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

[via lldb-commits]

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@@ -0,0 +1,446 @@
+//===-- 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_DIL_AST_H_
+#define LLDB_DIL_AST_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"
+
+namespace lldb_private {
+
+/// Struct to hold information about member fields. Used by the parser for the
+/// Data Inspection Language (DIL).
+struct DILMemberInfo {
+  std::optional<std::string> name;
+  CompilerType type;
+  bool is_bitfield;
+  uint32_t bitfield_size_in_bits;
+  bool is_synthetic;
+  bool is_dynamic;
+  lldb::ValueObjectSP val_obj_sp;
+
+  explicit operator bool() const { return type.IsValid(); }
+};
+
+/// This determines if the type is a shared, unique or weak pointer, either
+/// from stdlibc++ or libc+++.
+bool IsSmartPtrType(CompilerType type);
+
+/// Finds the member field with the given name and type, stores the child index
+/// corresponding to the field in the idx vector and returns a DILMemberInfo
+/// struct with appropriate information about the field.
+DILMemberInfo GetFieldWithNameIndexPath(lldb::ValueObjectSP lhs_val_sp,
+                                        CompilerType type,
+                                        const std::string &name,
+                                        std::vector<uint32_t> *idx,
+                                        CompilerType empty_type,
+                                        bool use_synthetic, bool is_dynamic);
+
+std::tuple<DILMemberInfo, std::vector<uint32_t>>
+GetMemberInfo(lldb::ValueObjectSP lhs_val_sp, CompilerType type,
+              const std::string &name, bool use_synthetic);
+
+/// Get the appropriate ValueObjectSP, consulting the use_dynamic and
+/// use_synthetic options passed, acquiring the process & target locks if
+/// appropriate.
+lldb::ValueObjectSP
+DILGetSPWithLock(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 DILNodeKind {
+  kDILErrorNode,
+  kLiteralNode,
+  kIdentifierNode,
+  kBuiltinFunctionCallNode,
+  kCStyleCastNode,
+  kMemberOfNode,
+  kArraySubscriptNode,
+  kUnaryOpNode,
+  kSmartPtrToPtrDecay
+};
+
+/// The C-Style casts allowed by DIL.
+enum class CStyleCastKind {
+  kArithmetic,
+  kEnumeration,
+  kPointer,
+  kNullptr,
+  kReference,
+};
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cmtice wrote:

Frame var doesn't allow users to specify casts of variables, but it does do some implicit type conversions/casting when evaluating variables, e.g. arrays-to-pointers, and various implicit type promotions & conversions. The DIL stripped down parser/evaluator still needs to do these promotions & conversions, and uses these for that work.

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