RFR (S) 8176580: [ppc, s390] CRC32C: wrong checksum result in some cases
Zoltán Majó
zoltan.majo at oracle.com
Wed Apr 12 12:38:17 UTC 2017
Hi Lutz,
On 04/12/2017 02:14 PM, Schmidt, Lutz wrote:
> Hi Zoltan,
>
> First of all: thanks for trying to push! Second: sorry for the problems you ran into.
you are welcome and no problem, of course.
> I do not have an immediate explanation for the failure – my dev machine is MacOS/x86_64. I will try to reproduce immediately. For the time being: is there any log output that could shed some light on the issue?
Please find the output below (and sorry for not including it before).
Please let me know if you were able to reproduce the problem (or not).
Best regards,
Zoltan
command: main -Xbatch compiler.intrinsics.zip.TestCRC32C -m
reason: User specified action: run main/othervm/timeout=600 -Xbatch compiler.intrinsics.zip.TestCRC32C -m
Mode: othervm [/othervm specified]
elapsed time (seconds): 1.915
configuration:
STDOUT:
testing 1050 cases ...
STDERR:
ERROR: crc = 6f894393, crcReference = 2cdf6e8f
java.lang.Exception: TestCRC32C Error
at compiler.intrinsics.zip.TestCRC32C.check(TestCRC32C.java:218)
at compiler.intrinsics.zip.TestCRC32C.test_multi(TestCRC32C.java:280)
at compiler.intrinsics.zip.TestCRC32C.main(TestCRC32C.java:74)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:563)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:110)
at java.base/java.lang.Thread.run(Thread.java:844)
JavaTest Message: Test threw exception: java.lang.Exception: TestCRC32C Error
JavaTest Message: shutting down test
STATUS:Failed.`main' threw exception: java.lang.Exception: TestCRC32C Error
>
> Thanks,
> Lutz
>
>
> On 12.04.2017, 13:10, "hotspot-compiler-dev on behalf of Zoltán Majó" <hotspot-compiler-dev-bounces at openjdk.java.net on behalf of zoltan.majo at oracle.com> wrote:
>
> P.S.: Forgot to mention: The problem does not appear on any other x86_64
> platform.
>
> On 04/12/2017 01:07 PM, Zoltán Majó wrote:
> > Hi Volker,
> > Hi Lutz,
> >
> >
> > yesterday I tried to push webrev.03 using JPRT. Unfortunately, the
> > TestCRC32C.java test you've modified fails on Mac OS X on x86_64. Do
> > you have an idea why that could be?
> >
> > Thank you! Best regards,
> >
> >
> > Zoltan
> >
> > On 04/11/2017 06:03 PM, Volker Simonis wrote:
> >> Thanks a lot Zoltan!
> >>
> >>
> >> On Tue, Apr 11, 2017 at 4:35 PM, Zoltán Majó <zoltan.majo at oracle.com
> >> <mailto:zoltan.majo at oracle.com>> wrote:
> >>
> >> Hi Volker,
> >>
> >>
> >> On 04/11/2017 03:34 PM, Volker Simonis wrote:
> >>
> >>
> >> Hi Zoltan,
> >>
> >> could you please be so kind to sponsor this reviewed change
> >> for jdk10?
> >>
> >>
> >> yes, of course. I'll push it today.
> >>
> >> Best regards,
> >>
> >>
> >> Zoltan
> >>
> >> Initially we wanted to push it ourselves because it was s390x
> >> only but now that we've also touched the tests we need a
> >> sponsor.
