RFR(S): 8212673: jtreg/applications/runthese/RunThese30M.java fails in C2 with "assert(!had_error) failed: bad dominance"

[Roland Westrelin]

> After JDK-8213487 has been pushed I rebased and re-ran tier1-3 with 
> Rolands patch, and still see a number of failures where 
> compiler/gcbarriers/EqvUncastStepOverBarrier.java throws 
> "java.lang.RuntimeException: Method compilation failed".
>
> Reproducible with:
>
> $ make run-test TEST=compiler/gcbarriers/EqvUncastStepOverBarrier.java 
> JTREG="VM_OPTIONS=-XX:CompileThreshold=100"
>
> and:
>
> $ make run-test TEST=compiler/gcbarriers/EqvUncastStepOverBarrier.java 
> JTREG="VM_OPTIONS=-XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI 
> -XX:+TieredCompilation -XX:+UseJVMCICompiler -Djvmci.Compiler=graal"

Thanks for testing. Most likely the test doesn't support running with
CompileThreshold=100. Let me see how I can work around that.

Roland.