Skip to content

Commit

Permalink
[dwarf2yaml] Correctly emit type and split unit headers (llvm#102471)
Browse files Browse the repository at this point in the history 
(DWARFv5) split units have an extra `dwo_id` field in the header. Type
units have `type_signature` and `type_offset`.
  • Loading branch information
@labath @bwendling
labath authored and bwendling committed Aug 15, 2024
1 parent 00ac005 commit af14da5
Show file tree
Hide file tree
Showing 5 changed files with 128 additions and 28 deletions.
5 changes: 4 additions & 1 deletion llvm/include/llvm/ObjectYAML/DWARFYAML.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -115,6 +115,9 @@ struct Unit {
llvm::dwarf::UnitType Type; // Added in DWARF 5
std::optional<uint64_t> AbbrevTableID;
std::optional<yaml::Hex64> AbbrOffset;
yaml::Hex64 TypeSignatureOrDwoID; // For type or split units
yaml::Hex64 TypeOffset; // For type units

std::vector<Entry> Entries;
};

Expand Down Expand Up @@ -245,7 +248,7 @@ struct Data {
std::optional<PubSection> GNUPubNames;
std::optional<PubSection> GNUPubTypes;

std::vector<Unit> CompileUnits;
std::vector<Unit> Units;

std::vector<LineTable> DebugLines;
std::optional<std::vector<ListTable<RnglistEntry>>> DebugRnglists;
Expand Down
37 changes: 34 additions & 3 deletions llvm/lib/ObjectYAML/DWARFEmitter.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -405,17 +405,33 @@ static Expected<uint64_t> writeDIE(const DWARFYAML::Data &DI, uint64_t CUIndex,
}

Error DWARFYAML::emitDebugInfo(raw_ostream &OS, const DWARFYAML::Data &DI) {
for (uint64_t I = 0; I < DI.CompileUnits.size(); ++I) {
const DWARFYAML::Unit &Unit = DI.CompileUnits[I];
for (uint64_t I = 0; I < DI.Units.size(); ++I) {
const DWARFYAML::Unit &Unit = DI.Units[I];
uint8_t AddrSize;
if (Unit.AddrSize)
AddrSize = *Unit.AddrSize;
else
AddrSize = DI.Is64BitAddrSize ? 8 : 4;
dwarf::FormParams Params = {Unit.Version, AddrSize, Unit.Format};
uint64_t Length = 3; // sizeof(version) + sizeof(address_size)
Length += Unit.Version >= 5 ? 1 : 0; // sizeof(unit_type)
Length += Params.getDwarfOffsetByteSize(); // sizeof(debug_abbrev_offset)
if (Unit.Version >= 5) {
++Length; // sizeof(unit_type)
switch (Unit.Type) {
case dwarf::DW_UT_compile:
case dwarf::DW_UT_partial:
default:
break;
case dwarf::DW_UT_type:
case dwarf::DW_UT_split_type:
// sizeof(type_signature) + sizeof(type_offset)
Length += 8 + Params.getDwarfOffsetByteSize();
break;
case dwarf::DW_UT_skeleton:
case dwarf::DW_UT_split_compile:
Length += 8; // sizeof(dwo_id)
}
}

