Dump before flag

[Xinliang David Li]

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?

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.
>>>>>>
>>>>>
>>>>
>>>
>>
>