Function rustc_mir::shim::build_call_shim

fn build_call_shim<'tcx>(
    tcx: TyCtxt<'tcx>, 
    instance: InstanceDef<'tcx>, 
    rcvr_adjustment: Option<Adjustment>, 
    call_kind: CallKind<'tcx>, 
    untuple_args: Option<&[Ty<'tcx>]>
) -> Body<'tcx>

Builds a "call" shim for instance. The shim calls the function specified by call_kind, first adjusting its first argument according to rcvr_adjustment.

If untuple_args is a vec of types, the second argument of the function will be untupled as these types.