insns.def: add opt path for Hash#[] and Hash#[]= used with str literal keys

* insns.def (opt_aref_with): new instruction to optimize Hash#[],
  removing any allocation overhead when used with a string literal
  key. Patch by normalperson (Eric Wong). [ruby-core:59640] [Bug #9382]
* insns.def (opt_aset_with): new instruction to optimize Hash#[]=
* compile.c (iseq_compile_each): compiler shortcuts for new
  instructions
* hash.c (static VALUE rb_hash_compare_by_id_p): fix documentation for
  Hash#compare_by_identity to reflect frozen string sharing
* test/ruby/test_hash.rb (class TestHash): test for new behavior

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44551 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 15 insertions, 1 deletions

diff --git a/test/ruby/test_hash.rb b/test/ruby/test_hash.rb
index 3861fde0a4..c39cd23d54 100644
--- a/test/ruby/test_hash.rb
+++ b/test/ruby/test_hash.rb
@@ -209,6 +209,20 @@ class TestHash < Test::Unit::TestCase
     assert_equal(256,     h[z])
   end
 
+  def test_AREF_fstring_key
+    h = {"abc" => 1}
+    before = GC.stat(:total_allocated_object)
+    5.times{ h["abc"] }
+    assert_equal before, GC.stat(:total_allocated_object)
+  end
+
+  def test_ASET_fstring_key
+    a, b = {}, {}
+    assert_equal 1, a["abc"] = 1
+    assert_equal 1, b["abc"] = 1
+    assert_same a.keys[0], b.keys[0]
+  end
+
   def test_NEWHASH_fstring_key
     a = {"ABC" => :t}
     b = {"ABC" => :t}
@@ -946,7 +960,7 @@ class TestHash < Test::Unit::TestCase
     h = @cls[]
     h.compare_by_identity
     h["a"] = 1
-    h["a"] = 2
+    h["a".dup] = 2
     assert_equal(["a",1], h.assoc("a"))
   end