benchmark/bm_hash_aref_sym*.rb: force static symbols

Dynamic symbols hash more slowly because they need extra method
dispatch in rb_any_hash.  I am not sure if dynamic symbols are
a realistic use case as hash keys, so this commit only
restores performance when comparing against versions of Ruby
which lack dsyms.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47854 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 12 insertions, 2 deletions

diff --git a/benchmark/bm_hash_aref_sym.rb b/benchmark/bm_hash_aref_sym.rb
index 54298ffc9e..f75d163fe6 100644
--- a/benchmark/bm_hash_aref_sym.rb
+++ b/benchmark/bm_hash_aref_sym.rb
@@ -1,4 +1,9 @@
 h = {}
-syms = ('a'..'z').to_a.map(&:to_sym)
+syms = ('a'..'z').to_a
+begin
+  syms = eval("%i[#{syms.join(' ')}]")
+rescue SyntaxError # <= 1.9.3
+  syms.map!(&:to_sym)
+end
 syms.each { |s| h[s] = s }
 200_000.times { syms.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_sym_long.rb b/benchmark/bm_hash_aref_sym_long.rb
index a9be4059e6..9dab8df7be 100644
--- a/benchmark/bm_hash_aref_sym_long.rb
+++ b/benchmark/bm_hash_aref_sym_long.rb
@@ -3,6 +3,11 @@ syms = %w[puts warn syswrite write stat bacon lettuce tomato
 some symbols in this array may already be interned  others should not be
 hash browns make good breakfast but not cooked using prime numbers
 shift for division entries delete_if keys exist?
-].map!(&:to_sym)
+]
+begin
+  syms = eval("%i[#{syms.join(' ')}]")
+rescue SyntaxError # <= 1.9.3
+  syms.map!(&:to_sym)
+end
 syms.each { |s| h[s] = s }
 200_000.times { syms.each { |s| h[s] } }