From: David Blaikie Date: Tue, 25 Mar 2014 01:44:02 +0000 (+0000) Subject: DebugInfo: Support debug_loc under fission X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=b13d54f5880b2dafadd89182ee9adaff11fa9cf3;p=oota-llvm.git DebugInfo: Support debug_loc under fission Implement debug_loc.dwo, as well as llvm-dwarfdump support for dumping this section. Outlined in the DWARF5 spec and http://gcc.gnu.org/wiki/DebugFission the debug_loc.dwo section has more variation than the standard debug_loc, allowing 3 different forms of entry (plus the end of list entry). GCC seems to, and Clang certainly, only use one form, so I've just implemented dumping support for that for now. It wasn't immediately obvious that there was a good refactoring to share the implementation of dumping support between debug_loc and debug_loc.dwo, so they're separate for now - ideas welcome or I may come back to it at some point. As per a comment in the code, we could choose different forms that may reduce the number of debug_addr entries we emit, but that will require further study. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204697 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/DebugInfo/DIContext.h b/include/llvm/DebugInfo/DIContext.h index f04dc001f4b..69a4f8d1f6b 100644 --- a/include/llvm/DebugInfo/DIContext.h +++ b/include/llvm/DebugInfo/DIContext.h @@ -109,6 +109,7 @@ enum DIDumpType { DIDT_Line, DIDT_LineDwo, DIDT_Loc, + DIDT_LocDwo, DIDT_Ranges, DIDT_Pubnames, DIDT_Pubtypes, diff --git a/include/llvm/Support/Dwarf.h b/include/llvm/Support/Dwarf.h index 7d434dcb12d..87696990600 100644 --- a/include/llvm/Support/Dwarf.h +++ b/include/llvm/Support/Dwarf.h @@ -771,6 +771,14 @@ enum Constants { DW_EH_PE_indirect = 0x80 }; +enum LocationListEntry : unsigned char { + DW_LLE_end_of_list_entry, + DW_LLE_base_address_selection_entry, + DW_LLE_start_end_entry, + DW_LLE_start_length_entry, + DW_LLE_offset_pair_entry +}; + enum ApplePropertyAttributes { // Apple Objective-C Property Attributes DW_APPLE_PROPERTY_readonly = 0x01, diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp index eb3a622ae7f..34f070e0edb 100644 --- a/lib/CodeGen/AsmPrinter/DIE.cpp +++ b/lib/CodeGen/AsmPrinter/DIE.cpp @@ -559,13 +559,15 @@ unsigned DIELocList::SizeOf(AsmPrinter *AP, dwarf::Form Form) const { /// EmitValue - Emit label value. /// void DIELocList::EmitValue(AsmPrinter *AP, dwarf::Form Form) const { + DwarfDebug *DD = AP->getDwarfDebug(); MCSymbol *Label = AP->GetTempSymbol("debug_loc", Index); - MCSymbol *DwarfDebugLocSectionSym = AP->getDwarfDebug()->getDebugLocSym(); - if (AP->MAI->doesDwarfUseRelocationsAcrossSections()) - AP->EmitSectionOffset(Label, DwarfDebugLocSectionSym); + if (DD->useSplitDwarf()) + AP->EmitLabelDifference(Label, DD->getDebugLocDWOSym(), 4); + else if (AP->MAI->doesDwarfUseRelocationsAcrossSections()) + AP->EmitSectionOffset(Label, DD->getDebugLocSym()); else - AP->EmitLabelDifference(Label, DwarfDebugLocSectionSym, 4); + AP->EmitLabelDifference(Label, DD->getDebugLocSym(), 4); } #ifndef NDEBUG diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index 792a9c48cdf..a9ed9dbcb5b 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -184,7 +184,7 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = 0; DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0; - DwarfAddrSectionSym = 0; + DwarfAddrSectionSym = DwarfDebugLocDWOSectionSym = 0; DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0; FunctionBeginSym = FunctionEndSym = 0; CurFn = 0; @@ -1865,7 +1865,6 @@ void DwarfDebug::emitSectionLabels() { DwarfLineSectionSym = emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); - emitSectionSym(Asm, TLOF.getDwarfLocSection()); if (GenerateGnuPubSections) { DwarfGnuPubNamesSectionSym = emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); @@ -1883,12 +1882,13 @@ void DwarfDebug::emitSectionLabels() { emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); DwarfAddrSectionSym = emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); - } + DwarfDebugLocDWOSectionSym = + emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc"); + } else + DwarfDebugLocSectionSym = + emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc"); DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range"); - - DwarfDebugLocSectionSym = - emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc"); } // Recursively emits a debug information entry. @@ -2379,7 +2379,8 @@ void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer, void DwarfDebug::emitDebugLoc() { // Start the dwarf loc section. Asm->OutStreamer.SwitchSection( - Asm->getObjFileLowering().getDwarfLocSection()); + useSplitDwarf() ? Asm->getObjFileLowering().getDwarfLocDWOSection() + : Asm->getObjFileLowering().getDwarfLocSection()); unsigned char Size = Asm->getDataLayout().getPointerSize(); unsigned index = 0; for (const auto &DebugLoc : DotDebugLocEntries) { @@ -2389,7 +2390,16 @@ void DwarfDebug::emitDebugLoc() { // compile unit. This is a hard coded 0 for low_pc when we're emitting // ranges, or the DW_AT_low_pc on the compile unit otherwise. const DwarfCompileUnit *CU = Entry.getCU(); - if (CU->getRanges().size() == 1) { + if (useSplitDwarf()) { + // Just always use start_length for now - at least that's one address + // rather than two. We could get fancier and try to, say, reuse an + // address we know we've emitted elsewhere (the start of the function? + // The start of the CU or CU subrange that encloses this range?) + Asm->EmitInt8(dwarf::DW_LLE_start_length_entry); + unsigned idx = InfoHolder.getAddrPoolIndex(Entry.getBeginSym()); + Asm->EmitULEB128(idx); + Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4); + } else if (CU->getRanges().size() == 1) { // Grab the begin symbol from the first range as our base. const MCSymbol *Base = CU->getRanges()[0].getStart(); Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size); @@ -2409,8 +2419,12 @@ void DwarfDebug::emitDebugLoc() { // Close the range. Asm->OutStreamer.EmitLabel(end); } - Asm->OutStreamer.EmitIntValue(0, Size); - Asm->OutStreamer.EmitIntValue(0, Size); + if (useSplitDwarf()) + Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry); + else { + Asm->OutStreamer.EmitIntValue(0, Size); + Asm->OutStreamer.EmitIntValue(0, Size); + } ++index; } } diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h index 064c0fa7624..0b0f0a8b7aa 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.h +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h @@ -423,7 +423,7 @@ class DwarfDebug : public AsmPrinterHandler { MCSymbol *DwarfDebugLocSectionSym, *DwarfLineSectionSym, *DwarfAddrSectionSym; MCSymbol *FunctionBeginSym, *FunctionEndSym; MCSymbol *DwarfInfoDWOSectionSym, *DwarfAbbrevDWOSectionSym; - MCSymbol *DwarfStrDWOSectionSym; + MCSymbol *DwarfStrDWOSectionSym, *DwarfDebugLocDWOSectionSym; MCSymbol *DwarfGnuPubNamesSectionSym, *DwarfGnuPubTypesSectionSym; // As an optimization, there is no need to emit an entry in the directory @@ -756,6 +756,9 @@ public: /// Returns the section symbol for the .debug_loc section. MCSymbol *getDebugLocSym() const { return DwarfDebugLocSectionSym; } + /// Returns the section symbol for the .debug_loc section. + MCSymbol *getDebugLocDWOSym() const { return DwarfDebugLocDWOSectionSym; } + /// Returns the previous section that was emitted into. const MCSection *getPrevSection() const { return PrevSection; } diff --git a/lib/DebugInfo/DWARFContext.cpp b/lib/DebugInfo/DWARFContext.cpp index 0afe6ef6e13..60c5f6ab56d 100644 --- a/lib/DebugInfo/DWARFContext.cpp +++ b/lib/DebugInfo/DWARFContext.cpp @@ -96,6 +96,11 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) { getDebugLoc()->dump(OS); } + if (DumpType == DIDT_All || DumpType == DIDT_LocDwo) { + OS << "\n.debug_loc.dwo contents:\n"; + getDebugLocDWO()->dump(OS); + } + if (DumpType == DIDT_All || DumpType == DIDT_Frames) { OS << "\n.debug_frame contents:\n"; getDebugFrame()->dump(OS); @@ -237,6 +242,16 @@ const DWARFDebugLoc *DWARFContext::getDebugLoc() { return Loc.get(); } +const DWARFDebugLocDWO *DWARFContext::getDebugLocDWO() { + if (LocDWO) + return LocDWO.get(); + + DataExtractor LocData(getLocDWOSection().Data, isLittleEndian(), 0); + LocDWO.reset(new DWARFDebugLocDWO()); + LocDWO->parse(LocData); + return LocDWO.get(); +} + const DWARFDebugAranges *DWARFContext::getDebugAranges() { if (Aranges) return Aranges.get(); @@ -648,6 +663,7 @@ DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj) .Case("debug_gnu_pubtypes", &GnuPubTypesSection) .Case("debug_info.dwo", &InfoDWOSection.Data) .Case("debug_abbrev.dwo", &AbbrevDWOSection) + .Case("debug_loc.dwo", &LocDWOSection.Data) .Case("debug_line.dwo", &LineDWOSection.Data) .Case("debug_str.dwo", &StringDWOSection) .Case("debug_str_offsets.dwo", &StringOffsetDWOSection) diff --git a/lib/DebugInfo/DWARFContext.h b/lib/DebugInfo/DWARFContext.h index a3bae792737..ad6841ae9e3 100644 --- a/lib/DebugInfo/DWARFContext.h +++ b/lib/DebugInfo/DWARFContext.h @@ -42,6 +42,7 @@ class DWARFContext : public DIContext { CUVector DWOCUs; TUVector DWOTUs; std::unique_ptr AbbrevDWO; + std::unique_ptr LocDWO; DWARFContext(DWARFContext &) LLVM_DELETED_FUNCTION; DWARFContext &operator=(DWARFContext &) LLVM_DELETED_FUNCTION; @@ -148,6 +149,9 @@ public: /// Get a pointer to the parsed dwo abbreviations object. const DWARFDebugAbbrev *getDebugAbbrevDWO(); + /// Get a pointer to the parsed DebugLoc object. + const DWARFDebugLocDWO *getDebugLocDWO(); + /// Get a pointer to the parsed DebugAranges object. const DWARFDebugAranges *getDebugAranges(); @@ -173,6 +177,7 @@ public: virtual const TypeSectionMap &getTypesSections() = 0; virtual StringRef getAbbrevSection() = 0; virtual const Section &getLocSection() = 0; + virtual const Section &getLocDWOSection() = 0; virtual StringRef getARangeSection() = 0; virtual StringRef getDebugFrameSection() = 0; virtual const Section &getLineSection() = 0; @@ -216,6 +221,7 @@ class DWARFContextInMemory : public DWARFContext { TypeSectionMap TypesSections; StringRef AbbrevSection; Section LocSection; + Section LocDWOSection; StringRef ARangeSection; StringRef DebugFrameSection; Section LineSection; @@ -246,6 +252,7 @@ public: const TypeSectionMap &getTypesSections() override { return TypesSections; } StringRef getAbbrevSection() override { return AbbrevSection; } const Section &getLocSection() override { return LocSection; } + const Section &getLocDWOSection() override { return LocDWOSection; } StringRef getARangeSection() override { return ARangeSection; } StringRef getDebugFrameSection() override { return DebugFrameSection; } const Section &getLineSection() override { return LineSection; } diff --git a/lib/DebugInfo/DWARFDebugLoc.cpp b/lib/DebugInfo/DWARFDebugLoc.cpp index 5f0ff0240da..e4aa5dcce27 100644 --- a/lib/DebugInfo/DWARFDebugLoc.cpp +++ b/lib/DebugInfo/DWARFDebugLoc.cpp @@ -11,6 +11,7 @@ #include "llvm/Support/Compiler.h" #include "llvm/Support/Format.h" #include "llvm/Support/raw_ostream.h" +#include "llvm/Support/Dwarf.h" using namespace llvm; @@ -74,3 +75,54 @@ void DWARFDebugLoc::parse(DataExtractor data, unsigned AddressSize) { if (data.isValidOffset(Offset)) llvm::errs() << "error: failed to consume entire .debug_loc section\n"; } + +void DWARFDebugLocDWO::parse(DataExtractor data) { + uint32_t Offset = 0; + while (data.isValidOffset(Offset)) { + Locations.resize(Locations.size() + 1); + LocationList &Loc = Locations.back(); + Loc.Offset = Offset; + dwarf::LocationListEntry Kind; + while ((Kind = static_cast( + data.getU8(&Offset))) != dwarf::DW_LLE_end_of_list_entry) { + + if (Kind != dwarf::DW_LLE_start_length_entry) { + llvm::errs() << "error: dumping support for LLE of kind " << (int)Kind + << " not implemented\n"; + return; + } + + Entry E; + + E.Start = data.getULEB128(&Offset); + E.Length = data.getU32(&Offset); + + unsigned Bytes = data.getU16(&Offset); + // A single location description describing the location of the object... + StringRef str = data.getData().substr(Offset, Bytes); + Offset += Bytes; + E.Loc.resize(str.size()); + std::copy(str.begin(), str.end(), E.Loc.begin()); + + Loc.Entries.push_back(std::move(E)); + } + } +} + +void