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Re: [PATCH][RFC] Sanity checking for -freorder-blocks-and-partition failures
There are not many -- see gcc/testsuite/gcc.dg/tree-prof directory.
Under that, 5 cases explicitly set the option.
David
On Tue, Oct 30, 2012 at 2:31 PM, Teresa Johnson <tejohnson@google.com> wrote:
> On Tue, Oct 30, 2012 at 12:33 PM, Xinliang David Li <davidxl@google.com> wrote:
>> On Tue, Oct 30, 2012 at 12:25 PM, Steven Bosscher <stevenb.gcc@gmail.com> wrote:
>>> On Tue, Oct 30, 2012 at 5:59 PM, Teresa Johnson wrote:
>>>> I will try testing your patch on top of mine with our fdo benchmarks.
>>>
>>> Thanks. But you should expect a lot of errors, hopefully you can make
>>> something out of it for Bugzilla.
>
> I didn't hit it, but I see it looks like I need to enable checking to
> get to this verification routine. Just rebuilt with checking enabled
> and redoing my builds.
>
>>>
>>>> For the others on the cc list, you may need to include my patch as
>>>> well for testing. Without it, -freorder-blocks-and-partition was DOA
>>>> for me. For my patch, see
>>>> http://gcc.gnu.org/ml/gcc-patches/2012-10/msg02692.html
>>>
>>> Ah, the fate of a pass that isn't enabled by default.
>>
>> I see only 5 test cases under tree-prof for function splitting. More
>> test cases are needed.
>
> In an attempt to provoke the failures I was seeing on a smaller test
> case, I tried enabling -freorder-blocks-and-partition by default in my
> common.opt file and running through the regression test suite (without
> my fixes). But I didn't hit any of the failures. Perhaps there aren't
> many profile-use tests.
>
> Teresa
>
>
>>
>> David
>>
>>
>>> From what I can
>>> tell, looking at this code the past few hours, it's hopelessly broken
>>> at the moment:
>>>
>>> * It doesn't work with cfglayout mode, even though it is in between
>>> pass_into_cfg_layout_mode and pass_outof_cfg_layout_mode. Coming out
>>> of cfglayout mode
>>>
>>> * Coming out of cfglayout mode, fixup_reorder_chain adds
>>> REG_CROSSING_JUMP -- but so does force_nonfallthru_and_redirect called
>>> just before it. So we end up with >1 such note, or with notes on jumps
>>> that shouldn't have them.
>>>
>>> * The scheduler doesn't respect the partitioning at all. remove_notes
>>> happily removes the section split note.
>>>
>>> * etc.
>>>
>>>
>>> This pass may need some major work to be in good order again.
>>>
>>> Ciao!
>>> Steven
>
>
>
> --
> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413