From eb46def978a60fd705cca3037feff5573122b404 Mon Sep 17 00:00:00 2001 From: Richard Mitton Date: Mon, 23 Sep 2013 17:56:20 +0000 Subject: [PATCH] Fixed debug_aranges handling for common symbols. The size of common symbols is now tracked correctly, so they can be listed in the arange section without needing knowledge of other following symbols. .comm (and .lcomm) do not indicate to the system assembler any particular section to use, so we have to treat them as having no section. Test case update to account for this. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191210 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/AsmPrinter/AsmPrinter.cpp | 3 +++ lib/CodeGen/AsmPrinter/DwarfDebug.cpp | 15 ++++++++++----- lib/CodeGen/AsmPrinter/DwarfDebug.h | 7 +++++++ lib/MC/MCAsmStreamer.cpp | 8 ++++---- test/DebugInfo/X86/dwarf-aranges.ll | 11 ++++++----- 5 files changed, 30 insertions(+), 14 deletions(-) diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp index e66237706bc..de08b77012b 100644 --- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp +++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp @@ -292,6 +292,9 @@ void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) { // sections and expected to be contiguous (e.g. ObjC metadata). unsigned AlignLog = getGVAlignmentLog2(GV, *TD); + if (DD) + DD->setSymbolSize(GVSym, Size); + // Handle common and BSS local symbols (.lcomm). if (GVKind.isCommon() || GVKind.isBSSLocal()) { if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index 6414969774b..48a7c185ec2 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -2838,12 +2838,17 @@ void DwarfDebug::emitDebugARanges() { Asm->EmitLabelReference(Span.Start, PtrSize); // Calculate the size as being from the span start to it's end. - // If we have no valid end symbol, then we just cover the first byte. - // (this sucks, but I can't seem to figure out how to get the size) - if (Span.End) + if (Span.End) { Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); - else - Asm->OutStreamer.EmitIntValue(1, PtrSize); + } else { + // For symbols without an end marker (e.g. common), we + // write a single arange entry containing just that one symbol. + uint64_t Size = SymSize[Span.Start]; + if (Size == 0) + Size = 1; + + Asm->OutStreamer.EmitIntValue(Size, PtrSize); + } } Asm->OutStreamer.AddComment("ARange terminator"); diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h index 8fe60c77be5..e774c653945 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.h +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h @@ -341,6 +341,9 @@ class DwarfDebug { // List of all labels used in the output. std::vector Labels; + // Size of each symbol emitted (for those symbols that have a specific size). + DenseMap SymSize; + // Provides a unique id per text section. typedef DenseMap > SectionMapType; SectionMapType SectionMap; @@ -682,6 +685,10 @@ public: /// \brief Add a label so that arange data can be generated for it. void addLabel(SymbolCU SCU) { Labels.push_back(SCU); } + /// \brief For symbols that have a size designated (e.g. common symbols), + /// this tracks that size. + void setSymbolSize(const MCSymbol *Sym, uint64_t Size) { SymSize[Sym] = Size;} + /// \brief Look up the source id with the given directory and source file /// names. If none currently exists, create a new id and insert it in the /// SourceIds map. diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp index e57025e1019..80b0acec846 100644 --- a/lib/MC/MCAsmStreamer.cpp +++ b/lib/MC/MCAsmStreamer.cpp @@ -533,8 +533,8 @@ void MCAsmStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) { void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlignment) { - const MCSection *Section = getContext().getObjectFileInfo()->getBSSSection(); - AssignSection(Symbol, Section); + // Common symbols do not belong to any actual section. + AssignSection(Symbol, NULL); OS << "\t.comm\t" << *Symbol << ',' << Size; if (ByteAlignment != 0) { @@ -552,8 +552,8 @@ void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, /// @param Size - The size of the common symbol. void MCAsmStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size, unsigned ByteAlign) { - const MCSection *Section = getContext().getObjectFileInfo()->getBSSSection(); - AssignSection(Symbol, Section); + // Common symbols do not belong to any actual section. + AssignSection(Symbol, NULL); OS << "\t.lcomm\t" << *Symbol << ',' << Size; if (ByteAlign > 1) { diff --git a/test/DebugInfo/X86/dwarf-aranges.ll b/test/DebugInfo/X86/dwarf-aranges.ll index eae5c790d82..a2f0059ed25 100644 --- a/test/DebugInfo/X86/dwarf-aranges.ll +++ b/test/DebugInfo/X86/dwarf-aranges.ll @@ -18,27 +18,28 @@ ; -- finish -- ; CHECK-HEADER: # ARange terminator - +; - it should have made one span covering all functions in this CU. ; CHECK-CODE: .short 2 # DWARF Arange version number ; CHECK-CODE: .quad .Lfunc_begin0 +; CHECK-CODE-NEXT: .Lset1 = .L.text_end-.Lfunc_begin0 ; CHECK-CODE: # ARange terminator +; - it should have made one span covering all vars in this CU. ; CHECK-DATA: .short 2 # DWARF Arange version number ; CHECK-DATA: .quad some_data ; CHECK-DATA-NEXT: -some_data -; CHECK-DATA-NEXT: .quad ; CHECK-DATA: # ARange terminator +; - it should have made one span for each symbol. ; CHECK-BSS: .short 2 # DWARF Arange version number ; CHECK-BSS: .quad some_bss -; CHECK-BSS-NEXT: -some_bss -; CHECK-BSS-NEXT: .quad +; CHECK-BSS-NEXT: .quad 4 ; CHECK-BSS: # ARange terminator +; - it should have made one span covering all vars in this CU. ; CHECK-CUSTOM: .short 2 # DWARF Arange version number ; CHECK-CUSTOM: .quad some_other ; CHECK-CUSTOM-NEXT: -some_other -; CHECK-CUSTOM-NEXT: .quad ; CHECK-CUSTOM: # ARange terminator -- 2.11.0