Re: [PATCH] ASAN: handle addressable params (PR sanitize/81040).

["Martin Liška" <mliska@suse.cz>]

PING^1

On 06/20/2017 03:06 PM, Martin Liška wrote:
> On 06/20/2017 11:32 AM, Jakub Jelinek wrote:
>> On Tue, Jun 20, 2017 at 11:23:36AM +0200, Martin Liška wrote:
>>>> Then something needs to be done for debugging too.  If it is without VTA,
>>>> then probably just having DECL_VALUE_EXPR is good enough, otherwise
>>>> (VTA) you probably don't want that (or can reset it at that point), but
>>>> instead emit after the initialization stmt a debug stmt that the variable
>>>> value now lives in a different var.  Though ideally we want the debugger
>>>> to be able to also change the value of the var, that might be harder.
>>>> With DECL_VALUE_EXPR on the other side the debug info will be incorrect in
>>>> the prologue until it is assigned to the slot.
>>>
>>> Here I'm not sure about how to distinguish whether to build or not to build
>>> the debug statement. According to flag_var_tracking?
>>
>> More like if (target_for_debug_bind (arg))
>> And if that is false, just make sure DECL_VALUE_EXPR is set to var.
>>
>>> You mean something like:
>>> g = gimple_build_debug_bind (arg, var, g);
>>> ?
>>
>> Well, there is no stmt, so the last argument would be just NULL.
>>
>>>> I don't understand the distinction.  If you turn the original parm
>>>> for complex/vector DECL_GIMPLE_REG_P, you should need the exact same code
>>>> (but I think it would be better to use the default SSA_NAME of the PARM_DECL
>>>> if it is a gimple reg type, rather than use the PARM_DECL itself
>>>> and wait for update_ssa).
>>>
>>> Yes, the test-case /gcc/testsuite/g++.dg/asan/function-argument-3.C fails for me
>>> as one needs to have a temporary SSA name, otherwise:
>>>
>>> /home/marxin/Programming/gcc/gcc/testsuite/g++.dg/asan/function-argument-3.C:13:1: error: invalid rhs for gimple memory store
>>>  foo (v4si arg)
>>>  ^~~
>>> arg
>>>
>>> arg
>>>
>>> # .MEM_4 = VDEF <.MEM_1(D)>
>>> arg = arg;
>>> during GIMPLE pass: sanopt
>>>
>>> If I see correctly the function in my test-case does not have default def SSA name for the parameter.
>>> Thus I guess I need to create a SSA name?
>>
>> I'd expect if you have DECL_GIMPLE_REG_P set on the PARM_DECL and
>> use the default def, you shouldn't run into this.
>>
>> 	Jakub
>>
> 
> Good I fixed that in v2, that passes regression tests.
> Ale objections should be resolved in the version.
> 
> Ready for trunk?
> Martin
>