LLVM 17.0.0git
DWARFUnitIndex.h
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1//===- DWARFUnitIndex.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 LLVM_DEBUGINFO_DWARF_DWARFUNITINDEX_H
10#define LLVM_DEBUGINFO_DWARF_DWARFUNITINDEX_H
11
12#include "llvm/ADT/ArrayRef.h"
13#include "llvm/ADT/StringRef.h"
14#include <cstdint>
15#include <memory>
16
17namespace llvm {
18
19class raw_ostream;
20class DataExtractor;
21
22/// The enum of section identifiers to be used in internal interfaces.
23///
24/// Pre-standard implementation of package files defined a number of section
25/// identifiers with values that clash definitions in the DWARFv5 standard.
26/// See https://gcc.gnu.org/wiki/DebugFissionDWP and Section 7.3.5.3 in DWARFv5.
27///
28/// The following identifiers are the same in the proposal and in DWARFv5:
29/// - DW_SECT_INFO = 1 (.debug_info.dwo)
30/// - DW_SECT_ABBREV = 3 (.debug_abbrev.dwo)
31/// - DW_SECT_LINE = 4 (.debug_line.dwo)
32/// - DW_SECT_STR_OFFSETS = 6 (.debug_str_offsets.dwo)
33///
34/// The following identifiers are defined only in DWARFv5:
35/// - DW_SECT_LOCLISTS = 5 (.debug_loclists.dwo)
36/// - DW_SECT_RNGLISTS = 8 (.debug_rnglists.dwo)
37///
38/// The following identifiers are defined only in the GNU proposal:
39/// - DW_SECT_TYPES = 2 (.debug_types.dwo)
40/// - DW_SECT_LOC = 5 (.debug_loc.dwo)
41/// - DW_SECT_MACINFO = 7 (.debug_macinfo.dwo)
42///
43/// DW_SECT_MACRO for the .debug_macro.dwo section is defined in both standards,
44/// but with different values, 8 in GNU and 7 in DWARFv5.
45///
46/// This enum defines constants to represent the identifiers of both sets.
47/// For DWARFv5 ones, the values are the same as defined in the standard.
48/// For pre-standard ones that correspond to sections being deprecated in
49/// DWARFv5, the values are chosen arbitrary and a tag "_EXT_" is added to
50/// the names.
51///
52/// The enum is for internal use only. The user should not expect the values
53/// to correspond to any input/output constants. Special conversion functions,
54/// serializeSectionKind() and deserializeSectionKind(), should be used for
55/// the translation.
57 /// Denotes a value read from an index section that does not correspond
58 /// to any of the supported standards.
60#define HANDLE_DW_SECT(ID, NAME) DW_SECT_##NAME = ID,
61#include "llvm/BinaryFormat/Dwarf.def"
65};
66
67inline const char *toString(DWARFSectionKind Kind) {
68 switch (Kind) {
70 return "Unknown DW_SECT value 0";
71#define STRINGIZE(X) #X
72#define HANDLE_DW_SECT(ID, NAME) \
73 case DW_SECT_##NAME: \
74 return "DW_SECT_" STRINGIZE(NAME);
75#include "llvm/BinaryFormat/Dwarf.def"
77 return "DW_SECT_TYPES";
78 case DW_SECT_EXT_LOC:
79 return "DW_SECT_LOC";
81 return "DW_SECT_MACINFO";
82 }
83 llvm_unreachable("unknown DWARFSectionKind");
84}
85
86/// Convert the internal value for a section kind to an on-disk value.
87///
88/// The conversion depends on the version of the index section.
89/// IndexVersion is expected to be either 2 for pre-standard GNU proposal
90/// or 5 for DWARFv5 package file.
91uint32_t serializeSectionKind(DWARFSectionKind Kind, unsigned IndexVersion);
92
93/// Convert a value read from an index section to the internal representation.
94///
95/// The conversion depends on the index section version, which is expected
96/// to be either 2 for pre-standard GNU proposal or 5 for DWARFv5 package file.
