1 files changed, 767 insertions, 0 deletions
diff --git a/contrib/llvm/lib/DebugInfo/DWARFContext.cpp b/contrib/llvm/lib/DebugInfo/DWARFContext.cpp
new file mode 100644
index 0000000..3961905
--- /dev/null
+++ b/contrib/llvm/lib/DebugInfo/DWARFContext.cpp
@@ -0,0 +1,767 @@
+//===-- DWARFContext.cpp --------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DWARFContext.h"
+#include "DWARFDebugArangeSet.h"
+
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/Compression.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+using namespace llvm;
+using namespace dwarf;
+using namespace object;
+
+#define DEBUG_TYPE "dwarf"
+
+typedef DWARFDebugLine::LineTable DWARFLineTable;
+typedef DILineInfoSpecifier::FileLineInfoKind FileLineInfoKind;
+typedef DILineInfoSpecifier::FunctionNameKind FunctionNameKind;
+
+static void dumpPubSection(raw_ostream &OS, StringRef Name, StringRef Data,
+                           bool LittleEndian, bool GnuStyle) {
+  OS << "\n." << Name << " contents:\n";
+  DataExtractor pubNames(Data, LittleEndian, 0);
+  uint32_t offset = 0;
+  while (pubNames.isValidOffset(offset)) {
+    OS << "length = " << format("0x%08x", pubNames.getU32(&offset));
+    OS << " version = " << format("0x%04x", pubNames.getU16(&offset));
+    OS << " unit_offset = " << format("0x%08x", pubNames.getU32(&offset));
+    OS << " unit_size = " << format("0x%08x", pubNames.getU32(&offset)) << '\n';
+    if (GnuStyle)
+      OS << "Offset     Linkage  Kind     Name\n";
+    else
+      OS << "Offset     Name\n";
+
+    while (offset < Data.size()) {
+      uint32_t dieRef = pubNames.getU32(&offset);
+      if (dieRef == 0)
+        break;
+      OS << format("0x%8.8x ", dieRef);
+      if (GnuStyle) {
+        PubIndexEntryDescriptor desc(pubNames.getU8(&offset));
+        OS << format("%-8s", dwarf::GDBIndexEntryLinkageString(desc.Linkage))
+           << ' ' << format("%-8s", dwarf::GDBIndexEntryKindString(desc.Kind))
+           << ' ';
+      }
+      OS << '\"' << pubNames.getCStr(&offset) << "\"\n";
+    }
+  }
+}
+
+void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) {
+  if (DumpType == DIDT_All || DumpType == DIDT_Abbrev) {
+    OS << ".debug_abbrev contents:\n";
+    getDebugAbbrev()->dump(OS);
+  }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_AbbrevDwo)
+    if (const DWARFDebugAbbrev *D = getDebugAbbrevDWO()) {
+      OS << "\n.debug_abbrev.dwo contents:\n";
+      D->dump(OS);
+    }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_Info) {
+    OS << "\n.debug_info contents:\n";
+    for (const auto &CU : compile_units())
+      CU->dump(OS);
+  }
+
+  if ((DumpType == DIDT_All || DumpType == DIDT_InfoDwo) &&
+      getNumDWOCompileUnits()) {
+    OS << "\n.debug_info.dwo contents:\n";
+    for (const auto &DWOCU : dwo_compile_units())
+      DWOCU->dump(OS);
+  }
+
+  if ((DumpType == DIDT_All || DumpType == DIDT_Types) && getNumTypeUnits()) {
+    OS << "\n.debug_types contents:\n";
+    for (const auto &TU : type_units())
+      TU->dump(OS);
+  }
+
+  if ((DumpType == DIDT_All || DumpType == DIDT_TypesDwo) &&
+      getNumDWOTypeUnits()) {
+    OS << "\n.debug_types.dwo contents:\n";
+    for (const auto &DWOTU : dwo_type_units())
+      DWOTU->dump(OS);
+  }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_Loc) {
+    OS << "\n.debug_loc contents:\n";
+    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);