> >>
> >> Thank you and best regards,
> >> Volker
> >>
> >> ---------- Forwarded message ----------
> >> From: *Volker Simonis* <volker.simonis at gmail.com
> >> <mailto:volker.simonis at gmail.com>
> >> <mailto:volker.simonis at gmail.com
> >> <mailto:volker.simonis at gmail.com>>>
> >> Date: Fri, Mar 31, 2017 at 10:53 AM
> >> Subject: Re: RFR (S) 8176580: [ppc, s390] CRC32C: wrong
> >> checksum result in some cases
> >> To: "Schmidt, Lutz" <lutz.schmidt at sap.com
> >> <mailto:lutz.schmidt at sap.com> <mailto:lutz.schmidt at sap.com
> >> <mailto:lutz.schmidt at sap.com>>>
> >> Cc: Andrew Haley <aph at redhat.com <mailto:aph at redhat.com>
> >> <mailto:aph at redhat.com <mailto:aph at redhat.com>>>,
> >> "hotspot-compiler-dev at openjdk.java.net
> >> <mailto:hotspot-compiler-dev at openjdk.java.net>
> >> <mailto:hotspot-compiler-dev at openjdk.java.net
> >> <mailto:hotspot-compiler-dev at openjdk.java.net>>"
> >> <hotspot-compiler-dev at openjdk.java.net
> >> <mailto:hotspot-compiler-dev at openjdk.java.net>
> >> <mailto:hotspot-compiler-dev at openjdk.java.net
> >> <mailto:hotspot-compiler-dev at openjdk.java.net>>>
> >>
> >>
> >> Ping...
> >>
> >> Can somebody please push this change?
> >>
> >> It's ppc64/s390x only but as a courtesy to the community it
> >> also fixes
> >> the CRC JTreg tests so unfortunately I still can't push it
> >> myself :)
> >>
> >> Thank you and best regards,
> >> Volker
> >>
> >>
> >> On Tue, Mar 28, 2017 at 5:01 PM, Volker Simonis
> >> <volker.simonis at gmail.com <mailto:volker.simonis at gmail.com>
> >> <mailto:volker.simonis at gmail.com
> >> <mailto:volker.simonis at gmail.com>>> wrote:
> >> > Hi Lutz,
> >> >
> >> > thanks a lot for fixing the test!
> >> > Your change looks good now.
> >> >
> >> > Because this touches shared (i.e. test) files, we still need
> >> a sponsor
> >> > so can somebody please sponsor this change?
> >> >
> >> > Thank you and best regards,
> >> > Volker
> >> >
> >> >
> >> >
> >> > On Fri, Mar 24, 2017 at 4:54 PM, Schmidt, Lutz
> >> <lutz.schmidt at sap.com <mailto:lutz.schmidt at sap.com>
> >> <mailto:lutz.schmidt at sap.com <mailto:lutz.schmidt at sap.com>>>
> >> wrote:
> >> >> Hi Volker,
> >> >>
> >> >> Sorry for letting you wait. Here is the final(?) webrev,
> >> containing all your requests for cleanup and improvements:
> >> >> http://cr.openjdk.java.net/~lucy/webrevs/8176580.03/
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.03/>
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.03/
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.03/>>
> >> >>
> >> >> As before, the *.cpp files have not been modified.
> >> >>
> >> >> Best Regards,
> >> >> Lutz
> >> >>
> >> >>
> >> >>
> >> >> On 21/03/2017, 17:55, "Volker Simonis"
> >> <volker.simonis at gmail.com <mailto:volker.simonis at gmail.com>
> >> <mailto:volker.simonis at gmail.com
> >> <mailto:volker.simonis at gmail.com>>> wrote:
> >> >>
> >> >> Hi Lutz,
> >> >>
> >> >> thanks a lot for updating the tests. I think they look
> >> much better now.
> >> >>
> >> >> There's just one more cleanup I'd like to propose. Can
> >> you please move
> >> >> the throw right into the check() function. Just make
> >> check() return
> >> >> void and throw from it if there's a mismatch between
> >> the computed and
> >> >> the expected result. I leave it up to you if you want
> >> to pass an extra
> >> >> error string to check() which will be printed in the
> >> case of an error.
> >> >> I personally don't think that's necessary as it will be
> >> evident from
> >> >> the stack trace which computation failed.
> >> >>
> >> >> Also the try/catch and rethrow in test_multi() isn't
> >> necessary. The
> >> >> test can be simply terminated by the initial exception.
