| //===-- SourcePrinter.cpp - source interleaving utilities ----------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the LiveVariablePrinter and SourcePrinter classes to |
| // keep track of DWARF info as the current address is updated, and print out the |
| // source file line and variable liveness as needed. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "SourcePrinter.h" |
| #include "llvm-objdump.h" |
| #include "llvm/ADT/SmallSet.h" |
| #include "llvm/ADT/StringSet.h" |
| #include "llvm/DebugInfo/DWARF/DWARFExpression.h" |
| #include "llvm/DebugInfo/Symbolize/SymbolizableModule.h" |
| #include "llvm/MC/MCSubtargetInfo.h" |
| #include "llvm/Support/FormatVariadic.h" |
| |
| #define DEBUG_TYPE "objdump" |
| |
| namespace llvm { |
| namespace objdump { |
| |
| bool LiveVariable::liveAtAddress(object::SectionedAddress Addr) { |
| if (LocExpr.Range == std::nullopt) |
| return false; |
| return LocExpr.Range->SectionIndex == Addr.SectionIndex && |
| LocExpr.Range->LowPC <= Addr.Address && |
| LocExpr.Range->HighPC > Addr.Address; |
| } |
| |
| void LiveVariable::print(raw_ostream &OS, const MCRegisterInfo &MRI) const { |
| DataExtractor Data({LocExpr.Expr.data(), LocExpr.Expr.size()}, |
| Unit->getContext().isLittleEndian(), 0); |
| DWARFExpression Expression(Data, Unit->getAddressByteSize()); |
| |
| auto GetRegName = [&MRI, &OS](uint64_t DwarfRegNum, bool IsEH) -> StringRef { |
| if (std::optional<unsigned> LLVMRegNum = |
| MRI.getLLVMRegNum(DwarfRegNum, IsEH)) |
| if (const char *RegName = MRI.getName(*LLVMRegNum)) |
| return StringRef(RegName); |
| OS << "<unknown register " << DwarfRegNum << ">"; |
| return {}; |
| }; |
| |
| Expression.printCompact(OS, GetRegName); |
| } |
| |
| void LiveVariablePrinter::addVariable(DWARFDie FuncDie, DWARFDie VarDie) { |
| uint64_t FuncLowPC, FuncHighPC, SectionIndex; |
| FuncDie.getLowAndHighPC(FuncLowPC, FuncHighPC, SectionIndex); |
| const char *VarName = VarDie.getName(DINameKind::ShortName); |
| DWARFUnit *U = VarDie.getDwarfUnit(); |
| |
| Expected<DWARFLocationExpressionsVector> Locs = |
| VarDie.getLocations(dwarf::DW_AT_location); |
| if (!Locs) { |
| // If the variable doesn't have any locations, just ignore it. We don't |
| // report an error or warning here as that could be noisy on optimised |
| // code. |
| consumeError(Locs.takeError()); |
| return; |
| } |
| |
| for (const DWARFLocationExpression &LocExpr : *Locs) { |
| if (LocExpr.Range) { |
| LiveVariables.emplace_back(LocExpr, VarName, U, FuncDie); |
| } else { |
| // If the LocExpr does not have an associated range, it is valid for |
| // the whole of the function. |
| // TODO: technically it is not valid for any range covered by another |
| // LocExpr, does that happen in reality? |
| DWARFLocationExpression WholeFuncExpr{ |
| DWARFAddressRange(FuncLowPC, FuncHighPC, SectionIndex), LocExpr.Expr}; |
| LiveVariables.emplace_back(WholeFuncExpr, VarName, U, FuncDie); |
| } |
| } |
| } |
| |
| void LiveVariablePrinter::addFunction(DWARFDie D) { |
| for (const DWARFDie &Child : D.children()) { |
| if (Child.getTag() == dwarf::DW_TAG_variable || |
