Import LLVM 10.0.0 release including clang, lld and lldb.

ok hackroom
tested by plenty

1 files changed, 980 insertions, 0 deletions

diff --git a/gnu/llvm/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp b/gnu/llvm/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
new file mode 100644
index 00000000000..22e3e40dac9
--- /dev/null
+++ b/gnu/llvm/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
@@ -0,0 +1,980 @@
+//===-- DWARFUnit.cpp -------------------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "DWARFUnit.h"
+
+#include "lldb/Core/Module.h"
+#include "lldb/Host/StringConvert.h"
+#include "lldb/Symbol/ObjectFile.h"
+#include "lldb/Utility/LLDBAssert.h"
+#include "lldb/Utility/StreamString.h"
+#include "lldb/Utility/Timer.h"
+#include "llvm/Object/Error.h"
+
+#include "DWARFCompileUnit.h"
+#include "DWARFDebugAranges.h"
+#include "DWARFDebugInfo.h"
+#include "DWARFTypeUnit.h"
+#include "LogChannelDWARF.h"
+#include "SymbolFileDWARFDwo.h"
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace std;
+
+extern int g_verbose;
+
+DWARFUnit::DWARFUnit(SymbolFileDWARF &dwarf, lldb::user_id_t uid,
+                     const DWARFUnitHeader &header,
+                     const DWARFAbbreviationDeclarationSet &abbrevs,
+                     DIERef::Section section, bool is_dwo)
+    : UserID(uid), m_dwarf(dwarf), m_header(header), m_abbrevs(&abbrevs),
+      m_cancel_scopes(false), m_section(section), m_is_dwo(is_dwo) {}
+
+DWARFUnit::~DWARFUnit() = default;
+
+// Parses first DIE of a compile unit.
+void DWARFUnit::ExtractUnitDIEIfNeeded() {
+  {
+    llvm::sys::ScopedReader lock(m_first_die_mutex);
+    if (m_first_die)
+      return; // Already parsed
+  }
+  llvm::sys::ScopedWriter lock(m_first_die_mutex);
+  if (m_first_die)
+    return; // Already parsed
+
+  static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
+  Timer scoped_timer(func_cat, "%8.8x: DWARFUnit::ExtractUnitDIEIfNeeded()",
+                     GetOffset());
+
+  // Set the offset to that of the first DIE and calculate the start of the
+  // next compilation unit header.
+  lldb::offset_t offset = GetFirstDIEOffset();
+
+  // We are in our compile unit, parse starting at the offset we were told to
+  // parse
+  const DWARFDataExtractor &data = GetData();
+  if (offset < GetNextUnitOffset() &&
+      m_first_die.Extract(data, this, &offset)) {
+    AddUnitDIE(m_first_die);
+    return;
+  }
+}
+
+// Parses a compile unit and indexes its DIEs if it hasn't already been done.
+// It will leave this compile unit extracted forever.
+void DWARFUnit::ExtractDIEsIfNeeded() {
+  m_cancel_scopes = true;
+
+  {
+    llvm::sys::ScopedReader lock(m_die_array_mutex);
+    if (!m_die_array.empty())
+      return; // Already parsed
+  }
+  llvm::sys::ScopedWriter lock(m_die_array_mutex);
+  if (!m_die_array.empty())
+    return; // Already parsed
+
+  ExtractDIEsRWLocked();
+}
+
+// Parses a compile unit and indexes its DIEs if it hasn't already been done.
+// It will clear this compile unit after returned instance gets out of scope,
+// no other ScopedExtractDIEs instance is running for this compile unit
+// and no ExtractDIEsIfNeeded() has been executed during this ScopedExtractDIEs
+// lifetime.
+DWARFUnit::ScopedExtractDIEs DWARFUnit::ExtractDIEsScoped() {
+  ScopedExtractDIEs scoped(*this);
+
+  {
+    llvm::sys::ScopedReader lock(m_die_array_mutex);
+    if (!m_die_array.empty())
+      return scoped; // Already parsed
+  }
+  llvm::sys::ScopedWriter lock(m_die_array_mutex);
+  if (!m_die_array.empty())
+    return scoped; // Already parsed
+
+  // Otherwise m_die_array would be already populated.