> >> >>
> >> >> Thank you and best regards,
> >> >> Volker
> >> >>
> >> >>
> >> >> On Fri, Mar 17, 2017 at 10:03 PM, Schmidt, Lutz
> >> <lutz.schmidt at sap.com <mailto:lutz.schmidt at sap.com>
> >> <mailto:lutz.schmidt at sap.com <mailto:lutz.schmidt at sap.com>>>
> >> wrote:
> >> >> > Hi Volker,
> >> >> >
> >> >> > Thanks a lot for your valuable hints.
> >> >> >
> >> >> > I have worked some time on the Java test files:
> >> >> > TestCRC32.java and TestCRC32C.java are now
> >> identical as far as possible.
> >> >> > They now throw an exception, should any error be
> >> detected.
> >> >> > The “reference CRC value” is now used in
> >> test_multi() as well.
> >> >> > The extra test runs have been removed again.
> >> >> > The test methodology is fixed: each result is
> >> tested against its reference.
> >> >> > The tests now detect the bug introduced with
> >> 8175368 and 8175369.
> >> >> > No issue is indicated when testing with 8176580.
> >> >> > I ran jcheck, and to the best of my ability and
> >> knowledge, there is no trailing whitespace.
> >> >> > All *.cpp files were left untouched!
> >> >> >
> >> >> > The next iteration of the webrev:
> >> http://cr.openjdk.java.net/~lucy/webrevs/8176580.02/
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.02/>
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.02/
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.02/>>
> >> >> >
> >> >> > Best regards,
> >> >> > Lutz
> >> >> >
> >> >> >
> >> >> > Dr. Lutz Schmidt | SAP JVM | PI SAP CP Core | T: +49
> >> (6227) 7-42834 <tel:%2B49%20%286227%29%207-42834>
> >> <tel:%2B49%20%286227%29%207-42834>
> >> >> >
> >> >> >
> >> >> >
> >> >> > On 16.03.17, 11:28, "Volker Simonis"
> >> <volker.simonis at gmail.com <mailto:volker.simonis at gmail.com>
> >> <mailto:volker.simonis at gmail.com
> >> <mailto:volker.simonis at gmail.com>>> wrote:
> >> >> >
> >> >> > On Wed, Mar 15, 2017 at 5:55 PM, Schmidt, Lutz
> >> <lutz.schmidt at sap.com <mailto:lutz.schmidt at sap.com>
> >> <mailto:lutz.schmidt at sap.com <mailto:lutz.schmidt at sap.com>>>
> >> wrote:
> >> >> > >
> >> >> > > Hi Andrew, Volker,
> >> >> > >
> >> >> > > What do you think about these test enhancements?
> >> >> > > Webrev:
> >> http://cr.openjdk.java.net/~lucy/webrevs/8176580.01/
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.01/>
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.01/
> >> <http://cr.openjdk.java.net/%7Elucy/webrevs/8176580.01/>>
> >>
> >> >> > >
> >> >> > > Please note: the cpp files in the webrev
> >> remained unchanged.
> >> >> > >
> >> >> > > I added some improvements (as I believe) to the
> >> TestCRC32(C).java files.
> >> >> > >
> >> >> > > In some more detail:
> >> >> > > The test now calculates a “reference CRC
> >> value”, based on a java implementation of the CRC32 algorithm.
> >> This reference value is used to verify all other crc values,
> >> in particular during initialization and warmup. Three
> >> additional test runs check a non-zero offset with –Xint,
> >> -Xcomp -XX:-TieredCompilation (C2 only), -Xcomp
> >> -XX:+TieredCompilation (C1 + C2).
> >> >> > >
> >> >> >
> >> >> > Hi Lutz,
> >> >> >
> >> >> > thanks for updating the tests. I've had a closer
> >> look at the tests and
> >> >> > realized that they actually can never fail! The
> >> check() routine just
> >> >> > prints an error message but that will not let the
> >> test fail. So I
> >> >> > would suggest to throw a runtime exception in the
> >> check() routine
> >> >> > after the error message was printed.