| Child.getTag() == dwarf::DW_TAG_formal_parameter) |
| addVariable(D, Child); |
| else |
| addFunction(Child); |
| } |
| } |
| |
| // Get the column number (in characters) at which the first live variable |
| // line should be printed. |
| unsigned LiveVariablePrinter::getIndentLevel() const { |
| return DbgIndent + getInstStartColumn(STI); |
| } |
| |
| // Indent to the first live-range column to the right of the currently |
| // printed line, and return the index of that column. |
| // TODO: formatted_raw_ostream uses "column" to mean a number of characters |
| // since the last \n, and we use it to mean the number of slots in which we |
| // put live variable lines. Pick a less overloaded word. |
| unsigned LiveVariablePrinter::moveToFirstVarColumn(formatted_raw_ostream &OS) { |
| // Logical column number: column zero is the first column we print in, each |
| // logical column is 2 physical columns wide. |
| unsigned FirstUnprintedLogicalColumn = |
| std::max((int)(OS.getColumn() - getIndentLevel() + 1) / 2, 0); |
| // Physical column number: the actual column number in characters, with |
| // zero being the left-most side of the screen. |
| unsigned FirstUnprintedPhysicalColumn = |
| getIndentLevel() + FirstUnprintedLogicalColumn * 2; |
| |
| if (FirstUnprintedPhysicalColumn > OS.getColumn()) |
| OS.PadToColumn(FirstUnprintedPhysicalColumn); |
| |
| return FirstUnprintedLogicalColumn; |
| } |
| |
| unsigned LiveVariablePrinter::findFreeColumn() { |
| for (unsigned ColIdx = 0; ColIdx < ActiveCols.size(); ++ColIdx) |
| if (!ActiveCols[ColIdx].isActive()) |
| return ColIdx; |
| |
| size_t OldSize = ActiveCols.size(); |
| ActiveCols.grow(std::max<size_t>(OldSize * 2, 1)); |
| return OldSize; |
| } |
| |
| void LiveVariablePrinter::dump() const { |
| for (const LiveVariable &LV : LiveVariables) { |
| dbgs() << LV.VarName << " @ " << LV.LocExpr.Range << ": "; |
| LV.print(dbgs(), MRI); |
| dbgs() << "\n"; |
| } |
| } |
| |
| void LiveVariablePrinter::addCompileUnit(DWARFDie D) { |
| if (D.getTag() == dwarf::DW_TAG_subprogram) |
| addFunction(D); |
| else |
| for (const DWARFDie &Child : D.children()) |
| addFunction(Child); |
| } |
| |
| /// Update to match the state of the instruction between ThisAddr and |
| /// NextAddr. In the common case, any live range active at ThisAddr is |
| /// live-in to the instruction, and any live range active at NextAddr is |
| /// live-out of the instruction. If IncludeDefinedVars is false, then live |
| /// ranges starting at NextAddr will be ignored. |
| void LiveVariablePrinter::update(object::SectionedAddress ThisAddr, |
| object::SectionedAddress NextAddr, |
| bool IncludeDefinedVars) { |
| // First, check variables which have already been assigned a column, so |
| // that we don't change their order. |
| SmallSet<unsigned, 8> CheckedVarIdxs; |
| for (unsigned ColIdx = 0, End = ActiveCols.size(); ColIdx < End; ++ColIdx) { |
| if (!ActiveCols[ColIdx].isActive()) |
| continue; |
| CheckedVarIdxs.insert(ActiveCols[ColIdx].VarIdx); |
| LiveVariable &LV = LiveVariables[ActiveCols[ColIdx].VarIdx]; |
| ActiveCols[ColIdx].LiveIn = LV.liveAtAddress(ThisAddr); |
