This changes the interface to the ThreadIndices classes to have both
input and output indices. It also adds a visit index to ThreadIndices.
Also added the VisitIndex execution signature tag, which relies on this
behavior.
Previously, all Fetch objects received an Invocation object in their
Load and Store methods. The point of this was that it allowed the Fetch
to get data from any of the execution objects. However, every Fetch
either just got data directly from its associated execution object or
else used a secondary execution object (the input domain) to get indices
into their own execution object.
This left two potential areas for improvement. First, pulling data out
of the Invocation object was unnecessarily complicated. It would be much
nicer to get data directly from the associated execution object. Second,
when getting index information from the input domain, it was often the
case that extra computations were necessary (particularly on structured
cell sets). There was no way to share the index information among
Fetches, and therefore the computations were replicated.
This change removes the Invocation from the Fetch Load and Store.
Instead, it passes the associated execution object and a new object type
called the ThreadIndices. The ThreadIndices are customized for the input
domain and therefore have all the information needed for a redirected
lookup. It is also a thread-local object so it can cache computed
indices and save on computation time.
The ExecObject tag for the ControlSignature was not declared right so
would cause a compile error if it was ever used. Clearly this was not
being tested properly, so the dispatcher base unit test now passes an
ExecObject parameter.
It's easy to put accidently put something that is not a valid tag in a
ControlSignature or ExecutionSignature. Previously, when you did that
you got a weird error at the end of a very long template instantiation
chain that made it difficult to find the offending worklet.
This adds some type checks when the dispatcher is instantated to check
the signatures. It doesn't point directly to the signature or its
parameter, but it is much closer.
These changes support the implementation of DispatcherBase. This class
provides the basic functionality for calling an Invoke method in the
control environment, transferring data to the execution environment,
scheduling threads in the execution environment, pulling data for each
calling of the worklet method, and actually calling the worklet.
