[12] RFR(S): 8214025: assert(t->singleton()) failed: must be a constant when ScavengeRootsInCode < 2

[Tobias Hartmann]

Hi,

please review the following patch:
https://bugs.openjdk.java.net/browse/JDK-8214025
http://cr.openjdk.java.net/~thartmann/8214025/webrev.00/

In Parse::do_call(), we try to create a constant for 'appendix_arg' but
TypeOopPtr::make_from_constant() does not return a singleton because with ScavengeRootsInCode <= 1,
ciObject::should_be_constant() is false. We need to pass require_const = true because this code
relies on a constant to be produced.

Thanks,
Tobias