1 //===- UDTLayout.h - UDT layout info ----------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef LLVM_DEBUGINFO_PDB_UDTLAYOUT_H
11 #define LLVM_DEBUGINFO_PDB_UDTLAYOUT_H
12 
13 #include "llvm/ADT/ArrayRef.h"
14 #include "llvm/ADT/BitVector.h"
15 #include "llvm/ADT/StringRef.h"
16 #include "llvm/DebugInfo/PDB/PDBSymbol.h"
17 #include "llvm/DebugInfo/PDB/PDBSymbolData.h"
18 #include "llvm/DebugInfo/PDB/PDBSymbolTypeBaseClass.h"
19 #include "llvm/DebugInfo/PDB/PDBSymbolTypeBuiltin.h"
20 #include "llvm/DebugInfo/PDB/PDBSymbolTypeUDT.h"
21 #include "llvm/DebugInfo/PDB/PDBSymbolTypeVTable.h"
22 #include "llvm/DebugInfo/PDB/PDBTypes.h"
23 #include <cstdint>
24 #include <memory>
25 #include <string>
26 #include <vector>
27 
28 namespace llvm {
29 namespace pdb {
30 
31 class BaseClassLayout;
32 class ClassLayout;
33 class UDTLayoutBase;
34 
35 class LayoutItemBase {
36 public:
37   LayoutItemBase(const UDTLayoutBase *Parent, const PDBSymbol *Symbol,
38                  const std::string &Name, uint32_t OffsetInParent,
39                  uint32_t Size, bool IsElided);
40   virtual ~LayoutItemBase() = default;
41 
42   uint32_t deepPaddingSize() const;
immediatePadding()43   virtual uint32_t immediatePadding() const { return 0; }
44   virtual uint32_t tailPadding() const;
45 
getParent()46   const UDTLayoutBase *getParent() const { return Parent; }
getName()47   StringRef getName() const { return Name; }
getOffsetInParent()48   uint32_t getOffsetInParent() const { return OffsetInParent; }
getSize()49   uint32_t getSize() const { return SizeOf; }
getLayoutSize()50   uint32_t getLayoutSize() const { return LayoutSize; }
getSymbol()51   const PDBSymbol *getSymbol() const { return Symbol; }
usedBytes()52   const BitVector &usedBytes() const { return UsedBytes; }
isElided()53   bool isElided() const { return IsElided; }
isVBPtr()54   virtual bool isVBPtr() const { return false; }
55 
containsOffset(uint32_t Off)56   uint32_t containsOffset(uint32_t Off) const {
57     uint32_t Begin = getOffsetInParent();
58     uint32_t End = Begin + getSize();
59     return (Off >= Begin && Off < End);
60   }
61 
62 protected:
63   const PDBSymbol *Symbol = nullptr;
64   const UDTLayoutBase *Parent = nullptr;
65   BitVector UsedBytes;
66   std::string Name;
67   uint32_t OffsetInParent = 0;
68   uint32_t SizeOf = 0;
69   uint32_t LayoutSize = 0;
70   bool IsElided = false;
71 };
72 
73 class VBPtrLayoutItem : public LayoutItemBase {
74 public:
75   VBPtrLayoutItem(const UDTLayoutBase &Parent,
76                   std::unique_ptr<PDBSymbolTypeBuiltin> Sym, uint32_t Offset,
77                   uint32_t Size);
78 
isVBPtr()79   bool isVBPtr() const override { return true; }
80 
81 private:
82   std::unique_ptr<PDBSymbolTypeBuiltin> Type;
83 };
84 
85 class DataMemberLayoutItem : public LayoutItemBase {
86 public:
87   DataMemberLayoutItem(const UDTLayoutBase &Parent,
88                        std::unique_ptr<PDBSymbolData> DataMember);
89 
90   const PDBSymbolData &getDataMember();
91   bool hasUDTLayout() const;
92   const ClassLayout &getUDTLayout() const;
93 
94 private:
95   std::unique_ptr<PDBSymbolData> DataMember;
96   std::unique_ptr<ClassLayout> UdtLayout;
97 };
98 
99 class VTableLayoutItem : public LayoutItemBase {
