Adds support for both synchronous and asynchronous calls to wrapper functions
using SPS (Simple Packed Serialization). Also adds support for wrapping
functions on the JIT side in SPS-based wrappers that can be called from the
executor.
These new methods simplify calls between the JIT and Executor, and will be used
in upcoming ORC runtime patches to enable communication between ORC and the
runtime.
Replace the existing WrapperFunctionResult type in
llvm/include/ExecutionEngine/Orc/Shared/TargetProcessControlTypes.h with a
version adapted from the ORC runtime's implementation.
Also introduce the SimplePackedSerialization scheme (also adapted from the ORC
runtime's implementation) for wrapper functions to avoid manual serialization
and deserialization for calls to runtime functions involving common types.