Version 4 (modified by chak, 10 years ago) (diff)


Implementation notes for closure conversion


Almost all of the code concerning closure conversion is in the module ClosureConv in the directory vectorise/. This module exports the function closureConvert, which is invoked as part of the core-to-core passes right after the desugarer if the option fclosure-conv is provided.

Actual conversion

There is a separate description of the conversion scheme. This abstract description uses the convention that the existance of an Id, TyCon, or dataCon name followed by _CC indicates whether we have a closure converted variant of the corresponding declaration. In the concrete implementation this information is maintained in UniqFMs.

Cross-module information

The vectorisation information relevant across individual modules is maintained as values of type HscTypes.VectInfo and HscTypes.IfaceVectInfo. The former is the representation in HscTypes.ModGuts and the HscTypes.ExternalPackageState; the latter is used in HscTypes.ModIface.

In the ExternalPackageState, we use the same approach to combine the VectInfo of the various modules from the eps_PIT in a single table as is used for class instances, family instances, and rules. The corresponding field in ExternalPackageState is eps_vect_info::!PackageVectInfo. The information in this field is extended by LoadIface.loadInterface along with the corresponding fields for instances and rules.

TODO hptVectInfo and use of that.