+  }
+
+  uint32_t offset = 0;
+  if (DumpType == DIDT_All || DumpType == DIDT_Aranges) {
+    OS << "\n.debug_aranges contents:\n";
+    DataExtractor arangesData(getARangeSection(), isLittleEndian(), 0);
+    DWARFDebugArangeSet set;
+    while (set.extract(arangesData, &offset))
+      set.dump(OS);
+  }
+
+  uint8_t savedAddressByteSize = 0;
+  if (DumpType == DIDT_All || DumpType == DIDT_Line) {
+    OS << "\n.debug_line contents:\n";
+    for (const auto &CU : compile_units()) {
+      savedAddressByteSize = CU->getAddressByteSize();
+      unsigned stmtOffset =
+          CU->getCompileUnitDIE()->getAttributeValueAsSectionOffset(
+              CU.get(), DW_AT_stmt_list, -1U);
+      if (stmtOffset != -1U) {
+        DataExtractor lineData(getLineSection().Data, isLittleEndian(),
+                               savedAddressByteSize);
+        DWARFDebugLine::LineTable LineTable;
+        LineTable.parse(lineData, &getLineSection().Relocs, &stmtOffset);
+        LineTable.dump(OS);
+      }
+    }
+  }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_LineDwo) {
+    OS << "\n.debug_line.dwo contents:\n";
+    unsigned stmtOffset = 0;
+    DataExtractor lineData(getLineDWOSection().Data, isLittleEndian(),
+                           savedAddressByteSize);
+    DWARFDebugLine::LineTable LineTable;
+    while (LineTable.Prologue.parse(lineData, &stmtOffset)) {
+      LineTable.dump(OS);
+      LineTable.clear();
+    }
+  }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_Str) {
+    OS << "\n.debug_str contents:\n";
+    DataExtractor strData(getStringSection(), isLittleEndian(), 0);
+    offset = 0;
+    uint32_t strOffset = 0;
+    while (const char *s = strData.getCStr(&offset)) {
+      OS << format("0x%8.8x: \"%s\"\n", strOffset, s);
+      strOffset = offset;
+    }
+  }
+
+  if ((DumpType == DIDT_All || DumpType == DIDT_StrDwo) &&
+      !getStringDWOSection().empty()) {
+    OS << "\n.debug_str.dwo contents:\n";
+    DataExtractor strDWOData(getStringDWOSection(), isLittleEndian(), 0);
+    offset = 0;
+    uint32_t strDWOOffset = 0;
+    while (const char *s = strDWOData.getCStr(&offset)) {
+      OS << format("0x%8.8x: \"%s\"\n", strDWOOffset, s);
+      strDWOOffset = offset;
+    }
+  }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_Ranges) {
+    OS << "\n.debug_ranges contents:\n";
+    // In fact, different compile units may have different address byte
+    // sizes, but for simplicity we just use the address byte size of the last
+    // compile unit (there is no easy and fast way to associate address range
+    // list and the compile unit it describes).
+    DataExtractor rangesData(getRangeSection(), isLittleEndian(),
+                             savedAddressByteSize);
+    offset = 0;
+    DWARFDebugRangeList rangeList;
+    while (rangeList.extract(rangesData, &offset))
+      rangeList.dump(OS);
+  }
+
+  if (DumpType == DIDT_All || DumpType == DIDT_Pubnames)
+    dumpPubSection(OS, "debug_pubnames", getPubNamesSection(),
+                   isLittleEndian(), false);
+
+  if (DumpType == DIDT_All || DumpType == DIDT_Pubtypes)
+    dumpPubSection(OS, "debug_pubtypes", getPubTypesSection(),
+                   isLittleEndian(), false);
+
+  if (DumpType == DIDT_All || DumpType == DIDT_GnuPubnames)
+    dumpPubSection(OS, "debug_gnu_pubnames", getGnuPubNamesSection(),
+                   isLittleEndian(), true /* GnuStyle */);
