From: Ali Tamur Date: Fri, 19 Apr 2019 02:26:56 +0000 (+0000) Subject: [llvm] Prevent duplicate files in debug line header in dwarf 5: another attempt X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0ee1200779f72907ba5da493191a3a6daeee10cd;p=llvm [llvm] Prevent duplicate files in debug line header in dwarf 5: another attempt Another attempt to land the changes in debug line header to prevent duplicate files in Dwarf 5. I rolled back my previous commit because of a mistake in generating the object file in a test. Meanwhile, I addressed some offline comments and changed the implementation; the largest difference is that MCDwarfLineTableHeader does not keep DwarfVersion but gets it as a parameter. I also merged the patch to fix two lld tests that will strt to fail into this patch. Original Commit: https://reviews.llvm.org/D59515 Original Message: Motivation: In previous dwarf versions, file name indexes started from 1, and the primary source file was not explicit. Dwarf 5 standard (6.2.4) prescribes the primary source file to be explicitly given an entry with an index number 0. The current implementation honors the specification by just duplicating the main source file, once with index number 0, and later maybe with another index number. While this is compliant with the letter of the standard, the duplication causes problems for consumers of this information such as lldb. (Some files are duplicated, where only some of them have a line table although all refer to the same file) With this change, dwarf 5 debug line section files always start from 0, and the zeroth entry is not duplicated whenever possible. This requires different handling of dwarf 4 and dwarf 5 during generation (e.g. when a function returns an index zero for a file name, it signals an error in dwarf 4, but not in dwarf 5) However, I think the minor complication is worth it, because it enables all consumers (lldb, gdb, dwarfdump, objdump, and so on) to treat all files in the file name list homogenously. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358732 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h b/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h index 0fc34a8e7e4..1503a923ea4 100644 --- a/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h +++ b/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h @@ -243,6 +243,9 @@ public: bool hasFileAtIndex(uint64_t FileIndex) const; /// Extracts filename by its index in filename table in prologue. + /// In Dwarf 4, the files are 1-indexed and the current compilation file + /// name is not represented in the list. In Dwarf 5, the files are + /// 0-indexed and the primary source file has the index 0. /// Returns true on success. bool getFileNameByIndex(uint64_t FileIndex, const char *CompDir, DILineInfoSpecifier::FileLineInfoKind Kind, @@ -275,6 +278,8 @@ public: SequenceVector Sequences; private: + const llvm::DWARFDebugLine::FileNameEntry & + getFileNameEntry(uint64_t Index) const; uint32_t findRowInSeq(const DWARFDebugLine::Sequence &Seq, object::SectionedAddress Address) const; Optional diff --git a/include/llvm/MC/MCDwarf.h b/include/llvm/MC/MCDwarf.h index 63040cb194e..2a24347075a 100644 --- a/include/llvm/MC/MCDwarf.h +++ b/include/llvm/MC/MCDwarf.h @@ -41,11 +41,14 @@ class raw_ostream; class SMLoc; class SourceMgr; -/// Instances of this class represent the name of the dwarf -/// .file directive and its associated dwarf file number in the MC file, -/// and MCDwarfFile's are created and uniqued by the MCContext class where -/// the file number