+  lldbassert(!m_cancel_scopes);
+
+  ExtractDIEsRWLocked();
+  scoped.m_clear_dies = true;
+  return scoped;
+}
+
+DWARFUnit::ScopedExtractDIEs::ScopedExtractDIEs(DWARFUnit &cu) : m_cu(&cu) {
+  m_cu->m_die_array_scoped_mutex.lock_shared();
+}
+
+DWARFUnit::ScopedExtractDIEs::~ScopedExtractDIEs() {
+  if (!m_cu)
+    return;
+  m_cu->m_die_array_scoped_mutex.unlock_shared();
+  if (!m_clear_dies || m_cu->m_cancel_scopes)
+    return;
+  // Be sure no other ScopedExtractDIEs is running anymore.
+  llvm::sys::ScopedWriter lock_scoped(m_cu->m_die_array_scoped_mutex);
+  llvm::sys::ScopedWriter lock(m_cu->m_die_array_mutex);
+  if (m_cu->m_cancel_scopes)
+    return;
+  m_cu->ClearDIEsRWLocked();
+}
+
+DWARFUnit::ScopedExtractDIEs::ScopedExtractDIEs(ScopedExtractDIEs &&rhs)
+    : m_cu(rhs.m_cu), m_clear_dies(rhs.m_clear_dies) {
+  rhs.m_cu = nullptr;
+}
+
+DWARFUnit::ScopedExtractDIEs &DWARFUnit::ScopedExtractDIEs::operator=(
+    DWARFUnit::ScopedExtractDIEs &&rhs) {
+  m_cu = rhs.m_cu;
+  rhs.m_cu = nullptr;
+  m_clear_dies = rhs.m_clear_dies;
+  return *this;
+}
+
+// Parses a compile unit and indexes its DIEs, m_die_array_mutex must be
+// held R/W and m_die_array must be empty.
+void DWARFUnit::ExtractDIEsRWLocked() {
+  llvm::sys::ScopedWriter first_die_lock(m_first_die_mutex);
+
+  static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
+  Timer scoped_timer(func_cat, "%8.8x: DWARFUnit::ExtractDIEsIfNeeded()",
+                     GetOffset());
+
+  // Set the offset to that of the first DIE and calculate the start of the
+  // next compilation unit header.
+  lldb::offset_t offset = GetFirstDIEOffset();
+  lldb::offset_t next_cu_offset = GetNextUnitOffset();
+
+  DWARFDebugInfoEntry die;
+
+  uint32_t depth = 0;
+  // We are in our compile unit, parse starting at the offset we were told to
+  // parse
+  const DWARFDataExtractor &data = GetData();
+  std::vector<uint32_t> die_index_stack;
+  die_index_stack.reserve(32);
+  die_index_stack.push_back(0);
+  bool prev_die_had_children = false;
+  while (offset < next_cu_offset && die.Extract(data, this, &offset)) {
+    const bool null_die = die.IsNULL();
+    if (depth == 0) {
+      assert(m_die_array.empty() && "Compile unit DIE already added");
+
+      // The average bytes per DIE entry has been seen to be around 14-20 so
+      // lets pre-reserve half of that since we are now stripping the NULL
+      // tags.
+
+      // Only reserve the memory if we are adding children of the main
+      // compile unit DIE. The compile unit DIE is always the first entry, so
+      // if our size is 1, then we are adding the first compile unit child
+      // DIE and should reserve the memory.
+      m_die_array.reserve(GetDebugInfoSize() / 24);
+      m_die_array.push_back(die);
+
+      if (!m_first_die)
+        AddUnitDIE(m_die_array.front());
+
+      // With -fsplit-dwarf-inlining, clang will emit non-empty skeleton compile
+      // units. We are not able to access these DIE *and* the dwo file
+      // simultaneously. We also don't need to do that as the dwo file will
+      // contain a superset of information. So, we don't even attempt to parse
+      // any remaining DIEs.
+      if (m_dwo_symbol_file) {
+        m_die_array.front().SetHasChildren(false);
+        break;
+      }
+
+    } else {
+      if (null_die) {
+        if (prev_die_had_children) {
+          // This will only happen if a DIE says is has children but all it
+          // contains is a NULL tag. Since we are removing the NULL DIEs from
+          // the list (saves up to 25% in C++ code), we need a way to let the
+          // DIE know that it actually doesn't have children.
+          if (!m_die_array.empty())
+            m_die_array.back().SetHasChildren(false);
+        }
+      } else {
+        die.SetParentIndex(m_die_array.size() - die_index_stack[depth - 1]);
+
+        if (die_index_stack.back())
+          m_die_array[die_index_stack.back()].SetSiblingIndex(
+              m_die_array.size() - die_index_stack.back());
+
+        // Only push the DIE if it isn't a NULL DIE
+        m_die_array.push_back(die);
+      }
+    }
+
+    if (null_die) {
+      // NULL DIE.
