[bitc-dev] Unboxed polymorphic representations

[Sandro Magi]

Probably a little late now, but I just came across this work on unboxed
polymorphic representations that might serve as an interesting contrast
to specializing compilers like BitC:

An Unboxed Operational Semantics for ML Polymorphism
http://www.pllab.riec.tohoku.ac.jp/~ohori/research/jlsc97.pdf

I believe this technique is used in SML# [1], which is an SML
implementation extended with record polymorphism, rank-1 polymorphism,
and unboxed representations thus supporting natural interoperability with C.

One of the authors also developed an unboxed representation which lifts
the 1-bit tag into an external bitmask:

Compiling ML Polymorphism with Explicit Layout Bitmap
http://www.pllab.riec.tohoku.ac.jp/~ohori/research/NguyenOhoriPPDP06.pdf

Sandro

[1] http://www.pllab.riec.tohoku.ac.jp/smlsharp/