+
+  if (DumpType == DIDT_All || DumpType == DIDT_GnuPubtypes)
+    dumpPubSection(OS, "debug_gnu_pubtypes", getGnuPubTypesSection(),
+                   isLittleEndian(), true /* GnuStyle */);
+
+  if ((DumpType == DIDT_All || DumpType == DIDT_StrOffsetsDwo) &&
+      !getStringOffsetDWOSection().empty()) {
+    OS << "\n.debug_str_offsets.dwo contents:\n";
+    DataExtractor strOffsetExt(getStringOffsetDWOSection(), isLittleEndian(),
+                               0);
+    offset = 0;
+    uint64_t size = getStringOffsetDWOSection().size();
+    while (offset < size) {
+      OS << format("0x%8.8x: ", offset);
+      OS << format("%8.8x\n", strOffsetExt.getU32(&offset));
+    }
+  }
+}
+
+const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
+  if (Abbrev)
+    return Abbrev.get();
+
+  DataExtractor abbrData(getAbbrevSection(), isLittleEndian(), 0);
+
+  Abbrev.reset(new DWARFDebugAbbrev());
+  Abbrev->extract(abbrData);
+  return Abbrev.get();
+}
+
+const DWARFDebugAbbrev *DWARFContext::getDebugAbbrevDWO() {
+  if (AbbrevDWO)
+    return AbbrevDWO.get();
+
+  DataExtractor abbrData(getAbbrevDWOSection(), isLittleEndian(), 0);
+  AbbrevDWO.reset(new DWARFDebugAbbrev());
+  AbbrevDWO->extract(abbrData);
+  return AbbrevDWO.get();
+}
+
+const DWARFDebugLoc *DWARFContext::getDebugLoc() {
+  if (Loc)
+    return Loc.get();
+
+  DataExtractor LocData(getLocSection().Data, isLittleEndian(), 0);
+  Loc.reset(new DWARFDebugLoc(getLocSection().Relocs));
+  // assume all compile units have the same address byte size
+  if (getNumCompileUnits())
+    Loc->parse(LocData, getCompileUnitAtIndex(0)->getAddressByteSize());
+  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();
+
+  Aranges.reset(new DWARFDebugAranges());
+  Aranges->generate(this);
+  return Aranges.get();
+}
+
+const DWARFDebugFrame *DWARFContext::getDebugFrame() {
+  if (DebugFrame)
+    return DebugFrame.get();
+
+  // There's a "bug" in the DWARFv3 standard with respect to the target address
+  // size within debug frame sections. While DWARF is supposed to be independent
+  // of its container, FDEs have fields with size being "target address size",
+  // which isn't specified in DWARF in general. It's only specified for CUs, but
+  // .eh_frame can appear without a .debug_info section. Follow the example of
+  // other tools (libdwarf) and extract this from the container (ObjectFile
+  // provides this information). This problem is fixed in DWARFv4
+  // See this dwarf-discuss discussion for more details:
+  // http://lists.dwarfstd.org/htdig.cgi/dwarf-discuss-dwarfstd.org/2011-December/001173.html
+  DataExtractor debugFrameData(getDebugFrameSection(), isLittleEndian(),
+                               getAddressSize());
+  DebugFrame.reset(new DWARFDebugFrame());
+  DebugFrame->parse(debugFrameData);
+  return DebugFrame.get();
+}
+
+const DWARFLineTable *
+DWARFContext::getLineTableForCompileUnit(DWARFCompileUnit *cu) {
+  if (!Line)
+    Line.reset(new DWARFDebugLine(&getLineSection().Relocs));
+
+  unsigned stmtOffset =
+      cu->getCompileUnitDIE()->getAttributeValueAsSectionOffset(
+          cu, DW_AT_stmt_list, -1U);
+  if (stmtOffset == -1U)
+    return nullptr; // No line table for this compile unit.
+
+  // See if the line table is cached.
+  if (const DWARFLineTable *lt = Line->getLineTable(stmtOffset))
+    return lt;
+
+  // We have to parse it first.