+      if (!die_index_stack.empty())
+        die_index_stack.pop_back();
+
+      if (depth > 0)
+        --depth;
+      prev_die_had_children = false;
+    } else {
+      die_index_stack.back() = m_die_array.size() - 1;
+      // Normal DIE
+      const bool die_has_children = die.HasChildren();
+      if (die_has_children) {
+        die_index_stack.push_back(0);
+        ++depth;
+      }
+      prev_die_had_children = die_has_children;
+    }
+
+    if (depth == 0)
+      break; // We are done with this compile unit!
+  }
+
+  if (!m_die_array.empty()) {
+    if (m_first_die) {
+      // Only needed for the assertion.
+      m_first_die.SetHasChildren(m_die_array.front().HasChildren());
+      lldbassert(m_first_die == m_die_array.front());
+    }
+    m_first_die = m_die_array.front();
+  }
+
+  m_die_array.shrink_to_fit();
+
+  if (m_dwo_symbol_file) {
+    DWARFUnit *dwo_cu = m_dwo_symbol_file->GetCompileUnit();
+    dwo_cu->ExtractDIEsIfNeeded();
+  }
+}
+
+// This is used when a split dwarf is enabled.
+// A skeleton compilation unit may contain the DW_AT_str_offsets_base attribute
+// that points to the first string offset of the CU contribution to the
+// .debug_str_offsets. At the same time, the corresponding split debug unit also
+// may use DW_FORM_strx* forms pointing to its own .debug_str_offsets.dwo and
+// for that case, we should find the offset (skip the section header).
+static void SetDwoStrOffsetsBase(DWARFUnit *dwo_cu) {
+  lldb::offset_t baseOffset = 0;
+
+  const DWARFDataExtractor &strOffsets =
+      dwo_cu->GetSymbolFileDWARF().GetDWARFContext().getOrLoadStrOffsetsData();
+  uint64_t length = strOffsets.GetU32(&baseOffset);
+  if (length == 0xffffffff)
+    length = strOffsets.GetU64(&baseOffset);
+
+  // Check version.
+  if (strOffsets.GetU16(&baseOffset) < 5)
+    return;
+
+  // Skip padding.
+  baseOffset += 2;
+
+  dwo_cu->SetStrOffsetsBase(baseOffset);
+}
+
+// m_die_array_mutex must be already held as read/write.
+void DWARFUnit::AddUnitDIE(const DWARFDebugInfoEntry &cu_die) {
+  llvm::Optional<uint64_t> addr_base, gnu_addr_base, ranges_base,
+      gnu_ranges_base;
+
+  DWARFAttributes attributes;
+  size_t num_attributes = cu_die.GetAttributes(this, attributes);
+
+  // Extract DW_AT_addr_base first, as other attributes may need it.
+  for (size_t i = 0; i < num_attributes; ++i) {
+    if (attributes.AttributeAtIndex(i) != DW_AT_addr_base)
+      continue;
+    DWARFFormValue form_value;
+    if (attributes.ExtractFormValueAtIndex(i, form_value)) {
+      addr_base = form_value.Unsigned();
+      SetAddrBase(*addr_base);
+      break;
+    }
+  }
+
+  for (size_t i = 0; i < num_attributes; ++i) {
+    dw_attr_t attr = attributes.AttributeAtIndex(i);
+    DWARFFormValue form_value;
+    if (!attributes.ExtractFormValueAtIndex(i, form_value))
+      continue;
+    switch (attr) {
+    case DW_AT_loclists_base:
+      SetLoclistsBase(form_value.Unsigned());
+      break;
+    case DW_AT_rnglists_base:
+      ranges_base = form_value.Unsigned();
+      SetRangesBase(*ranges_base);
+      break;
+    case DW_AT_str_offsets_base:
+      SetStrOffsetsBase(form_value.Unsigned());
+      break;
+    case DW_AT_low_pc:
+      SetBaseAddress(form_value.Address());
+      break;
+    case DW_AT_entry_pc:
+      // If the value was already set by DW_AT_low_pc, don't update it.
