RFR: 8171853: Remove Shark compiler

[coleen.phillimore at oracle.com]

On 10/15/17 2:06 AM, John Paul Adrian Glaubitz wrote:
> Hi Roman!
>
> Please let me look at SPARC next week first before merging this.
>
> And thanks for notifying me that Zero is broken again *sigh*.
>
> People, please test your changes. Yes, I know you all just care about Hotspot. But please understand that there are many people out there who rely on Zero, i.e. they are using it. Breaking code that people actively use is not nice and should not happen in a project like OpenJDK.
>
> Building Zero takes maybe 5 minutes on a fast x86 machine, so I would like to ask everyone to please test their changes against Zero as well. These tests will keep the headaches for people relying on Zero low and also avoids that distributions have to ship many patches on top of OpenJDK upstream.

I used to be able to compile and link Zero and have fixed it but as an 
occasional task, it's something that stops working.

At one point, I thought I'd filed an internal bug so that zero is built 
in JPRT.

So I can compile zero again, but can't link on OL7 (Oracle's RedHat 
version of linux).

Error: failed 
/scratch/cphillim/hg/10ptr3/build/linux-x64/jdk/lib/server/libjvm.so, 
because libffi.so.5: cannot open shared object file: No such file or 
directory

I did a "yum install libffi" which seemed to succeed.

Help?
Coleen

>
> If you cannot test your patch on a given platform X, please let me know. I have access to every platform supported by OpenJDK except AIX/PPC.
>
> Thanks,
> Adrian
>
>> On Oct 15, 2017, at 12:41 AM, Roman Kennke <rkennke at redhat.com> wrote:
>>
>> The JEP to remove the Shark compiler has received exclusively positive feedback (JDK-8189173) on zero-dev. So here comes the big patch to remove it.
>>
>> What I have done:
>>
>> grep -i -R shark src
>> grep -i -R shark make
>> grep -i -R shark doc
>> grep -i -R shark doc
>>
>> and purged any reference to shark. Almost everything was straightforward.
>>
>> The only things I wasn't really sure of:
>>
>> - in globals.hpp, I re-arranged the KIND_* bits to account for the gap that removing KIND_SHARK left. I hope that's good?
>> - in relocInfo_zero.hpp I put a ShouldNotCallThis() in pd_address_in_code(), I am not sure it is the right thing to do. If not, what *would* be the right thing?
>>
>> Then of course I did:
>>
>> rm -rf src/hotspot/share/shark
>>
>> I also went through the build machinery and removed stuff related to Shark and LLVM libs.
>>
>> Now the only references in the whole JDK tree to shark is a 'Shark Bay' in a timezone file, and 'Wireshark' in some tests ;-)
>>
>> I tested by building a regular x86 JVM and running JTREG tests. All looks fine.
>>
>> - I could not build zero because it seems broken because of the recent Atomic::* changes
>> - I could not test any of the other arches that seemed to reference Shark (arm and sparc)
>>
>> Here's the full webrev:
>>
>> http://cr.openjdk.java.net/~rkennke/8171853/webrev.00/ <http://cr.openjdk.java.net/%7Erkennke/8171853/webrev.00/>
>>
>> Can I get a review on this?
>>
>> Thanks, Roman