[LLVMdev] How to make Polly ignore some non-affine memory accesses

[Tobias Grosser]

On 11/20/2011 03:01 AM, Marcello Maggioni wrote:
> 2011/11/19 Tobias Grosser<tobias at grosser.es>:
>> On 11/18/2011 01:34 PM, Marcello Maggioni wrote:
>>>
>>> Ok , this is what I believe is the final patch that adds the
>>> non-affine accept functionality to Polly, this should have no issues.
>>>
>>> I added three tests, two in ScopInfo (two simple tests, one expected
>>> fail and one success based on the same source) and one in CodeGen that
>>> verifies that the code is generated.
>>>
>>> The patch is attached.
>>
>> The patch includes only one test case. I also have some tiny last comments
>> inline. Otherwise the patch looks good.
>>
>>> +++ test/ScopInfo/simple_nonaffine_loop_exfail.ll     (revision 0)
>>> @@ -0,0 +1,42 @@
>>> +; RUN: opt %loadPolly %defaultOpts -polly-scops -analyze %s |
>>> FileCheck %s
>>> +; XFAIL: *
>>
>> Why is this one still XFAIL?
>
> I wanted to add a test case that in case of a "missing the flag" at
> command line confirmed the functionality was actually disabled (and
> this is the reason of the XFAIL test).he
XFAIL it not the way to test this. You can just add another command line
to the passing test, remove the flag to enable non-affine access 
functions and replace '| FileCheck' with '| not FileCheck'.

> Originally you said I had to add a minimst al test case to the patch,
> should I add some more tests now withore complex scops?

I do not see that a more complex scope would test more of the feature. 
You could add a test case where the access subscript is not a valid
SCEV, but COULD_NOT_COMPUTE.

Cheers
Tobi