+      if (m_base_addr == LLDB_INVALID_ADDRESS)
+        SetBaseAddress(form_value.Address());
+      break;
+    case DW_AT_stmt_list:
+      m_line_table_offset = form_value.Unsigned();
+      break;
+    case DW_AT_GNU_addr_base:
+      gnu_addr_base = form_value.Unsigned();
+      break;
+    case DW_AT_GNU_ranges_base:
+      gnu_ranges_base = form_value.Unsigned();
+      break;
+    }
+  }
+
+  if (m_is_dwo)
+    return;
+
+  std::unique_ptr<SymbolFileDWARFDwo> dwo_symbol_file =
+      m_dwarf.GetDwoSymbolFileForCompileUnit(*this, cu_die);
+  if (!dwo_symbol_file)
+    return;
+
+  DWARFUnit *dwo_cu = dwo_symbol_file->GetCompileUnit();
+  if (!dwo_cu)
+    return; // Can't fetch the compile unit from the dwo file.
+
+  DWARFBaseDIE dwo_cu_die = dwo_cu->GetUnitDIEOnly();
+  if (!dwo_cu_die.IsValid())
+    return; // Can't fetch the compile unit DIE from the dwo file.
+
+  uint64_t main_dwo_id =
+      cu_die.GetAttributeValueAsUnsigned(this, DW_AT_GNU_dwo_id, 0);
+  uint64_t sub_dwo_id =
+      dwo_cu_die.GetAttributeValueAsUnsigned(DW_AT_GNU_dwo_id, 0);
+  if (main_dwo_id != sub_dwo_id)
+    return; // The 2 dwo ID isn't match. Don't use the dwo file as it belongs to
+  // a differectn compilation.
+
+  m_dwo_symbol_file = std::move(dwo_symbol_file);
+
+  // Here for DWO CU we want to use the address base set in the skeleton unit
+  // (DW_AT_addr_base) if it is available and use the DW_AT_GNU_addr_base
+  // otherwise. We do that because pre-DWARF v5 could use the DW_AT_GNU_*
+  // attributes which were applicable to the DWO units. The corresponding
+  // DW_AT_* attributes standardized in DWARF v5 are also applicable to the main
+  // unit in contrast.
+  if (addr_base)
+    dwo_cu->SetAddrBase(*addr_base);
+  else if (gnu_addr_base)
+    dwo_cu->SetAddrBase(*gnu_addr_base);
+
+  if (GetVersion() <= 4 && gnu_ranges_base)
+    dwo_cu->SetRangesBase(*gnu_ranges_base);
+  else if (m_dwo_symbol_file->GetDWARFContext()
+               .getOrLoadRngListsData()
+               .GetByteSize() > 0)
+    dwo_cu->SetRangesBase(llvm::DWARFListTableHeader::getHeaderSize(DWARF32));
+
+  if (GetVersion() >= 5 && m_dwo_symbol_file->GetDWARFContext()
+                                   .getOrLoadLocListsData()
+                                   .GetByteSize() > 0)
+    dwo_cu->SetLoclistsBase(llvm::DWARFListTableHeader::getHeaderSize(DWARF32));
+  dwo_cu->SetBaseAddress(GetBaseAddress());
+
+  for (size_t i = 0; i < m_dwo_symbol_file->DebugInfo()->GetNumUnits(); ++i) {
+    DWARFUnit *unit = m_dwo_symbol_file->DebugInfo()->GetUnitAtIndex(i);
+    SetDwoStrOffsetsBase(unit);
+  }
+}
+
+DWARFDIE DWARFUnit::LookupAddress(const dw_addr_t address) {
+  if (DIE()) {
+    const DWARFDebugAranges &func_aranges = GetFunctionAranges();
+
+    // Re-check the aranges auto pointer contents in case it was created above
+    if (!func_aranges.IsEmpty())
+      return GetDIE(func_aranges.FindAddress(address));
+  }
+  return DWARFDIE();
+}
+
+size_t DWARFUnit::GetDebugInfoSize() const {
+  return GetLengthByteSize() + GetLength() - GetHeaderByteSize();
+}
+
+const DWARFAbbreviationDeclarationSet *DWARFUnit::GetAbbreviations() const {
+  return m_abbrevs;
+}
+
+dw_offset_t DWARFUnit::GetAbbrevOffset() const {
+  return m_abbrevs ? m_abbrevs->GetOffset() : DW_INVALID_OFFSET;
+}
+
+dw_offset_t DWARFUnit::GetLineTableOffset() {
+  ExtractUnitDIEIfNeeded();
+  return m_line_table_offset;
+}
+
+void DWARFUnit::SetAddrBase(dw_addr_t addr_base) { m_addr_base = addr_base; }
+
+// Parse the rangelist table header, including the optional array of offsets
+// following it (DWARF v5 and later).
