RFR 8239782: CC_INTERP is only used by Zero interpreter

[David Holmes]

I thoroughly applaud the introduction of interpreter/zero directory! 
Thank you. :)

Updates look good to me.

Thanks,
David

On 24/06/2020 6:35 am, coleen.phillimore at oracle.com wrote:
> 
> Including build-dev.
> 
> On 6/23/20 12:17 AM, David Holmes wrote:
>> Hi Coleen,
>>
>> Cleanup is looking good but a few comments:
>>
>> - if the bytecodeInterpreter is also zero-only can we rename its files 
>> too? (I really find it hard to figure out which files are really 
>> needed/used for a given build.)
> 
> You're right that bytecodeInterpreter* files in the interpreter 
> directory always confuses everybody.  So I moved them to 
> src/hotspot/share/interpreter/zero.  I also fixed the build to not build 
> that directory unless you're building zero.
> 
> I removed a few more unnecessary #includes.
>>
>> - you are excluding shared templateInterpreter*.* from the zero build so
>> "#ifndef ZERO" is always true in those files.
> 
> The templateInterpreter header files still need #ifndef ZERO because 
> they can be transitively included in interpreter.hpp.  I removed #ifndef 
> ZERO from the .cpp files only.
> 
>>
>> - are the platform specific templateInterpreter* files already 
>> excluded from a zero build? Otherwise they should be added to the 
>> exclude list.
> 
> They are already excluded because zero doesn't build those platform files.
> 
>>
>> - how were you able to completely delete:
>>   - src/hotspot/share/interpreter/cppInterpreter.cpp
>>   - src/hotspot/share/interpreter/cppInterpreterGenerator.cpp
>> ?
> 
> I inlined them into the cpu/zero/*_zero versions.
> 
> So the additional changes to move the bytecodeInterpreter* and zero 
> files to a zero directory are here.  I didn't want to move them to the 
> cpu/zero directory because they are not analogs to the other cpu files.
> 
> incremental:http://cr.openjdk.java.net/~coleenp/2020/8239782.02.incr/webrev/index.html
> full: http://cr.openjdk.java.net/~coleenp/2020/8239782.02/webrev/
> 
> Tested with tier1 on Oracle platforms and zero product and fastdebug 
> build.  CC'ing Adrian who works on Zero, can you comment on this patch?
> 
> Thanks,
> Coleen
>>
>> Thanks,
>> David
>> ----
>>
>>
>> On 23/06/2020 1:36 am, coleen.phillimore at oracle.com wrote:
>>> Summary: Change CC_INTERP conditional to ZERO and remove in places 
>>> where unnecessary. Fix build to exclude compilers and rename 
>>> CppInterpreter to ZeroInterpreter. The "C++ Interpreter" has been 
>>> removed from the code a while ago.
>>>
>>> The motivation is to remove CC_INTERP conditionals from common code 
>>> for the most part.  The C++ interpreter used to work with C1 and C2.  
>>> Some of the hooks are still present (can be cleaned out or 
>>> implemented correctly later) but I removed some other unconditionally 
>>> false code in order to remove interactions with common code.  Also it 
>>> appeared that Zero was creating method counters when it was never 
>>> using them.  I removed this too, hoping it would make zero faster, 
>>> but nope, it's still slow.
>>>
>>> I also renamed cppInterpreter and CppInterpreter to zeroInterpreter 
>>> and ZeroInterpreter, respectively, and moved some code to cpu/zero. 
>>> Thus ends pass 10? of cleaning up this code.
>>>
>>> Tested with tier1 on Oracle platforms and built these: 
>>> linux-arm32,linux-ppc64le-debug,linux-s390x-debug,linux-x64-zero,linux-x64-zero-debug. 
>>> If you work on Zero, can you give this a test run with your favorite 
>>> platform and review?
>>>
>>> open webrev at 
>>> http://cr.openjdk.java.net/~coleenp/2020/8239782.01/webrev
>>> bug link https://bugs.openjdk.java.net/browse/JDK-8239782
>>>
>>> Thanks,
>>> Coleen
>>>
>