RFR(XS): 8145333: -XX:+EnableJVMCI -XX:+UseJVMCICompiler -XX:-EnableJVMCI makes JVM crash

[Christian Thalinger]

+  if (EnableJVMCI)
+    return true;

Please use { } for all if statements.

Thanks for the comments; it’s easier to understand now.  May I suggest to do:

  int skip_fail_count;  
  if (!FLAG_IS_DEFAULT(EnableJVMCI)) {
    skip_fail_count = 1;
  } else {
    skip_fail_count = 0;  
  }

> On Feb 18, 2016, at 6:26 AM, Jamsheed C m <jamsheed.c.m at oracle.com> wrote:
> 
> Hi Chris,
> 
> Made all suggested changes.
> 
> Revised webrev: http://cr.openjdk.java.net/~thartmann/8145333/webrev.04/ <http://cr.openjdk.java.net/~thartmann/8145333/webrev.04/>
> 
> Best Regards,
> Jamsheed
> 
> On 2/18/2016 6:24 AM, Jamsheed C m wrote:
>> 
>> 
>> On 2/18/2016 12:36 AM, Christian Thalinger wrote:
>>> 
>>>> On Feb 17, 2016, at 4:52 AM, Jamsheed C m < <mailto:jamsheed.c.m at oracle.com>jamsheed.c.m at oracle.com <mailto:jamsheed.c.m at oracle.com>> wrote:
>>>> 
>>>> experimental and diagnostic flags are under condition checks now.
>>>> 
>>>> http://cr.openjdk.java.net/~thartmann/8145333/webrev.03/ <http://cr.openjdk.java.net/%7Ethartmann/8145333/webrev.03/>
>>> 
>>> I’m not very happy about the new macros but I can see why it’s useful.
>>> 
>>> +#if INCLUDE_JVMCI
>>> +
>>> +// Check consistency of jvmci vm argument settings.
>>> +bool Arguments::check_jvmci_args_consistency() {
>>> + 
>>> +
>>> +  if (!EnableJVMCI && is_any_jvmci_arg_values_changed()) { 
>>> +    print_jvmci_arg_inconsistency_error_message(); 
>>> +    return false;
>>> 
>>> Please remove all these empty lines.  There are others as well.
>>> 
>>> +bool is_any_jvmci_arg_values_changed() {  
>>> 
>>> This method needs another name.
>>> 
>> Ok.
>>> +  int check_count = 0, fail_count = 0;
>>> 
>>> I don’t like the check_count/fail_count logic because it’s fragile.
>> As  EanbleJVMCI flag cannot be avoided from macro expansion logic, i had to use some technique to exclude this flag from failure decision making. 
>> Check_count/fail_count logic was added as a solution for this. i.e When EnableJVMCI is changed, code requires at-least 2 check failures to decide a real failure. otherwise one failure is sufficient. 
>>  
>> if i remove this logic, i will have to use strcmp(#FLAG, "EnableJVMCI") which will add a little more instructions that will  execute at-least once for every flag consistent run.
>> 
>> let me know if i need to take second approach. or if existing code is ok.
>>> 
>>> +// Check if any jvmci global defaults changed.
>>> +bool is_any_jvmci_arg_values_changed();
>>> +// Print jvmci args inconsistency error message.
>>> +void print_jvmci_arg_inconsistency_error_message();
>>> 
>>> These should be in some kind of namespace or class.  Maybe put them into: class JVMCIGlobals
>> Ok.
>> 
>> Best Regards,
>> Jamsheed
>>> 
>>>> 
>>>> 
>>>> Best Regards,
>>>> Jamsheed
>>>> 
>>>> On 2/16/2016 6:50 PM, Jamsheed C m wrote:
>>>>> Hi Chris,
>>>>> 
>>>>> Revised webrev: http://cr.openjdk.java.net/~thartmann/8145333/webrev.02/ <http://cr.openjdk.java.net/%7Ethartmann/8145333/webrev.02/>
>>>>> 
>>>>> This code take care of every jvmci flags automatically.
>>>>> 
>>>>> Best Regards,
>>>>> Jamsheed
>>>>> 
>>>>> On 2/13/2016 3:24 AM, Christian Thalinger wrote:
>>>>>> 
>>>>>>> On Feb 12, 2016, at 7:12 AM, Jamsheed C m <jamsheed.c.m at oracle.com <mailto:jamsheed.c.m at oracle.com>> wrote:
>>>>>>> 
>>>>>>> 
>>>>>>> Hi Chris,
>>>>>>> 
>>>>>>> On 2/12/2016 10:12 PM, Christian Thalinger wrote:
>>>>>>>> Well, now you have to manually check all flags that had a constraint directive.  That is the annoying part and what I complained about in:
>>>>>>> check against original value, and if not fail ?
>>>>>> 
>>>>>> Same check for all flags; they all depend on +EnableJVMCI.
>>>>>> 
>>>>>>>> 
>>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8145357 <https://bugs.openjdk.java.net/browse/JDK-8145357>
>>>>>>>> 
>>>>>>>> Also, commandLineFlagConstraintsJVMCI.{cpp,hpp} files are now empty and I think we should remove them.
>>>>>>> i kept the file as there can be future use. Ok, i will remove it.
>>>>>>> 
>>>>>>> Best Regards,
>>>>>>> Jamsheed
>>>>>>>> 
>>>>>>>>> On Feb 11, 2016, at 9:47 PM, Jamsheed C m < <mailto:jamsheed.c.m at oracle.com>jamsheed.c.m at oracle.com <mailto:jamsheed.c.m at oracle.com>> wrote:
>>>>>>>>> 
>>>>>>>>> Hi Chris,
>>>>>>>>> 
>>>>>>>>> revised webrev:  <http://cr.openjdk.java.net/%7Ethartmann/8145333/webrev.01/>http://cr.openjdk.java.net/~thartmann/8145333/webrev.01/ <http://cr.openjdk.java.net/~thartmann/8145333/webrev.01/>
>>>>>>>>> 
>>>>>>>>> Best Regards,
>>>>>>>>> Jamsheed
>>>>>>>>> 
>>>>>>>>> On 2/11/2016 11:31 PM, Christian Thalinger wrote:
>>>>>>>>>> 
>>>>>>>>>>> On Feb 11, 2016, at 3:47 AM, Jamsheed C m < <mailto:jamsheed.c.m at oracle.com>jamsheed.c.m at oracle.com <mailto:jamsheed.c.m at oracle.com>> wrote:
>>>>>>>>>>> 
>>>>>>>>>>> Hi,
>>>>>>>>>>> 
>>>>>>>>>>> Request for review
>>>>>>>>>>> 
>>>>>>>>>>> bug url:   <https://bugs.openjdk.java.net/browse/JDK-8145333>https://bugs.openjdk.java.net/browse/JDK-8145333 <https://bugs.openjdk.java.net/browse/JDK-8145333>
>>>>>>>>>>> web url:  <http://cr.openjdk.java.net/%7Ethartmann/8145333/webrev.00/>http://cr.openjdk.java.net/~thartmann/8145333/webrev.00/ <http://cr.openjdk.java.net/~thartmann/8145333/webrev.00/>
>>>>>>>>>> 
>>>>>>>>>> That looks alright but we should remove the constraints from all the JVMCI command line flags because the way we use them is not supported.
>>>>>>>>>> 
>>>>>>>>>> Also, can you change the error message?  Right now it looks like this:
>>>>>>>>>> 
>>>>>>>>>> $ ./build/macosx-x86_64-normal-server-release/jdk/bin/java -XX:+UnlockExperimentalVMOptions -XX:+UseJVMCICompiler
>>>>>>>>>> EnableJVMCI must be enabled
>>>>>>>>>> Improperly specified VM option 'UseJVMCICompiler'
>>>>>>>>>> Error: Could not create the Java Virtual Machine.
>>>>>>>>>> Error: A fatal exception has occurred. Program will exit.
>>>>>>>>>> 
>>>>>>>>>> I think with your changes we will only see the first line without mentioning UseJVMCICompiler.  Is that correct?
>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>>> Fix Summary: added jvmci flag consistency check after arg parsing.
>>>>>>>>>>> 
>>>>>>>>>>> tests: jprt
>>>>>>>>>>> unit test: command line verification
>>>>>>>>>>> 
>>>>>>>>>>> Best Regards,
>>>>>>>>>>> Jamsheed
>>>>>>>>>> 
>>>>>>>>> 
>>>>>>>> 
>>>>>>> 
>>>>>> 
>>>>> 
>>>> 
>>> 
>> 
> 

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