RFR: 8168295: [JVMCI] -XX:+JVMCIPrintProperties should exit after printing

[Christian Thalinger]

> On Oct 19, 2016, at 6:40 AM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
> 
> I thought it was intentional :)
> 
> Original output was similar to JVM flags output:

That was the whole point.

> 
>     bool UseCompressedOops     = true   {lp64_product} {ergonomic}
>     bool UseConcMarkSweepGC    = false  {product} {default}
> 
> But on other hand new output looks more clean and I like it.
> 
> thanks,
> Vladimir
> 
> On 10/19/16 6:55 AM, Doug Simon wrote:
>> Please review this small change that fixes an accidental omission from https://bugs.openjdk.java.net/browse/JDK-8167194. The -XX:+JVMCIPrintProperties flag should cause the VM to exit (like the -Djvmci.PrintFlags system property removed by 8167194 used to). Unlike -XX:+PrintFlagsFinal and -XX:+PrintFlagsInitial, it doesn’t make sense to continue execution after printing the help message triggered by -XX:+JVMCIPrintProperties.
>> 
>> Include in this patch is a minor change in the format of the help output to match that of Graal[1]. Instead of:
>> 
>> [JVMCI properties]
>>  String jvmci.Compiler                = null
>>         Selects the system compiler.
>> Boolean jvmci.InitTimer               = false
>>         Specifies if initialization timing is enabled.
>> Boolean jvmci.PrintConfig             = false
>>         Prints VM configuration available via JVMCI.
>>  String jvmci.TraceMethodDataFilter   = null
>>         Enables tracing of profiling info when read by JVMCI.
>>         Empty value: trace all methods
>>         Non-empty value: trace methods whose fully qualified name contains the value.
>> 
>> the output is now:
>> 
>> [JVMCI properties]
>> jvmci.Compiler = null                                                     [String]
>>          Selects the system compiler.
>> jvmci.InitTimer = false                                                  [Boolean]
>>          Specifies if initialization timing is enabled.
>> jvmci.PrintConfig = false                                                [Boolean]
>>          Prints VM configuration available via JVMCI.
>> jvmci.TraceMethodDataFilter = null                                        [String]
>>          Enables tracing of profiling info when read by JVMCI.
>>          Empty value: trace all methods
>>          Non-empty value: trace methods whose fully qualified name contains the value.
>> 
>> The new format makes it easier to scan the available options since the option name is not aligned with the help message.
>> 
>> 
>> http://cr.openjdk.java.net/~dnsimon/8168295/
>> https://bugs.openjdk.java.net/browse/JDK-8168295
>> 
>> -Doug
>> 
>> [1] https://github.com/graalvm/graal-core/commit/096f2fd304c6937623abc9483fc02862b4fa909e
>>