| ActiveCols[ColIdx].LiveOut = LV.liveAtAddress(NextAddr); |
| LLVM_DEBUG(dbgs() << "pass 1, " << ThisAddr.Address << "-" |
| << NextAddr.Address << ", " << LV.VarName << ", Col " |
| << ColIdx << ": LiveIn=" << ActiveCols[ColIdx].LiveIn |
| << ", LiveOut=" << ActiveCols[ColIdx].LiveOut << "\n"); |
| |
| if (!ActiveCols[ColIdx].LiveIn && !ActiveCols[ColIdx].LiveOut) |
| ActiveCols[ColIdx].VarIdx = Column::NullVarIdx; |
| } |
| |
| // Next, look for variables which don't already have a column, but which |
| // are now live. |
| if (IncludeDefinedVars) { |
| for (unsigned VarIdx = 0, End = LiveVariables.size(); VarIdx < End; |
| ++VarIdx) { |
| if (CheckedVarIdxs.count(VarIdx)) |
| continue; |
| LiveVariable &LV = LiveVariables[VarIdx]; |
| bool LiveIn = LV.liveAtAddress(ThisAddr); |
| bool LiveOut = LV.liveAtAddress(NextAddr); |
| if (!LiveIn && !LiveOut) |
| continue; |
| |
| unsigned ColIdx = findFreeColumn(); |
| LLVM_DEBUG(dbgs() << "pass 2, " << ThisAddr.Address << "-" |
| << NextAddr.Address << ", " << LV.VarName << ", Col " |
| << ColIdx << ": LiveIn=" << LiveIn |
| << ", LiveOut=" << LiveOut << "\n"); |
| ActiveCols[ColIdx].VarIdx = VarIdx; |
| ActiveCols[ColIdx].LiveIn = LiveIn; |
| ActiveCols[ColIdx].LiveOut = LiveOut; |
| ActiveCols[ColIdx].MustDrawLabel = true; |
| } |
| } |
| } |
| |
| enum class LineChar { |
| RangeStart, |
| RangeMid, |
| RangeEnd, |
| LabelVert, |
| LabelCornerNew, |
| LabelCornerActive, |
| LabelHoriz, |
| }; |
| const char *LiveVariablePrinter::getLineChar(LineChar C) const { |
| bool IsASCII = DbgVariables == DVASCII; |
| switch (C) { |
| case LineChar::RangeStart: |
| return IsASCII ? "^" : (const char *)u8"\u2548"; |
| case LineChar::RangeMid: |
| return IsASCII ? "|" : (const char *)u8"\u2503"; |
| case LineChar::RangeEnd: |
| return IsASCII ? "v" : (const char *)u8"\u253b"; |
| case LineChar::LabelVert: |
| return IsASCII ? "|" : (const char *)u8"\u2502"; |
| case LineChar::LabelCornerNew: |
| return IsASCII ? "/" : (const char *)u8"\u250c"; |
| case LineChar::LabelCornerActive: |
| return IsASCII ? "|" : (const char *)u8"\u2520"; |
| case LineChar::LabelHoriz: |
| return IsASCII ? "-" : (const char *)u8"\u2500"; |
| } |
| llvm_unreachable("Unhandled LineChar enum"); |
| } |
| |
| /// Print live ranges to the right of an existing line. This assumes the |
| /// line is not an instruction, so doesn't start or end any live ranges, so |
| /// we only need to print active ranges or empty columns. If AfterInst is |
| /// true, this is being printed after the last instruction fed to update(), |
| /// otherwise this is being printed before it. |
| void LiveVariablePrinter::printAfterOtherLine(formatted_raw_ostream &OS, |
| bool AfterInst) { |
| if (ActiveCols.size()) { |
| unsigned FirstUnprintedColumn = moveToFirstVarColumn(OS); |
| for (size_t ColIdx = FirstUnprintedColumn, End = ActiveCols.size(); |
| ColIdx < End; ++ColIdx) { |
| if (ActiveCols[ColIdx].isActive()) { |
| if ((AfterInst && ActiveCols[ColIdx].LiveOut) || |
| (!AfterInst && ActiveCols[ColIdx].LiveIn)) |
| OS << getLineChar(LineChar::RangeMid); |
| else if (!AfterInst && ActiveCols[ColIdx].LiveOut) |
| OS << getLineChar(LineChar::LabelVert); |
| else |
| OS << " "; |
| } |
| OS << " "; |
| } |
| } |
| OS << "\n"; |
| } |
| |
| /// Print any live variable range info needed to the right of a |
| /// non-instruction line of disassembly. This is where we print the variable |
| /// names and expressions, with thin line-drawing characters connecting them |
| /// to the live range which starts at the next instruction. If MustPrint is |
| /// true, we have to print at least one line (with the continuation of any |
| /// already-active live ranges) because something has already been printed |
| /// earlier on this line. |
| void LiveVariablePrinter::printBetweenInsts(formatted_raw_ostream &OS, |
| bool MustPrint) { |
| bool PrintedSomething = false; |
| for (unsigned ColIdx = 0, End = ActiveCols.size(); ColIdx < End; ++ColIdx) { |
| if (ActiveCols[ColIdx].isActive() && ActiveCols[ColIdx].MustDrawLabel) { |
| // First we need to print the live range markers for any active |
| // columns to the left of this one. |
| OS.PadToColumn(getIndentLevel()); |
| for (unsigned ColIdx2 = 0; ColIdx2 < ColIdx; ++ColIdx2) { |
| if (ActiveCols[ColIdx2].isActive()) { |
| if (ActiveCols[ColIdx2].MustDrawLabel && !ActiveCols[ColIdx2].LiveIn) |
| OS << getLineChar(LineChar::LabelVert) << " "; |
| else |
| OS << getLineChar(LineChar::RangeMid) << " "; |
| } else |
| OS << " "; |
| } |
| |
| // Then print the variable name and location of the new live range, |
| // with box drawing characters joining it to the live range line. |
| OS << getLineChar(ActiveCols[ColIdx].LiveIn ? LineChar::LabelCornerActive |
| : LineChar::LabelCornerNew) |
| << getLineChar(LineChar::LabelHoriz) << " "; |
| WithColor(OS, raw_ostream::GREEN) |
| << LiveVariables[ActiveCols[ColIdx].VarIdx].VarName; |
| OS << " = "; |
| { |
| WithColor ExprColor(OS, raw_ostream::CYAN); |
| LiveVariables[ActiveCols[ColIdx].VarIdx].print(OS, MRI); |
| } |
| |
| // If there are any columns to the right of the expression we just |
| // printed, then continue their live range lines. |
| unsigned FirstUnprintedColumn = moveToFirstVarColumn(OS); |
| for (unsigned ColIdx2 = FirstUnprintedColumn, End = ActiveCols.size(); |
| ColIdx2 < End; ++ColIdx2) { |
| if (ActiveCols[ColIdx2].isActive() && ActiveCols[ColIdx2].LiveIn) |
| OS << getLineChar(LineChar::RangeMid) << " "; |
| else |
| OS << " "; |
| } |
| |
| OS << "\n"; |
| PrintedSomething = true; |
| } |
| } |
| |
| for (unsigned ColIdx = 0, End = ActiveCols.size(); ColIdx < End; ++ColIdx) |
| if (ActiveCols[ColIdx].isActive()) |
| ActiveCols[ColIdx].MustDrawLabel = false; |
| |
| // If we must print something (because we printed a line/column number), |
| // but don't have any new variables to print, then print a line which |
| // just continues any existing live ranges. |
| if (MustPrint && !PrintedSomething) |
| printAfterOtherLine(OS, false); |
| } |
| |
| /// Print the live variable ranges to the right of a disassembled instruction. |
| void LiveVariablePrinter::printAfterInst(formatted_raw_ostream &OS) { |
| if (!ActiveCols.size()) |
| return; |
| unsigned FirstUnprintedColumn = moveToFirstVarColumn(OS); |
