[llvm-gsymutil] Fix assert failure on FileEntry.Dir empty #79926
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Summary: FileEntry.Dir can be empty if debug info only contains relative path. This caused an assertion failure when gsym segmentation is trying to copy a file entry with empty dir. As the fitst entry of StringTable is always empty (and is preserved), `StringOffsetMap` doesn't have key 0. Hence, `find(0)` returns `End` and `operator->()` fails the assertion Test Plan: ./bin/llvm-lit -sv llvm/test/tools/llvm-gsymutil/X86/elf-empty-dir.yaml
|
@llvm/pr-subscribers-debuginfo Author: kusmour (kusmour) ChangesSummary: Test Plan: Full diff: https://github.com/llvm/llvm-project/pull/79926.diff 2 Files Affected:
diff --git a/llvm/lib/DebugInfo/GSYM/GsymCreator.cpp b/llvm/lib/DebugInfo/GSYM/GsymCreator.cpp
index ee7b0efba5ea47..74138755090a45 100644
--- a/llvm/lib/DebugInfo/GSYM/GsymCreator.cpp
+++ b/llvm/lib/DebugInfo/GSYM/GsymCreator.cpp
@@ -55,7 +55,10 @@ uint32_t GsymCreator::copyFile(const GsymCreator &SrcGC, uint32_t FileIdx) {
return 0;
const FileEntry SrcFE = SrcGC.Files[FileIdx];
// Copy the strings for the file and then add the newly converted file entry.
- uint32_t Dir = StrTab.add(SrcGC.StringOffsetMap.find(SrcFE.Dir)->second);
+ uint32_t Dir =
+ SrcFE.Dir == 0
+ ? 0
+ : StrTab.add(SrcGC.StringOffsetMap.find(SrcFE.Dir)->second);
uint32_t Base = StrTab.add(SrcGC.StringOffsetMap.find(SrcFE.Base)->second);
FileEntry DstFE(Dir, Base);
return insertFileEntry(DstFE);
diff --git a/llvm/test/tools/llvm-gsymutil/X86/elf-empty-dir.yaml b/llvm/test/tools/llvm-gsymutil/X86/elf-empty-dir.yaml
new file mode 100644
index 00000000000000..6f6acf88004884
--- /dev/null
+++ b/llvm/test/tools/llvm-gsymutil/X86/elf-empty-dir.yaml
@@ -0,0 +1,108 @@
+## Test converting DWARF using relative path
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-gsymutil --convert %t -o %t.gsym --segment-size=100000 --num-threads=80 --quiet 2>&1 | FileCheck %s --check-prefix=CONVERT
+
+# CONVERT: Input file: {{.*\.yaml\.tmp}}
+# CONVERT: Output file (x86_64): {{.*\.yaml\.tmp\.gsym}}
+# CONVERT: Pruned 0 functions, ended with 1 total
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_EXEC
+ Machine: EM_X86_64
+DWARF:
+ debug_str:
+ - ''
+ - main.cpp
+ - foo
+ debug_abbrev:
+ - ID: 0
+ Table:
+ - Code: 0x1
+ Tag: DW_TAG_compile_unit
+ Children: DW_CHILDREN_yes
+ Attributes:
+ - Attribute: DW_AT_name
+ Form: DW_FORM_strp
+ - Attribute: DW_AT_language
+ Form: DW_FORM_udata
+ - Attribute: DW_AT_stmt_list
+ Form: DW_FORM_sec_offset
+ - Code: 0x2
+ Tag: DW_TAG_subprogram
+ Children: DW_CHILDREN_no
+ Attributes:
+ - Attribute: DW_AT_name
+ Form: DW_FORM_strp
+ - Attribute: DW_AT_low_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ debug_info:
+ - Length: 0x27
+ Version: 4
+ AbbrevTableID: 0
+ AbbrOffset: 0x0
+ AddrSize: 8
+ Entries:
+ - AbbrCode: 0x1
+ Values:
+ - Value: 0x1
+ - Value: 0x2
+ - Value: 0x0
+ - AbbrCode: 0x2
+ Values:
+ - Value: 0xA
+ - Value: 0x1000
+ - Value: 0x1050
+ - AbbrCode: 0x0
+ debug_line:
+ - Length: 66
+ Version: 2
+ PrologueLength: 31
+ MinInstLength: 1
+ DefaultIsStmt: 1
+ LineBase: 251
+ LineRange: 14
+ OpcodeBase: 13
+ StandardOpcodeLengths: [ 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1 ]
+ Files:
+ - Name: main.cpp
+ DirIdx: 0
+ ModTime: 0
+ Length: 0
+ Opcodes:
+ - Opcode: DW_LNS_extended_op
+ ExtLen: 9
+ SubOpcode: DW_LNE_set_address
+ Data: 4096
+ - Opcode: DW_LNS_advance_line
+ SData: 9
+ Data: 0
+ - Opcode: DW_LNS_copy
+ Data: 0
+ - Opcode: DW_LNS_advance_pc
+ Data: 16
+ - Opcode: DW_LNS_advance_line
+ SData: 1
+ Data: 0
+ - Opcode: DW_LNS_copy
+ Data: 0
+ - Opcode: DW_LNS_advance_line
+ SData: 1
+ Data: 0
+ - Opcode: DW_LNS_copy
+ Data: 0
+ - Opcode: DW_LNS_advance_pc
+ Data: 64
+ - Opcode: DW_LNS_advance_line
+ SData: 1
+ Data: 0
+ - Opcode: DW_LNS_extended_op
+ ExtLen: 1
+ SubOpcode: DW_LNE_end_sequence
+ Data: 0
+...
|
dcci
approved these changes
Jan 30, 2024
clayborg
reviewed
Jan 30, 2024
| ## Test converting DWARF using relative path | ||
|
|
||
| # RUN: yaml2obj %s -o %t | ||
| # RUN: llvm-gsymutil --convert %t -o %t.gsym --segment-size=100000 --num-threads=80 --quiet 2>&1 | FileCheck %s --check-prefix=CONVERT |
There was a problem hiding this comment.
Don't specify the number of threads, they will automatically be set to a good value.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Summary:
FileEntry.Dir can be empty if debug info only contains relative path. This caused an assertion failure when gsym segmentation is trying to copy a file entry with empty dir. As the fitst entry of StringTable is always empty (and is preserved),
StringOffsetMapdoesn't have key 0. Hence,find(0)returnsEndandoperator->()fails the assertionTest Plan:
./bin/llvm-lit -sv llvm/test/tools/llvm-gsymutil/X86/elf-empty-dir.yaml