refactor newhash (revision 58463 another try) [fix GH-1600]

	* st.c (rb_hash_bulk_insert): new API to bulk insert entries
	  into a hash. Given arguments are first inserted into the
	  table at once, then reindexed. This is faster than inserting
	  things using rb_hash_aset() one by one.

	  This arrangement (rb_ prefixed function placed in st.c) is
	  unavoidable because it both touches table internal and write
	  barrier at once.

	* internal.h: delcare the new function.

	* hash.c (rb_hash_s_create): use the new function.

	* vm.c (core_hash_merge): ditto.

	* insns.def (newhash): ditto.

	* test/ruby/test_hash.rb: more coverage on hash creation.

	* test/ruby/test_literal.rb: ditto.

-----------------------------------------------------------
benchmark results:
minimum results in each 7 measurements.
Execution time (sec)
name    before  after
loop_whileloop2  0.136  0.137
vm2_bighash*     1.249  0.623

Speedup ratio: compare with the result of `before' (greater is better)
name    after
loop_whileloop2 0.996
vm2_bighash*    2.004



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58492 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 29 insertions, 0 deletions

diff --git a/test/ruby/test_literal.rb b/test/ruby/test_literal.rb
index 28290fb19d..4a447d59fc 100644
--- a/test/ruby/test_literal.rb
+++ b/test/ruby/test_literal.rb
@@ -394,6 +394,35 @@ class TestRubyLiteral < Test::Unit::TestCase
     end;
   end
 
+  def test_hash_duplicated_key
+    h = EnvUtil.suppress_warning do
+      eval <<~end
+        # This is a syntax that renders warning at very early stage.
+        # eval used to delay warning, to be suppressible by EnvUtil.
+        {"a" => 100, "b" => 200, "a" => 300, "a" => 400}
+      end
+    end
+    assert_equal(2, h.size)
+    assert_equal(400, h['a'])
+    assert_equal(200, h['b'])
+    assert_nil(h['c'])
+    assert_equal(nil, h.key('300'))
+  end
+
+  def test_hash_frozen_key_id
+    key = "a".freeze
+    h = {key => 100}
+    assert_equal(100, h['a'])
+    assert_same(key, *h.keys)
+  end
+
+  def test_hash_key_tampering
+    key = "a"
+    h = {key => 100}
+    key.upcase!
+    assert_equal(100, h['a'])
+  end
+
   def test_range
     assert_instance_of Range, (1..2)
     assert_equal(1..2, 1..2)