+template <typename ListTableType>
+static llvm::Expected<ListTableType>
+ParseListTableHeader(const llvm::DWARFDataExtractor &data, uint64_t offset,
+                     DwarfFormat format) {
+  // We are expected to be called with Offset 0 or pointing just past the table
+  // header. Correct Offset in the latter case so that it points to the start
+  // of the header.
+  if (offset > 0) {
+    uint64_t HeaderSize = llvm::DWARFListTableHeader::getHeaderSize(format);
+    if (offset < HeaderSize)
+      return llvm::createStringError(errc::invalid_argument,
+                                     "did not detect a valid"
+                                     " list table with base = 0x%" PRIx64 "\n",
+                                     offset);
+    offset -= HeaderSize;
+  }
+  ListTableType Table;
+  if (llvm::Error E = Table.extractHeaderAndOffsets(data, &offset))
+    return std::move(E);
+  return Table;
+}
+
+void DWARFUnit::SetLoclistsBase(dw_addr_t loclists_base) {
+  m_loclists_base = loclists_base;
+
+  uint64_t header_size = llvm::DWARFListTableHeader::getHeaderSize(DWARF32);
+  if (loclists_base < header_size)
+    return;
+
+  m_loclist_table_header.emplace(".debug_loclists", "locations");
+  uint64_t offset = loclists_base - header_size;
+  if (llvm::Error E = m_loclist_table_header->extract(
+          m_dwarf.GetDWARFContext().getOrLoadLocListsData().GetAsLLVM(),
+          &offset)) {
+    GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
+        "Failed to extract location list table at offset 0x%" PRIx64 ": %s",
+        loclists_base, toString(std::move(E)).c_str());
+  }
+}
+
+std::unique_ptr<llvm::DWARFLocationTable>
+DWARFUnit::GetLocationTable(const DataExtractor &data) const {
+  llvm::DWARFDataExtractor llvm_data(
+      toStringRef(data.GetData()),
+      data.GetByteOrder() == lldb::eByteOrderLittle, data.GetAddressByteSize());
+
+  if (m_is_dwo || GetVersion() >= 5)
+    return std::make_unique<llvm::DWARFDebugLoclists>(llvm_data, GetVersion());
+  return std::make_unique<llvm::DWARFDebugLoc>(llvm_data);
+}
+
+const DWARFDataExtractor &DWARFUnit::GetLocationData() const {
+  DWARFContext &Ctx = GetSymbolFileDWARF().GetDWARFContext();
+  return GetVersion() >= 5 ? Ctx.getOrLoadLocListsData()
+                           : Ctx.getOrLoadLocData();
+}
+
+void DWARFUnit::SetRangesBase(dw_addr_t ranges_base) {
+  m_ranges_base = ranges_base;
+
+  if (GetVersion() < 5)
+    return;
+
+  if (auto table_or_error = ParseListTableHeader<llvm::DWARFDebugRnglistTable>(
+          m_dwarf.GetDWARFContext().getOrLoadRngListsData().GetAsLLVM(),
+          ranges_base, DWARF32))
+    m_rnglist_table = std::move(table_or_error.get());
+  else
+    GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
+        "Failed to extract range list table at offset 0x%" PRIx64 ": %s",
+        ranges_base, toString(table_or_error.takeError()).c_str());
+}
+
+void DWARFUnit::SetStrOffsetsBase(dw_offset_t str_offsets_base) {
+  m_str_offsets_base = str_offsets_base;
+}
+
+// It may be called only with m_die_array_mutex held R/W.
+void DWARFUnit::ClearDIEsRWLocked() {
+  m_die_array.clear();
+  m_die_array.shrink_to_fit();
+
+  if (m_dwo_symbol_file)
+    m_dwo_symbol_file->GetCompileUnit()->ClearDIEsRWLocked();
+}
+
+lldb::ByteOrder DWARFUnit::GetByteOrder() const {
+  return m_dwarf.GetObjectFile()->GetByteOrder();
+}
+
+llvm::Expected<TypeSystem &> DWARFUnit::GetTypeSystem() {
+  return m_dwarf.GetTypeSystemForLanguage(GetLanguageType());
+}
+
+void DWARFUnit::SetBaseAddress(dw_addr_t base_addr) { m_base_addr = base_addr; }
+
+// Compare function DWARFDebugAranges::Range structures
+static bool CompareDIEOffset(const DWARFDebugInfoEntry &die,
+                             const dw_offset_t die_offset) {
+  return die.GetOffset() < die_offset;
+}
+
+// GetDIE()
+//
+// Get the DIE (Debug Information Entry) with the specified offset by first
+// checking if the DIE is contained within this compile unit and grabbing the
+// DIE from this compile unit. Otherwise we grab the DIE from the DWARF file.
