[PINGv2][PATCH] ASan phase place change

[Yury Gribov]

On 03/11/2015 10:43 AM, Marat Zakirov wrote:
>
> On 03/03/2015 10:36 AM, Marat Zakirov wrote:
>>
>> On 02/24/2015 03:49 PM, Marat Zakirov wrote:
>>>
>>> On 02/20/2015 03:07 PM, Jakub Jelinek wrote:
>>>> On Fri, Feb 20, 2015 at 02:59:51PM +0300, Marat Zakirov wrote:
>>>>> Here is simple patch that moves asan phase just behind sanopt for all
>>>>> O0/O1/O2/O3 modes which gives +7% on x86 SPEC2006 (ref dataset).
>>>>> Regression testing and sanitized GCC bootstrapping were
>>>>> successfully done.
>>>> This isn't a regression, so I think it isn't appropriate for stage 4.
>>>>
>>>> I bet the difference is mainly vectorization.  I believe the right
>>>> change is to teach the vectorizer about the ASAN_CHECK internal call
>>>> instead.
>>>>
>>>>     Jakub
>>>>
>>> Jakub,
>>>
>>> I reproduced +28% for 433.milk with "-fno-tree-vectorize" on ref
>>> data. Are there some other GCC vectorization options? And why do you
>>> think that performance difference caused only by vectorization? As an
>>> example In llvm loop hoisting suffers from early asan phase
>>> http://lists.cs.uiuc.edu/pipermail/llvmdev/2011-December/046332.html.

I think it would help if we could analyze where performance improvements 
are coming from. You can check Max's presentation for inspiration 
(http://www.youtube.com/watch?v=qTDBHJsWDHw).

-Y