Sfink/Draft - GC Pointer Handling: Difference between revisions

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 The rules are different for storing pointers on the heap (i.e., into structures that have been allocated with new or malloc.) Once again, you must arrange for any pointers to be (1) discovered during tracing and (2) updated by the moving GC. For the most part, the same mechanism is used for both -- when tracing, the GC is handed an indirect pointer through which the gcthing pointer is updated if needed. Many exceptional cases may arise, however:
- * The gcthing pointer value may be used to construct a hash code
+* The gcthing pointer value may be used to construct a hash code
- * The gcthing pointer value may be tagged
+* The gcthing pointer value may be tagged
- * The structure containing the pointer is sometimes allocated on the stack, sometimes on the heap
+* The structure containing the pointer is sometimes allocated on the stack, sometimes on the heap
 Also, persistent pointer updates may be subject to write barriers for incremental and/or generational GC, where any modification must be monitored to maintain various invariants. Basically, you can't add, remove, or change a heap-stored gcthing pointer without informing the GC about it. See https://developer.mozilla.org/En/SpiderMonkey/Internals/Garbage_collection for details.