[clang] [clang-repl] Simplify the value printing logic to enable out-of-process. (PR #107737)

[Aaron Ballman via cfe-commits]

================
@@ -77,42 +78,46 @@ class IncrementalCompilerBuilder {
   llvm::StringRef CudaSDKPath;
 };
 
-/// Generate glue code between the Interpreter's built-in runtime and user code.
-class RuntimeInterfaceBuilder {
-public:
-  virtual ~RuntimeInterfaceBuilder() = default;
-
-  using TransformExprFunction = ExprResult(RuntimeInterfaceBuilder *Builder,
-                                           Expr *, ArrayRef<Expr *>);
-  virtual TransformExprFunction *getPrintValueTransformer() = 0;
-};
+class IncrementalAction;
+class InProcessPrintingASTConsumer;
 
 /// Provides top-level interfaces for incremental compilation and execution.
 class Interpreter {
+  friend class Value;
+  friend InProcessPrintingASTConsumer;
+
   std::unique_ptr<llvm::orc::ThreadSafeContext> TSCtx;
+  /// Long-lived, incremental parsing action.
+  std::unique_ptr<IncrementalAction> Act;
   std::unique_ptr<IncrementalParser> IncrParser;
   std::unique_ptr<IncrementalExecutor> IncrExecutor;
-  std::unique_ptr<RuntimeInterfaceBuilder> RuntimeIB;
 
   // An optional parser for CUDA offloading
   std::unique_ptr<IncrementalParser> DeviceParser;
 
+  /// List containing every information about every incrementally parsed piece
----------------
AaronBallman wrote:

```suggestion
  /// List containing information about every incrementally parsed piece
```

https://github.com/llvm/llvm-project/pull/107737