// Since the length of the current compilation unit is undetermined yet, we
// firstly write the content of the compilation unit to a buffer to
Expand Down Expand Up @@ -461,6 +477,21 @@ Error DWARFYAML::emitDebugInfo(raw_ostream &OS, const DWARFYAML::Data &DI) {
writeInteger((uint8_t)Unit.Type, OS, DI.IsLittleEndian);
writeInteger((uint8_t)AddrSize, OS, DI.IsLittleEndian);
writeDWARFOffset(AbbrevTableOffset, Unit.Format, OS, DI.IsLittleEndian);
switch (Unit.Type) {
case dwarf::DW_UT_compile:
case dwarf::DW_UT_partial:
default:
break;
case dwarf::DW_UT_type:
case dwarf::DW_UT_split_type:
writeInteger(Unit.TypeSignatureOrDwoID, OS, DI.IsLittleEndian);
writeDWARFOffset(Unit.TypeOffset, Unit.Format, OS, DI.IsLittleEndian);
break;
case dwarf::DW_UT_skeleton:
case dwarf::DW_UT_split_compile:
writeInteger(Unit.TypeSignatureOrDwoID, OS, DI.IsLittleEndian);
break;
}
} else {
writeDWARFOffset(AbbrevTableOffset, Unit.Format, OS, DI.IsLittleEndian);
writeInteger((uint8_t)AddrSize, OS, DI.IsLittleEndian);
Expand Down
20 changes: 18 additions & 2 deletions llvm/lib/ObjectYAML/DWARFYAML.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@ SetVector<StringRef> DWARFYAML::Data::getNonEmptySectionNames() const {
SecNames.insert("debug_addr");
if (!DebugAbbrev.empty())
SecNames.insert("debug_abbrev");
if (!CompileUnits.empty())
if (!Units.empty())
SecNames.insert("debug_info");
if (PubNames)
SecNames.insert("debug_pubnames");
Expand Down Expand Up @@ -101,7 +101,7 @@ void MappingTraits<DWARFYAML::Data>::mapping(IO &IO, DWARFYAML::Data &DWARF) {
DWARFCtx.IsGNUPubSec = true;
IO.mapOptional("debug_gnu_pubnames", DWARF.GNUPubNames);
IO.mapOptional("debug_gnu_pubtypes", DWARF.GNUPubTypes);
IO.mapOptional("debug_info", DWARF.CompileUnits);
IO.mapOptional("debug_info", DWARF.Units);
IO.mapOptional("debug_line", DWARF.DebugLines);
IO.mapOptional("debug_addr", DWARF.DebugAddr);
IO.mapOptional("debug_str_offsets", DWARF.DebugStrOffsets);
Expand Down Expand Up @@ -216,6 +216,22 @@ void MappingTraits<DWARFYAML::Unit>::mapping(IO &IO, DWARFYAML::Unit &Unit) {
IO.mapOptional("AbbrevTableID", Unit.AbbrevTableID);
IO.mapOptional("AbbrOffset", Unit.AbbrOffset);
IO.mapOptional("AddrSize", Unit.AddrSize);
if (Unit.Version >= 5) {
switch (Unit.Type) {
case dwarf::DW_UT_compile:
case dwarf::DW_UT_partial:
default:
break;
case dwarf::DW_UT_type:
case dwarf::DW_UT_split_type:
IO.mapRequired("TypeSignature", Unit.TypeSignatureOrDwoID);
IO.mapRequired("TypeOffset", Unit.TypeOffset);
break;
case dwarf::DW_UT_skeleton:
case dwarf::DW_UT_split_compile:
IO.mapRequired("DwoID", Unit.TypeSignatureOrDwoID);
}
}
IO.mapOptional("Entries", Unit.Entries);
}

Expand Down
92 changes: 71 additions & 21 deletions llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@
# SHDR-NEXT: AddressAlignment: [[ADDRALIGN]]
# SHDR-NEXT: EntrySize: 0
# DWARF32-LE-CONTENT-NEXT: SectionData (
# DWARF32-LE-CONTENT-NEXT: 0000: 34120000 05000204 34120000 01785634
# DWARF32-LE-CONTENT-NEXT: 0000: 34120000 05000304 34120000 01785634
## ^------- unit_length (4-byte)
## ^--- version (2-byte)
## ^- unit_type (1-byte) DW_UT_type
Expand Down Expand Up @@ -208,7 +208,7 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_partial
AbbrOffset: 0x1234
AddrSize: 4
Entries:
Expand Down Expand Up @@ -297,7 +297,7 @@ DWARF:
# RUN: FileCheck -DINDEX=2 -DNAME=15 -DOFFSET=0x9B -DSIZE=179 -DADDRALIGN=1 %s --check-prefixes=SHDR,DWARF32-BE-CONTENT

# DWARF32-BE-CONTENT-NEXT: SectionData (
# DWARF32-BE-CONTENT-NEXT: 0000: 00001234 00050204 00001234 01123456
# DWARF32-BE-CONTENT-NEXT: 0000: 00001234 00050304 00001234 01123456
## ^------- unit_length (4-byte)
## ^--- version (2-byte)
## ^- unit_type (1-byte) DW_UT_type
Expand Down Expand Up @@ -449,7 +449,7 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries: []

Expand All @@ -476,7 +476,7 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries: []

Expand Down Expand Up @@ -541,7 +541,7 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries:
- AbbrCode: 0
Expand All @@ -554,7 +554,7 @@ DWARF:
# RUN: FileCheck %s --check-prefix=EMPTY-ENTRIES --match-full-lines

# EMPTY-ENTRIES: Hex dump of section '.debug_info':
# EMPTY-ENTRIES-NEXT: 0x00000000 34120000 05000204 34120000 4.......4...
# EMPTY-ENTRIES-NEXT: 0x00000000 34120000 05000104 34120000 4.......4...
# EMPTY-ENTRIES-EMPTY:
## ^- 'Entries' is empty

Expand All @@ -567,7 +567,7 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries: []

Expand All @@ -579,7 +579,7 @@ DWARF:
# RUN: FileCheck %s --check-prefix=FORM --match-full-lines

