The CLI does support C-style unboxed union types, see Section 6.2: http://research.microsoft.com/~emeijer/Papers/CLR.pdf
Whether it provides *enough* control for the purposes of BitC I'm not sure. Sandro Jonathan S. Shapiro wrote: > Is it possible for BitC on CLI to satisfy the representation > requirements for unions? I don't believe so, and this strikes me as an > area where CLI can/should be improved. > > On Sat, Nov 15, 2008 at 12:31 AM, Eric Northup <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> wrote: > > Rodrigo Kumpera wrote: > > The naive approach to support generics by a CLR VM is to expand every > > instantiation and produce > > native code for all variations. This is far from optimal as the > > generated bloat usually interacts pretty bad > > with the icache. > > > > What the VMs support [1] is sharing code for all reference types, > > which expands to pretty much the same thing. > > For valuetypes this sharing is non-trivial so no VM does it. > The very first CLR VM to support generics actually did share code for > compatible (from the perspective of the GC's reference visitor) > structure types - see section 4.1 of > http://research.microsoft.com/projects/clrgen/generics.pdf . > > [...] > > BTW, I think BitC would map very well on top of the CLR given it had > > interface injection support. > I agree that a CLI target would be interesting for BitC. No particular > support for interface injection is necessary - I can imagine several > direct embeddings of type classes into CLI interfaces. Polyinstantation > or method dictionaries could also be done while targeting the CLI, thus > treating it as a lower-level IL. The lower-level IL might potentially > be compatible with the CIL subset supported by the gcc cli front-end. > > > I didn't quite understand what Shap said about sometimes needing to > dynamically fabricate a dictionary, though. Is that a consequence of > separate compilation? > _______________________________________________ > bitc-dev mailing list > [email protected] <mailto:[email protected]> > http://www.coyotos.org/mailman/listinfo/bitc-dev > > > > ------------------------------------------------------------------------ > > _______________________________________________ > bitc-dev mailing list > [email protected] > http://www.coyotos.org/mailman/listinfo/bitc-dev _______________________________________________ bitc-dev mailing list [email protected] http://www.coyotos.org/mailman/listinfo/bitc-dev
