Re: [PATCH][RFC] Sanity checking for -freorder-blocks-and-partition failures

[Teresa Johnson <tejohnson at google dot com>]

On Wed, Oct 31, 2012 at 12:58 PM, Christophe Lyon
<christophe.lyon@st.com> wrote:
> On 30.10.2012 17:59, Teresa Johnson wrote:
>>
>> On Tue, Oct 30, 2012 at 9:26 AM, Steven Bosscher <stevenb.gcc@gmail.com>
>> wrote:
>>>
>>> Hello,
>>>
>>> Hot/cold partitioning is apparently a hot topic all of a sudden, which
>>> is a good thing of course, because it's in need of some TLC.
>>>
>>> The attached patch adds another check the RTL cfg checking
>>> (verify_flow_info) for the partitioning: A hot block can never be
>>> dominated by a cold block (because the dominated block must also be
>>> cold). This trips in PR55121.
>>>
>>> I haven't tested this with any profiling tests, but it's bound to
>>> break things. From my POV, whatever gets broken by this patch was
>>> already broken to begin with :-)   If you're in CC, it's because I
>>> hope you can help test this patch.
>>
>> I will try testing your patch on top of mine with our fdo benchmarks.
>> 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
>>
>> Teresa
>>
> I have tried Steven's patch an indeed it reported numerous errors while
> compiling spec2k.
>
> I tried Teresa's patch too, but it changed nothing in my tests. The patches
> already posted by Matt are still necessary and Teresa's patch does not
> improve my tests.

With checking enabled I am seeing additional failures that my fixes
are not addressing. Looking into those now.
Can someone point me to Matt's patches? Is that this one:
http://gcc.gnu.org/ml/gcc-patches/2012-09/msg00274.html
or are there others?

Thanks,
Teresa

>
> I am out of office at the moment, so it's a little bit inconvenient to
> investigate deeper the reasons for all the errors reported by Steven's
> patch. Anyway it looks like it's really needed :)
> I also noticed that some compilations failed with an ICE in calc_dfs_tree at
> dominance.c:395.
>
>
> Christophe.
>



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Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413