TODO

TODO:
   Finish adding the rest of the MMX/SSE instructions and you'll be done!
   Check latest Intel docs and AMD docs for any new instructions that might
   have been added.
TODO:
   There's a lot of redundant code in the X86 core, specifically related to
   register assignment and such. Can you reduce that down to macros to provide
   more concise readable code that's less redundant?
TODO:
   Consider modifications to x86_core where the FPU decoding instead produces an 11-bit
   "opcode" which can be fed to a x87_core.h or whatever, thus segregating FPU and CPU
   instructions and FPU decoding can be done with a large efficient switch() statement.
TODO:
   When full x86-32 decoding is implemented, port decoding over to x86-64 core. Or better
   yet, find a way to conditionally include x86-64 decoding in x86_core.h
TODO:
   Remove superfluous seg_can_override() use now that x86_core.h sets all argv[] segments
   to DS by default
TODO:
   Eugh! AMD has their own "VEX" variation that re-uses illegal encodings of opcode 0x8F
   (rather than Intel-style illegal encodings of LDS/LES). Same register names though, i
   mplement AMD "XOP" decoding.