HotSpot 16 and OpenJDK6

Wed Feb 24 10:03:46 PST 2010

On 24 February 2010 16:42, Joseph D. Darcy <Joe.Darcy at sun.com> wrote:
> Joseph D. Darcy wrote:
>>
>> Joe Darcy wrote:
>>>
>>> Andrew John Hughes wrote:
>>>>
>>>> On 24 February 2010 00:28, Joe Darcy <Joe.Darcy at sun.com> wrote:
>>>>
>>>>>
>>>>> Andrew John Hughes wrote:
>>>>>
>>>>>>
>>>>>> On 23 February 2010 20:10, Joseph D. Darcy <Joe.Darcy at sun.com> wrote:
>>>>>>
>>>>>>
>>>>>>>
>>>>>>> Hello.
>>>>>>>
>>>>>>> Andrew John Hughes wrote:
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> Here's the merge:
>>>>>>>>
>>>>>>>> http://cr.openjdk.java.net/~andrew/jdk6-hs16-merge/webrev.01/
>>>>>>>>
>>>>>>>> which now builds, thanks to this additional changeset from Daniel
>>>>>>>> Daugherty in baseline:
>>>>>>>> http://hg.openjdk.java.net/hsx/hsx16/baseline/rev/c9740f5ed5b4
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>> Good.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> It also includes an additional fix, also listed separately at:
>>>>>>>>
>>>>>>>> http://cr.openjdk.java.net/~andrew/jdk6-hs16-merge/webrev.02/
>>>>>>>>
>>>>>>>> which reverts an erroneous change from SIZE_FORMAT to %d in
>>>>>>>>
>>>>>>>> changeset:   734:dbbe28fc66b5
>>>>>>>> user:        twisti
>>>>>>>> date:        Fri Feb 27 03:35:40 2009 -0800
>>>>>>>> summary:     6778669: Patch from Red Hat -- fixes compilation errors
>>>>>>>>
>>>>>>>> fixing the build on x86_64.  We'll need a bug ID for this reversion.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>> The webrev generally looks good, but I have a few questions and
>>>>>>> comments
>>>>>>> before this goes back.
>>>>>>>
>>>>>>> Do you know why webrev shows so many files with zero changes?  I
>>>>>>> assume
>>>>>>> this
>>>>>>> is an artifact of the merge.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> No, you're right that does seem strange.  All I did was a pull from
>>>>>> hs16 and then a merge.  Perhaps this is some webrev oddity?
>>>>>>
>>>>>> If you look at
>>>>>>
>>>>>> http://mail.openjdk.java.net/pipermail/jdk6-dev/2010-February/001230.html
>>>>>> I included a diff of the merged OpenJDK6 against the hs16 master
>>>>>> (which includes Daniel's patch that is currently only in baseline).
>>>>>> It actually makes the other questions below a bit clearer.
>>>>>>
>>>>>>
>>>>>
>>>>> Yes, that patch size is more manageable!
>>>>>
>>>>>
>>>>>>>
>>>>>>> In hotspot_version, what are the semantics of JDK_PREVIOUS_VERSION?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> I'm not sure.  It doesn't seem to do much.  Its only use is to set a
>>>>>> default BOOTDIR AFAICS:
>>>>>>
>>>>>> # Find JDK used for javac compiles
>>>>>>
>>>>>>
>>>>>> BOOTDIR=$(SLASH_JAVA)/re/j2se/$(PREVIOUS_JDK_VERSION)/latest/binaries/$(PLATFORM)
>>>>>>
>>>>>> (from hotspot/make/defs.make)
>>>>>>
>>>>>> We actually differ from hs16 by still using 1.5.0 rather than 1.6.0.
>>>>>> 1.5.0 implicitly seems to make more sense to me, because 1.6.0 is the
>>>>>> version being built.  But in practice, it doesn't seem to matter
>>>>>> unless you're relying on the contents of a /java tree.
>>>>>>
>>>>>>
>>>>>
>>>>> I have a vague recollection of there being a particular reason why this
>>>>> was
>>>>> upgraded to 1.6.0 so I'd prefer to see this kept as 1.6.0.
>>>>>
>>>>>
>>>>>>>
>>>>>>> In terms of fixing the %d vs SIZE_FORMAT in vmError.cpp, I've filed
>>>>>>> 6929005
>>>>>>> "Fix format specifier in vmError.cpp."  However, I notice that the
>>>>>>> JDK 7
>>>>>>> master still has %d in this location.  I'll approve going back from
>>>>>>> %d ->
>>>>>>> SIZE_FORMAT in OpenJDK 6 conditional on the review and approval of a
>>>>>>> HotSpot
>>>>>>> engineer.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> Interesting; I didn't check OpenJDK7 and indeed you're right.  Looking
>>>>>> again at the diff, it seems that we don't apply part of the same
>>>>>> changeset:
>>>>>>
>>>>>> --- ../hs16/src/share/vm/utilities/vmError.hpp  2010-01-13
>>>>>> 14:35:26.651211783 +0000
>>>>>> +++ hotspot/src/share/vm/utilities/vmError.hpp  2010-02-17
>>>>>> 11:07:40.899854566 +0000
>>>>>> @@ -50,7 +50,7 @@
>>>>>>
>>>>>>  // additional info for VM internal errors
>>>>>>  const char * _filename;
>>>>>> -  int          _lineno;
>>>>>> +  size_t       _lineno;
>>>>>>
>>>>>>  // used by fatal error handler
>>>>>>  int          _current_step;
>>>>>>
>>>>>> keeping the size_t rather than using int.  So I'll change the fix to
>>>>>> be making vmError.hpp match hs16 and OpenJDK7, rather than changing
>>>>>> vmError.cpp.
>>>>>>
>>>>>> The remaining diffs are typos and license fixups from the previous
>>>>>> merge which need to go back to the main HotSpot tree.
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>> If vmError.hpp matches what is in JDK 7 and HS 16, I approve your merge
>>>>> of
>>>>> HS 16 + Dan's fixes into OpenJDK 6.
>>>>>
>>>>>
>>>>
>>>> Pushed.  I reused 6929005 as Fix HS16 merge issues in OpenJDK 6 to
>>>> make vmError.hpp and JDK_PREVIOUS_VERSION match hs16.  You should
>>>> probably update the bug itself to match :-)
>>>>
>>>>
>>>
>>> A fine use for that bug id; content of the bug adjusted accordingly :-)
>>>
>>> -Joe
>>
>> Hmm, after syncing my repos and doing a build, I see test 2 HotSpot
>> regression test failures
>>
>>   * compiler/6823453/Test.java : DeoptimizeALot causes fastdebug server
>> jvm to fail with assert(false,"unscheduable graph")
>>   * compiler/6833129/Test.java : Object.clone() and Arrays.copyOf ignore
>> coping with -XX:+DeoptimizeALot
>>
>> both complaining of an unrecognized +DeoptimizeALot option.
>>
>> -Joe
>
> PS Some more testing results, after the HS update all the langtools tests
> continue to pass and the jdk repo results are about the same.
>
> -Joe
>

Backported: http://hg.openjdk.java.net/jdk6/jdk6/hotspot/rev/b13f90e8e0e5
I took the opportunity to fix the author of the changeset and move
cfang to Reviewed-by as it should have been in the first place:
http://mail.openjdk.java.net/pipermail/hotspot-dev/2009-September/002150.html

Great to hear that the results are good!  We did some testing with
hs16 on IcedTea6 a while back and it improved the HotSpot results
IIRC.

I look into backporting Zero once I've fixed some issues with IcedTea
and have it building OpenJDK6 hg.
-- 
Andrew :-)

Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

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