for each is its index into the vector of DwarfFiles (note -/// index 0 is not used and not a valid dwarf file number). +/// Instances of this class represent the name of the dwarf .file directive and +/// its associated dwarf file number in the MC file. MCDwarfFile's are created +/// and uniqued by the MCContext class. In Dwarf 4 file numbers start from 1; +/// i.e. the entry with file number 1 is the first element in the vector of +/// DwarfFiles and there is no MCDwarfFile with file number 0. In Dwarf 5 file +/// numbers start from 0, with the MCDwarfFile with file number 0 being the +/// primary source file, and file numbers correspond to their index in the +/// vector. struct MCDwarfFile { // The base name of the file without its directory path. std::string Name; @@ -225,6 +228,7 @@ public: Expected tryGetFile(StringRef &Directory, StringRef &FileName, Optional Checksum, Optional Source, + uint16_t DwarfVersion, unsigned FileNumber = 0); std::pair Emit(MCStreamer *MCOS, MCDwarfLineTableParams Params, @@ -245,6 +249,18 @@ public: return MCDwarfFiles.empty() || (HasAllMD5 == HasAnyMD5); } + void setRootFile(StringRef Directory, StringRef FileName, + Optional Checksum, + Optional Source) { + CompilationDir = Directory; + RootFile.Name = FileName; + RootFile.DirIndex = 0; + RootFile.Checksum = Checksum; + RootFile.Source = Source; + trackMD5Usage(Checksum.hasValue()); + HasSource = Source.hasValue(); + } + private: void emitV2FileDirTables(MCStreamer *MCOS) const; void emitV5FileDirTables(MCStreamer *MCOS, Optional &LineStr) const; @@ -252,24 +268,23 @@ private: class MCDwarfDwoLineTable { MCDwarfLineTableHeader Header; + bool HasSplitLineTable = false; public: void maybeSetRootFile(StringRef Directory, StringRef FileName, - Optional Checksum, Optional Source) { + Optional Checksum, + Optional Source) { if (!Header.RootFile.Name.empty()) return; - Header.CompilationDir = Directory; - Header.RootFile.Name = FileName; - Header.RootFile.DirIndex = 0; - Header.RootFile.Checksum = Checksum; - Header.RootFile.Source = Source; - Header.trackMD5Usage(Checksum.hasValue()); - Header.HasSource = Source.hasValue(); + Header.setRootFile(Directory, FileName, Checksum, Source); } unsigned getFile(StringRef Directory, StringRef FileName, - Optional Checksum, Optional Source) { - return cantFail(Header.tryGetFile(Directory, FileName, Checksum, Source)); + Optional Checksum, uint16_t DwarfVersion, + Optional Source) { + HasSplitLineTable = true; + return cantFail(Header.tryGetFile(Directory, FileName, Checksum, Source, + DwarfVersion)); } void Emit(MCStreamer &MCOS, MCDwarfLineTableParams Params, @@ -291,12 +306,13 @@ public: Expected tryGetFile(StringRef &Directory, StringRef &FileName, Optional Checksum, Optional Source, + uint16_t DwarfVersion, unsigned FileNumber = 0); unsigned getFile(StringRef &Directory, StringRef &FileName, Optional Checksum, Optional Source, - unsigned FileNumber = 0) { + uint16_t DwarfVersion, unsigned FileNumber = 0) { return cantFail(tryGetFile(Directory, FileName, Checksum, Source, - FileNumber)); + DwarfVersion, FileNumber)); } void setRootFile(StringRef Directory, StringRef FileName, diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp index eec10282f57..b14eadd2559 100644 --- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp @@ -315,7 +315,9 @@ unsigned DwarfTypeUnit::getOrCreateSourceID(const DIFile *File) { addSectionOffset(getUnitDie(), dwarf::DW_AT_stmt_list, 0); } return