1 //===-- DWARFDebugInfoEntry.h -----------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFDEBUGINFOENTRY_H
10 #define LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFDEBUGINFOENTRY_H
11 
12 #include "SymbolFileDWARF.h"
13 #include "llvm/ADT/SmallVector.h"
14 
15 #include "DWARFAbbreviationDeclaration.h"
16 #include "DWARFBaseDIE.h"
17 #include "DWARFDebugAbbrev.h"
18 #include "DWARFDebugRanges.h"
19 #include <map>
20 #include <optional>
21 #include <set>
22 #include <vector>
23 
24 class DWARFDeclContext;
25 
26 #define DIE_SIBLING_IDX_BITSIZE 31
27 
28 /// DWARFDebugInfoEntry objects assume that they are living in one big
29 /// vector and do pointer arithmetic on their this pointers. Don't
30 /// pass them by value. Due to the way they are constructed in a
31 /// std::vector, we cannot delete the copy constructor.
32 class DWARFDebugInfoEntry {
33 public:
34   typedef std::vector<DWARFDebugInfoEntry> collection;
35   typedef collection::iterator iterator;
36   typedef collection::const_iterator const_iterator;
37 
38   DWARFDebugInfoEntry()
39       : m_offset(DW_INVALID_OFFSET), m_sibling_idx(0), m_has_children(false) {}
40 
41   explicit operator bool() const { return m_offset != DW_INVALID_OFFSET; }
42   bool operator==(const DWARFDebugInfoEntry &rhs) const;
43   bool operator!=(const DWARFDebugInfoEntry &rhs) const;
44 
45   void BuildFunctionAddressRangeTable(DWARFUnit *cu,
46                                       DWARFDebugAranges *debug_aranges) const;
47 
48   bool Extract(const lldb_private::DWARFDataExtractor &data,
49                const DWARFUnit *cu, lldb::offset_t *offset_ptr);
50 
51   using Recurse = DWARFBaseDIE::Recurse;
52   size_t GetAttributes(DWARFUnit *cu, DWARFAttributes &attrs,
53                        Recurse recurse = Recurse::yes) const {
54     return GetAttributes(cu, attrs, recurse, 0 /* curr_depth */);
55   }
56 
57   dw_offset_t
58   GetAttributeValue(const DWARFUnit *cu, const dw_attr_t attr,
59                     DWARFFormValue &formValue,
60                     dw_offset_t *end_attr_offset_ptr = nullptr,
61                     bool check_specification_or_abstract_origin = false) const;
62 
63   const char *GetAttributeValueAsString(
64       const DWARFUnit *cu, const dw_attr_t attr, const char *fail_value,
65       bool check_specification_or_abstract_origin = false) const;
66 
67   uint64_t GetAttributeValueAsUnsigned(
68       const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value,
69       bool check_specification_or_abstract_origin = false) const;
70 
71   std::optional<uint64_t> GetAttributeValueAsOptionalUnsigned(
72       const DWARFUnit *cu, const dw_attr_t attr,
73       bool check_specification_or_abstract_origin = false) const;
74 
75   DWARFDIE GetAttributeValueAsReference(
76       const DWARFUnit *cu, const dw_attr_t attr,
77       bool check_specification_or_abstract_origin = false) const;
78 
79   uint64_t GetAttributeValueAsAddress(
80       const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value,
81       bool check_specification_or_abstract_origin = false) const;
82 
83   dw_addr_t
84   GetAttributeHighPC(const DWARFUnit *cu, dw_addr_t lo_pc, uint64_t fail_value,
85                      bool check_specification_or_abstract_origin = false) const;
86 
87   bool GetAttributeAddressRange(
88       const DWARFUnit *cu, dw_addr_t &lo_pc, dw_addr_t &hi_pc,
89       uint64_t fail_value,
90       bool check_specification_or_abstract_origin = false) const;
91 
92   size_t GetAttributeAddressRanges(
93       DWARFUnit *cu, DWARFRangeList &ranges, bool check_hi_lo_pc,
94       bool check_specification_or_abstract_origin = false) const;
95 
96   const char *GetName(const DWARFUnit *cu) const;
97 
98   const char *GetMangledName(const DWARFUnit *cu,
99                              bool substitute_name_allowed = true) const;
100 
101   const char *GetPubname(const DWARFUnit *cu) const;
102 
103   bool GetDIENamesAndRanges(
104       DWARFUnit *cu, const char *&name, const char *&mangled,
105       DWARFRangeList &rangeList, int &decl_file, int &decl_line,
106       int &decl_column, int &call_file, int &call_line, int &call_column,
107       lldb_private::DWARFExpressionList *frame_base = nullptr) const;
108 
109   const DWARFAbbreviationDeclaration *
110   GetAbbreviationDeclarationPtr(const DWARFUnit *cu) const;
111 
112   lldb::offset_t GetFirstAttributeOffset() const;
113 
114   dw_tag_t Tag() const { return m_tag; }
115 
116   bool IsNULL() const { return m_abbr_idx == 0; }
117 
118   dw_offset_t GetOffset() const { return m_offset; }
119 
120   bool HasChildren() const { return m_has_children; }
121 
122   void SetHasChildren(bool b) { m_has_children = b; }
123 
124   // We know we are kept in a vector of contiguous entries, so we know
125   // our parent will be some index behind "this".