97DWARFSectionKind deserializeSectionKind(uint32_t Value, unsigned IndexVersion);
98
100 struct Header {
101 uint32_t Version;
102 uint32_t NumColumns;
103 uint32_t NumUnits;
104 uint32_t NumBuckets = 0;
105
106 bool parse(DataExtractor IndexData, uint64_t *OffsetPtr);
107 void dump(raw_ostream &OS) const;
108 };
109
110public:
111 class Entry {
112 public:
114 private:
115 uint64_t Offset;
116 uint64_t Length;
117
118 public:
119 SectionContribution() : Offset(0), Length(0) {}
121 : Offset(Offset), Length(Length) {}
122
123 void setOffset(uint64_t Value) { Offset = Value; }
125 uint64_t getOffset() const { return Offset; }
126 uint64_t getLength() const { return Length; }
127 uint32_t getOffset32() const { return (uint32_t)Offset; }
128 uint32_t getLength32() const { return (uint32_t)Length; }
129 };
130
131 private:
132 const DWARFUnitIndex *Index;
133 uint64_t Signature;
134 std::unique_ptr<SectionContribution[]> Contributions;
135 friend class DWARFUnitIndex;
136
137 public:
141
143 return Contributions.get();
144 }
145
146 uint64_t getSignature() const { return Signature; }
147 bool isValid() { return Index; }
148 };
149
150private:
151 struct Header Header;
152
153 DWARFSectionKind InfoColumnKind;
154 int InfoColumn = -1;
155 std::unique_ptr<DWARFSectionKind[]> ColumnKinds;
156 // This is a parallel array of section identifiers as they read from the input
157 // file. The mapping from raw values to DWARFSectionKind is not revertable in
158 // case of unknown identifiers, so we keep them here.
159 std::unique_ptr<uint32_t[]> RawSectionIds;
160 std::unique_ptr<Entry[]> Rows;
161 mutable std::vector<Entry *> OffsetLookup;
162
163 static StringRef getColumnHeader(DWARFSectionKind DS);
164
165 bool parseImpl(DataExtractor IndexData);
166
167public:
169 : InfoColumnKind(InfoColumnKind) {}
170
171 explicit operator bool() const { return Header.NumBuckets; }
172
173 bool parse(DataExtractor IndexData);
174 void dump(raw_ostream &OS) const;
175
176 uint32_t getVersion() const { return Header.Version; }
177
178 const Entry *getFromOffset(uint64_t Offset) const;
179 const Entry *getFromHash(uint64_t Offset) const;
180
182 return ArrayRef(ColumnKinds.get(), Header.NumColumns);
183 }
184
186 return ArrayRef(Rows.get(), Header.NumBuckets);
187 }
188
190 return MutableArrayRef(Rows.get(), Header.NumBuckets);
191 }
192};
193
194} // end namespace llvm
195
196#endif // LLVM_DEBUGINFO_DWARF_DWARFUNITINDEX_H
uint32_t Index
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
SectionContribution(uint64_t Offset, uint64_t Length)
uint64_t getSignature() const
const SectionContribution * getContribution() const
const SectionContribution * getContributions() const
uint32_t getVersion() const
MutableArrayRef< Entry > getMutableRows()
void dump(raw_ostream &OS) const
DWARFUnitIndex(DWARFSectionKind InfoColumnKind)
const Entry * getFromHash(uint64_t Offset) const
ArrayRef< DWARFSectionKind > getColumnKinds() const
ArrayRef< Entry > getRows() const
const Entry * getFromOffset(uint64_t Offset) const
MutableArrayRef - Represent a mutable reference to an array (0 or more elements consecutively in memo...
Definition: ArrayRef.h:305
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
LLVM Value Representation.
Definition: Value.h:74
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
std::optional< const char * > toString(const std::optional< DWARFFormValue > &V)
Take an optional DWARFFormValue and try to extract a string value from it.
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
void dump(const SparseBitVector< ElementSize > &LHS, raw_ostream &out)
@ Offset
Definition: DWP.cpp:406
@ Length
Definition: DWP.cpp:406
DWARFSectionKind deserializeSectionKind(uint32_t Value, unsigned IndexVersion)
Convert a value read from an index section to the internal representation.
DWARFSectionKind
The enum of section identifiers to be used in internal interfaces.
@ DW_SECT_EXT_LOC
@ DW_SECT_EXT_unknown
Denotes a value read from an index section that does not correspond to any of the supported standards...
@ DW_SECT_EXT_TYPES
@ DW_SECT_EXT_MACINFO
uint32_t serializeSectionKind(DWARFSectionKind Kind, unsigned IndexVersion)
Convert the internal value for a section kind to an on-disk value.
Definition: regcomp.c:192