The change in (JDK-8366214) to simplify comparing objects causes several jaxp tranform tests to fail when --enable-preview is selected.

14:35:40.875] test transform.TransformerTest$Test8169112.run(): failure [97ms]
javax.xml.transform.TransformerConfigurationException: Not targeting 66542: nop[0](1), but null
	at java.xml/com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:1067)
	at java.xml/com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTransformer(TransformerFactoryImpl.java:824)
	at transform.util.TransformerTestTemplate.getTransformer(TransformerTestTemplate.java:135)
	at transform.util.TransformerTestTemplate.getTransformer(TransformerTestTemplate.java:121)
	at transform.TransformerTest$Test8169112.run(TransformerTest.java:585)

In JDK-8366214, HashMap was changed to use Objects.equals.
An Objects.equals was changed (in JDK-8366841) was changed to not use `==` (an identity comparison) when --enable-preview option is on the command line.
The TransformerTest fails with --enable-preview.

This change to HashMap exposes a flaw in the ..equals comparison of InstructionComparator.equals that does not return true of identical BranchInstructions.