[11] RFR jck test fails with C2: vm/jvmti/FollowReferences/fref001/fref00113/fref00113.html

[Paul Sandoz]

> On Jul 3, 2018, at 10:25 AM, coleen.phillimore at oracle.com wrote:
> 
> 
> 
> On 7/3/18 12:26 PM, Paul Sandoz wrote:
>> 
>>> On Jul 2, 2018, at 11:43 AM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
>>> 
>>> On 7/2/18 10:39 AM, Paul Sandoz wrote:
>>>> Hi,
>>>> Please review this fix for 11:
>>>>   http://cr.openjdk.java.net/~psandoz/jdk/JDK-8202769-ci-stream-cp-tag/webrev/
>>> Seems good to me. I will run testing with it.
>>> 
>> Thanks, i see all relevant tests pass, so ok to push?
> 
> You need two reviewers,

Ok.


> and are you pushing this to JDK11 ?
> 

Yes.


> The patch in the bug report seems better because you don't know that all of the callers want to convert JVM_CONSTANT_Dynamic to the underlying type that the Symbol points to.  The name of the ciStream function implies that it just returns tag_at().   I would assume that there would be other callers that want to do something with the actual tag, like print the bytecode stream for example.
> 

The patch in the bug report was a quick hack to get the test running by reverting what was pushed for constant dynamic support, but it will result in failures if it encounters a constant dynamic entry as the type of the dynamic constant is required and not JVM_CONSTANT_Dynamic.

The method ciBytecodeStream::get_constant_pool_tag is used for producing ldc instructions in what appears to be specialized cases, see the two usages in BCEscapeAnalyzer::iterate_one_block and Parse::do_one_bytecode.

We could rename it to Parse::get_constant_pool_tag_for_ldc ? if so would prefer to do that as a separate issue for 12 only.

Thanks,
Paul.

> Coleen
> 
>> 
>> Paul.
>