100 public:
101   VTableLayoutItem(const UDTLayoutBase &Parent,
102                    std::unique_ptr<PDBSymbolTypeVTable> VTable);
103 
getElementSize()104   uint32_t getElementSize() const { return ElementSize; }
105 
106 private:
107   uint32_t ElementSize = 0;
108   std::unique_ptr<PDBSymbolTypeVTable> VTable;
109 };
110 
111 class UDTLayoutBase : public LayoutItemBase {
112   template <typename T> using UniquePtrVector = std::vector<std::unique_ptr<T>>;
113 
114 public:
115   UDTLayoutBase(const UDTLayoutBase *Parent, const PDBSymbol &Sym,
116                 const std::string &Name, uint32_t OffsetInParent, uint32_t Size,
117                 bool IsElided);
118 
119   uint32_t tailPadding() const override;
layout_items()120   ArrayRef<LayoutItemBase *> layout_items() const { return LayoutItems; }
bases()121   ArrayRef<BaseClassLayout *> bases() const { return AllBases; }
regular_bases()122   ArrayRef<BaseClassLayout *> regular_bases() const { return NonVirtualBases; }
virtual_bases()123   ArrayRef<BaseClassLayout *> virtual_bases() const { return VirtualBases; }
directVirtualBaseCount()124   uint32_t directVirtualBaseCount() const { return DirectVBaseCount; }
funcs()125   ArrayRef<std::unique_ptr<PDBSymbolFunc>> funcs() const { return Funcs; }
other_items()126   ArrayRef<std::unique_ptr<PDBSymbol>> other_items() const { return Other; }
127 
128 protected:
129   bool hasVBPtrAtOffset(uint32_t Off) const;
130   void initializeChildren(const PDBSymbol &Sym);
131 
132   void addChildToLayout(std::unique_ptr<LayoutItemBase> Child);
133 
134   uint32_t DirectVBaseCount = 0;
135 
136   UniquePtrVector<PDBSymbol> Other;
137   UniquePtrVector<PDBSymbolFunc> Funcs;
138   UniquePtrVector<LayoutItemBase> ChildStorage;
139   std::vector<LayoutItemBase *> LayoutItems;
140 
141   std::vector<BaseClassLayout *> AllBases;
142   ArrayRef<BaseClassLayout *> NonVirtualBases;
143   ArrayRef<BaseClassLayout *> VirtualBases;
144 
145   VTableLayoutItem *VTable = nullptr;
146   VBPtrLayoutItem *VBPtr = nullptr;
147 };
148 
149 class BaseClassLayout : public UDTLayoutBase {
150 public:
151   BaseClassLayout(const UDTLayoutBase &Parent, uint32_t OffsetInParent,
152                   bool Elide, std::unique_ptr<PDBSymbolTypeBaseClass> Base);
153 
getBase()154   const PDBSymbolTypeBaseClass &getBase() const { return *Base; }
isVirtualBase()155   bool isVirtualBase() const { return IsVirtualBase; }
isEmptyBase()156   bool isEmptyBase() { return SizeOf == 1 && LayoutSize == 0; }
157 
158 private:
159   std::unique_ptr<PDBSymbolTypeBaseClass> Base;
160   bool IsVirtualBase;
161 };
162 
163 class ClassLayout : public UDTLayoutBase {
164 public:
165   explicit ClassLayout(const PDBSymbolTypeUDT &UDT);
166   explicit ClassLayout(std::unique_ptr<PDBSymbolTypeUDT> UDT);
167 
168   ClassLayout(ClassLayout &&Other) = default;
169 
getClass()170   const PDBSymbolTypeUDT &getClass() const { return UDT; }
171   uint32_t immediatePadding() const override;
172 
173 private:
174   BitVector ImmediateUsedBytes;
175   std::unique_ptr<PDBSymbolTypeUDT> OwnedStorage;
176   const PDBSymbolTypeUDT &UDT;
177 };
178 
179 } // end namespace pdb
180 } // end namespace llvm
181 
182 #endif // LLVM_DEBUGINFO_PDB_UDTLAYOUT_H
183