# FORM: Hex dump of section '.debug_info':
# FORM-NEXT: 0x00000000 34120000 05000204 34120000 02341221 4.......4....4.!
# FORM-NEXT: 0x00000000 34120000 05000104 34120000 02341221 4.......4....4.!
## ^------- unit_length (4-byte)
## ^- abbreviation code (ULEB128)
## ^--- Form: DW_FORM_data2 (2-byte)
Expand Down Expand Up @@ -617,7 +617,7 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries:
## Test that yaml2obj emits values when the abbrev code is specified.
Expand Down Expand Up @@ -655,29 +655,58 @@ DWARF:
debug_info:
- Length: 0x1234
Version: 5
UnitType: DW_UT_type
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries:
- AbbrCode: 1
Values:
- Value: 0x1234

## j) Test that yaml2obj emits the correct DWARF64 unit headers.

## DWARFv5 unit header.
## j) Test that yaml2obj emits the correct DWARFv5 unit headers.

# RUN: yaml2obj --docnum=11 %s -o %t11.o
# RUN: llvm-readelf --hex-dump=.debug_info %t11.o | \
# RUN: FileCheck %s --check-prefix=DWARFV5-HEADER

# DWARFV5-HEADER: Hex dump of section '.debug_info':
# DWARFV5-HEADER-NEXT: 0x00000000 ffffffff 0c000000 00000000 05000208 ................
# DWARFV5-HEADER-NEXT: 0x00000000 ffffffff 0d000000 00000000 05000108 ................
## ^------------------------- unit_length (12-byte)
## ^--- version (2-byte)
## ^- unit_type (1-byte)
## ^- address_size (1-byte)
# DWARFV5-HEADER-NEXT: 0x00000010 34120000 00000000 4.......
# DWARFV5-HEADER-NEXT: 0x00000010 34120000 00000000 00150000 00050002 4...............
## ^---------------- debug_abbrev_offset (8-byte)
## ^- End of children (1-byte)
## ^-------- unit_length (4-byte)
## ^--- version (2-byte)
## ^- unit_type (1-byte)
# DWARFV5-HEADER-NEXT: 0x00000020 08341200 000df0ad baefbead de180000 .4..............
## ^- address_size (1-byte)
## ^-------- debug_abbrev_offset (4-byte)
## ^----------------- type_signature (8-byte)
## \/ ^----- type_offset (4-byte)
# DWARFV5-HEADER-NEXT: 0x00000030 0000ffff ffff1d00 00000000 00000500 ................
## ^- End of children (1-byte)
## ^-------------------------- unit_length (12-byte)
## ^--- version (2-byte)
# DWARFV5-HEADER-NEXT: 0x00000040 02083412 00000000 00000df0 adbaefbe ..4.............
## ^- unit_type (1-byte)
## ^- address_size (1-byte)
## ^----------------- debug_abbrev_offset (8-byte)
## \/-- ^------------ type_signature (8-byte)
# DWARFV5-HEADER-NEXT: 0x00000050 adde2800 00000000 00000011 00000005 ..(.............
## ^----------------- type_offset (8-byte)
## ^- End of children (1-byte)
## ^-------- unit_length (4-byte)
## \/ ^- version (2-byte)
# DWARFV5-HEADER-NEXT: 0x00000060 00040834 1200000d f0adbaef beadde00 ...4............
## ^- unit_type (1-byte)
## ^- address_size (1-byte)
## ^-------- debug_abbrev_offset (4-byte)
## ^----------------- type_signature (8-byte)
## ^- End of children (1-byte)



--- !ELF
FileHeader:
Expand All @@ -686,12 +715,33 @@ FileHeader:
Type: ET_EXEC
DWARF:
debug_info:
- Format: DWARF64
Version: 5
UnitType: DW_UT_compile
AbbrOffset: 0x1234
Entries:
- AbbrCode: 0
- Version: 5
UnitType: DW_UT_type
AbbrOffset: 0x1234
TypeSignature: 0xdeadbeefbaadf00d
TypeOffset: 24
Entries:
- AbbrCode: 0
- Format: DWARF64
Length: 0x0c
Version: 5
UnitType: DW_UT_type
AbbrOffset: 0x1234
Entries: []
Version: 5
UnitType: DW_UT_type
AbbrOffset: 0x1234
TypeSignature: 0xdeadbeefbaadf00d
TypeOffset: 40
Entries:
- AbbrCode: 0
- Version: 5
UnitType: DW_UT_skeleton
AbbrOffset: 0x1234
DwoID: 0xdeadbeefbaadf00d
Entries:
- AbbrCode: 0

## DWARFv4 unit header.

Expand Down
2 changes: 1 addition & 1 deletion llvm/tools/obj2yaml/dwarf2yaml.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -338,7 +338,7 @@ void dumpDebugInfo(DWARFContext &DCtx, DWARFYAML::Data &Y) {

NewUnit.Entries.push_back(NewEntry);
}
Y.CompileUnits.push_back(NewUnit);
Y.Units.push_back(NewUnit);
}
}

Expand Down

0 comments on commit af14da5

Please sign in to comment.