[Lldb-commits] [PATCH] D78978: [LLDB] Add support for WebAssembly debugging

[Paolo Severini via Phabricator via lldb-commits]

paolosev created this revision.
paolosev added reviewers: labath, clayborg.
paolosev added a project: LLDB.
Herald added subscribers: lldb-commits, sunfish, aheejin, jgravelle-google, sbc100, aprantl, mgorny, dschuff.
paolosev edited the summary of this revision.

This patch is a refactoring of  https://reviews.llvm.org/D78801. As suggested, I have created a separate patch to more easily compare the implementations.
Even here, the goal is to use the GDB-remote protocol to connect to a Wasm engine that implements a GDB-remote stub that offers the ability to access the engine runtime internal state.

Here I am removing the interface IWasmProcess and the new class WasmProcessGDBRemote and moving most of the Wasm logic in `ProcessGDBRemote`.
I am still adding the new Unwind class `UnwindWasm`, which now however is in core and not in plugins code.  Having a Unwind-derived class for Wasm unwinding seems to be the cleanest solution.

The advantage with this new design is that the required changes are smaller and isolated in a few places.
The drawback is that three 'core' classes (UnwindWasm, Value and DWARFExpression) have now a dependency on ProcessGDBRemote and/or ThreadGDBRemote. This could be avoided re-introducing a core interface like IWasmProcess. We could add a couple of virtual method  `bool IsWasmProcess()` and `IWasmProcess* AsWasmProcess()` to Process, which would be overridden by ProcessGDBRemote. Then these classes could just query this interface, removing direct dependencies on GDBRemote.

I am also adding a new `qSupported` flag named "wasm" that should tell LLDB whether the remote supports Wasm debugging.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D78978

Files:
  lldb/include/lldb/Target/UnwindWasm.h
  lldb/source/Core/Value.cpp
  lldb/source/Expression/DWARFExpression.cpp
  lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
  lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
  lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
  lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
  lldb/source/Target/CMakeLists.txt
  lldb/source/Target/Thread.cpp
  lldb/source/Target/UnwindWasm.cpp

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