+DWARFDIE
+DWARFUnit::GetDIE(dw_offset_t die_offset) {
+  if (die_offset != DW_INVALID_OFFSET) {
+    if (GetDwoSymbolFile())
+      return GetDwoSymbolFile()->GetCompileUnit()->GetDIE(die_offset);
+
+    if (ContainsDIEOffset(die_offset)) {
+      ExtractDIEsIfNeeded();
+      DWARFDebugInfoEntry::const_iterator end = m_die_array.cend();
+      DWARFDebugInfoEntry::const_iterator pos =
+          lower_bound(m_die_array.cbegin(), end, die_offset, CompareDIEOffset);
+      if (pos != end) {
+        if (die_offset == (*pos).GetOffset())
+          return DWARFDIE(this, &(*pos));
+      }
+    } else
+      GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
+          "GetDIE for DIE 0x%" PRIx32 " is outside of its CU 0x%" PRIx32,
+          die_offset, GetOffset());
+  }
+  return DWARFDIE(); // Not found
+}
+
+DWARFUnit &DWARFUnit::GetNonSkeletonUnit() {
+  if (SymbolFileDWARFDwo *dwo = GetDwoSymbolFile())
+    return *dwo->GetCompileUnit();
+  return *this;
+}
+
+uint8_t DWARFUnit::GetAddressByteSize(const DWARFUnit *cu) {
+  if (cu)
+    return cu->GetAddressByteSize();
+  return DWARFUnit::GetDefaultAddressSize();
+}
+
+uint8_t DWARFUnit::GetDefaultAddressSize() { return 4; }
+
+void *DWARFUnit::GetUserData() const { return m_user_data; }
+
+void DWARFUnit::SetUserData(void *d) {
+  m_user_data = d;
+  if (m_dwo_symbol_file)
+    m_dwo_symbol_file->GetCompileUnit()->SetUserData(d);
+}
+
+bool DWARFUnit::Supports_DW_AT_APPLE_objc_complete_type() {
+  return GetProducer() != eProducerLLVMGCC;
+}
+
+bool DWARFUnit::DW_AT_decl_file_attributes_are_invalid() {
+  // llvm-gcc makes completely invalid decl file attributes and won't ever be
+  // fixed, so we need to know to ignore these.
+  return GetProducer() == eProducerLLVMGCC;
+}
+
+bool DWARFUnit::Supports_unnamed_objc_bitfields() {
+  if (GetProducer() == eProducerClang) {
+    const uint32_t major_version = GetProducerVersionMajor();
+    return major_version > 425 ||
+           (major_version == 425 && GetProducerVersionUpdate() >= 13);
+  }
+  return true; // Assume all other compilers didn't have incorrect ObjC bitfield
+               // info
+}
+
+void DWARFUnit::ParseProducerInfo() {
+  m_producer_version_major = UINT32_MAX;
+  m_producer_version_minor = UINT32_MAX;
+  m_producer_version_update = UINT32_MAX;
+
+  const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
+  if (die) {
+
+    const char *producer_cstr =
+        die->GetAttributeValueAsString(this, DW_AT_producer, nullptr);
+    if (producer_cstr) {
+      RegularExpression llvm_gcc_regex(
+          llvm::StringRef("^4\\.[012]\\.[01] \\(Based on Apple "
+                          "Inc\\. build [0-9]+\\) \\(LLVM build "
+                          "[\\.0-9]+\\)$"));
+      if (llvm_gcc_regex.Execute(llvm::StringRef(producer_cstr))) {
+        m_producer = eProducerLLVMGCC;
+      } else if (strstr(producer_cstr, "clang")) {
+        static RegularExpression g_clang_version_regex(
+            llvm::StringRef("clang-([0-9]+)\\.([0-9]+)\\.([0-9]+)"));
+        llvm::SmallVector<llvm::StringRef, 4> matches;
+        if (g_clang_version_regex.Execute(llvm::StringRef(producer_cstr),
+                                          &matches)) {
+          m_producer_version_major =