| for (unsigned ColIdx = FirstUnprintedColumn, End = ActiveCols.size(); |
| ColIdx < End; ++ColIdx) { |
| if (!ActiveCols[ColIdx].isActive()) |
| OS << " "; |
| else if (ActiveCols[ColIdx].LiveIn && ActiveCols[ColIdx].LiveOut) |
| OS << getLineChar(LineChar::RangeMid) << " "; |
| else if (ActiveCols[ColIdx].LiveOut) |
| OS << getLineChar(LineChar::RangeStart) << " "; |
| else if (ActiveCols[ColIdx].LiveIn) |
| OS << getLineChar(LineChar::RangeEnd) << " "; |
| else |
| llvm_unreachable("var must be live in or out!"); |
| } |
| } |
| |
| bool SourcePrinter::cacheSource(const DILineInfo &LineInfo) { |
| std::unique_ptr<MemoryBuffer> Buffer; |
| if (LineInfo.Source) { |
| Buffer = MemoryBuffer::getMemBuffer(*LineInfo.Source); |
| } else { |
| auto BufferOrError = MemoryBuffer::getFile(LineInfo.FileName); |
| if (!BufferOrError) { |
| if (MissingSources.insert(LineInfo.FileName).second) |
| reportWarning("failed to find source " + LineInfo.FileName, |
| Obj->getFileName()); |
| return false; |
| } |
| Buffer = std::move(*BufferOrError); |
| } |
| // Chomp the file to get lines |
| const char *BufferStart = Buffer->getBufferStart(), |
| *BufferEnd = Buffer->getBufferEnd(); |
| std::vector<StringRef> &Lines = LineCache[LineInfo.FileName]; |
| const char *Start = BufferStart; |
| for (const char *I = BufferStart; I != BufferEnd; ++I) |
| if (*I == '\n') { |
| Lines.emplace_back(Start, I - Start - (BufferStart < I && I[-1] == '\r')); |
| Start = I + 1; |
| } |
| if (Start < BufferEnd) |
| Lines.emplace_back(Start, BufferEnd - Start); |
| SourceCache[LineInfo.FileName] = std::move(Buffer); |
| return true; |
| } |
| |
| void SourcePrinter::printSourceLine(formatted_raw_ostream &OS, |
| object::SectionedAddress Address, |
| StringRef ObjectFilename, |
| LiveVariablePrinter &LVP, |
| StringRef Delimiter) { |
| if (!Symbolizer) |
| return; |
| |
| DILineInfo LineInfo = DILineInfo(); |
| Expected<DILineInfo> ExpectedLineInfo = |
| Symbolizer->symbolizeCode(*Obj, Address); |
| std::string ErrorMessage; |
| if (ExpectedLineInfo) { |
| LineInfo = *ExpectedLineInfo; |
| } else if (!WarnedInvalidDebugInfo) { |
| WarnedInvalidDebugInfo = true; |
| // TODO Untested. |
| reportWarning("failed to parse debug information: " + |
| toString(ExpectedLineInfo.takeError()), |
| ObjectFilename); |
| } |
| |
| if (!objdump::Prefix.empty() && |
| sys::path::is_absolute_gnu(LineInfo.FileName)) { |
| // FileName has at least one character since is_absolute_gnu is false for |
| // an empty string. |
| assert(!LineInfo.FileName.empty()); |
| if (PrefixStrip > 0) { |
| uint32_t Level = 0; |
| auto StrippedNameStart = LineInfo.FileName.begin(); |
| |
| // Path.h iterator skips extra separators. Therefore it cannot be used |
| // here to keep compatibility with GNU Objdump. |
| for (auto Pos = StrippedNameStart + 1, End = LineInfo.FileName.end(); |
| Pos != End && Level < PrefixStrip; ++Pos) { |
| if (sys::path::is_separator(*Pos)) { |
| StrippedNameStart = Pos; |
| ++Level; |
| } |
| } |
| |
| LineInfo.FileName = |
| std::string(StrippedNameStart, LineInfo.FileName.end()); |
| } |
| |
