[ORC] Break up OrcJIT library, add Orc-RPC based remote TargetProcessControl
This patch aims to improve support for out-of-process JITing using OrcV2. It
introduces two new class templates, OrcRPCTargetProcessControlBase and
OrcRPCTPCServer, which together implement the TargetProcessControl API by
forwarding operations to an execution process via an Orc-RPC Endpoint. These
utilities are used to implement out-of-process JITing from llvm-jitlink to
a new llvm-jitlink-executor tool.
This patch also breaks the OrcJIT library into three parts:
- OrcTargetProcess: Contains code needed by the JIT execution process.
- OrcShared: Contains code needed by the JIT execution and compiler processes
- OrcJIT: Everything else.
This break-up allows JIT executor processes to link against OrcTargetProcess
and OrcShared only, without having to link in all of OrcJIT. Clients executing
JIT'd code in-process should start linking against OrcTargetProcess as well as
In the near future these changes will enable:
- Removal of the OrcRemoteTargetClient/OrcRemoteTargetServer class templates which provided similar functionality in OrcV1.
- Restoration of Chapter 5 of the Building-A-JIT tutorial series, which will serve as a simple usage example for these APIs.
- Implementation of lazy, cross-target compilation in lli's -jit-kind=orc-lazy mode.