+              StringConvert::ToUInt32(matches[1].str().c_str(), UINT32_MAX, 10);
+          m_producer_version_minor =
+              StringConvert::ToUInt32(matches[2].str().c_str(), UINT32_MAX, 10);
+          m_producer_version_update =
+              StringConvert::ToUInt32(matches[3].str().c_str(), UINT32_MAX, 10);
+        }
+        m_producer = eProducerClang;
+      } else if (strstr(producer_cstr, "GNU"))
+        m_producer = eProducerGCC;
+    }
+  }
+  if (m_producer == eProducerInvalid)
+    m_producer = eProcucerOther;
+}
+
+DWARFProducer DWARFUnit::GetProducer() {
+  if (m_producer == eProducerInvalid)
+    ParseProducerInfo();
+  return m_producer;
+}
+
+uint32_t DWARFUnit::GetProducerVersionMajor() {
+  if (m_producer_version_major == 0)
+    ParseProducerInfo();
+  return m_producer_version_major;
+}
+
+uint32_t DWARFUnit::GetProducerVersionMinor() {
+  if (m_producer_version_minor == 0)
+    ParseProducerInfo();
+  return m_producer_version_minor;
+}
+
+uint32_t DWARFUnit::GetProducerVersionUpdate() {
+  if (m_producer_version_update == 0)
+    ParseProducerInfo();
+  return m_producer_version_update;
+}
+LanguageType DWARFUnit::LanguageTypeFromDWARF(uint64_t val) {
+  // Note: user languages between lo_user and hi_user must be handled
+  // explicitly here.
+  switch (val) {
+  case DW_LANG_Mips_Assembler:
+    return eLanguageTypeMipsAssembler;
+  case DW_LANG_GOOGLE_RenderScript:
+    return eLanguageTypeExtRenderScript;
+  default:
+    return static_cast<LanguageType>(val);
+  }
+}
+
+LanguageType DWARFUnit::GetLanguageType() {
+  if (m_language_type != eLanguageTypeUnknown)
+    return m_language_type;
+
+  const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
+  if (die)
+    m_language_type = LanguageTypeFromDWARF(
+        die->GetAttributeValueAsUnsigned(this, DW_AT_language, 0));
+  return m_language_type;
+}
+
+bool DWARFUnit::GetIsOptimized() {
+  if (m_is_optimized == eLazyBoolCalculate) {
+    const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
+    if (die) {
+      m_is_optimized = eLazyBoolNo;
+      if (die->GetAttributeValueAsUnsigned(this, DW_AT_APPLE_optimized, 0) ==
+          1) {
+        m_is_optimized = eLazyBoolYes;
+      }
+    }
+  }
+  return m_is_optimized == eLazyBoolYes;
+}
+
+FileSpec::Style DWARFUnit::GetPathStyle() {
+  if (!m_comp_dir)
+    ComputeCompDirAndGuessPathStyle();
+  return m_comp_dir->GetPathStyle();
+}
+
+const FileSpec &DWARFUnit::GetCompilationDirectory() {
+  if (!m_comp_dir)
+    ComputeCompDirAndGuessPathStyle();
+  return *m_comp_dir;
+}
+
+const FileSpec &DWARFUnit::GetAbsolutePath() {
+  if (!m_file_spec)
+    ComputeAbsolutePath();
+  return *m_file_spec;
+}
+
+FileSpec DWARFUnit::GetFile(size_t file_idx) {
+  return m_dwarf.GetFile(*this, file_idx);
+}
+
+// DWARF2/3 suggests the form hostname:pathname for compilation directory.
+// Remove the host part if present.
+static llvm::StringRef
+removeHostnameFromPathname(llvm::StringRef path_from_dwarf) {
+  if (!path_from_dwarf.contains(':'))
+    return path_from_dwarf;
+  llvm::StringRef host, path;
+  std::tie(host, path) = path_from_dwarf.split(':');
+
+  if (host.contains('/'))
+    return path_from_dwarf;
+
+  // check whether we have a windows path, and so the first character is a
+  // drive-letter not a hostname.
