RFR 8239782: CC_INTERP is only used by Zero interpreter

[David Holmes]

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 are excluding shared templateInterpreter*.* from the zero build so
"#ifndef ZERO" is always true in those files.

- are the platform specific templateInterpreter* files already excluded 
from a zero build? Otherwise they should be added to the exclude list.

- how were you able to completely delete:
   - src/hotspot/share/interpreter/cppInterpreter.cpp
   - src/hotspot/share/interpreter/cppInterpreterGenerator.cpp
?

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
>