DWARFDebugLocDWO::dump(raw_ostream &OS) const { + for (const LocationList &L : Locations) { + OS << format("0x%8.8x: ", L.Offset); + const unsigned Indent = 12; + for (const Entry &E : L.Entries) { + if (&E != L.Entries.begin()) + OS.indent(Indent); + OS << "Beginning address index: " << E.Start << '\n'; + OS.indent(Indent) << " Length: " << E.Length << '\n'; + OS.indent(Indent) << " Location description: "; + for (unsigned char Loc : E.Loc) + OS << format("%2.2x ", Loc); + OS << "\n\n"; + } + } +} + diff --git a/lib/DebugInfo/DWARFDebugLoc.h b/lib/DebugInfo/DWARFDebugLoc.h index d31aaaa1273..663acbb42f8 100644 --- a/lib/DebugInfo/DWARFDebugLoc.h +++ b/lib/DebugInfo/DWARFDebugLoc.h @@ -55,6 +55,27 @@ public: /// specified address size to interpret the address ranges. void parse(DataExtractor data, unsigned AddressSize); }; + +class DWARFDebugLocDWO { + struct Entry { + uint64_t Start; + uint32_t Length; + SmallVector Loc; + }; + + struct LocationList { + unsigned Offset; + SmallVector Entries; + }; + + typedef SmallVector LocationLists; + + LocationLists Locations; + +public: + void parse(DataExtractor data); + void dump(raw_ostream &OS) const; +}; } #endif diff --git a/test/DebugInfo/X86/fission-ranges.ll b/test/DebugInfo/X86/fission-ranges.ll index b95038bacc1..a48896f5a55 100644 --- a/test/DebugInfo/X86/fission-ranges.ll +++ b/test/DebugInfo/X86/fission-ranges.ll @@ -1,14 +1,39 @@ ; RUN: llc -split-dwarf=Enable -O0 %s -mtriple=x86_64-unknown-linux-gnu -filetype=obj -o %t -; RUN: llvm-dwarfdump -debug-dump=info.dwo %t | FileCheck %s -; RUN: llvm-objdump -r %t | FileCheck --check-prefix=RELA %s - +; RUN: llvm-dwarfdump %t | FileCheck %s +; RUN: llvm-objdump -h %t | FileCheck --check-prefix=HDR %s + +; CHECK: .debug_info.dwo contents: +; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[A:0x[0-9a-z]*]]) +; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[E:0x[0-9a-z]*]]) +; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[B:0x[0-9a-z]*]]) +; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[D:0x[0-9a-z]*]]) ; CHECK: DW_AT_ranges [DW_FORM_sec_offset] (0x000000a0) +; CHECK: .debug_loc contents: +; CHECK-NOT: Beginning address offset +; CHECK: .debug_loc.dwo contents: + +; Don't assume these locations are entirely correct - feel free to update them +; if they've changed due to a bugfix, change in register allocation, etc. + +; CHECK: [[A]]: Beginning address index: 2 +; CHECK-NEXT: Length: 199 +; CHECK-NEXT: Location description: 10 00 +; CHECK-NEXT: {{^$}} +; CHECK-NEXT: Beginning address index: 3 +; CHECK-NEXT: Length: 23 +; CHECK-NEXT: Location description: 50 93 04 +; CHECK: [[E]]: Beginning address index: 4 +; CHECK-NEXT: Length: 21 +; CHECK-NEXT: Location description: 50 93 04 +; CHECK: [[B]]: Beginning address index: 5 +; CHECK-NEXT: Length: 19 +; CHECK-NEXT: Location description: 50 93 04 +; CHECK: [[D]]: Beginning address index: 6 +; CHECK-NEXT: Length: 23 +; CHECK-NEXT: Location description: 50 93 04 ; Make sure we don't produce any relocations in any .dwo section (though in particular, debug_info.dwo) -; FIXME: There should be no relocations in .dwo sections at all, but for now there are debug_loc relocs here. -; RELA: RELOCATION RECORDS FOR [.rela.debug_info.dwo] -; RELA-NOT: R_X86_64_32 .debug_ranges -; RELA: RELOCATION RECORDS FOR +; HDR-NOT: .rela.{{.*}}.dwo ; From the code: diff --git a/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/tools/llvm-dwarfdump/llvm-dwarfdump.cpp index f019e9e9a98..f4a9ae8bef0 100644 --- a/tools/llvm-dwarfdump/llvm-dwarfdump.cpp +++ b/tools/llvm-dwarfdump/llvm-dwarfdump.cpp @@ -66,6 +66,7 @@ DumpType("debug-dump", cl::init(DIDT_All), clEnumValN(DIDT_Line, "line", ".debug_line"), clEnumValN(DIDT_LineDwo, "line.dwo", ".debug_line.dwo"), clEnumValN(DIDT_Loc, "loc", ".debug_loc"), + clEnumValN(DIDT_LocDwo, "loc.dwo", ".debug_loc.dwo"), clEnumValN(DIDT_Frames, "frames", ".debug_frame"), clEnumValN(DIDT_Ranges, "ranges", ".debug_ranges"), clEnumValN(DIDT_Pubnames, "pubnames", ".debug_pubnames"),