+  DataExtractor lineData(getLineSection().Data, isLittleEndian(),
+                         cu->getAddressByteSize());
+  return Line->getOrParseLineTable(lineData, stmtOffset);
+}
+
+void DWARFContext::parseCompileUnits() {
+  if (!CUs.empty())
+    return;
+  uint32_t offset = 0;
+  const DataExtractor &DIData = DataExtractor(getInfoSection().Data,
+                                              isLittleEndian(), 0);
+  while (DIData.isValidOffset(offset)) {
+    std::unique_ptr<DWARFCompileUnit> CU(new DWARFCompileUnit(
+        getDebugAbbrev(), getInfoSection().Data, getRangeSection(),
+        getStringSection(), StringRef(), getAddrSection(),
+        &getInfoSection().Relocs, isLittleEndian()));
+    if (!CU->extract(DIData, &offset)) {
+      break;
+    }
+    CUs.push_back(std::move(CU));
+    offset = CUs.back()->getNextUnitOffset();
+  }
+}
+
+void DWARFContext::parseTypeUnits() {
+  if (!TUs.empty())
+    return;
+  for (const auto &I : getTypesSections()) {
+    uint32_t offset = 0;
+    const DataExtractor &DIData =
+        DataExtractor(I.second.Data, isLittleEndian(), 0);
+    while (DIData.isValidOffset(offset)) {
+      std::unique_ptr<DWARFTypeUnit> TU(
+          new DWARFTypeUnit(getDebugAbbrev(), I.second.Data, getRangeSection(),
+                            getStringSection(), StringRef(), getAddrSection(),
+                            &I.second.Relocs, isLittleEndian()));
+      if (!TU->extract(DIData, &offset))
+        break;
+      TUs.push_back(std::move(TU));
+      offset = TUs.back()->getNextUnitOffset();
+    }
+  }
+}
+
+void DWARFContext::parseDWOCompileUnits() {
+  if (!DWOCUs.empty())
+    return;
+  uint32_t offset = 0;
+  const DataExtractor &DIData =
+      DataExtractor(getInfoDWOSection().Data, isLittleEndian(), 0);
+  while (DIData.isValidOffset(offset)) {
+    std::unique_ptr<DWARFCompileUnit> DWOCU(new DWARFCompileUnit(
+        getDebugAbbrevDWO(), getInfoDWOSection().Data, getRangeDWOSection(),
+        getStringDWOSection(), getStringOffsetDWOSection(), getAddrSection(),
+        &getInfoDWOSection().Relocs, isLittleEndian()));
+    if (!DWOCU->extract(DIData, &offset)) {
+      break;
+    }
+    DWOCUs.push_back(std::move(DWOCU));
+    offset = DWOCUs.back()->getNextUnitOffset();
+  }
+}
+
+void DWARFContext::parseDWOTypeUnits() {
+  if (!DWOTUs.empty())
+    return;
+  for (const auto &I : getTypesDWOSections()) {
+    uint32_t offset = 0;
+    const DataExtractor &DIData =
+        DataExtractor(I.second.Data, isLittleEndian(), 0);
+    while (DIData.isValidOffset(offset)) {
+      std::unique_ptr<DWARFTypeUnit> TU(new DWARFTypeUnit(
+          getDebugAbbrevDWO(), I.second.Data, getRangeDWOSection(),
+          getStringDWOSection(), getStringOffsetDWOSection(), getAddrSection(),
+          &I.second.Relocs, isLittleEndian()));
+      if (!TU->extract(DIData, &offset))
+        break;
+      DWOTUs.push_back(std::move(TU));
+      offset = DWOTUs.back()->getNextUnitOffset();
+    }
+  }
+}
+
+namespace {
+  struct OffsetComparator {
+
+    bool operator()(const std::unique_ptr<DWARFCompileUnit> &LHS,
+                    const std::unique_ptr<DWARFCompileUnit> &RHS) const {
+      return LHS->getOffset() < RHS->getOffset();
+    }
+    bool operator()(const std::unique_ptr<DWARFCompileUnit> &LHS,
+                    uint32_t RHS) const {
+      return LHS->getOffset() < RHS;
+    }
+    bool operator()(uint32_t LHS,
+                    const std::unique_ptr<DWARFCompileUnit> &RHS) const {
+      return LHS < RHS->getOffset();
+    }
+  };
+}
+
+DWARFCompileUnit *DWARFContext::getCompileUnitForOffset(uint32_t Offset) {
+  parseCompileUnits();
+
+  std::unique_ptr<DWARFCompileUnit> *CU =
+      std::lower_bound(CUs.begin(), CUs.end(), Offset, OffsetComparator());
+  if (CU != CUs.end()) {
+    return CU->get();
+  }
+  return nullptr;
+}
+
+DWARFCompileUnit *DWARFContext::getCompileUnitForAddress(uint64_t Address) {
+  // First, get the offset of the compile unit.
+  uint32_t CUOffset = getDebugAranges()->findAddress(Address);
+  // Retrieve the compile unit.
+  return getCompileUnitForOffset(CUOffset);
+}
+
+static bool getFileNameForCompileUnit(DWARFCompileUnit *CU,
+                                      const DWARFLineTable *LineTable,
+                                      uint64_t FileIndex, FileLineInfoKind Kind,
+                                      std::string &FileName) {
+  if (!CU || !LineTable || Kind == FileLineInfoKind::None ||
+      !LineTable->getFileNameByIndex(FileIndex, Kind, FileName))
+    return false;
+  if (Kind == FileLineInfoKind::AbsoluteFilePath &&
+      sys::path::is_relative(FileName)) {
+    // We may still need to append compilation directory of compile unit.