SplitLineTable->getFile(File->getDirectory(), File->getFilename(), - getMD5AsBytes(File), File->getSource()); + getMD5AsBytes(File), + Asm->OutContext.getDwarfVersion(), + File->getSource()); } void DwarfUnit::addOpAddress(DIELoc &Die, const MCSymbol *Sym) { @@ -397,7 +399,6 @@ void DwarfUnit::addSourceLine(DIE &Die, unsigned Line, const DIFile *File) { return; unsigned FileID = getOrCreateSourceID(File); - assert(FileID && "Invalid file id"); addUInt(Die, dwarf::DW_AT_decl_file, None, FileID); addUInt(Die, dwarf::DW_AT_decl_line, None, Line); } diff --git a/lib/DebugInfo/DWARF/DWARFDebugLine.cpp b/lib/DebugInfo/DWARF/DWARFDebugLine.cpp index 47df83e6817..84e13adbef6 100644 --- a/lib/DebugInfo/DWARF/DWARFDebugLine.cpp +++ b/lib/DebugInfo/DWARF/DWARFDebugLine.cpp @@ -969,14 +969,29 @@ bool DWARFDebugLine::LineTable::lookupAddressRangeImpl( } bool DWARFDebugLine::LineTable::hasFileAtIndex(uint64_t FileIndex) const { + uint16_t DwarfVersion = Prologue.getVersion(); + assert(DwarfVersion != 0 && "LineTable has no dwarf version information"); + if (DwarfVersion >= 5) + return FileIndex < Prologue.FileNames.size(); return FileIndex != 0 && FileIndex <= Prologue.FileNames.size(); } +const llvm::DWARFDebugLine::FileNameEntry & +DWARFDebugLine::LineTable::getFileNameEntry(uint64_t Index) const { + uint16_t DwarfVersion = Prologue.getVersion(); + assert(DwarfVersion != 0 && "LineTable has no dwarf version information"); + // Unlike previous versions, in Dwarf 5 the file names is 0-indexed. + if (DwarfVersion >= 5) + return Prologue.FileNames[Index]; + else + return Prologue.FileNames[Index - 1]; +} + Optional DWARFDebugLine::LineTable::getSourceByIndex(uint64_t FileIndex, FileLineInfoKind Kind) const { if (Kind == FileLineInfoKind::None || !hasFileAtIndex(FileIndex)) return None; - const FileNameEntry &Entry = Prologue.FileNames[FileIndex - 1]; + const FileNameEntry &Entry = getFileNameEntry(FileIndex); if (Optional source = Entry.Source.getAsCString()) return StringRef(*source); return None; @@ -996,7 +1011,7 @@ bool DWARFDebugLine::LineTable::getFileNameByIndex(uint64_t FileIndex, std::string &Result) const { if (Kind == FileLineInfoKind::None || !hasFileAtIndex(FileIndex)) return false; - const FileNameEntry &Entry = Prologue.FileNames[FileIndex - 1]; + const FileNameEntry &Entry = getFileNameEntry(FileIndex); StringRef FileName = Entry.Name.getAsCString().getValue(); if (Kind != FileLineInfoKind::AbsoluteFilePath || isPathAbsoluteOnWindowsOrPosix(FileName)) { diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp index ef5c4666d92..350502d633d 100644 --- a/lib/MC/MCAsmStreamer.cpp +++ b/lib/MC/MCAsmStreamer.cpp @@ -1190,7 +1190,8 @@ Expected MCAsmStreamer::tryEmitDwarfFileDirective( MCDwarfLineTable &Table = getContext().getMCDwarfLineTable(CUID); unsigned NumFiles = Table.getMCDwarfFiles().size(); Expected FileNoOrErr = - Table.tryGetFile(Directory, Filename, Checksum, Source, FileNo); + Table.tryGetFile(Directory, Filename, Checksum, Source, + getContext().getDwarfVersion(), FileNo); if (!FileNoOrErr) return FileNoOrErr.takeError(); FileNo = FileNoOrErr.get(); diff --git a/lib/MC/MCContext.cpp b/lib/MC/MCContext.cpp index 4d16715c0ae..6ca7d3df19d 100644 --- a/lib/MC/MCContext.cpp +++ b/lib/MC/MCContext.cpp @@ -605,7 +605,8 @@ Expected MCContext::getDwarfFile(StringRef Directory, Optional Source, unsigned CUID) { MCDwarfLineTable &Table = MCDwarfLineTablesCUMap[CUID]; - return Table.tryGetFile(Directory, FileName, Checksum, Source, FileNumber); + return Table.tryGetFile(Directory, FileName, Checksum, Source, DwarfVersion, + FileNumber); } /// isValidDwarfFileNumber - takes a