On Darwin systems, the dynamic linker dyld has an empty function
it calls when binaries are added/removed from the process. lldb puts
a breakpoint on this dyld function to catch the notifications. The
function arguments are used by lldb to tell what is happening.
The linker has a natural representation when the addresses of
binaries being added/removed are in the pointer size of the process.
There is then a second function where the addresses of the binaries
are in a uint64_t array, which the debugger has been using before -
dyld allocates memory for the array, copies the values in to it,
and calls it for lldb's benefit.
This changes to using the native notifier function, with pointer-sized
addresses.
Differential Revision: https://reviews.llvm.org/D139453
624813a4f4