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Merged
merged 3 commits into from
Aug 1, 2024
Merged

Add support for verifying local type units in .debug_names. #101133

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fe6a57f
Add support for verifying local type units in .debug_names.
clayborg Jul 30, 2024
b47221b
Add missing tests.
clayborg Jul 30, 2024
c73941f
Address more user feedback.
clayborg Aug 1, 2024
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47 changes: 33 additions & 14 deletions llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1481,9 +1481,9 @@ unsigned DWARFVerifier::verifyNameIndexAttribute(

unsigned
DWARFVerifier::verifyNameIndexAbbrevs(const DWARFDebugNames::NameIndex &NI) {
if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0) {
warn() << formatv("Name Index @ {0:x}: Verifying indexes of type units is "
"not currently supported.\n",
if (NI.getForeignTUCount() > 0) {
warn() << formatv("Name Index @ {0:x}: Verifying indexes of foreign type "
"units is not currently supported.\n",
NI.getUnitOffset());
return 0;
}
Expand Down Expand Up @@ -1512,10 +1512,12 @@ DWARFVerifier::verifyNameIndexAbbrevs(const DWARFDebugNames::NameIndex &NI) {
NumErrors += verifyNameIndexAttribute(NI, Abbrev, AttrEnc);
}

if (NI.getCUCount() > 1 && !Attributes.count(dwarf::DW_IDX_compile_unit)) {
if (NI.getCUCount() > 1 && !Attributes.count(dwarf::DW_IDX_compile_unit) &&
!Attributes.count(dwarf::DW_IDX_type_unit)) {
ErrorCategory.Report("Abbreviation contains no attribute", [&]() {
error() << formatv("NameIndex @ {0:x}: Indexing multiple compile units "
"and abbreviation {1:x} has no {2} attribute.\n",
"and abbreviation {1:x} has no DW_IDX_compile_unit "
"or DW_IDX_type_unit attribute.\n",
NI.getUnitOffset(), Abbrev.Code,
dwarf::DW_IDX_compile_unit);
});
Expand Down Expand Up @@ -1574,8 +1576,8 @@ static SmallVector<std::string, 3> getNames(const DWARFDie &DIE,
unsigned DWARFVerifier::verifyNameIndexEntries(
const DWARFDebugNames::NameIndex &NI,
const DWARFDebugNames::NameTableEntry &NTE) {
// Verifying type unit indexes not supported.
if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0)
// Verifying foreign type unit indexes not supported.
if (NI.getForeignTUCount() > 0)
return 0;

const char *CStr = NTE.getString();
Expand All @@ -1596,18 +1598,35 @@ unsigned DWARFVerifier::verifyNameIndexEntries(
Expected<DWARFDebugNames::Entry> EntryOr = NI.getEntry(&NextEntryID);
for (; EntryOr; ++NumEntries, EntryID = NextEntryID,
EntryOr = NI.getEntry(&NextEntryID)) {
uint32_t CUIndex = *EntryOr->getCUIndex();
if (CUIndex > NI.getCUCount()) {

