[GOOGLE] More strict checking for call args

[Xinliang David Li]

On Thu, Jun 6, 2013 at 7:11 AM, Martin Jambor <mjambor@suse.cz> wrote:
> Hi,
>
> On Tue, Jun 04, 2013 at 05:19:02PM -0700, Dehao Chen wrote:
>> attached is a testcase that would cause problem when source has changed:
>>
>> $ g++ test.cc -O2 -fprofile-generate -DOLD
>> $ ./a.out
>> $ g++ test.cc -O2 -fprofile-use
>> test.cc:34:1: internal compiler error: in operator[], at vec.h:815
>>  }
>>  ^
>> 0x512740 vec<tree_node*, va_heap, vl_embed>::operator[](unsigned int)
>> ../../gcc/vec.h:815
>> 0x512740 vec<tree_node*, va_heap, vl_ptr>::operator[](unsigned int)
>> ../../gcc/vec.h:1244
>> 0xf24464 vec<tree_node*, va_heap, vl_embed>::operator[](unsigned int)
>> ../../gcc/vec.h:815
>> 0xf24464 vec<tree_node*, va_heap, vl_ptr>::operator[](unsigned int)
>> ../../gcc/vec.h:1244
>> 0xf24464 ipa_get_indirect_edge_target_1
>> ../../gcc/ipa-cp.c:1535
>> 0x971b9a estimate_edge_devirt_benefit
>> ../../gcc/ipa-inline-analysis.c:2757
>
> Hm, this seems rather like an omission in ipa_get_indirect_edge_target_1.
> Since it is called also from inlining, we can have parameter count
> mismatches... and in fact in non-virtual paths of that function we do
> check that we don't.  Because all callers have to pass known_vals
> describing all formal parameters of the inline tree root, we should
> apply the fix below (I've only just started running a bootstrap and
> testsuite on x86_64, though).
>
> OTOH, while I understand that FDO can change inlining sufficiently so
> that this error occurs, IMHO this should not be caused by outdated
> profiles but there is somewhere a parameter mismatch in the source.

Martin, what do you mean by the above?

thanks,

David


>
> Dehao, can you please check that this patch helps?
>
> Richi, if it does and the patch passes bootstrap and tests, is it OK
> for trunk and 4.8 branch?
>
> Thanks and sorry for the trouble,
>
> Martin
>
>
> 2013-06-06  Martin Jambor  <mjambor@suse.cz>
>
>         * ipa-cp.c (ipa_get_indirect_edge_target_1): Check that param_index is
>         within bounds at the beginning of the function.
>
> Index: src/gcc/ipa-cp.c
> ===================================================================
> --- src.orig/gcc/ipa-cp.c
> +++ src/gcc/ipa-cp.c
> @@ -1481,7 +1481,8 @@ ipa_get_indirect_edge_target_1 (struct c
>    tree otr_type;
>    tree t;
>
> -  if (param_index == -1)
> +  if (param_index == -1
> +      || known_vals.length () <= (unsigned int) param_index)
>      return NULL_TREE;
>
>    if (!ie->indirect_info->polymorphic)
> @@ -1516,8 +1517,7 @@ ipa_get_indirect_edge_target_1 (struct c
>             t = NULL;
>         }
>        else
> -       t = (known_vals.length () > (unsigned int) param_index
> -            ? known_vals[param_index] : NULL);
> +       t = NULL;
>
>        if (t &&
>           TREE_CODE (t) == ADDR_EXPR