Fix invokebuiltin in Ruby MJIT

https://github.com/ruby/ruby/blob/45fe7f757522ed7d1d3ec754da59d41d45dd6bab/tool/ruby_vm/views/_mjit_compile_invokebuiltin.erb#L21
has not been ported correctly.

lib/mjit/compiler.rb

@@ -446,9 +446,10 @@ def compile_ivar(insn_name, stack_size, pos, status, operands, body)
     def compile_invokebuiltin(f, insn, stack_size, sp_inc, body, operands)
       bf = C.RB_BUILTIN.new(operands[0])
       if bf.compiler > 0
+        index = (insn.name == :invokebuiltin ? -1 : operands[1])
         C.fprintf(f, "{\n")
         C.fprintf(f, "    VALUE val;\n")
-        C.builtin_compiler(f, bf, operands[1], stack_size, body.builtin_inline_p)
+        C.builtin_compiler(f, bf, index, stack_size, body.builtin_inline_p)
         C.fprintf(f, "    stack[#{stack_size + sp_inc - 1}] = val;\n")
         C.fprintf(f, "}\n")
         return true

test/ruby/test_mjit.rb

@@ -24,9 +24,6 @@ class TestMJIT < Test::Unit::TestCase
     # not supported yet
     :defineclass,
 
-    # to be tested
-    :invokebuiltin,
-
     # never used
     :opt_invokebuiltin_delegate,
   ].each do |insn|
@@ -600,6 +597,15 @@ def test_compile_insn_opt_regexpmatch2
     assert_compile_once("'true' =~ /true/", result_inspect: '0', insns: %i[opt_regexpmatch2])
   end
 
+  def test_compile_insn_invokebuiltin
+    iseq = eval(EnvUtil.invoke_ruby(['-e', <<~'EOS'], '', true).first)
+      p RubyVM::InstructionSequence.of([].method(:sample)).to_a
+    EOS
+    insns = collect_insns(iseq)
+    mark_tested_insn(:invokebuiltin, used_insns: insns)
+    assert_eval_with_jit('print [].sample(1)', stdout: '[]', success_count: 1)
+  end
+
   def test_compile_insn_opt_invokebuiltin_delegate_leave
     iseq = eval(EnvUtil.invoke_ruby(['-e', <<~'EOS'], '', true).first)
       p RubyVM::InstructionSequence.of("\x00".method(:unpack)).to_a