Support memory aliasing (#2954)

* Back to the origins: Make memory manager take guest PA rather than host address once again

* Direct mapping with alias support on Windows

* Fixes and remove more of the emulated shared memory

* Linux support

* Make shared and transfer memory not depend on SharedMemoryStorage

* More efficient view mapping on Windows (no more restricted to 4KB pages at a time)

* Handle potential access violations caused by partial unmap

* Implement host mapping using shared memory on Linux

* Add new GetPhysicalAddressChecked method, used to ensure the virtual address is mapped before address translation

Also align GetRef behaviour with software memory manager

* We don't need a mirrorable memory block for software memory manager mode

* Disable memory aliasing tests while we don't have shared memory support on Mac

* Shared memory & SIGBUS handler for macOS

* Fix typo + nits + re-enable memory tests

* Set MAP_JIT_DARWIN on x86 Mac too

* Add back the address space mirror

* Only set MAP_JIT_DARWIN if we are mapping as executable

* Disable aliasing tests again (still fails on Mac)

* Fix UnmapView4KB (by not casting size to int)

* Use ref counting on memory blocks to delay closing the shared memory handle until all blocks using it are disposed

* Address PR feedback

* Make RO hold a reference to the guest process memory manager to avoid early disposal

Co-authored-by: nastys <nastys@users.noreply.github.com>

ARMeilleure/Signal/NativeSignalHandler.cs

@@ -103,7 +103,7 @@ namespace ARMeilleure.Signal
                     // Unix siginfo struct locations.
                     // NOTE: These are incredibly likely to be different between kernel version and architectures.
 
-                    config.StructAddressOffset = 16; // si_addr
+                    config.StructAddressOffset = OperatingSystem.IsMacOS() ? 24 : 16; // si_addr
                     config.StructWriteOffset = 8; // si_code
 
                     _signalHandlerPtr = Marshal.GetFunctionPointerForDelegate(GenerateUnixSignalHandler(_handlerConfig));