JDK-8316694 adds a function that allows for relocation of nmethods within the code cache. This however causes issues for JVMCI nmethods that contain Java mirrors called HotSpotNMethods. These mirrors hold data about the nmethod such as address, code start, and entry point. After relocation the mirror fields must be updated to reflect the new nmethod. Some sort of concurrency control is required as Graal could deoptimize the nmethod we are relocating which sets the fields to zero. If relocation occurs at the same time as this and attempts to set the fields to a non zero values it could lead to undefined behavior

Nmethods with a mirror were excluded from relocation until this issue is completed.