cuVS support for IDSelector APIs

[cjnolet]

This is a tracking issue to enable support for the IDSelector (e.g. pre-filtering) APIs through the cuVS indexes. We will contribute this feature, but want to have an issue to link.

[mdouze]

The IDSelector's only virtual function is is_member that returns a boolean.

On CPU, the indexes that support filtering at search time have two modes of operation:

1. call is_member for the ids and keep the result depending on the ouput
2. specialized behavior for certain types of IDSelectors, see this wiki entry.

I don't know how feasible it is to shell out from GPU to call a virtual function for the general case. But it would already be very useful to support a few simple IDSelector types on GPU like IDSelectorRange or IDSelectorBitmap

[cjnolet]

I don't know how feasible it is to shell out from GPU to call a virtual function for the general case.

@mdouze, yes we plan to support the bare IDSelector types (like range and bitmap) initially. Longer term we'd like to find a good way to express more generalized filters on device (potentially with the use of JIT).