NameTest::matches is a very hot spot
in saxon. Profiling shows that most
of its runtime is spent doing virtual
method dispatch on NodeInfo#getNodeKind
We optimise this by making a base class
with the node kind as a field.
Also, we now pool xpath names using saxon's
name pool, which reduces name tests to
integer comparison instead of string.equals
Saxon now spends 80x less time in the name test
overall shaving off 30% of execution time of
XPath rules.
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