Fix gymrat disasm

[xxr0ss]

The disassemble() doesn't work because GymratLifter._lift() doesn't receive its args, which are not passed through Lifter.lift()

class GymratLifter(Lifter):
    ...
    def _lift(self, disassemble=False, dump_irsb=False):

and disasm result isn't returned from Lifter.lift(), which returns self.irsb instead of self._lift():

class Lifter:
    ...
    def lift(
        self,
        data,
        bytes_offset=None,
        max_bytes=None,
        max_inst=None,
        opt_level=1,
        traceflags=None,
        allow_arch_optimizations=None,
        strict_block_end=None,
        skip_stmts=False,
        collect_data_refs=False,
        cross_insn_opt=True,
        load_from_ro_regions=False,
    )
        ...
        self._lift()
        return self.irsb

I think lift() should return IRSB only because of its sematic, however GymratLifter (as well as many other code not listed here) also uses _lift() to return disassembly. Well, let's allow that.

[twizmwazin]

I'm not a fan of this solution, instead I would rather make the gymrat options be explicit kwargs on lift() instead and have them set as instance variables to be optionally read in _lift, just like the many libvex-specific args.

[xxr0ss]

@twizmwazin I agree. Let's just override the lift()!

[twizmwazin]

No, you misunderstand. lift should not be overridden, and _lift is private and should never be called by users of a lifter class. In the base Lifter class, we can add extra kwargs for the gymrat lifter, like how there are already many extra kwargs for the libvex lifter. These extra kwargs can be set on self, and then the _lift in the gymrat lifter can read them.

[xxr0ss]

@twizmwazin thanks for the detailed explanation!