| SmallString<128> FilePath; |
| sys::path::append(FilePath, Prefix, LineInfo.FileName); |
| |
| LineInfo.FileName = std::string(FilePath); |
| } |
| |
| if (PrintLines) |
| printLines(OS, LineInfo, Delimiter, LVP); |
| if (PrintSource) |
| printSources(OS, LineInfo, ObjectFilename, Delimiter, LVP); |
| OldLineInfo = LineInfo; |
| } |
| |
| void SourcePrinter::printLines(formatted_raw_ostream &OS, |
| const DILineInfo &LineInfo, StringRef Delimiter, |
| LiveVariablePrinter &LVP) { |
| bool PrintFunctionName = LineInfo.FunctionName != DILineInfo::BadString && |
| LineInfo.FunctionName != OldLineInfo.FunctionName; |
| if (PrintFunctionName) { |
| OS << Delimiter << LineInfo.FunctionName; |
| // If demangling is successful, FunctionName will end with "()". Print it |
| // only if demangling did not run or was unsuccessful. |
| if (!StringRef(LineInfo.FunctionName).ends_with("()")) |
| OS << "()"; |
| OS << ":\n"; |
| } |
| if (LineInfo.FileName != DILineInfo::BadString && LineInfo.Line != 0 && |
| (OldLineInfo.Line != LineInfo.Line || |
| OldLineInfo.FileName != LineInfo.FileName || PrintFunctionName)) { |
| OS << Delimiter << LineInfo.FileName << ":" << LineInfo.Line; |
| LVP.printBetweenInsts(OS, true); |
| } |
| } |
| |
| // Get the source line text for LineInfo: |
| // - use LineInfo::LineSource if available; |
| // - use LineCache if LineInfo::Source otherwise. |
| StringRef SourcePrinter::getLine(const DILineInfo &LineInfo, |
| StringRef ObjectFilename) { |
| if (LineInfo.LineSource) |
| return LineInfo.LineSource.value(); |
| |
| if (SourceCache.find(LineInfo.FileName) == SourceCache.end()) |
| if (!cacheSource(LineInfo)) |
| return {}; |
| |
| auto LineBuffer = LineCache.find(LineInfo.FileName); |
| if (LineBuffer == LineCache.end()) |
| return {}; |
| |
| if (LineInfo.Line > LineBuffer->second.size()) { |
| reportWarning( |
| formatv("debug info line number {0} exceeds the number of lines in {1}", |
| LineInfo.Line, LineInfo.FileName), |
| ObjectFilename); |
| return {}; |
| } |
| |
| // Vector begins at 0, line numbers are non-zero |
| return LineBuffer->second[LineInfo.Line - 1]; |
| } |
| |
| void SourcePrinter::printSources(formatted_raw_ostream &OS, |
| const DILineInfo &LineInfo, |
| StringRef ObjectFilename, StringRef Delimiter, |
| LiveVariablePrinter &LVP) { |
| if (LineInfo.FileName == DILineInfo::BadString || LineInfo.Line == 0 || |
| (OldLineInfo.Line == LineInfo.Line && |
| OldLineInfo.FileName == LineInfo.FileName)) |
| return; |
| |
| StringRef Line = getLine(LineInfo, ObjectFilename); |
| if (!Line.empty()) { |
| OS << Delimiter << Line; |
| LVP.printBetweenInsts(OS, true); |
| } |
| } |
| |
| SourcePrinter::SourcePrinter(const object::ObjectFile *Obj, |
| StringRef DefaultArch) |
| : Obj(Obj) { |
| symbolize::LLVMSymbolizer::Options SymbolizerOpts; |
| SymbolizerOpts.PrintFunctions = |
| DILineInfoSpecifier::FunctionNameKind::LinkageName; |
| SymbolizerOpts.Demangle = Demangle; |
| SymbolizerOpts.DefaultArch = std::string(DefaultArch); |
| Symbolizer.reset(new symbolize::LLVMSymbolizer(SymbolizerOpts)); |
| } |
| |
| } // namespace objdump |
| } // namespace llvm |
