Use shape information in YJIT's definedivar implementation (#7579)

* Use shape information in YJIT's definedivar implementation

* Handle complex shape for definedivar

1 files changed, 47 insertions, 0 deletions

diff --git a/bootstraptest/test_yjit.rb b/bootstraptest/test_yjit.rb
index 64203322c6..14ed13035d 100644
--- a/bootstraptest/test_yjit.rb
+++ b/bootstraptest/test_yjit.rb
@@ -79,6 +79,53 @@ assert_equal '[nil, nil, nil, nil, nil, nil]', %q{
   end
 }
 
+assert_equal '[nil, nil, nil, nil, nil, nil]', %q{
+  # Tests defined? on non-heap objects
+  [NilClass, TrueClass, FalseClass, Integer, Float, Symbol].each do |klass|
+    klass.class_eval("def foo = defined?(@foo)")
+  end
+
+  [nil, true, false, 0xFABCAFE, 0.42, :cake].map do |instance|
+    instance.foo
+    instance.foo
+  end
+}
+
+assert_equal '[nil, "instance-variable", nil, "instance-variable"]', %q{
+  # defined? on object that changes shape between calls
+  class Foo
+    def foo
+      defined?(@foo)
+    end
+
+    def add
+      @foo = 1
+    end
+
+    def remove
+      self.remove_instance_variable(:@foo)
+    end
+  end
+
+  obj = Foo.new
+  [obj.foo, (obj.add; obj.foo), (obj.remove; obj.foo), (obj.add; obj.foo)]
+}
+
+assert_equal '["instance-variable", 5]', %q{
+  # defined? on object too complex for shape information
+  class Foo
+    def initialize
+      100.times { |i| instance_variable_set("@foo#{i}", i) }
+    end
+
+    def foo
+      [defined?(@foo5), @foo5]
+    end
+  end
+
+  Foo.new.foo
+}
+
 assert_equal '0', %q{
   # This is a regression test for incomplete invalidation from
   # opt_setinlinecache. This test might be brittle, so