fa7f7a4cab4 changed the jit-dispatch function signature used in the
orc_rt_lite_reoptimize_helper function, but jit-dispatch still takes a
raw data pointer and size argument.
Should fix the bug in
https://lab.llvm.org/buildbot/#/builders/169/builds/18319 and similar
builds.
Updates ExecutionSession::runJITDispatchHandler to take the argument
buffer for the function as a WrapperFunctionBuffer, rather than an
ArrayRef<char>.
This is a first step towards more efficient jit-dispatch handler calls:
1. Handlers can now be run as tasks, since they own their argument
buffer (so there's no risk of it being deallocated before they're run)
2. In in-process JIT setups, this will allow argument buffers to be
passed in directly from the ORC runtime, rather than having to copy the
buffer.
ReOptimizeLayer was building LLVM IR to define a precomputed,
SPS-serialized argument buffer, then inserting calls directly to
__orc_rt_jit_dispatch, passing the address of the precomputed buffer and
an __orc_rt_reoptimize_tag defined by the ORC runtime. This design is
non-canonical, requiring the ORC runtime to be loaded (or an extra
definition for __orc_rt_reoptimize_tag to be inserted) while not using
the runtime to perform the serialization.
This commit updates ReOptimizeLayer to instead insert calls to an
__orc_rt_reoptimize function implemented in the ORC runtime. This
function will perform serialization and call __orc_rt_jit_dispatch,
similar to other functions in the ORC runtime.
To maintain support for in-process JITs that don't use the ORC runtime,
this commit adds a ReOptimizeLayer::addOrcRTLiteSupport method which
injects IR to define __orc_rt_reoptimize (calling through to an
orc_rt_lite_reoptimize_helper function defined in LLVM) and
__orc_rt_reoptimize_tag. The ReOptimizeLayerTest is updated to use
addOrcRTLiteSupport.
