Add support for verifying local type units in .debug_names. #101133
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labath
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Jul 30, 2024
| @@ -1512,7 +1512,8 @@ 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", | |||
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Suggested change
| "and abbreviation {1:x} has no {2} attribute.\n", | |
| "and abbreviation {1:x} has no type or compile unit attribute.\n", |
.. or something like that. Basically to have the error message say that we're not looking for just the compile unit attr.
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This error message is only for DW_IDX_comp_unit missing when we have multiple compile units. This code change stops this error being emitted if we have a name entry that only has a DW_IDX_type_unit, which is ok.
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Yes, but is it the correct error message in the presence of type units? Like, if you have an index entry with only a DW_IDX_die_offset value, can you be certain that it's missing a DW_IDX_compile_unit value? I think not because, for all we know, it could be a type entry with a "forgotten" DW_IDX_type_unit key.
That's the distinction I wanted to capture here...
|
@llvm/pr-subscribers-debuginfo Author: Greg Clayton (clayborg) ChangesThis patch adds support for verifying local type units in .debug_names section. It adds a test to test if the TU index is valid, and a test that tests that an error is found inside the name entry for a type unit. We don't need to test all other errors in the name entry because these are essentially identical to compile unit entries, they just use a different DWARF unit offset index. Full diff: https://github.com/llvm/llvm-project/pull/101133.diff 3 Files Affected:
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index a804deb446186..2bf3eaf67bc1a 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -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;
}
@@ -1512,7 +1512,8 @@ 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",
@@ -1574,8 +1575,8 @@ 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();
@@ -1596,18 +1597,35 @@ 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", [&]() {
@@ -1618,12 +1636,12 @@ 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;
diff --git a/llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-die.yaml b/llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-die.yaml
new file mode 100644
index 0000000000000..f85d97a555d80
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-die.yaml
@@ -0,0 +1,116 @@
+# 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 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
+ EntSize: 0x1
+ Content: 46616365626F6F6B20636C616E672076657273696F6E2031352E302E30202868747470733A2F2F6769742E696E7465726E616C2E7466626E772E6E65742F7265706F732F6769742F726F2F6F736D6574612F65787465726E616C2F6C6C766D2D70726F6A656374203864356561396432616431633161356139303862623632343663303261626162323235643562633829004C696E6B65723A204C4C442031392E302E300000
+ - Name: .debug_line
+ Type: SHT_PROGBITS
+ AddressAlign: 0x1
+ Content: 590000000500080037000000010101FB0E0D00010101010000000100000101011F010900000003011F020F051E01000000000014E7C4DFD187393499D4332D94A1154D040000090260112000000000001405030AAE060B2E0202000101
+ - Name: .debug_line_str
+ Type: SHT_PROGBITS
+ Flags: [ SHF_MERGE, SHF_STRINGS ]
+ AddressAlign: 0x1
+ EntSize: 0x1
+ 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
+...
diff --git a/llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-tu-index.yaml b/llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-tu-index.yaml
new file mode 100644
index 0000000000000..899c4616c8e2d
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/debug-names-local-tu-bad-tu-index.yaml
@@ -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:
+ - 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: 900000000500000001000000010000000000000003000000030000001B000000080000004C4C564D303730302A000000000000000100000002000000030000008973880B6A7F9A7C3080880BD10000009F000000A400000000000000070000000D0000000113020B031304190000022E03130419000003240313041900000001012500000000022300000000033E000000000000
+ - Name: .comment
+ Type: SHT_PROGBITS
+ Flags: [ SHF_MERGE, SHF_STRINGS ]
+ AddressAlign: 0x1
+ EntSize: 0x1
+ Content: 46616365626F6F6B20636C616E672076657273696F6E2031352E302E30202868747470733A2F2F6769742E696E7465726E616C2E7466626E772E6E65742F7265706F732F6769742F726F2F6F736D6574612F65787465726E616C2F6C6C766D2D70726F6A656374203864356561396432616431633161356139303862623632343663303261626162323235643562633829004C696E6B65723A204C4C442031392E302E300000
+ - Name: .debug_line
+ Type: SHT_PROGBITS
+ AddressAlign: 0x1
+ Content: 590000000500080037000000010101FB0E0D00010101010000000100000101011F010900000003011F020F051E01000000000014E7C4DFD187393499D4332D94A1154D040000090260112000000000001405030AAE060B2E0202000101
+ - Name: .debug_line_str
+ Type: SHT_PROGBITS
+ Flags: [ SHF_MERGE, SHF_STRINGS ]
+ AddressAlign: 0x1
+ EntSize: 0x1
+ 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
+...
|
|
Added the tests! |
labath
approved these changes
Jul 31, 2024
| @@ -1512,7 +1512,8 @@ 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", | |||
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Yes, but is it the correct error message in the presence of type units? Like, if you have an index entry with only a DW_IDX_die_offset value, can you be certain that it's missing a DW_IDX_compile_unit value? I think not because, for all we know, it could be a type entry with a "forgotten" DW_IDX_type_unit key.
That's the distinction I wanted to capture here...
| @@ -0,0 +1,116 @@ | |||
| # RUN: yaml2obj %s -o - | not llvm-dwarfdump -verify - | FileCheck %s | |||
There was a problem hiding this comment.
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?
This patch adds support for verifying local type units in .debug_names section. It adds a test to test if the TU index is valid, and a test that tests that an error is found inside the name entry for a type unit. We don't need to test all other errors in the name entry because these are essentially identical to compile unit entries, they just use a different DWARF unit offset index.
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This patch adds support for verifying local type units in .debug_names section. It adds a test to test if the TU index is valid, and a test that tests that an error is found inside the name entry for a type unit. We don't need to test all other errors in the name entry because these are essentially identical to compile unit entries, they just use a different DWARF unit offset index.