RFR(s): 8236042: [TESTBUG] serviceability/sa/ClhsdbCDSCore.java fails with -Xcomp -XX:TieredStopAtLevel=1

[Fairoz Matte]

Thanks Vladimir for the review.

Thanks for mentioning the reasons for MDO's not being generated, I have added them as comment in bug for future reference.

Thanks,
Fairoz

> -----Original Message-----
> From: Vladimir Kozlov
> Sent: Saturday, July 11, 2020 5:36 AM
> To: Fairoz Matte <fairoz.matte at oracle.com>; Chris Plummer
> <chris.plummer at oracle.com>; hotspot-compiler-dev at openjdk.java.net;
> serviceability-dev at openjdk.java.net
> Subject: Re: RFR(s): 8236042: [TESTBUG] serviceability/sa/ClhsdbCDSCore.java
> fails with -Xcomp -XX:TieredStopAtLevel=1
> 
> Fix is good.
> 
> I think next are reasons you don't get MDO in this scenario.
> 
> Tier1 (C1 compilation) does not generate profiling code and does not created
> MDO. C1 request MDO only with tiers 2 and 3 [1][2].
> 
> With -Xcomp flag a Java method is not executed in Interpreter but requests its
> compilation and waits when it is finished. As result MDO is not created in
> Interpreter too. May be late if a method is deoptimized it will be executed in
> Interpreter and MDO will be created.
> 
> Thanks,
> Vladimir
> 
> [1]
> http://hg.openjdk.java.net/jdk/jdk/file/796c9fa50850/src/hotspot/share/c1/c1_
> Compilation.hpp#l226
> [2]
> http://hg.openjdk.java.net/jdk/jdk/file/796c9fa50850/src/hotspot/share/c1/c1_
> Compilation.cpp#l381
> 
> On 7/7/20 8:47 PM, Fairoz Matte wrote:
> > Thanks Chris, for the review comments.
> >
> > I have updated the suggested change.
> >
> > Thanks,
> > Fairoz
> >
> >> -----Original Message-----
> >> From: Chris Plummer
> >> Sent: Wednesday, July 8, 2020 3:38 AM
> >> To: Fairoz Matte <fairoz.matte at oracle.com>; hotspot-compiler-
> >> dev at openjdk.java.net; serviceability-dev at openjdk.java.net
> >> Subject: Re: RFR(s): 8236042: [TESTBUG]
> >> serviceability/sa/ClhsdbCDSCore.java
> >> fails with -Xcomp -XX:TieredStopAtLevel=1
> >>
> >> Hi Fairoz,
> >>
> >> Looks good, except for the missing space in "if(testJavaOpts...".
> >>
> >> thanks,
> >>
> >> Chris
> >>
> >> On 7/7/20 7:49 AM, Fairoz Matte wrote:
> >>> Hi,
> >>>
> >>> Please review this small test change to consider the scenario when
> >>> there is no
> >> "printmdo" output
> >>>
> >>> JBS - https://bugs.openjdk.java.net/browse/JDK-8236042
> >>> Webrev - http://cr.openjdk.java.net/~fmatte/8236042/webrev.00/
> >>>
> >>> Thanks,
> >>> Fairoz
> >>