PATCH: PR middle-end/39297: [4.4 Regression] gcc.dg/tree-ssa/loop-31.c

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Tue, Feb 24, 2009 at 7:01 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Tue, Feb 24, 2009 at 3:02 AM, Richard Guenther <rguenther@suse.de> wrote:
>> On Tue, 24 Feb 2009, Richard Guenther wrote:
>>
>>> On Mon, 23 Feb 2009, Zdenek Dvorak wrote:
>>>
>>> > Hi,
>>> >
>>> > > > > Can you have a look at the testcase in PR39233?
>>> > > >
>>> > > > here is a patch; I do not have time to test it just now. ?It could be
>>> > > > simplified by casting the values to unsigned type in
>>> > > > add_iv_value_candidates unconditionally (most of the patch makes
>>> > > > us push the value of the no_overflow flag there, so that we do not
>>> > > > add these casts when not necessary).
>>> > >
>>> > > I am going to give the patch testing, most of it looks like useful
>>> > > cleanup. ?Note that using unsigned_type_for is probably not a good
>>> > > idea, so I'll change it to use get_nonstandard_integer_type instead.
>>> >
>>> > actually, looking at the issue again, there already is a code dealing
>>> > with this problem in add_candidate_1; unfortunately, there is a test
>>> > excluding pointers from being casted to a safe type, which causes
>>> > PR39233. ?So, it should suffice to remove that test,
>>>
>>> Indeed, that works. ?The previous patch bootstrapped and tested ok,
>>> I'm going to test the simpler one now.
>>
>> Done as follows. ?Bootstrapped and tested on x86_64-unknown-linux-gnu,
>> applied to trunk.
>>
>> Thanks,
>> Richard.
>>
>> 2009-02-24 ?Richard Guenther ?<rguenther@suse.de>
>> ? ? ? ?Zdenek Dvorak ?<ook@ucw.cz>
>>
>> ? ? ? ?PR tree-optimization/39233
>> ? ? ? ?* tree-ssa-loop-ivopts.c (add_candidate_1): Do not except pointers
>> ? ? ? ?from converting them to a generic type.
>>
>> ? ? ? ?* gcc.c-torture/execute/pr39233.c: New testcase.
>>
>
> This patch may be the cause for
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39297
>
>

There is a problem in PR 39233 only when base is a constant.
I am testing this patch. OK for trunk if there are regressions on
Linux/ia32, Linux/ia64 and Linux/x86-64.

Thanks.


-- 
H.J.
---
2008-02-25  H.J. Lu  <hongjiu.lu@intel.com>

	PR middle-end/39297
	* tree-ssa-loop-ivopts.c (add_candidate_1): Except pointers
	from converting them to a generic type unless the base is a
	constant.

Attachment: gcc-pr39297-1.patch
Description: Text document