It is possible to configure the build process such that decoding of 32
bit and 64 bit instructions can be chosen at runtime using an additional
parameter of the decode function. The header file is now entirely
architecture-independent and no longer required any previous defines.
Decoding x86-64 still requires a 64-bit pointer size.
As there is not much difference between the two mnemonic tables, it is
possible to unify them. As a consequence, the instruction types no
longer differ between 32 and 64 bit decodings.
