Review Request: JDK-8185148: [MVT] Class.java's isValueClass causes all non-MVT enabled JVM executions to have an InstanceKlass created for __Value reference
mandy.chung at oracle.com
Fri Jul 28 14:26:22 UTC 2017
One thing to mention:
Q_TYPE('Q', MinimalValueTypes_1_0.getValueClass(), Wrapper.OBJECT),
If value type is not enabled, Q_TYPE would have a null basic type Class.
I expect Q_TYPE should not be used in that case. Do you see any issue?
> On Jul 28, 2017, at 5:28 AM, Maurizio Cimadamore <maurizio.cimadamore at oracle.com> wrote:
> Looks great - thanks!
> On 28/07/17 05:56, Mandy Chung wrote:
>> A class referencing java.lang.__Value would fail verification when value type is not enabled. Class::isValueType and MinimalValueTypes_1_0::getValueType both references java.lang.__Value but they may be loaded when value type is not enabled. VerifyError that Tobias has ran into  is related to this issue.
>> A simple fix is to refactor the reference to java.lang.__Value in a separate class that will only be loaded when -XX:+EnableMVT and —XX:+EnableValhalla is set. We may look into a cleaner fix in the future.
>>  http://mail.openjdk.java.net/pipermail/valhalla-dev/2017-July/003007.html
More information about the valhalla-dev