RFR: 8245717: VM option "-XX:EnableJVMCIProduct" could not be repetitively enabled

[Xiaohong Gong]

Hi David,

 > On 26/05/2020 4:57 pm, Xiaohong Gong wrote:
 > > Hi,
 > >
 > > Could you please help to review this simple patch? It fixes the
 > issue
 > > that JVM crashes in debug mode when the vm option
 > "-XX:EnableJVMCIProduct" is enabled repetitively.
 > >
 > > JBS: https://bugs.openjdk.java.net/browse/JDK-8245717
 > > Webrev: http://cr.openjdk.java.net/~xgong/rfr/8245717/webrev.00/
 > >
 > > Repetitively enabling the vm option "-XX:+EnableJVMCIProduct" in
 > the
 > > command line makes the assertion fail in debug mode:
 > "assert(is_experimental(), sanity)".
 > >
 > > It happens when the VM iteratively parses the options from
 > command
 > > line. When the matched option is "-XX:+EnableJVMCIProduct", the
 > > original experimental JVMCI flags will be converted to product
 > mode,
 > > with the above assertion before it. So if all the JVMCI flags
 > have
 > > been converted to the product mode at the first time parsing
 > "-XX:+EnableJVMCIProduct", the assertion will fail at the second
 > time it is parsed.
 > >
 > > A simple fix is to just ignoring the conversion if this option
 > has been parsed.
 > 
 > Seems a reasonable approach given the already complex handling of
 > this flag.
 >
 > > Testing:
 > > Tested jtreg
 > > hotspot::hotspot_all_no_apps,jdk::jdk_core,langtools::tier1
 > > and jcstress:tests-custom, and all tests pass without new
 > failure.
 > 
 > I think adding a regression test in
 > ./compiler/jvmci/TestEnableJVMCIProduct.java would be appropriate.

Thanks for your review and it’s a good idea to add the regression test. 
I have added the test in the new patch:
http://cr.openjdk.java.net/~xgong/rfr/8245717/webrev.01/ .

Could you please take a look at it? Thank you!

Thanks,
Xiaohong Gong