> >> >> >
> >> >> > I also suggest to do the check during the normal
> >> test execution (i.e.
> >> >> > in test_multi()) so there's no need for extra
> >> test runs.
> >> >> >
> >> >> > Finally, the current test methodology in
> >> test_multi() is broken:
> >> >> > - it sets the reference by calling CRC from the
> >> interpreter which
> >> >> > won't work if the intrinsic is also used in the
> >> interpreter.
> >> >> > - it only compares the reference against the
> >> last computation of CRC
> >> >> > in the loop which will be the result of the C2
> >> generated code. This
> >> >> > misses errors in C1.
> >> >> >
> >> >> > I suggest to use your new, pure Java
> >> implementation for the
> >> >> > computation of the reference result and compare
> >> the reference with the
> >> >> > result of calling CRC in every iteration of the
> >> loop so we really
> >> >> > check all possibilities from interpreter trough
> >> C1 to C2.
> >> >> >
> >> >> > Finally, can you please pay attention to not
> >> insert trailing
> >> >> > whitespace (there was some at line 88 in
> >> TestCRC32C.java). You can
> >> >> > easily verify this by running jcheck before
> >> creating the webrevs.
> >> >> >
> >> >> > Thanks,
> >> >> > Volker
> >> >> >
> >> >> > >
> >> >> > > Best regards,
> >> >> > > Lutz
> >> >> > >
> >> >> > >
> >> >> > > On 15.03.17, 11:50, "Volker Simonis"
> >> <volker.simonis at gmail.com <mailto:volker.simonis at gmail.com>
> >> <mailto:volker.simonis at gmail.com
> >> <mailto:volker.simonis at gmail.com>>> wrote:
> >> >> > >
> >> >> > > On Tue, Mar 14, 2017 at 7:05 PM, Andrew
> >> Haley <aph at redhat.com <mailto:aph at redhat.com>
> >> <mailto:aph at redhat.com <mailto:aph at redhat.com>>> wrote:
> >> >> > > > On 14/03/17 13:12, Schmidt, Lutz wrote:
> >> >> > > >
> >> >> > > >> Yes, one might think of running a test
> >> suite subset multiple times
> >> >> > > >> with different parameters. In this case,
> >> -Xint and/or –Xcomp were
> >> >> > > >> helpful. Forcing tests to run fully
> >> interpreted or fully compiled
> >> >> > > >> helps in cases where a certain function,
> >> e.g. an intrinsic, is
> >> >> > > >> invoked via distinct code paths.
> >> >> > > >
> >> >> > > > Right, so your patch should include that
> >> change to the test suite.
> >> >> > > >
> >> >> > >
> >> >> > > Hi Lutz,
> >> >> > >
> >> >> > > I agree with Andrew. We should really fix
> >> the tests such that they
> >> >> > > check the correctness of the intrinsics.
> >> >> > >
> >> >> > > This may be tricky if all three, the
> >> interpreter, the client and the
> >> >> > > server compiler use the same intrinsic
> >> implementation. You could
> >> >> > > either copy the pure Java implementation
> >> into the test so that you can
> >> >> > > compare the results of the intrinsic
> >> operation against it or you can
> >> >> > > switch them off in the compilers with
> >> >> > > "-XX:DisableIntrinsic=_updateBytesCRC32C
> >> >> > >
> >> -XX:DisableIntrinsics=_updateDirectByteBufferCRC32C" and
> >> compare the
> >> >> > > results. Not sure which solution is more
> >> practical, but I would be
> >> >> > > really scared if we wouldn't have these test.
> >> >> > >
> >> >> > > Regards,
> >> >> > > Volker
> >> >> > >
> >> >> > > > Andrew.
> >> >> > > >
> >> >> > >
> >> >> > >
> >> >> >
> >> >> >
> >> >>
> >> >>
> >>
> >>
> >>
> >
>
>
>
More information about the hotspot-compiler-dev
mailing list