dwarf file number and returns true if it @@ -613,7 +614,7 @@ Expected MCContext::getDwarfFile(StringRef Directory, bool MCContext::isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID) { const MCDwarfLineTable &LineTable = getMCDwarfLineTable(CUID); if (FileNumber == 0) - return getDwarfVersion() >= 5 && LineTable.hasRootFile(); + return getDwarfVersion() >= 5; if (FileNumber >= LineTable.getMCDwarfFiles().size()) return false; diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp index 262c520a06a..e8edf6ba1d4 100644 --- a/lib/MC/MCDwarf.cpp +++ b/lib/MC/MCDwarf.cpp @@ -259,7 +259,7 @@ void MCDwarfLineTable::Emit(MCObjectStreamer *MCOS, void MCDwarfDwoLineTable::Emit(MCStreamer &MCOS, MCDwarfLineTableParams Params, MCSection *Section) const { - if (Header.MCDwarfFiles.empty()) + if (!HasSplitLineTable) return; Optional NoLineStr(None); MCOS.SwitchSection(Section); @@ -538,8 +538,17 @@ Expected MCDwarfLineTable::tryGetFile(StringRef &Directory, StringRef &FileName, Optional Checksum, Optional Source, + uint16_t DwarfVersion, unsigned FileNumber) { - return Header.tryGetFile(Directory, FileName, Checksum, Source, FileNumber); + return Header.tryGetFile(Directory, FileName, Checksum, Source, DwarfVersion, + FileNumber); +} + +bool isRootFile(const MCDwarfFile &RootFile, StringRef &Directory, + StringRef &FileName, Optional Checksum) { + if (RootFile.Name.empty() || RootFile.Name != FileName.data()) + return false; + return RootFile.Checksum == Checksum; } Expected @@ -547,6 +556,7 @@ MCDwarfLineTableHeader::tryGetFile(StringRef &Directory, StringRef &FileName, Optional Checksum, Optional Source, + uint16_t DwarfVersion, unsigned FileNumber) { if (Directory == CompilationDir) Directory = ""; @@ -561,6 +571,8 @@ MCDwarfLineTableHeader::tryGetFile(StringRef &Directory, trackMD5Usage(Checksum.hasValue()); HasSource = (Source != None); } + if (isRootFile(RootFile, Directory, FileName, Checksum) && DwarfVersion >= 5) + return 0; if (FileNumber == 0) { // File numbers start with 1 and/or after any file numbers // allocated by inline-assembler .file directives. diff --git a/test/MC/ARM/dwarf-asm-multiple-sections.s b/test/MC/ARM/dwarf-asm-multiple-sections.s index cff8f000731..f995958d9f8 100644 --- a/test/MC/ARM/dwarf-asm-multiple-sections.s +++ b/test/MC/ARM/dwarf-asm-multiple-sections.s @@ -2,9 +2,9 @@ // RUN: llvm-dwarfdump -v %t | FileCheck -check-prefix DWARF -check-prefix DWARF45 %s // RUN: llvm-dwarfdump --debug-line %t | FileCheck -check-prefix DWARF-DL -check-prefix DWARF-DL-5 -DDWVER=5 -DDWFILE=0 %s // RUN: llvm-objdump -r %t | FileCheck -check-prefix RELOC -check-prefix RELOC5 %s -// RUN: llvm-mc < %s -triple=armv7-linux-gnueabi -filetype=obj -o %t -g -fdebug-compilation-dir=/tmp +// RUN: llvm-mc < %s -triple=armv7-linux-gnueabi -filetype=obj -o %t -g -dwarf-version 4 -fdebug-compilation-dir=/tmp // RUN: llvm-dwarfdump -v %t | FileCheck -check-prefix DWARF -check-prefix DWARF45 %s -// RUN: llvm-dwarfdump --debug-line %t | FileCheck -check-prefix DWARF-DL -DDWVER=4 -DDWFILE=1 %s +// RUN: llvm-dwarfdump --debug-line %t | FileCheck -check-prefix DWARF-DL -check-prefix DWARF-DL-4 -DDWVER=4 -DDWFILE=1 %s // RUN: llvm-objdump -r %t | FileCheck -check-prefix RELOC -check-prefix RELOC4 %s // RUN: llvm-mc < %s -triple=armv7-linux-gnueabi -filetype=obj -o %t -g -dwarf-version 3 -fdebug-compilation-dir=/tmp // RUN: llvm-dwarfdump -v %t | FileCheck -check-prefix DWARF -check-prefix DWARF3 %s @@ -57,10 +57,14 @@ b: // DWARF-DL-5: include_directories[ 0] = "/tmp" // DWARF-DL: file_names[ [[DWFILE]]]: // DWARF-DL: name: "{{(|-)}}" -// DWARF-DL: 0x0000000000000000 17 0 1 0 0 is_stmt -// DWARF-DL-NEXT: 0x0000000000000004 17 0 1 0 0 is_stmt end_sequence -// DWARF-DL-NEXT: 0x0000000000000000 21 0 1 0 0 is_stmt -// DWARF-DL-NEXT: 0x0000000000000004 21 0 1 0 0 is_stmt end_sequence +// DWARF-DL-5: 0x0000000000000000 17 0 0 0 0 is_stmt +// DWARF-DL-5-NEXT: 0x0000000000000004 17 0 0 0 0 is_stmt end_sequence +// DWARF-DL-5-NEXT: 0x0000000000000000 21 0 0 0 0 is_stmt +// DWARF-DL-5-NEXT: 0x0000000000000004 21 0 0 0 0 is_stmt end_sequence +// DWARF-DL-4: 0x0000000000000000 17 0 1 0 0 is_stmt +// DWARF-DL-4-NEXT: 0x0000000000000004 17 0 1 0 0 is_stmt end_sequence +// DWARF-DL-4-NEXT: 0x0000000000000000 21 0 1 0 0 is_stmt +// DWARF-DL-4-NEXT: 0x0000000000000004 21 0 1 0 0 is_stmt end_sequence // DWARF: .debug_ranges contents: diff --git a/test/MC/ELF/debug-mixed-md5.ll b/test/MC/ELF/debug-mixed-md5.ll index 2ec8141325f..d48e42c8d12 100644 --- a/test/MC/ELF/debug-mixed-md5.ll +++ b/test/MC/ELF/debug-mixed-md5.ll @@ -1,8 +1,7 @@ ; RUN: %llc_dwarf -filetype=asm -dwarf-version=5 %s -o - | FileCheck %s -check-prefix=ASM ; RUN: %llc_dwarf -filetype=obj -dwarf-version=5 %s -o - | llvm-dwarfdump -debug-line - | FileCheck %s -check-prefix=OBJ ; ASM: .file 0 "{{.+}}" md5 -; ASM: .file 1 "{{.+}}" md5 -; ASM: .file 2 "t1.cpp" +; ASM: .file 1 "t1.cpp" ; ASM-NOT: md5 ; OBJ: file_names[ 0]: ; OBJ-NOT: md5 diff --git a/test/MC/ELF/dwarf-file0.s b/test/MC/ELF/dwarf-file0.s index 1a3afb6875f..f98fdcc2b40 100644 --- a/test/MC/ELF/dwarf-file0.s +++ b/test/MC/ELF/dwarf-file0.s @@ -19,16 +19,14 @@ # CHECK: file_names[ 1]: # CHECK-NEXT: name: "header.h" # CHECK-NEXT: dir_index: 1 -# CHECK: file_names[ 2]: -# CHECK-NEXT: name: "root.cpp" +# CHECK-4: file_names[ 2]: +# CHECK-4-NEXT: name: "root.cpp" # CHECK-4-NEXT: dir_index: 2 -# CHECK-5-NEXT: dir_index: 0 # ASM-NOT: .file # ASM-5: .file 0 "/test" "root.cpp" # ASM: .file 1 "/include" "header.h" # ASM-4: .file 2 "/test" "root.cpp" -# ASM-5: .file 2 "root.cpp" # ASM-NOT: .file # WARN: file 0 not supported prior to DWARF-5 diff --git a/test/tools/llvm-objdump/Inputs/embedded-source b/test/tools/llvm-objdump/Inputs/embedded-source index 072b5a90c5c..8274a6619ed 100644 Binary files a/test/tools/llvm-objdump/Inputs/embedded-source and b/test/tools/llvm-objdump/Inputs/embedded-source differ diff --git a/test/tools/llvm-objdump/X86/function-sections-line-numbers.s b/test/tools/llvm-objdump/X86/function-sections-line-numbers.s index b932a5d3f32..46607440cb9 100644 --- a/test/tools/llvm-objdump/X86/function-sections-line-numbers.s +++ b/test/tools/llvm-objdump/X86/function-sections-line-numbers.s @@ -30,8 +30,7 @@ _Z2f1v: # @_Z2f1v .Lfunc_begin0: .file 0 "/home/avl" "test.cpp" md5 0xefae234cc05b45384d782316d3a5d338 - .file 1 "test.cpp" md5 0xefae234cc05b45384d782316d3a5d338 - .loc 1 1 0 # test.cpp:1:0 + .loc 0 1 0 # test.cpp:1:0 .cfi_startproc # %bb.0: # %entry pushq %rbp @@ -40,7 +39,7 @@ _Z2f1v: # @_Z2f1v movq %rsp, %rbp .cfi_def_cfa_register %rbp .Ltmp0: - .loc 1 1 12 prologue_end # test.cpp:1:12 + .loc 0 1 12 prologue_end # test.cpp:1:12 popq %rbp .cfi_def_cfa %rsp, 8 retq @@ -55,7 +54,7 @@ _Z2f1v: # @_Z2f1v .type _Z2f2v,@function _Z2f2v: # @_Z2f2v .Lfunc_begin1: - .loc 1 2 0 # test.cpp:2:0 + .loc 0 2 0 # test.cpp:2:0 .cfi_startproc # %bb.0: # %entry pushq %rbp @@ -64,7 +63,7 @@ _Z2f2v: # @_Z2f2v movq %rsp, %rbp .cfi_def_cfa_register %rbp .Ltmp2: - .loc 1 2 12 prologue_end # test.cpp:2:12 + .loc 0 2 12 prologue_end # test.cpp:2:12 popq %rbp .cfi_def_cfa %rsp, 8 retq