These definitions are used to "augment" information received from the remote
target with eh/debug frame and "generic" register numbers.
Besides being verbose, this information was also incomplete (new registers like
xmm16-31 were missing) and sometimes even downright wrong (ymm register
numbers).
Most of this information is available via llvm's MCRegisterInfo. This patch
creates a new class, MCBasedABI, which retrieves the eh and debug frame register
numbers this way. The tricky part here is that the llvm class uses all-caps
register names, whereas lldb register are lowercase, and sometimes called
slightly differently. Therefore this class introduces some hooks to allow a
subclass to customize the MC lookup. The subclass also needs to suply the
"generic" register numbers, as this is an lldb invention.
This patch ports the x86_64 ABI classes to use the new register info mechanism.
It also creates a new "ABIx86_64" class which can be used to house code common
to x86_64 both ABIs. Right now, this just consists of a single function, but
there are plenty of other things that could be moved here too.
Typo? It should be uppercase, I think.