126   DWARFDebugInfoEntry *GetParent() {
127     return m_parent_idx > 0 ? this - m_parent_idx : nullptr;
128   }
129   const DWARFDebugInfoEntry *GetParent() const {
130     return m_parent_idx > 0 ? this - m_parent_idx : nullptr;
131   }
132   // We know we are kept in a vector of contiguous entries, so we know
133   // our sibling will be some index after "this".
134   DWARFDebugInfoEntry *GetSibling() {
135     return m_sibling_idx > 0 ? this + m_sibling_idx : nullptr;
136   }
137   const DWARFDebugInfoEntry *GetSibling() const {
138     return m_sibling_idx > 0 ? this + m_sibling_idx : nullptr;
139   }
140   // We know we are kept in a vector of contiguous entries, so we know
141   // we don't need to store our child pointer, if we have a child it will
142   // be the next entry in the list...
143   DWARFDebugInfoEntry *GetFirstChild() {
144     return HasChildren() ? this + 1 : nullptr;
145   }
146   const DWARFDebugInfoEntry *GetFirstChild() const {
147     return HasChildren() ? this + 1 : nullptr;
148   }
149 
150   DWARFDeclContext GetDWARFDeclContext(DWARFUnit *cu) const;
151 
152   DWARFDIE GetParentDeclContextDIE(DWARFUnit *cu) const;
153   DWARFDIE GetParentDeclContextDIE(DWARFUnit *cu,
154                                    const DWARFAttributes &attributes) const;
155 
156   void SetSiblingIndex(uint32_t idx) { m_sibling_idx = idx; }
157   void SetParentIndex(uint32_t idx) { m_parent_idx = idx; }
158 
159   // This function returns true if the variable scope is either
160   // global or (file-static). It will return false for static variables
161   // that are local to a function, as they have local scope.
162   bool IsGlobalOrStaticScopeVariable() const;
163 
164 protected:
165   static DWARFDeclContext
166   GetDWARFDeclContextStatic(const DWARFDebugInfoEntry *die, DWARFUnit *cu);
167 
168   dw_offset_t m_offset; // Offset within the .debug_info/.debug_types
169   uint32_t m_parent_idx = 0;   // How many to subtract from "this" to get the
170                                // parent. If zero this die has no parent
171   uint32_t m_sibling_idx : 31, // How many to add to "this" to get the sibling.
172       // If it is zero, then the DIE doesn't have children, or the
173       // DWARF claimed it had children but the DIE only contained
174       // a single NULL terminating child.
175       m_has_children : 1;
176   uint16_t m_abbr_idx = 0;
177   /// A copy of the DW_TAG value so we don't have to go through the compile
178   /// unit abbrev table
179   dw_tag_t m_tag = llvm::dwarf::DW_TAG_null;
180 
181 private:
182   size_t GetAttributes(DWARFUnit *cu, DWARFAttributes &attrs, Recurse recurse,
183                        uint32_t curr_depth) const;
184 };
185 
186 #endif // LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFDEBUGINFOENTRY_H
187