RFR(S) 8234429: appcds/dynamicArchive tests crashing with Graal

[Ioi Lam]

Hi Calvin, Thanks for the review.

- Ioi

On 11/22/19 11:12 AM, Calvin Cheung wrote:
> Hi Ioi,
>
> The fix looks good.
>
> thanks,
>
> Calvin
>
> On 11/20/19 2:28 PM, Ioi Lam wrote:
>> https://bugs.openjdk.java.net/browse/JDK-8234429
>> http://cr.openjdk.java.net/~iklam/jdk14/8234429-dynamic-cds-graal-crash.v01/ 
>>
>>
>> In JDK-8231610, the implementation of DynamicArchive::is_mapped() is 
>> changed to
>>
>>     static bool is_mapped() { return FileMapInfo::dynamic_info() != 
>> NULL; }
>>
>> During dynamic dumping, we temporarily (inside a safepoint) allocate 
>> a dynamic FileMapInfo, which makes it appear as if the dynamic 
>> archive has been mapped.
>>
>> When graal is enabled, the VM actually continues to run for a little 
>> (compiling Java methods) after dynamic dumping has finished. During 
>> this time, when JVMCI tries to resolves a class, it might try to look 
>> up from the dynamic archive, which will fail as the dynamic archive 
>> isn't really mapped.
>>
>> The fix is to free the temporarily allocated FileMapInfo when dynamic 
>> dumping is finished.
>>
>> Thanks
>> - Ioi