+    SmallString<16> AbsolutePath;
+    if (const char *CompilationDir = CU->getCompilationDir()) {
+      sys::path::append(AbsolutePath, CompilationDir);
+    }
+    sys::path::append(AbsolutePath, FileName);
+    FileName = AbsolutePath.str();
+  }
+  return true;
+}
+
+static bool getFileLineInfoForCompileUnit(DWARFCompileUnit *CU,
+                                          const DWARFLineTable *LineTable,
+                                          uint64_t Address,
+                                          FileLineInfoKind Kind,
+                                          DILineInfo &Result) {
+  if (!CU || !LineTable)
+    return false;
+  // Get the index of row we're looking for in the line table.
+  uint32_t RowIndex = LineTable->lookupAddress(Address);
+  if (RowIndex == -1U)
+    return false;
+  // Take file number and line/column from the row.
+  const DWARFDebugLine::Row &Row = LineTable->Rows[RowIndex];
+  if (!getFileNameForCompileUnit(CU, LineTable, Row.File, Kind,
+                                 Result.FileName))
+    return false;
+  Result.Line = Row.Line;
+  Result.Column = Row.Column;
+  return true;
+}
+
+static bool getFunctionNameForAddress(DWARFCompileUnit *CU, uint64_t Address,
+                                      FunctionNameKind Kind,
+                                      std::string &FunctionName) {
+  if (Kind == FunctionNameKind::None)
+    return false;
+  // The address may correspond to instruction in some inlined function,
+  // so we have to build the chain of inlined functions and take the
+  // name of the topmost function in it.
+  const DWARFDebugInfoEntryInlinedChain &InlinedChain =
+      CU->getInlinedChainForAddress(Address);
+  if (InlinedChain.DIEs.size() == 0)
+    return false;
+  const DWARFDebugInfoEntryMinimal &TopFunctionDIE = InlinedChain.DIEs[0];
+  if (const char *Name =
+          TopFunctionDIE.getSubroutineName(InlinedChain.U, Kind)) {
+    FunctionName = Name;
+    return true;
+  }
+  return false;
+}
+
+DILineInfo DWARFContext::getLineInfoForAddress(uint64_t Address,
+                                               DILineInfoSpecifier Spec) {
+  DILineInfo Result;
+
+  DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
+  if (!CU)
+    return Result;
+  getFunctionNameForAddress(CU, Address, Spec.FNKind, Result.FunctionName);
+  if (Spec.FLIKind != FileLineInfoKind::None) {
+    const DWARFLineTable *LineTable = getLineTableForCompileUnit(CU);
+    getFileLineInfoForCompileUnit(CU, LineTable, Address, Spec.FLIKind, Result);
+  }
+  return Result;
+}
+
+DILineInfoTable
+DWARFContext::getLineInfoForAddressRange(uint64_t Address, uint64_t Size,
+                                         DILineInfoSpecifier Spec) {
+  DILineInfoTable  Lines;
+  DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
+  if (!CU)
+    return Lines;
+
+  std::string FunctionName = "<invalid>";
+  getFunctionNameForAddress(CU, Address, Spec.FNKind, FunctionName);
+
+  // If the Specifier says we don't need FileLineInfo, just
+  // return the top-most function at the starting address.
+  if (Spec.FLIKind == FileLineInfoKind::None) {
+    DILineInfo Result;
+    Result.FunctionName = FunctionName;
+    Lines.push_back(std::make_pair(Address, Result));
+    return Lines;
+  }
+
+  const DWARFLineTable *LineTable = getLineTableForCompileUnit(CU);
+
+  // Get the index of row we're looking for in the line table.
+  std::vector<uint32_t> RowVector;
+  if (!LineTable->lookupAddressRange(Address, Size, RowVector))
+    return Lines;
+
+  for (uint32_t RowIndex : RowVector) {
+    // Take file number and line/column from the row.
