2011/5/11 Richard Guenther <[email protected]>:
> On Wed, May 11, 2011 at 11:00 AM, Kai Tietz <[email protected]> wrote:
>> Hi,
>>
>> By investigating the conditional expression handling I found some
>> causes, why TRUTH operations AND, ANDIF, OR, XOR, and ORIF are
>> appearing withing conditional folding during gimplification.
>> The reason for this can be that the truth expression is simply used as
>> result of an assignment or return statement, which then leads to the
>> issue that expression has lhs type. By this reason it is still
>> necessary to have in TRUTH operations type-cast after boolifying it
>> for later operation, if type isn't of kind boolean. Therefore it is
>> necessary for conditional to check if their arms might be TRUTH
>> results and therefore doing boolification of the arms, too.
>
> You are not making much sense - gimple_boolify already boolifies
> both arms. It assumes that if the expr is bool already the arms are
> as well - I'm not sure that always holds, so defering that check as
> your patch did probably makes sense.
It makes absolutely sense. Simply try the following example:
int
foo (int a, int b, int c)
{
int e = (a && b);
return e ? (c && !a) : (c && a && b);
}
You will see that by this you have TRUTH AND operations with none
boolean type, due the fact that for a conditional only the cond part
was converted. This patch checks that inner arms getting boolified, if
result of condition on both arms is a TRUTH result.
Regards,
Kai
