[lldb] Introduce ScriptedFrame affordance (#149622)

This patch introduces a new scripting affordance in lldb:
`ScriptedFrame`.

This allows user to produce mock stackframes in scripted threads and
scripted processes from a python script.

With this change, StackFrame can be synthetized from different sources:
- Either from a dictionary containing a load address, and a frame index,
  which is the legacy way.
- Or by creating a ScriptedFrame python object.

One particularity of synthezising stackframes from the ScriptedFrame
python object, is that these frame have an optional PC, meaning that
they don't have a report a valid PC and they can act as shells that just
contain static information, like the frame function name, the list of
variables or registers, etc. It can also provide a symbol context.

rdar://157260006

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

1 files changed, 59 insertions, 0 deletions

diff --git a/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedFramePythonInterface.h b/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedFramePythonInterface.h
new file mode 100644
index 000000000000..3aff237ae65d
--- /dev/null
+++ b/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedFramePythonInterface.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_PLUGINS_SCRIPTINTERPRETER_PYTHON_INTERFACES_SCRIPTEDFRAMEPYTHONINTERFACE_H
+#define LLDB_PLUGINS_SCRIPTINTERPRETER_PYTHON_INTERFACES_SCRIPTEDFRAMEPYTHONINTERFACE_H
+
+#include "lldb/Host/Config.h"
+
+#if LLDB_ENABLE_PYTHON
+
+#include "ScriptedPythonInterface.h"
+#include "lldb/Interpreter/Interfaces/ScriptedFrameInterface.h"
+#include <optional>
+
+namespace lldb_private {
+class ScriptedFramePythonInterface : public ScriptedFrameInterface,
+                                     public ScriptedPythonInterface {
+public:
+  ScriptedFramePythonInterface(ScriptInterpreterPythonImpl &interpreter);
+
+  llvm::Expected<StructuredData::GenericSP>
+  CreatePluginObject(llvm::StringRef class_name, ExecutionContext &exe_ctx,
+                     StructuredData::DictionarySP args_sp,
+                     StructuredData::Generic *script_obj = nullptr) override;
+
+  llvm::SmallVector<AbstractMethodRequirement>
+  GetAbstractMethodRequirements() const override {
+    return llvm::SmallVector<AbstractMethodRequirement>({{"get_id"}});
+  }
+
+  lldb::user_id_t GetID() override;
+
+  lldb::addr_t GetPC() override;
+
+  std::optional<SymbolContext> GetSymbolContext() override;
+
+  std::optional<std::string> GetFunctionName() override;
+
+  std::optional<std::string> GetDisplayFunctionName() override;
+
+  bool IsInlined() override;
+
+  bool IsArtificial() override;
+
+  bool IsHidden() override;
+
+  StructuredData::DictionarySP GetRegisterInfo() override;
+
+  std::optional<std::string> GetRegisterContext() override;
+};
+} // namespace lldb_private
+
+#endif // LLDB_ENABLE_PYTHON
+#endif // LLDB_PLUGINS_SCRIPTINTERPRETER_PYTHON_INTERFACES_SCRIPTEDFRAMEPYTHONINTERFACE_H