std::optional<uint64_t> CUIndex = EntryOr->getCUIndex();
std::optional<uint64_t> TUIndex = EntryOr->getLocalTUIndex();
if (CUIndex && *CUIndex >= NI.getCUCount()) {
ErrorCategory.Report("Name Index entry contains invalid CU index", [&]() {
error() << formatv("Name Index @ {0:x}: Entry @ {1:x} contains an "
"invalid CU index ({2}).\n",
NI.getUnitOffset(), EntryID, CUIndex);
NI.getUnitOffset(), EntryID, *CUIndex);
});
++NumErrors;
continue;
}
uint64_t CUOffset = NI.getCUOffset(CUIndex);
uint64_t DIEOffset = CUOffset + *EntryOr->getDIEUnitOffset();
if (TUIndex && *TUIndex >= NI.getLocalTUCount()) {
ErrorCategory.Report("Name Index entry contains invalid TU index", [&]() {
error() << formatv("Name Index @ {0:x}: Entry @ {1:x} contains an "
"invalid TU index ({2}).\n",
NI.getUnitOffset(), EntryID, *TUIndex);
});
++NumErrors;
continue;
}
std::optional<uint64_t> UnitOffset;
if (TUIndex)
UnitOffset = NI.getLocalTUOffset(*TUIndex);
else if (CUIndex)
UnitOffset = NI.getCUOffset(*CUIndex);
if (!UnitOffset)
continue;
uint64_t DIEOffset = *UnitOffset + *EntryOr->getDIEUnitOffset();
DWARFDie DIE = DCtx.getDIEForOffset(DIEOffset);
if (!DIE) {
ErrorCategory.Report("NameIndex references nonexistent DIE", [&]() {
Expand All @@ -1618,12 +1637,12 @@ unsigned DWARFVerifier::verifyNameIndexEntries(
++NumErrors;
continue;
}
if (DIE.getDwarfUnit()->getOffset() != CUOffset) {
if (DIE.getDwarfUnit()->getOffset() != *UnitOffset) {
ErrorCategory.Report("Name index contains mismatched CU of DIE", [&]() {
error() << formatv(
"Name Index @ {0:x}: Entry @ {1:x}: mismatched CU of "
"DIE @ {2:x}: index - {3:x}; debug_info - {4:x}.\n",
NI.getUnitOffset(), EntryID, DIEOffset, CUOffset,
NI.getUnitOffset(), EntryID, DIEOffset, *UnitOffset,
DIE.getDwarfUnit()->getOffset());
});
++NumErrors;
Expand Down
2 changes: 1 addition & 1 deletion llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-abbrev-forms.s
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Original file line number Diff line number Diff line change
Expand Up @@ -9,7 +9,7 @@
# CHECK: NameIndex @ 0x0: Abbreviation 0x1: DW_IDX_die_offset uses an unknown form: DW_FORM_unknown_1fff.
# CHECK: warning: NameIndex @ 0x0: Abbreviation 0x3 references an unknown tag: DW_TAG_unknown_8080.
# CHECK: error: NameIndex @ 0x0: Abbreviation 0x5 has no DW_IDX_die_offset attribute.
# CHECK: error: NameIndex @ 0x55: Indexing multiple compile units and abbreviation 0x1 has no DW_IDX_compile_unit attribute.
# CHECK: error: NameIndex @ 0x55: Indexing multiple compile units and abbreviation 0x1 has no DW_IDX_compile_unit or DW_IDX_type_unit attribute.

.section .debug_str,"MS",@progbits,1
.Lstring_producer:
Expand Down
116 changes: 116 additions & 0 deletions llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-die.yaml
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Original file line number Diff line number Diff line change
@@ -0,0 +1,116 @@
# RUN: yaml2obj %s -o - | not llvm-dwarfdump -verify - | FileCheck %s
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Judging by the strings in this file, you've produced this by running (meta:P) clang over some file, and then tweaking the output. Would it be possible to make the same modifications on the intermediate assembly file instead?

I see there is already a precedent for yaml input files in this folder, so I wouldn't say this is a hard requirement, but I think it'd much easier to see what's going on here by looking at the (annotated) assembly than at a raw hex dump. (At this point, I've gotten pretty good at reading dwarf from assembly, but I'm not l33t enough to do it from hex :P)

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This is a linked executable. It doesn't work on .o files with multiple DWARF units. I tried to make one and ended up with:

Verifying /Users/gclayton/Documents/src/github/Debug/test/tools/llvm-dwarfdump/X86/Output/debug-names-verify-tu-bad-die.s.tmp:  file format elf64-x86-64
Verifying .debug_abbrev...
Verifying .debug_info Unit Header Chain...
Verifying .debug_types Unit Header Chain...
Verifying non-dwo Units...
Verifying unit: 1 / 2
Verifying unit: 2 / 2, "main.cpp"
Verifying dwo Units...
Verifying .debug_line...
warning: .debug_line[0x00000000].prologue.file_names[1] is a duplicate of file_names[0]
Verifying .debug_str_offsets...
Verifying .debug_names...
error: Name Index @ 0x0: Entry @ 0x86: mismatched Tag of DIE @ 0x23: index - DW_TAG_subprogram; debug_info - DW_TAG_structure_type.
error: Name Index @ 0x0: Entry @ 0x86: mismatched Name of DIE @ 0x23: index - main; debug_info - Foo.
error: Aggregated error counts:
error: Name Index contains mismatched Tag of DIE occurred 1 time(s).
error: Name Index contains mismatched name of DIE occurred 1 time(s).
Errors detected.

