= SXMLSimplify

The optimization passes for the <<SXML#>> <<IntermediateLanguage#>> are
collected and controlled by the `SxmlSimplify` functor
(https://github.com/MLton/mlton/blob/master/mlton/xml/sxml-simplify.sig[`sxml-simplify.sig`],
https://github.com/MLton/mlton/blob/master/mlton/xml/sxml-simplify.fun[`sxml-simplify.fun`]).

The following optimization passes are implemented:

* <<Polyvariance#>>
* <<SXMLShrink#>>

The following implementation passes are implemented:

* <<ImplementExceptions#>>
* <<ImplementSuffix#>>

The following optimization passes are not implemented, but might prove useful:

* <<Uncurry#>>
* <<LambdaLift#>>

The optimization passes can be controlled from the command-line by the options

* `-diag-pass <pass>` -- keep diagnostic info for pass
* `-disable-pass <pass>` -- skip optimization pass (if normally performed)
* `-enable-pass <pass>` -- perform optimization pass (if normally skipped)
* `-keep-pass <pass>` -- keep the results of pass
* `-sxml-passes <passes>` -- sxml optimization passes
