1 files changed, 85 insertions, 0 deletions
diff --git a/bootstraptest/test_yjit.rb b/bootstraptest/test_yjit.rb
index 18d1f85b93..140365ee0c 100644
--- a/bootstraptest/test_yjit.rb
+++ b/bootstraptest/test_yjit.rb
@@ -1,3 +1,88 @@
+assert_equal '0', %q{
+  # This is a regression test for incomplete invalidation from
+  # opt_setinlinecache. This test might be brittle, so
+  # feel free to remove it in the future if it's too annoying.
+  # This test assumes --yjit-call-threshold=2.
+  module M
+    Foo = 1
+    def foo
+      Foo
+    end
+
+    def pin_self_type_then_foo
+      _ = @foo
+      foo
+    end
+
+    def only_ints
+      1 + self
+      foo
+    end
+  end
+
+  class Integer
+    include M
+  end
+
+  class Sub
+    include M
+  end
+
+  foo_method = M.instance_method(:foo)
+
+  dbg = ->(message) do
+    return # comment this out to get printouts
+
+    $stderr.puts RubyVM::YJIT.disasm(foo_method)
+    $stderr.puts message
+  end
+
+  2.times { 42.only_ints }
+
+  dbg["There should be two versions of getinlineache"]
+
+  module M
+    remove_const(:Foo)
+  end
+
+  dbg["There should be no getinlinecaches"]
+
+  2.times do
+    42.only_ints
+  rescue NameError => err
+    _ = "caught name error #{err}"
+  end
+
+  dbg["There should be one version of getinlineache"]
+
+  2.times do
+    Sub.new.pin_self_type_then_foo
+  rescue NameError
+    _ = 'second specialization'
+  end
+
+  dbg["There should be two versions of getinlineache"]
+
+  module M
+    Foo = 1
+  end
+
+  dbg["There should still be two versions of getinlineache"]
+
+  42.only_ints
+
+  dbg["There should be no getinlinecaches"]
+
+  # Find name of the first VM instruction in M#foo.
+  insns = RubyVM::InstructionSequence.of(foo_method).to_a
+  if defined?(RubyVM::YJIT.blocks_for) && (insns.last.find { Array === _1 }&.first == :opt_getinlinecache)
+    RubyVM::YJIT.blocks_for(RubyVM::InstructionSequence.of(foo_method))
+      .filter { _1.iseq_start_index == 0 }.count
+  else
+    0 # skip the test
+  end
+}
+
 # Check that frozen objects are respected
 assert_equal 'great', %q{
   class Foo