Fix stackmap always marking ConstantDynamic as objects

[fengxue-IS]

• Check Condy return type before marking stack slot

Signed-off-by: Jack Lu Jack.S.Lu@ibm.com

[gacholio]

I'd like @DanHeidinga to have a look before merge.

[DanHeidinga]

I'm OK with this.

An alternative approach would have been to switch on the J9DescriptionReturnTypeShift types and assert on the long/double cases but the corresponding bytecodes already have that assert in place. I think we're ok without adding it here

[DanHeidinga]

@fengxue-IS It would be good to add tests for this case or identify a JTREG that already covers it

[gacholio]

This issue will be difficult to reproduce with random tests - the condy value needs to be on the pending stack when a GC occurs.

Something like:

func(condyValue, gc())

where the gc() method forces some GCs before returning.

[gacholio]

Should be easy enough to craft the above test and see that it crashes every time without the fix from this PR.

[fengxue-IS]

I will look into adding a test case for this

[gacholio]

@DanHeidinga Does the verifier need a similar change, or is it already there?

[DanHeidinga]

@DanHeidinga Does the verifier need a similar change, or is it already there?

Verifier already does it correctly - see rtverify.c:
https://github.com/eclipse/openj9/blob/10d5686ffabe19806fc71bd3ea42ddbe9e99fdae/runtime/bcverify/rtverify.c#L720-L726

which pushes the ldc type using:
https://github.com/eclipse/openj9/blob/10d5686ffabe19806fc71bd3ea42ddbe9e99fdae/runtime/bcverify/vrfyhelp.c#L420-L425

[DanHeidinga]

Jenkins test sanity zlinux jdk11

[fengxue-IS]

@DanHeidinga can you please restart the PR build, looks like it failed due to network issue

[2020-03-06T18:26:29.903Z] Cannot contact rh7-390-4: java.lang.InterruptedException
[2020-03-06T18:35:50.499Z] wrapper script does not seem to be touching the log file in /home/jenkins/workspace/Build_JDK11_s390x_linux_Personal@tmp/durable-c2ff9402
[2020-03-06T18:35:50.499Z] (JENKINS-48300: if on an extremely laggy filesystem, consider -Dorg.jenkinsci.plugins.durabletask.BourneShellScript.HEARTBEAT_CHECK_INTERVAL=86400)

[DanHeidinga]

Jenkins test sanity zlinux jdk11

[DanHeidinga]

Jenkins test sanity zlinux jdk11

[DanHeidinga]

ported to 0.19 release in #877