_mjit_compile_send.erb: inline attr_reader call

_mjit_compile_send_guard.erb: carve out the shared logic to invalidate
inlined method call

common.mk: update dependency for this change

test_jit.rb: add test for attr_reader optimization

* Benchmark

```
require 'benchmark_driver'

Benchmark.driver do |x|
  x.prelude %{
    class C
      attr_reader :a
      def initialize
        @a = 1
      end
    end

    o = C.new

    def l o
      i = 0
      while i < 1000000
        o.a
        i += 1
      end
    end
  }
  x.report 'aread', %{ l o }
  x.loop_count 1000

  x.rbenv 'before', 'before,--jit', 'after,--jit'
  x.verbose
end
```

```
before: ruby 2.6.0dev (2018-04-20 trunk 63211) [x86_64-linux]
before,--jit: ruby 2.6.0dev (2018-04-20 trunk 63211) +JIT [x86_64-linux]
after,--jit: ruby 2.6.0dev (2018-04-20 trunk 63211) +JIT [x86_64-linux]
last_commit=_mjit_compile_send.erb: inline attr_reader call
Calculating -------------------------------------
                         before  before,--jit  after,--jit
               aread     54.597       122.894      218.574 i/s -      1.000k times in 18.316102s 8.137089s 4.575106s

Comparison:
                            aread
         after,--jit:       218.6 i/s
        before,--jit:       122.9 i/s - 1.78x  slower
              before:        54.6 i/s - 4.00x  slower

```

* Optcarrot

A little made faster?

fps: 71.35 -> 72.11

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63212 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 35 insertions, 0 deletions

diff --git a/test/ruby/test_jit.rb b/test/ruby/test_jit.rb
index f67c8a243c..9b80a90838 100644
--- a/test/ruby/test_jit.rb
+++ b/test/ruby/test_jit.rb
@@ -529,6 +529,41 @@ class TestJIT < Test::Unit::TestCase
     end;
   end
 
+  def test_attr_reader
+    assert_eval_with_jit("#{<<~"begin;"}\n#{<<~"end;"}", stdout: "4nil\nnil\n6", success_count: 2, min_calls: 2)
+    begin;
+      class A
+        attr_reader :a, :b
+
+        def initialize
+          @a = 2
+        end
+
+        def test
+          a
+        end
+
+        def undefined
+          b
+        end
+      end
+
+      a = A.new
+      print(a.test * a.test)
+      p(a.undefined)
+      p(a.undefined)
+
+      # redefinition
+      class A
+        def test
+          3
+        end
+      end
+
+      print(2 * a.test)
+    end;
+  end
+
   private
 
   # The shortest way to test one proc