KiSetTrapContext is an asm wrapper around RtlSetUnwindContext, which first stores an exception frame to assure that all non-volatile registers were put on the stack, then calls RtlSetUnwindContext to update their first saving positions on the stack and finally restore the exception frame to potentially load any updated registers, that haven't been saved elsewhere on the stack.
[REACTOS] Misc 64 bit fixes
* [NTOS:MM] Allow MEM_DOS_LIM in NtMapViewOfSection on x64 as well
* [NTOS:MM] Implement x64 version of MmIsDisabledPage
* [HAL] Remove obsolete code
* [NTOS:KE] Fix amd64 version of KeContextToTrapFrame and KeTrapFrameToContext
* [XDK] Fix CONTEXT_XSTATE definition
* [PCNET] Convert physical address types from pointers to PHYSICAL_ADDRESS