RFR(s): 8222637: Obsolete NeedsDeoptSuspend (was RFR(s): 8222640: Remove deopt suspend)

[Robbin Ehn]

Hi,

The same patch as in 8222640 but with obsoleting of the flag also.

Issue:
https://bugs.openjdk.java.net/browse/JDK-8222637
CSR:
https://bugs.openjdk.java.net/browse/JDK-8222639

The incremental change is thus:
http://cr.openjdk.java.net/~rehn/8222637/webrev/src/hotspot/share/runtime/globals.hpp.sdiff.html
http://cr.openjdk.java.net/~rehn/8222637/webrev/src/hotspot/share/runtime/arguments.cpp.sdiff.html

Full:
http://cr.openjdk.java.net/~rehn/8222637/webrev/

Dead and Coleen had previously review 8222640, so if they can acknowledge this 
inc change.

Thanks, Robbin

On 4/24/19 1:49 AM, Robbin Ehn wrote:
> Thanks Coleen!
> 
> /Robbin
> 
> On 2019-04-24 00:47, coleen.phillimore at oracle.com wrote:
>> +1  This looks good!
>> Coleen
>>
>> On 4/23/19 5:32 PM, Robbin Ehn wrote:
>>> Thanks Dean!
>>>
>>> /Robbin
>>>
>>> On 2019-04-23 23:17, dean.long at oracle.com wrote:
>>>> Yes, looks good!
>>>>
>>>> dl
>>>>
>>>> On 4/23/19 12:38 PM, Robbin Ehn wrote:
>>>>> Hi Dean,
>>>>>
>>>>> Is this what you had in mind:
>>>>> diff -r 295029840379 src/hotspot/share/runtime/frame.cpp
>>>>> --- a/src/hotspot/share/runtime/frame.cpp       Tue Apr 23 09:58:55 2019 +0200
>>>>> +++ b/src/hotspot/share/runtime/frame.cpp       Tue Apr 23 21:32:00 2019 +0200
>>>>> @@ -272,4 +272,6 @@
>>>>>
>>>>>  void frame::deoptimize(JavaThread* thread) {
>>>>> +  assert(thread->frame_anchor()->has_last_Java_frame() &&
>>>>> +         thread->frame_anchor()->walkable(), "must be");
>>>>>    // Schedule deoptimization of an nmethod activation with this frame.
>>>>>    assert(_cb != NULL && _cb->is_compiled(), "must be");
>>>>>
>>>>> Passes t1-5.
>>>>>
>>>>> v2:
>>>>> http://cr.openjdk.java.net/~rehn/8222640/2/webrev/
>>>>> Inc:
>>>>> http://cr.openjdk.java.net/~rehn/8222640/2/inc/webrev/
>>>>>
>>>>> Thanks, Robbin
>>>>>
>>>>> On 2019-04-18 06:22, dean.long at oracle.com wrote:
>>>>>> In frame::deoptimize(), can we assert that we have an anchor frame and 
>>>>>> that it is walkable?
>>>>>>
>>>>>> dl
>>>>>>
>>>>>> On 4/17/19 3:09 AM, Robbin Ehn wrote:
>>>>>>> Adding compiler.
>>>>>>>
>>>>>>> /Robbin
>>>>>>>
>>>>>>> On 4/17/19 10:35 AM, Robbin Ehn wrote:
>>>>>>>> Hi all, please consider this change.
>>>>>>>>
>>>>>>>> The code for deopt suspend is no longer needed since today the register 
>>>>>>>> window
>>>>>>>> is always flushed when this code executes. Exactly when this code was 
>>>>>>>> needed is not clear, entered via duke changeset 1. I did not dig since 
>>>>>>>> we no longer have such use case.
>>>>>>>>
>>>>>>>> Webrev:
>>>>>>>> http://cr.openjdk.java.net/~rehn/8222640/webrev/
>>>>>>>> Issue:
>>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8222640
>>>>>>>>
>>>>>>>> Passes t1-5.
>>>>>>>>
>>>>>>>> Thanks, Robbin
>>>>>>
>>>>
>>