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Re: TODO_rebuild_alias and -O0
Richard Guenther <richard.guenther@gmail.com> skribis:
> On Mon, Oct 8, 2012 at 11:58 AM, Ludovic CourtÃs <ludo@gnu.org> wrote:
>> Richard Guenther <richard.guenther@gmail.com> skribis:
>>
>>> At -O0 no virtual operands are produced. TODO_rebuild_alias only computes
>>> points-to sets which are in itself not useful.
>>>
>>> What do you want to achieve with TODO_rebuild_alias?
>>
>> I basically want to use âptr_derefs_may_alias_pâ in this particular pass.
>
> That should work.
It actually does, except that âptr_derefs_may_alias_pâ returns true for
two SSA names in cases like this:
double *p, *q;
p = malloc (123);
q = malloc (234);
(Where âmallocâ has the âmallocâ attribute.)
For some reason, thereâs no such false positive when using TODO_rebuild_alias.
Ludoâ.