This looks like we're just swapping the positions of capEPBadge and capEPPtr,
but it turns out that the bitwise op being performed on capEPPtr to set the
high bits were part of the data dependency critical path, so this actually
does improve the speed by moving the bitwise op to capEPBadge (albeit it's
now an AND instead of an OR)
I initially set the field size to 32 bits, but it turns out that causes gcc
to emit an instruction (mov r32, r32) that causes the instruction decoder
to switch to the legacy decode path for the rest of the fast path for some
reason.
This is a *breaking API change*
This commit:
* makes seL4_Fault_tag_t common between the kernel and libsel4
* deprecates the existing functions from sel4/messages.h includes
* introduces a new fault API in sel4/faults.h and
* sel4/sel4_arch/faults.h
* deprecates seL4_GetTag(), as the function did not work without
the user calling seL4_SetTag() first (seL4_MessageInfo is passed
in registers and not set in the IPC buffer)
* removes previously deprecated functions (deprecated prior to 3.0.0)
* updates the seL4 manual to reflect the changes