RuntimeDyld is currently responsible for tracking allocated EH frames, but it makes more sense to have the RuntimeDyld::MemoryManager track them (since the frames are allocated through the memory manager, and written to memory owned by the memory manager). This patch moves the frame tracking into RTDyldMemoryManager, and changes the deregisterFrames method on RuntimeDyld::MemoryManager from:
void deregisterEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size);
Separating this responsibility will allow ORC to continue to throw the RuntimeDyld instances away post-link (saving a few dozen bytes per lazy function) while properly deregistering frames when modules are unloaded.
This patch also updates ORC to call deregisterEHFrames when modules are unloaded. This fixes a bug where an exception that tears down the JIT can then unwind through dangling EH frames that have been deallocated but not deregistered, resulting in UB.
For people using SectionMemoryManager this should be pretty much a no-op. For people with custom allocators that override registerEHFrames/deregisterEHFrames, you will now be responsible for tracking allocated EH frames.