The buffer class encapsulates the movement of raw C arrays between
host and devices.
The `Buffer` class itself is not associated with any device. Instead,
`Buffer` is used in conjunction with a new templated class named
`DeviceAdapterMemoryManager` that can allocate data on a given
device and transfer data as necessary. `DeviceAdapterMemoryManager`
will eventually replace the more complicated device adapter classes
that manage data on a device.
The code in `DeviceAdapterMemoryManager` is actually enclosed in
virtual methods. This allows us to limit the number of classes that
need to be compiled for a device. Rather, the implementation of
`DeviceAdapterMemoryManager` is compiled once with whatever compiler
is necessary, and then the `RuntimeDeviceInformation` is used to
get the correct object instance.
Fixes#277
DeviceAdapterError existed to make sure that the default device adapter
template was being handled properly. Since the default device adapter doesn't
exist, and nothing is templated over it we can now remove DeviceAdapterError.
The RuntimeDeviceTracker had grown organically to handle multiple
different roles inside VTK-m. Now that we have device tags
that can be passed around at runtime, large portions of
the RuntimeDeviceTracker API aren't needed.
Additionally the RuntimeDeviceTracker had a dependency on knowing
the names of each device, and this wasn't possible
as that information was part of its self. Now we have moved that
information into RuntimeDeviceInformation and have broken
the recursion.
By making RuntimeDeviceInformation class template independent, vtkm is
able to detect
device info at runtime with a runtime specified deviceId. In the past
it's impossible
because the CRTP pattern does not allow function overloading(compiler
would complain
that DeviceAdapterRuntimeDetector does not have Exists() function
defined).