Re: Dump before flag

[Richard Guenther <richard.guenther@gmail.com>]

On Thu, Jun 9, 2011 at 5:47 PM, Xinliang David Li <davidxl@google.com> wrote:
> See attached.

Hmm.  I don't like how you still wire dumping in the TODO routines.
Doesn't it work to just dump the body from pass_fini_dump_file ()?
Or if that doesn't sound clean from (a subset of) places where it
is called? (we might want to exclude the ipa read/write/summary
stages)

Richard.

> Thanks,
>
> David
>
> On Thu, Jun 9, 2011 at 2:02 AM, Richard Guenther
> <richard.guenther@gmail.com> wrote:
>> On Thu, Jun 9, 2011 at 12:31 AM, Xinliang David Li <davidxl@google.com> wrote:
>>> this is the patch that just removes the TODO_dump flag and forces it
>>> to dump. The original code cfun->last_verified = flags &
>>> TODO_verify_all looks weird -- depending on TODO_dump is set or not,
>>> the behavior of the update is different (when no other todo flags is
>>> set).
>>>
>>> Ok for trunk?
>>
>> -ENOPATCH.
>>
>> Richard.
>>
>>> David
>>>
>>> On Wed, Jun 8, 2011 at 9:52 AM, Xinliang David Li <davidxl@google.com> wrote:
>>>> On Wed, Jun 8, 2011 at 2:06 AM, Richard Guenther
>>>> <richard.guenther@gmail.com> wrote:
>>>>> On Wed, Jun 8, 2011 at 1:08 AM, Xinliang David Li <davidxl@google.com> wrote:
>>>>>> The following is the patch that does the job. Most of the changes are
>>>>>> just  removing TODO_dump_func. The major change is in passes.c and
>>>>>> tree-pass.h.
>>>>>>
>>>>>> -fdump-xxx-yyy-start       <-- dump before TODO_start
>>>>>> -fdump-xxx-yyy-before    <-- dump before main pass after TODO_pass
>>>>>> -fdump-xxx-yyy-after       <-- dump after main pass before TODO_finish
>>>>>> -fdump-xxx-yyy-finish      <-- dump after TODO_finish
>>>>>
>>>>> Can we bikeshed a bit more about these names?
>>>>
>>>> These names may be less confusing:
>>>>
>>>> before_preparation
>>>> before
>>>> after
>>>> after_cleanup
>>>>
>>>> David
>>>>
>>>>> "start" and "before"
>>>>> have no semantical difference to me ... as the dump before TODO_start
>>>>> of a pass and the dump after TODO_finish of the previous pass are
>>>>> identical (hopefully ;)), maybe merge those into a -between flag?
>>>>> If you'd specify it for a single pass then you'd get both -start and -finish
>>>>> (using your naming scheme).  Splitting that dump(s) to different files
>>>>> then might make sense (not sure about the name to use).
>>>>>
>>>>> Note that I find it extremely useful to have dumping done in
>>>>> chronological order - splitting some of it to different files destroys
>>>>> this, especially a dump after TODO_start or before TODO_finish
>>>>> should appear in the same file (or we could also start splitting
>>>>> individual TODO_ output into sub-dump-files).  I guess what would
>>>>> be nice instread would be a fancy dump-file viewer that could
>>>>> show diffs, hide things like SCEV output, etc.
>>>>>
>>>>> I suppose a patch that removes the dump TODO and unconditionally
>>>>> dumps at the current point would be a good preparation for this
>>>>> enhancing patch.
>>>>>
>>>>> Richard.
>>>>>
>>>>>> The default is 'finish'.
>>>>>>
>>>>>> Does it look ok?
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>> David
>>>>>>
>>>>>> On Tue, Jun 7, 2011 at 2:36 AM, Richard Guenther
>>>>>> <richard.guenther@gmail.com> wrote:
>>>>>>> On Mon, Jun 6, 2011 at 6:20 PM, Xinliang David Li <davidxl@google.com> wrote:
>>>>>>>>>
>>>>>>>>> Your patch doesn't really improve this but adds to the confusion.
>>>>>>>>>
>>>>>>>>> +  /* Override dump TODOs.  */
>>>>>>>>> +  if (dump_file && (pass->todo_flags_finish & TODO_dump_func)
>>>>>>>>> +      && (dump_flags & TDF_BEFORE))
>>>>>>>>> +    {
>>>>>>>>> +      pass->todo_flags_finish &= ~TODO_dump_func;
>>>>>>>>> +      pass->todo_flags_start |= TODO_dump_func;
>>>>>>>>> +    }
>>>>>>>>>
>>>>>>>>> and certainly writing to pass is not ok.  And the TDF_BEFORE flag
>>>>>>>>> looks misplaced as it controls TODOs, not dumping behavior.
>>>>>>>>> Yes, it's a mess right now but the above looks like a hack ontop
>>>>>>>>> of that mess (maybe because of it, but well ...).
>>>>>>>>>
>>>>>>>>
>>>>>>>> How about removing dumping TODO completely -- this can be done easily
>>>>>>>> -- I don't understand why pass wants extra control on the dumping if
>>>>>>>> user already asked for dumping -- it is annoying to see empty IR dump
>>>>>>>> for a pass when I want to see it.
>>>>>>>>
>>>>>>>>> At least I would have expected to also get the dump after the
>>>>>>>>> pass, not only the one before it with this dump flag.
>>>>>>>>>
>>>>>>>>> Now, why can't you look at the previous pass output for the
>>>>>>>>> before-dump (as I do usually)?
>>>>>>>>
>>>>>>>> For one thing, you need to either remember what is the previous pass,
>>>>>>>> or dump all passes which for large files can take very long time. Even
>>>>>>>> with all the dumps, you will need to eyeballing to find the previous
>>>>>>>> pass which may or may not have the IR dumped.
>>>>>>>>
>>>>>>>> How about removing dump TODO?
>>>>>>>
>>>>>>> Yeah, I think this would go in the right direction.  Currently some passes
>>>>>>> do not dump function bodies because they presumably do no IL
>>>>>>> modification.  But this is certainly the minority (and some passes do not
>>>>>>> dump bodies even though they are modifying the IL ...).
>>>>>>>
>>>>>>> So I'd say we should by default dump function bodies.
>>>>>>>
>>>>>>> Note that there are three useful dumping positions (maybe four),
>>>>>>> before todo-start, after todo-start, before todo-finish and after todo-finish.
>>>>>>> By default we'd want after todo-finish.  When we no longer dump via
>>>>>>> a TODO then we could indeed use dump-flags to control this
>>>>>>> (maybe -original for the body before todo-start).
>>>>>>>
>>>>>>> What to others think?
>>>>>>>
>>>>>>> Richard.
>>>>>>>
>>>>>>>> Thanks,
>>>>>>>>
>>>>>>>> David
>>>>>>>>
>>>>>>>>
>>>>>>>>>
>>>>>>>>> Richard.
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>