ZJIT: Specialize send with param_rest

[k0kubun]

On erubi-rails,

Top-20 send fallback reasons (100.0% of total 1,679,667):
                             invokeblock_not_specialized: 617,810 (36.8%)
                            one_or_more_complex_arg_pass: 321,562 (19.1%)
                          send_without_block_no_profiles: 277,692 (16.5%)
                          send_without_block_polymorphic: 213,232 (12.7%)
  send_without_block_not_optimized_method_type_optimized:  56,086 ( 3.3%)
                                   too_many_args_for_lir:  53,183 ( 3.2%)
                                        send_polymorphic:  24,226 ( 1.4%)

Next to invokeblock_not_specialized, one_or_more_complex_arg_pass is the #2 fallback reason.

Top-7 popular complex argument-parameter features not optimized (100.0% of total 361,616):
         param_rest: 184,347 (51.0%)
    caller_blockarg:  95,923 (26.5%)
  param_forwardable:  39,884 (11.0%)
       caller_splat:  31,298 ( 8.7%)
       caller_kwarg:   9,973 ( 2.8%)
       param_kwrest:     130 ( 0.0%)
    caller_kw_splat:      61 ( 0.0%)

param_rest accounts for 51% of one_or_more_complex_arg_pass on erubi-rails.

TODO

1. Specialize send with param_rest, allocating an array for the rest parameter
2. Investigate whether there are array allocations we can optimize away if the caller and the callee are inlined
3. Consider optimizing away such array allocation
   • We need to make sure the array doesn't escape