//===- DWARFUnitIndex.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 LLVM_DEBUGINFO_DWARF_DWARFUNITINDEX_H
#define LLVM_DEBUGINFO_DWARF_DWARFUNITINDEX_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/StringRef.h"
#include <cstdint>
#include <memory>
namespace llvm {
class raw_ostream;
class DataExtractor;
/// The enum of section identifiers to be used in internal interfaces.
///
/// Pre-standard implementation of package files defined a number of section
/// identifiers with values that clash definitions in the DWARFv5 standard.
/// See https://gcc.gnu.org/wiki/DebugFissionDWP and Section 7.3.5.3 in DWARFv5.
///
/// The following identifiers are the same in the proposal and in DWARFv5:
/// - DW_SECT_INFO = 1 (.debug_info.dwo)
/// - DW_SECT_ABBREV = 3 (.debug_abbrev.dwo)
/// - DW_SECT_LINE = 4 (.debug_line.dwo)
/// - DW_SECT_STR_OFFSETS = 6 (.debug_str_offsets.dwo)
///
/// The following identifiers are defined only in DWARFv5:
/// - DW_SECT_LOCLISTS = 5 (.debug_loclists.dwo)
/// - DW_SECT_RNGLISTS = 8 (.debug_rnglists.dwo)
///
/// The following identifiers are defined only in the GNU proposal:
/// - DW_SECT_TYPES = 2 (.debug_types.dwo)
/// - DW_SECT_LOC = 5 (.debug_loc.dwo)
/// - DW_SECT_MACINFO = 7 (.debug_macinfo.dwo)
///
/// DW_SECT_MACRO for the .debug_macro.dwo section is defined in both standards,
/// but with different values, 8 in GNU and 7 in DWARFv5.
///
/// This enum defines constants to represent the identifiers of both sets.
/// For DWARFv5 ones, the values are the same as defined in the standard.
/// For pre-standard ones that correspond to sections being deprecated in
/// DWARFv5, the values are chosen arbitrary and a tag "_EXT_" is added to
/// the names.
///
/// The enum is for internal use only. The user should not expect the values
/// to correspond to any input/output constants. Special conversion functions,
/// serializeSectionKind() and deserializeSectionKind(), should be used for
/// the translation.
enum DWARFSectionKind {
/// Denotes a value read from an index section that does not correspond
/// to any of the supported standards.
DW_SECT_EXT_unknown = 0,
#define HANDLE_DW_SECT(ID, NAME) DW_SECT_##NAME = ID,
#include "llvm/BinaryFormat/Dwarf.def"
DW_SECT_EXT_TYPES = 2,
DW_SECT_EXT_LOC = 9,
DW_SECT_EXT_MACINFO = 10,
};
inline const char *toString(DWARFSectionKind Kind) {
switch (Kind) {
case DW_SECT_EXT_unknown:
return "Unknown DW_SECT value 0";
#define STRINGIZE(X) #X
#define HANDLE_DW_SECT(ID, NAME) \
case DW_SECT_##NAME: \
return "DW_SECT_" STRINGIZE(NAME);
#include "llvm/BinaryFormat/Dwarf.def"
case DW_SECT_EXT_TYPES:
return "DW_SECT_TYPES";
case DW_SECT_EXT_LOC:
return "DW_SECT_LOC";
case DW_SECT_EXT_MACINFO:
return "DW_SECT_MACINFO";
}
llvm_unreachable("unknown DWARFSectionKind");
}
/// Convert the internal value for a section kind to an on-disk value.
///
/// The conversion depends on the version of the index section.
/// IndexVersion is expected to be either 2 for pre-standard GNU proposal
/// or 5 for DWARFv5 package file.
uint32_t serializeSectionKind(DWARFSectionKind Kind, unsigned IndexVersion);
/// Convert a value read from an index section to the internal representation.
///
/// The conversion depends on the index section version, which is expected
/// to be either 2 for pre-standard GNU proposal or 5 for DWARFv5 package file.
DWARFSectionKind deserializeSectionKind(uint32_t Value, unsigned IndexVersion);
class DWARFUnitIndex {
struct Header {
uint32_t Version;
uint32_t NumColumns;
uint32_t NumUnits;
uint32_t NumBuckets = 0;
bool parse(DataExtractor IndexData, uint64_t *OffsetPtr);
void dump(raw_ostream &OS) const;
};
public:
class Entry {
public:
class SectionContribution {
private:
uint64_t Offset;
uint64_t Length;
public:
SectionContribution() : Offset(0), Length(0) {}
SectionContribution(uint64_t Offset, uint64_t Length)
: Offset(Offset), Length(Length) {}
void setOffset(uint64_t Value) { Offset = Value; }
void setLength(uint64_t Value) { Length = Value; }
uint64_t getOffset() const { return Offset; }
uint64_t getLength() const { return Length; }
uint32_t getOffset32() const { return (uint32_t)Offset; }
uint32_t getLength32() const { return (uint32_t)Length; }
};
private:
const DWARFUnitIndex *Index;
uint64_t Signature;
std::unique_ptr<SectionContribution[]> Contributions;
friend class DWARFUnitIndex;
public:
const SectionContribution *getContribution(DWARFSectionKind Sec) const;
const SectionContribution *getContribution() const;
SectionContribution &getContribution();
const SectionContribution *getContributions() const {
return Contributions.get();
}
uint64_t getSignature() const { return Signature; }
bool isValid() { return Index; }
};
private:
struct Header Header;
DWARFSectionKind InfoColumnKind;
int InfoColumn = -1;
std::unique_ptr<DWARFSectionKind[]> ColumnKinds;
// This is a parallel array of section identifiers as they read from the input
// file. The mapping from raw values to DWARFSectionKind is not revertable in
// case of unknown identifiers, so we keep them here.
std::unique_ptr<uint32_t[]> RawSectionIds;
std::unique_ptr<Entry[]> Rows;
mutable std::vector<Entry *> OffsetLookup;
static StringRef getColumnHeader(DWARFSectionKind DS);
bool parseImpl(DataExtractor IndexData);
public:
DWARFUnitIndex(DWARFSectionKind InfoColumnKind)
: InfoColumnKind(InfoColumnKind) {}
explicit operator bool() const { return Header.NumBuckets; }
bool parse(DataExtractor IndexData);
void dump(raw_ostream &OS) const;
uint32_t getVersion() const { return Header.Version; }
const Entry *getFromOffset(uint64_t Offset) const;
const Entry *getFromHash(uint64_t Offset) const;
ArrayRef<DWARFSectionKind> getColumnKinds() const {
return ArrayRef(ColumnKinds.get(), Header.NumColumns);
}
ArrayRef<Entry> getRows() const {
return ArrayRef(Rows.get(), Header.NumBuckets);
}
MutableArrayRef<Entry> getMutableRows() {
return MutableArrayRef(Rows.get(), Header.NumBuckets);
}
};
} // end namespace llvm
#endif // LLVM_DEBUGINFO_DWARF_DWARFUNITINDEX_H