+    const DWARFDebugLine::Row &Row = LineTable->Rows[RowIndex];
+    DILineInfo Result;
+    getFileNameForCompileUnit(CU, LineTable, Row.File, Spec.FLIKind,
+                              Result.FileName);
+    Result.FunctionName = FunctionName;
+    Result.Line = Row.Line;
+    Result.Column = Row.Column;
+    Lines.push_back(std::make_pair(Row.Address, Result));
+  }
+
+  return Lines;
+}
+
+DIInliningInfo
+DWARFContext::getInliningInfoForAddress(uint64_t Address,
+                                        DILineInfoSpecifier Spec) {
+  DIInliningInfo InliningInfo;
+
+  DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
+  if (!CU)
+    return InliningInfo;
+
+  const DWARFLineTable *LineTable = nullptr;
+  const DWARFDebugInfoEntryInlinedChain &InlinedChain =
+      CU->getInlinedChainForAddress(Address);
+  if (InlinedChain.DIEs.size() == 0) {
+    // If there is no DIE for address (e.g. it is in unavailable .dwo file),
+    // try to at least get file/line info from symbol table.
+    if (Spec.FLIKind != FileLineInfoKind::None) {
+      DILineInfo Frame;
+      LineTable = getLineTableForCompileUnit(CU);
+      if (getFileLineInfoForCompileUnit(CU, LineTable, Address, Spec.FLIKind,
+                                        Frame)) {
+        InliningInfo.addFrame(Frame);
+      }
+    }
+    return InliningInfo;
+  }
+
+  uint32_t CallFile = 0, CallLine = 0, CallColumn = 0;
+  for (uint32_t i = 0, n = InlinedChain.DIEs.size(); i != n; i++) {
+    const DWARFDebugInfoEntryMinimal &FunctionDIE = InlinedChain.DIEs[i];
+    DILineInfo Frame;
+    // Get function name if necessary.
+    if (const char *Name =
+            FunctionDIE.getSubroutineName(InlinedChain.U, Spec.FNKind))
+      Frame.FunctionName = Name;
+    if (Spec.FLIKind != FileLineInfoKind::None) {
+      if (i == 0) {
+        // For the topmost frame, initialize the line table of this
+        // compile unit and fetch file/line info from it.
+        LineTable = getLineTableForCompileUnit(CU);
+        // For the topmost routine, get file/line info from line table.
+        getFileLineInfoForCompileUnit(CU, LineTable, Address, Spec.FLIKind,
+                                      Frame);
+      } else {
+        // Otherwise, use call file, call line and call column from
+        // previous DIE in inlined chain.
+        getFileNameForCompileUnit(CU, LineTable, CallFile, Spec.FLIKind,
+                                  Frame.FileName);
+        Frame.Line = CallLine;
+        Frame.Column = CallColumn;
+      }
+      // Get call file/line/column of a current DIE.
+      if (i + 1 < n) {
+        FunctionDIE.getCallerFrame(InlinedChain.U, CallFile, CallLine,
+                                   CallColumn);
+      }
+    }
+    InliningInfo.addFrame(Frame);
+  }
+  return InliningInfo;
+}
+
+static bool consumeCompressedDebugSectionHeader(StringRef &data,
+                                                uint64_t &OriginalSize) {
+  // Consume "ZLIB" prefix.
+  if (!data.startswith("ZLIB"))
+    return false;
+  data = data.substr(4);
+  // Consume uncompressed section size (big-endian 8 bytes).
+  DataExtractor extractor(data, false, 8);
+  uint32_t Offset = 0;
+  OriginalSize = extractor.getU64(&Offset);
+  if (Offset == 0)
+    return false;
+  data = data.substr(Offset);
+  return true;
+}
+
+DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj)
+    : IsLittleEndian(Obj->isLittleEndian()),
+      AddressSize(Obj->getBytesInAddress()) {
+  for (const SectionRef &Section : Obj->sections()) {
+    StringRef name;
+    Section.getName(name);
+    StringRef data;
+    Section.getContents(data);
+
+    name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes.
+
+    // Check if debug info section is compressed with zlib.
+    if (name.startswith("zdebug_")) {
+      uint64_t OriginalSize;
+      if (!zlib::isAvailable() ||
+          !consumeCompressedDebugSectionHeader(data, OriginalSize))
+        continue;
+      UncompressedSections.resize(UncompressedSections.size() + 1);
+      if (zlib::uncompress(data, UncompressedSections.back(), OriginalSize) !=
+          zlib::StatusOK) {
+        UncompressedSections.pop_back();
+        continue;
+      }
+      // Make data point to uncompressed section contents and save its contents.
