From 4607449b18e0c2e0d2bc5e8829456399f3573626 Mon Sep 17 00:00:00 2001 From: David Blaikie Date: Fri, 9 Jul 2021 18:27:31 -0700 Subject: [PATCH] llvm-symbolizer: Fix "start file" to work with Split DWARF A followup to the feature added in 69da27c7496ea373567ce5121e6fe8613846e7a5 that added the optional "start file name" to match "start line" - but this didn't work with Split DWARF because of the need for the decl file number resolution code to refer back to the skeleton unit to find its .debug_line contribution. So this patch adds the necessary infrastructure to track the skeleton unit corresponding to a split full unit for the purpose of this lookup. --- include/llvm/DebugInfo/DWARF/DWARFUnit.h | 7 + lib/DebugInfo/DWARF/DWARFDie.cpp | 13 +- lib/DebugInfo/DWARF/DWARFUnit.cpp | 2 + test/DebugInfo/X86/symbolize_function_start.s | 211 ++++++++++++++++++ 4 files changed, 229 insertions(+), 4 deletions(-) create mode 100644 test/DebugInfo/X86/symbolize_function_start.s diff --git a/include/llvm/DebugInfo/DWARF/DWARFUnit.h b/include/llvm/DebugInfo/DWARF/DWARFUnit.h index a340fb3f028..1292bfbc059 100644 --- a/include/llvm/DebugInfo/DWARF/DWARFUnit.h +++ b/include/llvm/DebugInfo/DWARF/DWARFUnit.h @@ -218,6 +218,7 @@ class DWARFUnit { StringRef StringSection; const DWARFSection &StringOffsetSection; const DWARFSection *AddrOffsetSection; + DWARFUnit *SU; Optional AddrOffsetSectionBase; bool isLittleEndian; bool IsDWO; @@ -301,6 +302,12 @@ public: return StringOffsetSection; } + void setSkeletonUnit(DWARFUnit *SU) { this->SU = SU; } + // Returns itself if not using Split DWARF, or if the unit is a skeleton unit + // - otherwise returns the split full unit's corresponding skeleton, if + // available. + DWARFUnit *getLinkedUnit() { return IsDWO ? SU : this; } + void setAddrOffsetSection(const DWARFSection *AOS, uint64_t Base) { AddrOffsetSection = AOS; AddrOffsetSectionBase = Base; diff --git a/lib/DebugInfo/DWARF/DWARFDie.cpp b/lib/DebugInfo/DWARF/DWARFDie.cpp index 79438dcf843..d82de9fefa6 100644 --- a/lib/DebugInfo/DWARF/DWARFDie.cpp +++ b/lib/DebugInfo/DWARF/DWARFDie.cpp @@ -571,11 +571,16 @@ uint64_t DWARFDie::getDeclLine() const { std::string DWARFDie::getDeclFile(DILineInfoSpecifier::FileLineInfoKind Kind) const { + auto D = getAttributeValueAsReferencedDie(DW_AT_abstract_origin); + if (!D) + D = *this; std::string FileName; - if (auto DeclFile = toUnsigned(findRecursively(DW_AT_decl_file))) { - if (const auto *LT = U->getContext().getLineTableForUnit(U)) { - LT->getFileNameByIndex(*DeclFile, U->getCompilationDir(), Kind, FileName); - } + if (auto DeclFile = toUnsigned(D.find(DW_AT_decl_file))) { + if (const auto *LineTable = + getDwarfUnit()->getContext().getLineTableForUnit( + D.getDwarfUnit()->getLinkedUnit())) + LineTable->getFileNameByIndex( + *DeclFile, D.getDwarfUnit()->getCompilationDir(), Kind, FileName); } return FileName; } diff --git a/lib/DebugInfo/DWARF/DWARFUnit.cpp b/lib/DebugInfo/DWARF/DWARFUnit.cpp index 57ac0a51698..79d18faf144 100644 --- a/lib/DebugInfo/DWARF/DWARFUnit.cpp +++ b/lib/DebugInfo/DWARF/DWARFUnit.cpp @@ -388,6 +388,7 @@ void DWARFUnit::clear() { RangeSectionBase = 0; LocSectionBase = 0; AddrOffsetSectionBase = None; + SU = nullptr; clearDIEs(false); DWO.reset(); } @@ -586,6 +587,7 @@ bool DWARFUnit::parseDWO() { if (!DWOCU) return false; DWO = std::shared_ptr(std::move(DWOContext), DWOCU); + DWO->setSkeletonUnit(this); // Share .debug_addr and .debug_ranges section with compile unit in .dwo if (AddrOffsetSectionBase) DWO->setAddrOffsetSection(AddrOffsetSection, *AddrOffsetSectionBase); diff --git a/test/DebugInfo/X86/symbolize_function_start.s b/test/DebugInfo/X86/symbolize_function_start.s new file mode 100644 index 00000000000..df6caa482a6 --- /dev/null +++ b/test/DebugInfo/X86/symbolize_function_start.s @@ -0,0 +1,211 @@ +# RUN: rm -rf %t +# RUN: mkdir %t +# RUN: llvm-mc -filetype=obj -triple=x86_64 -dwarf-version=4 %s -o %t/test.o +# RUN: cd %t +# RUN: llvm-symbolizer -verbose 0x0 -obj=test.o | FileCheck --check-prefix=SYM %s +# RUN: llvm-dwarfdump -lookup=0x1 test.o | FileCheck --check-prefix=LOOKUP %s + +# SYM: Filename: ./././test.h +# SYM: Function start filename: ./test.cpp + +# LOOKUP: Line info: line 0, column 0, start file 'test.cpp', start line 1 + + + .text + .file "test.cpp" + .globl _Z2f1v # -- Begin function _Z2f1v + .p2align 4, 0x90 + .type _Z2f1v,@function +_Z2f1v: # @_Z2f1v +.Lfunc_begin0: + .file 1 "." "test.cpp" + .loc 1 1 0 # test.cpp:1:0 + .cfi_startproc +# %bb.0: # %entry + .file 2 "." "./test.h" + .loc 2 1 1 prologue_end # ./test.h:1:1 + xorl %eax, %eax + retq +.Ltmp0: +.Lfunc_end0: + .size _Z2f1v, .Lfunc_end0-_Z2f1v + .cfi_endproc + # -- End function + .section .debug_abbrev,"",@progbits + .byte 1 # Abbreviation Code + .byte 17 # DW_TAG_compile_unit + .byte 0 # DW_CHILDREN_no + .byte 16 # DW_AT_stmt_list + .byte 23 # DW_FORM_sec_offset + .byte 27 # DW_AT_comp_dir + .byte 14 # DW_FORM_strp + .ascii "\264B" # DW_AT_GNU_pubnames + .byte 25 # DW_FORM_flag_present + .ascii "\260B" # DW_AT_GNU_dwo_name + .byte 14 # DW_FORM_strp + .ascii "\261B" # DW_AT_GNU_dwo_id + .byte 7 # DW_FORM_data8 + .byte 17 # DW_AT_low_pc + .byte 1 # DW_FORM_addr + .byte 18 # DW_AT_high_pc + .byte 6 # DW_FORM_data4 + .ascii "\263B" # DW_AT_GNU_addr_base + .byte 23 # DW_FORM_sec_offset + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 0 # EOM(3) + .section .debug_info,"",@progbits +.Lcu_begin0: + .long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit +.Ldebug_info_start0: + .short 4 # DWARF version number + .long .debug_abbrev # Offset Into Abbrev. Section + .byte 8 # Address Size (in bytes) + .byte 1 # Abbrev [1] 0xb:0x25 DW_TAG_compile_unit + .long .Lline_table_start0 # DW_AT_stmt_list + .long .Lskel_string0 # DW_AT_comp_dir + # DW_AT_GNU_pubnames + .long .Lskel_string1 # DW_AT_GNU_dwo_name + .quad 7198491773836599109 # DW_AT_GNU_dwo_id + .quad .Lfunc_begin0 # DW_AT_low_pc + .long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc + .long .Laddr_table_base0 # DW_AT_GNU_addr_base +.Ldebug_info_end0: + .section .debug_str,"MS",@progbits,1 +.Lskel_string0: + .asciz "." # string offset=0 +.Lskel_string1: + .asciz "test.o" # string offset=2 + .section .debug_str.dwo,"eMS",@progbits,1 +.Linfo_string0: + .asciz "_Z2f1v" # string offset=0 +.Linfo_string1: + .asciz "f1" # string offset=7 +.Linfo_string2: + .asciz "int" # string offset=10 +.Linfo_string3: + .asciz "clang version 13.0.0 (git@github.com:llvm/llvm-project.git 882ee7fbd6fc989fba53f3d9672440771feb80f5)" # string offset=14 +.Linfo_string4: + .asciz "test.cpp" # string offset=115 +.Linfo_string5: + .asciz "test.o" # string offset=124 + .section .debug_str_offsets.dwo,"e",@progbits + .long 0 + .long 7 + .long 10 + .long 14 + .long 115 + .long 124 + .section .debug_info.dwo,"e",@progbits + .long .Ldebug_info_dwo_end0-.Ldebug_info_dwo_start0 # Length of Unit +.Ldebug_info_dwo_start0: + .short 4 # DWARF version number + .long 0 # Offset