[LLDB] Add framework for Data Inspection Language (DIL) work. (#115666)

Add the framework code for hooking up and calling the Data Inspection
Language (DIL) implementation, as an alternate implementation for the
'frame variable' command. For now, this is an opt-in option, via a
target setting 'target.experimental.use-DIL'. See
https://discourse.llvm.org/t/rfc-data-inspection-language/69893 for more
information about this project.

This PR does not actually call any of the DIL code; instead the piece
that will eventually call the DIL code
(StackFrame::DILEvaluateVariableExpression) calls back into the original
'frame variable' implementation.

1 files changed, 21 insertions, 0 deletions

diff --git a/lldb/source/Target/Target.cpp b/lldb/source/Target/Target.cpp
index a788bad88b29..300dca163c41 100644
--- a/lldb/source/Target/Target.cpp
+++ b/lldb/source/Target/Target.cpp
@@ -4385,6 +4385,27 @@ bool TargetProperties::GetInjectLocalVariables(
       .value_or(true);
 }
 
+bool TargetProperties::GetUseDIL(ExecutionContext *exe_ctx) const {
+  const Property *exp_property =
+      m_collection_sp->GetPropertyAtIndex(ePropertyExperimental, exe_ctx);
+  OptionValueProperties *exp_values =
+      exp_property->GetValue()->GetAsProperties();
+  if (exp_values)
+    return exp_values->GetPropertyAtIndexAs<bool>(ePropertyUseDIL, exe_ctx)
+        .value_or(false);
+  else
+    return true;
+}
+
+void TargetProperties::SetUseDIL(ExecutionContext *exe_ctx, bool b) {
+  const Property *exp_property =
+      m_collection_sp->GetPropertyAtIndex(ePropertyExperimental, exe_ctx);
+  OptionValueProperties *exp_values =
+      exp_property->GetValue()->GetAsProperties();
+  if (exp_values)
+    exp_values->SetPropertyAtIndex(ePropertyUseDIL, true, exe_ctx);
+}
+
 ArchSpec TargetProperties::GetDefaultArchitecture() const {
   const uint32_t idx = ePropertyDefaultArch;
   return GetPropertyAtIndexAs<ArchSpec>(idx, {});