RFR: 8316694: Implement relocation of nmethod within CodeCache [v3]

[Vladimir Kozlov]

On Fri, 30 May 2025 22:51:53 GMT, Chad Rakoczy <duke at openjdk.org> wrote:

>> Actually even **mutable** is not critical since we did not include oops data section (we keep it with nmethod). It currently contains relocations, metadata (klass*, method*) and JVMCI data. We can experiment in separate RFE if we can use separate class for it too.
>
> I have created a RFE to move the immutable data from the nmethod to a separate class. [JDK-8358213](https://bugs.openjdk.org/browse/JDK-8358213)

Thanks.  Let's keep current changes as it is with small comment:
 IMMUTABLE_DATA_REFERENCES is used with `sizeof()` in all places - consider using instead 
 ```
 #define IMMUTABLE_DATA_REFERENCES_SIZE sizeof(int)
 ```

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/23573#discussion_r2116857046