/doc/tm.texi
>>> @@ -4333,6 +4333,13 @@ This hook returns the va_list type of the calling convention specified by
>>>   The default version of this hook returns @code{va_list_type_node}.
>>>   @end deftypefn
>>>
>>> +@deftypefn {Target Hook} tree TARGET_FN_ABI_VA_LIST_BOUNDS_SIZE (tree @var{fndecl})
>>> +This hook returns size for @code{va_list} object in function specified
>>> +by @var{fndecl}.  This hook is used by Pointer Bounds Checker to build bounds
>>> +for @code{va_list} object.  Return @code{integer_zero_node} if no bounds
>>> +should be used (e.g. @code{va_list} is a scalar pointer to the stack).
>>> +@end deftypefn
>> What if va_list is an aggregate, but lives in registers?  I'm not
>> familiar with the different va_list implementations on all the
>> targets, but GCC has supported aggregates in registers for various
>> ABIs through the years.
>>
>>> +@deftypefn {Built-in Function} size_t __chkp_sizeof (const void *@var{ptr})
>>> +Function code - @code{BUILT_IN_CHKP_SIZEOF}.  This built-in function
>>> +returns size of object referenced by @var{ptr}. @var{ptr} is always
>>> +@code{ADDR_EXPR} of @code{VAR_DECL}.  This built-in is used by
>>> +Pointer Boudns Checker when bounds of object cannot be computed statically
>>> +(e.g. object has incomplete type).
>> s/Boudns/Bounds/
>>
>> OK for the trunk with those two doc fixes.  As with the other
>> patches, wait for the remainder to be approved before committing.
>>
>> jeff
>>
>
> Thanks for comments!
>
> TARGET_FN_ABI_VA_LIST_BOUNDS_SIZE was supposed to be used when va_list is a pointer to a structure holding args (as it is for x86_64 where we have a structure holding all incoming registers).  I decided to remove TARGET_FN_ABI_VA_LIST_BOUNDS_SIZE hook because all loads from va_list are generated by compiler and should be safely within its bounds.
>
> Here is an updated patch.
>
> Thanks,
> Ilya
> --
> 2014-08-15  Ilya Enkovich  <ilya.enkovich@intel.com>
>
> 	* target.def (builtin_chkp_function): New.
> 	(chkp_bound_type): New.
> 	(chkp_bound_mode): New.
> 	(chkp_make_bounds_constant): New.
> 	(chkp_initialize_bounds): New.
> 	(load_bounds_for_arg): New.
> 	(store_bounds_for_arg): New.
> 	(load_returned_bounds): New.
> 	(store_returned_bounds): New.
> 	(chkp_function_value_bounds): New.
> 	(setup_incoming_vararg_bounds): New.
> 	* targhooks.h (default_load_bounds_for_arg): New.
> 	(default_store_bounds_for_arg): New.
> 	(default_load_returned_bounds): New.
> 	(default_store_returned_bounds): New.
> 	(default_chkp_bound_type): New.
> 	(default_chkp_bound_mode): New.
> 	(default_builtin_chkp_function): New.
> 	(default_chkp_function_value_bounds): New.
> 	(default_chkp_make_bounds_constant): New.
> 	(default_chkp_initialize_bounds): New.
> 	(default_setup_incoming_vararg_bounds): New.
> 	* targhooks.c (default_load_bounds_for_arg): New.
> 	(default_store_bounds_for_arg): New.
> 	(default_load_returned_bounds): New.
> 	(default_store_returned_bounds): New.
> 	(default_chkp_bound_type): New.
> 	(default_chkp_bound_mode); New.
> 	(default_builtin_chkp_function): New.
> 	(default_chkp_function_value_bounds): New.
> 	(default_chkp_make_bounds_constant): New.
> 	(default_chkp_initialize_bounds): New.
> 	(default_setup_incoming_vararg_bounds): New.
> 	* doc/tm.texi.in (TARGET_LOAD_BOUNDS_FOR_ARG): New.
> 	(TARGET_STORE_BOUNDS_FOR_ARG): New.
> 	(TARGET_LOAD_RETURNED_BOUNDS): New.
> 	(TARGET_STORE_RETURNED_BOUNDS): New.
> 	(TARGET_CHKP_FUNCTION_VALUE_BOUNDS): New.
> 	(TARGET_SETUP_INCOMING_VARARG_BOUNDS): New.
> 	(TARGET_BUILTIN_CHKP_FUNCTION): New.
> 	(TARGET_CHKP_BOUND_TYPE): New.
> 	(TARGET_CHKP_BOUND_MODE): New.
> 	(TARGET_CHKP_MAKE_BOUNDS_CONSTANT): New.
> 	(TARGET_CHKP_INITIALIZE_BOUNDS): New.
> 	* doc/tm.texi: Regenerated.
>
Just to be explicit, this is OK when the rest of the pointer bounds 
stuff goes in.

jeff