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And this was for a .o file straight from the compiler. I am guessing llvm-dwarfdump might not be applying relocations, but that is beyond the scope of this patch.

Is there a way to get a .s file for linked executable?

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There's no way to get a .s version of a linked executable. I guess it's possible there's something wrong with the relocations, though I'm somewhat surprised by that since llvm-dwarfdump is reguarly used (both in tests and in real word) on unlinked files. What's the input you used to reproduce this?


# Verifying local type units. Local type units and compile units are identical
# except that the DWARF Unit offset for the type unit is specified using a
# DW_IDX_type_unit. This is a single test that tests if we get an error for a
# local type unit. We only need to verify that errors work for type units and
# we can rely on the test for compile units to verify all other errors that can
# happen in the .debug_names entries.

# CHECK: Verifying .debug_names...
# CHECK: error: Name Index @ 0x0: Entry @ 0x7f references a non-existing DIE @ 0x25.
# CHECK: error: Aggregated error counts:
# CHECK: error: NameIndex references nonexistent DIE occurred 1 time(s).
# Errors detected.

--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
ProgramHeaders:
- Type: PT_PHDR
Flags: [ PF_R ]
VAddr: 0x200040
Align: 0x8
Offset: 0x40
- Type: PT_LOAD
Flags: [ PF_R ]
FirstSec: .eh_frame
LastSec: .eh_frame
VAddr: 0x200000
Align: 0x1000
Offset: 0x0
- Type: PT_LOAD
Flags: [ PF_X, PF_R ]
FirstSec: .text
LastSec: .text
VAddr: 0x201160
Align: 0x1000
Offset: 0x160
- Type: PT_GNU_STACK
Flags: [ PF_W, PF_R ]
Align: 0x0
Offset: 0x0
Sections:
- Name: .eh_frame
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC ]
Address: 0x200120
AddressAlign: 0x8
Content: 1400000000000000017A5200017810011B0C0708900100001C0000001C000000201000000F00000000410E108602430D064A0C070800000000000000
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x201160
AddressAlign: 0x10
Content: 554889E5C745FC0000000031C05DC3
- Name: .debug_info
Type: SHT_PROGBITS
AddressAlign: 0x1
Content: 260000000500020800000000F23532F3E4235D67230000000121000000000008000000020506010001004800000005000108000000000300210001080000000000000002000F0000000800000004000F00000001560300033E0000000502917B05000442000000000604050407F23532F3E4235D6700
- Name: .debug_abbrev
Type: SHT_PROGBITS
AddressAlign: 0x1
Content: 0141011305101772170000021300360B03250B0B3A0B3B0B0000031101252513050325721710171B25111B120673170000042E01111B1206401803253A0B3B0B49133F190000053400021803253A0B3B0B4913000006240003253E0B0B0B00000713003C196920000000
- Name: .debug_str_offsets
Type: SHT_PROGBITS
AddressAlign: 0x1
Content: 20000000050000000400000096000000A80000009F000000A400000000000000D1000000
- Name: .debug_names
Type: SHT_PROGBITS
AddressAlign: 0x4
Content: 900000000500000001000000010000000000000003000000030000001B000000080000004C4C564D303730302A000000000000000100000002000000030000008973880B6A7F9A7C3080880BD10000009F000000A400000000000000070000000D0000000113020B031304190000022E03130419000003240313041900000001002500000000022300000000033E000000000000
- Name: .comment
Type: SHT_PROGBITS
Flags: [ SHF_MERGE, SHF_STRINGS ]
AddressAlign: 0x1
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Content: 46616365626F6F6B20636C616E672076657273696F6E2031352E302E30202868747470733A2F2F6769742E696E7465726E616C2E7466626E772E6E65742F7265706F732F6769742F726F2F6F736D6574612F65787465726E616C2F6C6C766D2D70726F6A656374203864356561396432616431633161356139303862623632343663303261626162323235643562633829004C696E6B65723A204C4C442031392E302E300000
- Name: .debug_line
Type: SHT_PROGBITS
AddressAlign: 0x1
Content: 590000000500080037000000010101FB0E0D00010101010000000100000101011F010900000003011F020F051E01000000000014E7C4DFD187393499D4332D94A1154D040000090260112000000000001405030AAE060B2E0202000101
- Name: .debug_line_str
Type: SHT_PROGBITS
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Content: 6D61696E2E637070002F55736572732F67636C6179746F6E2F446F63756D656E74732F7372632F7665726966792D74757300
Symbols:
- Name: main.cpp
Type: STT_FILE
Index: SHN_ABS
- Name: main
Type: STT_FUNC
Section: .text
Binding: STB_GLOBAL
Value: 0x201160
Size: 0xF
DWARF:
debug_str:
- foo
- 'Facebook clang version 15.0.0 (https://git.internal.tfbnw.net/repos/git/ro/osmeta/external/llvm-project 8d5ea9d2ad1c1a5a908bb6246c02abab225d5bc8)'
- main.cpp
- main
- int
- '/Users/gclayton/Documents/src/verify-tus'
- Foo
debug_addr:
- Length: 0xC
Version: 0x5
AddressSize: 0x8
Entries:
- Address: 0x201160
...
114 changes: 114 additions & 0 deletions llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-tu-index.yaml
View file
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Original file line number Diff line number Diff line change
@@ -0,0 +1,114 @@
# RUN: yaml2obj %s -o - | not llvm-dwarfdump -verify - | FileCheck %s

