Re: [PATCH v3 0/7] fixes for rare issues

[Luc Van Oostenryck <luc.vanoostenryck@gmail.com>]

On Tue, Aug 1, 2017 at 12:34 AM, Luc Van Oostenryck
<luc.vanoostenryck@gmail.com> wrote:
> On Mon, Jul 31, 2017 at 11:54 PM, Luc Van Oostenryck
> <luc.vanoostenryck@gmail.com> wrote:
>> On Mon, Jul 31, 2017 at 11:01 PM, Christopher Li <sparse@chrisli.org> wrote:
>>> On Mon, Jul 31, 2017 at 4:36 PM, Luc Van Oostenryck
>>> <luc.vanoostenryck@gmail.com> wrote:
>>>> This series contains some fixes for crashes I found during
>>>> some fuzzy-testing, as well as for some infinite loops
>>>> that may happen during simplification.
>>>
>>> Thank you so much for the patch.
>>>
>>> I have to ask, is it for review (for now) or request to pull to
>>> sparse-next (drop the previous version in sparse-next)?
>>
>> It's for review & test as one patch is really changed and two
>> are new and while small induce big changes.
>
> One of the thing I haven't tested is the performance.
> Several things here can make things slower:
> - REPEAT_CFG_CLEANUP is now set after every call to rewrite_branch()
>   (and will then trigger at some point a call to kill_unreachable_bbs())
> - kill_unreachable_bbs() set REPEAT_CSE is a BB have been deleted
>   (which may trigger another CSE cycle possibly not present before)
> - the bb_depends_on() change add some code with looping through
>   the BB's instructions, nothing really heavy but still some more code
>   to run
> All these are needed though.

And indeed I see that some tests that took me 38s now take 48s.
I'll look tomorrow for the real cause and see what can be done there.

-- Luc