[Lldb-commits] [lldb] [LLDB] Add AST node classes, functions, etc. for Data Inspection Lang… (PR #95738)

[Pavel Labath via lldb-commits]

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@@ -0,0 +1,459 @@
+//===-- DILAST.h ------------------------------------------------*- C++ -*-===//
+//
+// 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_CORE_DILAST_H
+#define LLDB_CORE_DILAST_H
+
+#include <memory>
+#include <optional>
+#include <string>
+#include <variant>
+#include <vector>
+
+#include "lldb/Core/ValueObject.h"
+#include "lldb/Symbol/Type.h"
+#include "lldb/Symbol/TypeList.h"
+#include "lldb/Target/LanguageRuntime.h"
+#include "lldb/Utility/ConstString.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/TokenKinds.h"
+#include "llvm/ADT/APFloat.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/Support/Casting.h"
+
+namespace lldb_private {
+
+namespace DIL {
+
+/// Struct to hold information about member fields. Used by the parser for the
+/// Data Inspection Language (DIL).
+struct MemberInfo {
+  std::optional<std::string> name;
+  CompilerType type;
+  std::optional<uint32_t> bitfield_size_in_bits;
+  bool is_synthetic;
+  bool is_dynamic;
+  lldb::ValueObjectSP val_obj_sp;
+};
+
+/// Get the appropriate ValueObjectSP, consulting the use_dynamic and
+/// use_synthetic options passed, acquiring the process & target locks if
+/// appropriate.
+lldb::ValueObjectSP GetDynamicOrSyntheticValue(
+    lldb::ValueObjectSP valobj_sp,
+    lldb::DynamicValueType use_dynamic = lldb::eNoDynamicValues,
+    bool use_synthetic = false);
+
+/// The various types DIL AST nodes (used by the DIL parser).
+enum class NodeKind {
+  eErrorNode,
+  eScalarLiteralNode,
+  eStringLiteralNode,
+  eIdentifierNode,
+  eCStyleCastNode,
+  eMemberOfNode,
+  eArraySubscriptNode,
+  eUnaryOpNode,
+  eSmartPtrToPtrDecayNode
+};
+
+/// The C-Style casts for type promotion allowed by DIL.
+enum class TypePromotionCastKind {
+  eArithmetic,
+  ePointer,
+};
+
+/// The Unary operators recognized by DIL.
+enum class UnaryOpKind {
+  AddrOf, // "&"
+  Deref,  // "*"
+  Minus,  // "-"
+};
+
+/// Given a string representing a type, returns the CompilerType corresponding
+/// to the named type, if it exists.
+CompilerType
+ResolveTypeByName(const std::string &name,
+                  std::shared_ptr<ExecutionContextScope> ctx_scope);
+
+/// Class used to store & manipulate information about identifiers.
+class IdentifierInfo {
+private:
+  using MemberPath = std::vector<uint32_t>;
+  using IdentifierInfoUP = std::unique_ptr<IdentifierInfo>;
+
+public:
+  enum class Kind {
+    eValue,
+    eContextArg,
+    eMemberPath,
+    eThisKeyword,
+  };
+
+  static IdentifierInfoUP FromValue(lldb::ValueObjectSP value_sp) {
----------------
labath wrote:

Hmm... this ties in to the IsValid discussion we had on a different object (DILMemberInfo). Since all of the factory functions creating these objects return a pointer, I think that having an extra IsValid() method is unnecessary and/or confusing as the (in)validity of the result could be indicated by the (in)validity of the pointer.
That I think would also make it natural to move this check to the caller, as it could do something like:
```
if (value_sp) return IdentifierInfo::FromValue(value_sp);
return nullptr;
```

https://github.com/llvm/llvm-project/pull/95738