# Verifying local type units. Local type units and compile units are identical
# except that the DWARF Unit offset for the type unit is specified using a
# DW_IDX_type_unit. This is a single test that tests that the type unit index
# in the DW_IDX_type_unit value is valid.

# CHECK: Verifying .debug_names...
# CHECK: error: Name Index @ 0x0: Entry @ 0x7f contains an invalid TU index (1).
# CHECK: error: Aggregated error counts:
# CHECK: error: Name Index entry contains invalid TU index occurred 1 time(s).
# Errors detected.

--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
ProgramHeaders:
- Type: PT_PHDR
Flags: [ PF_R ]
VAddr: 0x200040
Align: 0x8
Offset: 0x40
- Type: PT_LOAD
Flags: [ PF_R ]
FirstSec: .eh_frame
LastSec: .eh_frame
VAddr: 0x200000
Align: 0x1000
Offset: 0x0
- Type: PT_LOAD
Flags: [ PF_X, PF_R ]
FirstSec: .text
LastSec: .text
VAddr: 0x201160
Align: 0x1000
Offset: 0x160
- Type: PT_GNU_STACK
Flags: [ PF_W, PF_R ]
Align: 0x0
Offset: 0x0
Sections:
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Type: SHT_PROGBITS
Flags: [ SHF_ALLOC ]
Address: 0x200120
AddressAlign: 0x8
Content: 1400000000000000017A5200017810011B0C0708900100001C0000001C000000201000000F00000000410E108602430D064A0C070800000000000000
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x201160
AddressAlign: 0x10
Content: 554889E5C745FC0000000031C05DC3
- Name: .debug_info
Type: SHT_PROGBITS
AddressAlign: 0x1
Content: 260000000500020800000000F23532F3E4235D67230000000121000000000008000000020506010001004800000005000108000000000300210001080000000000000002000F0000000800000004000F00000001560300033E0000000502917B05000442000000000604050407F23532F3E4235D6700
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Type: SHT_PROGBITS
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Symbols:
- Name: main.cpp
Type: STT_FILE
Index: SHN_ABS
- Name: main
Type: STT_FUNC
Section: .text
Binding: STB_GLOBAL
Value: 0x201160
Size: 0xF
DWARF:
debug_str:
- foo
- 'Facebook clang version 15.0.0 (https://git.internal.tfbnw.net/repos/git/ro/osmeta/external/llvm-project 8d5ea9d2ad1c1a5a908bb6246c02abab225d5bc8)'
- main.cpp
- main
- int
- '/Users/gclayton/Documents/src/verify-tus'
- Foo
debug_addr:
- Length: 0xC
Version: 0x5
AddressSize: 0x8
Entries:
- Address: 0x201160
...
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