Side-exit on cfunc with -2 argc

lib/ruby_vm/mjit/insn_compiler.rb

@@ -1731,6 +1731,10 @@ module RubyVM::MJIT
         asm.incr_counter(:send_arity)
         return CantCompile
       end
+      if cfunc.argc == -2
+        asm.incr_counter(:send_cfunc_ruby_array_varg)
+        return CantCompile
+      end
 
       # Check interrupts before SP motion to safely side-exit with the original SP.
       jit_check_ints(jit, ctx, asm)

mjit_c.h

@@ -135,6 +135,7 @@ MJIT_RUNTIME_COUNTERS(
 
     send_cfunc_variadic,
     send_cfunc_too_many_args,
+    send_cfunc_ruby_array_varg,
 
     send_ivar,
     send_ivar_splat,

mjit_c.rb

@@ -1061,6 +1061,7 @@ module RubyVM::MJIT # :nodoc: all
       send_iseq_kw_splat: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_iseq_kw_splat)")],
       send_cfunc_variadic: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_cfunc_variadic)")],
       send_cfunc_too_many_args: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_cfunc_too_many_args)")],
+      send_cfunc_ruby_array_varg: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_cfunc_ruby_array_varg)")],
       send_ivar: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_ivar)")],
       send_ivar_splat: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_ivar_splat)")],
       send_ivar_opt_send: [CType::Immediate.parse("size_t"), Primitive.cexpr!("OFFSETOF((*((struct rb_mjit_runtime_counters *)NULL)), send_ivar_opt_send)")],