Compiled methods need to perform a null check in the unverified entry. This is usually done implicitely by loading the Klass*.
However, implicit null checks may be off on PPC64 (especially on AIX where the 0 page is readable).

Null checks are especially needed after:
8160543: C1: Crash in java.lang.String.indexOf in some java.sql tests
Summary: C1 must use unverified entry point for unloaded methods.