insns.def (opt_case_dispatch): avoid converting Infinity

Infinity cannot be written as an optimizable literal,
so it can never match a key in a CDHASH.
Avoid converting it to prevent FloatDomainError.

* insns.def (opt_case_dispatch): avoid converting Infinity
* test/ruby/test_optimization.rb (test_opt_case_dispatch_inf): new
  [ruby-dev:49423] [Bug #11804]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53039 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 11 insertions, 0 deletions

diff --git a/test/ruby/test_optimization.rb b/test/ruby/test_optimization.rb
index 1c50044f7f..3573d1267f 100644
--- a/test/ruby/test_optimization.rb
+++ b/test/ruby/test_optimization.rb
@@ -362,4 +362,15 @@ class TestRubyOptimization < Test::Unit::TestCase
       assert_redefine_method(k, '===', "assert_equal(#{v.inspect} === 0, 0)")
     end
   end
+
+  def test_opt_case_dispatch_inf
+    inf = 1.0/0.0
+    result = case inf
+             when 1 then 1
+             when 0 then 0
+             else
+               inf.to_i rescue nil
+             end
+    assert_nil result, '[ruby-dev:49423] [Bug #11804]'
+  end
 end