Into Abbrev. Section + .byte 8 # Address Size (in bytes) + .byte 1 # Abbrev [1] 0xb:0x23 DW_TAG_compile_unit + .byte 3 # DW_AT_producer + .short 33 # DW_AT_language + .byte 4 # DW_AT_name + .byte 5 # DW_AT_GNU_dwo_name + .quad 7198491773836599109 # DW_AT_GNU_dwo_id + .byte 2 # Abbrev [2] 0x19:0x10 DW_TAG_subprogram + .byte 0 # DW_AT_low_pc + .long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc + .byte 1 # DW_AT_frame_base + .byte 87 + # DW_AT_GNU_all_call_sites + .byte 0 # DW_AT_linkage_name + .byte 1 # DW_AT_name + .byte 1 # DW_AT_decl_file + .byte 1 # DW_AT_decl_line + .long 41 # DW_AT_type + # DW_AT_external + .byte 3 # Abbrev [3] 0x29:0x4 DW_TAG_base_type + .byte 2 # DW_AT_name + .byte 5 # DW_AT_encoding + .byte 4 # DW_AT_byte_size + .byte 0 # End Of Children Mark +.Ldebug_info_dwo_end0: + .section .debug_abbrev.dwo,"e",@progbits + .byte 1 # Abbreviation Code + .byte 17 # DW_TAG_compile_unit + .byte 1 # DW_CHILDREN_yes + .byte 37 # DW_AT_producer + .ascii "\202>" # DW_FORM_GNU_str_index + .byte 19 # DW_AT_language + .byte 5 # DW_FORM_data2 + .byte 3 # DW_AT_name + .ascii "\202>" # DW_FORM_GNU_str_index + .ascii "\260B" # DW_AT_GNU_dwo_name + .ascii "\202>" # DW_FORM_GNU_str_index + .ascii "\261B" # DW_AT_GNU_dwo_id + .byte 7 # DW_FORM_data8 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 2 # Abbreviation Code + .byte 46 # DW_TAG_subprogram + .byte 0 # DW_CHILDREN_no + .byte 17 # DW_AT_low_pc + .ascii "\201>" # DW_FORM_GNU_addr_index + .byte 18 # DW_AT_high_pc + .byte 6 # DW_FORM_data4 + .byte 64 # DW_AT_frame_base + .byte 24 # DW_FORM_exprloc + .ascii "\227B" # DW_AT_GNU_all_call_sites + .byte 25 # DW_FORM_flag_present + .byte 110 # DW_AT_linkage_name + .ascii "\202>" # DW_FORM_GNU_str_index + .byte 3 # DW_AT_name + .ascii "\202>" # DW_FORM_GNU_str_index + .byte 58 # DW_AT_decl_file + .byte 11 # DW_FORM_data1 + .byte 59 # DW_AT_decl_line + .byte 11 # DW_FORM_data1 + .byte 73 # DW_AT_type + .byte 19 # DW_FORM_ref4 + .byte 63 # DW_AT_external + .byte 25 # DW_FORM_flag_present + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 3 # Abbreviation Code + .byte 36 # DW_TAG_base_type + .byte 0 # DW_CHILDREN_no + .byte 3 # DW_AT_name + .ascii "\202>" # DW_FORM_GNU_str_index + .byte 62 # DW_AT_encoding + .byte 11 # DW_FORM_data1 + .byte 11 # DW_AT_byte_size + .byte 11 # DW_FORM_data1 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 0 # EOM(3) + .section .debug_addr,"",@progbits +.Laddr_table_base0: + .quad .Lfunc_begin0 + .section .debug_gnu_pubnames,"",@progbits + .long .LpubNames_end0-.LpubNames_start0 # Length of Public Names Info +.LpubNames_start0: + .short 2 # DWARF Version + .long .Lcu_begin0 # Offset of Compilation Unit Info + .long 48 # Compilation Unit Length + .long 25 # DIE offset + .byte 48 # Attributes: FUNCTION, EXTERNAL + .asciz "f1" # External Name + .long 0 # End Mark +.LpubNames_end0: + .section .debug_gnu_pubtypes,"",@progbits + .long .LpubTypes_end0-.LpubTypes_start0 # Length of Public Types Info +.LpubTypes_start0: + .short 2 # DWARF Version + .long .Lcu_begin0 # Offset of Compilation Unit Info + .long 48 # Compilation Unit Length + .long 41 # DIE offset + .byte 144 # Attributes: TYPE, STATIC + .asciz "int" # External Name + .long 0 # End Mark +.LpubTypes_end0: + .ident "clang version 13.0.0 (git@github.com:llvm/llvm-project.git 882ee7fbd6fc989fba53f3d9672440771feb80f5)" + .section ".note.GNU-stack","",@progbits + .addrsig + .section .debug_line,"",@progbits +.Lline_table_start0: