new benchmarks for hashing dsyms and fixnums

* benchmark/bm_hash_aref_dsym.rb: new benchmark
* benchmark/bm_hash_aref_dsym_long.rb: ditto
* benchmark/bm_hash_aref_fix.rb: ditto

[ruby-core:70129] [Bug #11396] pointed out we need to consider
more cases for hashing.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51435 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Thu Jul 30 04:29:25 2015  Eric Wong  <e@80x24.org>
+
+	* benchmark/bm_hash_aref_dsym.rb: new benchmark
+	* benchmark/bm_hash_aref_dsym_long.rb: ditto
+	* benchmark/bm_hash_aref_fix.rb: ditto
+
 Wed Jul 29 21:38:41 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* hash.c (any_hash), symbol.c (dsymbol_alloc): fix dynamic symbol

benchmark/bm_hash_aref_dsym.rb

@@ -0,0 +1,4 @@
+h = {}
+syms = ('a'..'z').map { |s| s.to_sym }
+syms.each { |s| h[s] = 1 }
+200_000.times { syms.each { |s| h[s] } }

benchmark/bm_hash_aref_dsym_long.rb

@@ -0,0 +1,21 @@
+# [ruby-core:70129] [Bug #11396]
+collection_size = 200000
+sample_size = 10000
+
+values = (1..collection_size).to_a.map do |x|
+  "THIS IS A LONGER STRING THAT IS ALSO UNIQUE #{x}"
+end
+
+symbol_hash = {}
+
+values.each do |x|
+  symbol_hash[x.to_sym] = 1
+end
+
+# use the same samples each time to minimize deviations
+rng = Random.new(0)
+symbol_sample_array = values.sample(sample_size, random: rng).map(&:to_sym)
+
+3000.times do
+  symbol_sample_array.each { |x| symbol_hash[x] }
+end

benchmark/bm_hash_aref_fix.rb

@@ -0,0 +1,4 @@
+h = {}
+nums = (1..26).to_a
+nums.each { |i| h[i] = i }
+200_000.times { nums.each { |s| h[s] } }