+      name = name.substr(1);
+      data = UncompressedSections.back();
+    }
+
+    StringRef *SectionData =
+        StringSwitch<StringRef *>(name)
+            .Case("debug_info", &InfoSection.Data)
+            .Case("debug_abbrev", &AbbrevSection)
+            .Case("debug_loc", &LocSection.Data)
+            .Case("debug_line", &LineSection.Data)
+            .Case("debug_aranges", &ARangeSection)
+            .Case("debug_frame", &DebugFrameSection)
+            .Case("debug_str", &StringSection)
+            .Case("debug_ranges", &RangeSection)
+            .Case("debug_pubnames", &PubNamesSection)
+            .Case("debug_pubtypes", &PubTypesSection)
+            .Case("debug_gnu_pubnames", &GnuPubNamesSection)
+            .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)
+            .Case("debug_addr", &AddrSection)
+            // Any more debug info sections go here.
+            .Default(nullptr);
+    if (SectionData) {
+      *SectionData = data;
+      if (name == "debug_ranges") {
+        // FIXME: Use the other dwo range section when we emit it.
+        RangeDWOSection = data;
+      }
+    } else if (name == "debug_types") {
+      // Find debug_types data by section rather than name as there are
+      // multiple, comdat grouped, debug_types sections.
+      TypesSections[Section].Data = data;
+    } else if (name == "debug_types.dwo") {
+      TypesDWOSections[Section].Data = data;
+    }
+
+    section_iterator RelocatedSection = Section.getRelocatedSection();
+    if (RelocatedSection == Obj->section_end())
+      continue;
+
+    StringRef RelSecName;
+    RelocatedSection->getName(RelSecName);
+    RelSecName = RelSecName.substr(
+        RelSecName.find_first_not_of("._")); // Skip . and _ prefixes.
+
+    // TODO: Add support for relocations in other sections as needed.
+    // Record relocations for the debug_info and debug_line sections.
+    RelocAddrMap *Map = StringSwitch<RelocAddrMap*>(RelSecName)
+        .Case("debug_info", &InfoSection.Relocs)
+        .Case("debug_loc", &LocSection.Relocs)
+        .Case("debug_info.dwo", &InfoDWOSection.Relocs)
+        .Case("debug_line", &LineSection.Relocs)
+        .Default(nullptr);
+    if (!Map) {
+      // Find debug_types relocs by section rather than name as there are
+      // multiple, comdat grouped, debug_types sections.
+      if (RelSecName == "debug_types")
+        Map = &TypesSections[*RelocatedSection].Relocs;
+      else if (RelSecName == "debug_types.dwo")
+        Map = &TypesDWOSections[*RelocatedSection].Relocs;
+      else
+        continue;
+    }
+
+    if (Section.relocation_begin() != Section.relocation_end()) {
+      uint64_t SectionSize;
+      RelocatedSection->getSize(SectionSize);
+      for (const RelocationRef &Reloc : Section.relocations()) {
+        uint64_t Address;
+        Reloc.getOffset(Address);
+        uint64_t Type;
+        Reloc.getType(Type);
+        uint64_t SymAddr = 0;
+        // ELF relocations may need the symbol address
+        if (Obj->isELF()) {
+          object::symbol_iterator Sym = Reloc.getSymbol();
+          Sym->getAddress(SymAddr);
+        }
+
+        object::RelocVisitor V(Obj->getFileFormatName());
+        // The section address is always 0 for debug sections.
+        object::RelocToApply R(V.visit(Type, Reloc, 0, SymAddr));
+        if (V.error()) {
+          SmallString<32> Name;
+          std::error_code ec(Reloc.getTypeName(Name));
+          if (ec) {
+            errs() << "Aaaaaa! Nameless relocation! Aaaaaa!\n";
+          }
+          errs() << "error: failed to compute relocation: "
+                 << Name << "\n";
+          continue;
+        }
+
+        if (Address + R.Width > SectionSize) {
+          errs() << "error: " << R.Width << "-byte relocation starting "
+                 << Address << " bytes into section " << name << " which is "
+                 << SectionSize << " bytes long.\n";
+          continue;
+        }
+        if (R.Width > 8) {
+          errs() << "error: can't handle a relocation of more than 8 bytes at "
+                    "a time.\n";
+          continue;
+        }
+        DEBUG(dbgs() << "Writing " << format("%p", R.Value)
+                     << " at " << format("%p", Address)
+                     << " with width " << format("%d", R.Width)
+                     << "\n");
+        Map->insert(std::make_pair(Address, std::make_pair(R.Width, R.Value)));
+      }
+    }
+  }
+}
+
+void DWARFContextInMemory::anchor() { }