+  if (host.size() == 1 && llvm::isAlpha(host[0]) && path.startswith("\\"))
+    return path_from_dwarf;
+
+  return path;
+}
+
+static FileSpec resolveCompDir(const FileSpec &path) {
+  bool is_symlink = SymbolFileDWARF::GetSymlinkPaths().FindFileIndex(
+                        0, path, /*full*/ true) != UINT32_MAX;
+
+  if (!is_symlink)
+    return path;
+
+  namespace fs = llvm::sys::fs;
+  if (fs::get_file_type(path.GetPath(), false) != fs::file_type::symlink_file)
+    return path;
+
+  FileSpec resolved_symlink;
+  const auto error = FileSystem::Instance().Readlink(path, resolved_symlink);
+  if (error.Success())
+    return resolved_symlink;
+
+  return path;
+}
+
+void DWARFUnit::ComputeCompDirAndGuessPathStyle() {
+  m_comp_dir = FileSpec();
+  const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
+  if (!die)
+    return;
+
+  llvm::StringRef comp_dir = removeHostnameFromPathname(
+      die->GetAttributeValueAsString(this, DW_AT_comp_dir, nullptr));
+  if (!comp_dir.empty()) {
+    FileSpec::Style comp_dir_style =
+        FileSpec::GuessPathStyle(comp_dir).getValueOr(FileSpec::Style::native);
+    m_comp_dir = resolveCompDir(FileSpec(comp_dir, comp_dir_style));
+  } else {
+    // Try to detect the style based on the DW_AT_name attribute, but just store
+    // the detected style in the m_comp_dir field.
+    const char *name =
+        die->GetAttributeValueAsString(this, DW_AT_name, nullptr);
+    m_comp_dir = FileSpec(
+        "", FileSpec::GuessPathStyle(name).getValueOr(FileSpec::Style::native));
+  }
+}
+
+void DWARFUnit::ComputeAbsolutePath() {
+  m_file_spec = FileSpec();
+  const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
+  if (!die)
+    return;
+
+  m_file_spec =
+      FileSpec(die->GetAttributeValueAsString(this, DW_AT_name, nullptr),
+               GetPathStyle());
+
+  if (m_file_spec->IsRelative())
+    m_file_spec->MakeAbsolute(GetCompilationDirectory());
+}
+
+SymbolFileDWARFDwo *DWARFUnit::GetDwoSymbolFile() {
+  ExtractUnitDIEIfNeeded();
+  return m_dwo_symbol_file.get();
+}
+
+const DWARFDebugAranges &DWARFUnit::GetFunctionAranges() {
+  if (m_func_aranges_up == nullptr) {
+    m_func_aranges_up.reset(new DWARFDebugAranges());
+    const DWARFDebugInfoEntry *die = DIEPtr();
+    if (die)
+      die->BuildFunctionAddressRangeTable(this, m_func_aranges_up.get());
+
+    if (m_dwo_symbol_file) {
+      DWARFUnit *dwo_cu = m_dwo_symbol_file->GetCompileUnit();
+      const DWARFDebugInfoEntry *dwo_die = dwo_cu->DIEPtr();
+      if (dwo_die)
+        dwo_die->BuildFunctionAddressRangeTable(dwo_cu,
+                                                m_func_aranges_up.get());
+    }
+
+    const bool minimize = false;
+    m_func_aranges_up->Sort(minimize);
+  }
+  return *m_func_aranges_up;
+}
+
+llvm::Expected<DWARFUnitHeader>
+DWARFUnitHeader::extract(const DWARFDataExtractor &data, DIERef::Section section,
+                         lldb::offset_t *offset_ptr) {
+  DWARFUnitHeader header;
+  header.m_offset = *offset_ptr;
+  header.m_length = data.GetDWARFInitialLength(offset_ptr);
+  header.m_version = data.GetU16(offset_ptr);
+  if (header.m_version == 5) {
+    header.m_unit_type = data.GetU8(offset_ptr);
+    header.m_addr_size = data.GetU8(offset_ptr);
+    header.m_abbr_offset = data.GetDWARFOffset(offset_ptr);
+    if (header.m_unit_type == llvm::dwarf::DW_UT_skeleton)
+      header.m_dwo_id = data.GetU64(offset_ptr);
+  } else {
+    header.m_abbr_offset = data.GetDWARFOffset(offset_ptr);
+    header.m_addr_size = data.GetU8(offset_ptr);
+    header.m_unit_type =
+        section == DIERef::Section::DebugTypes ? DW_UT_type : DW_UT_compile;
+  }
+
+  if (header.IsTypeUnit()) {
+    header.m_type_hash = data.GetU64(offset_ptr);
+    header.m_type_offset = data.GetDWARFOffset(offset_ptr);
+  }
+
+  bool length_OK = data.ValidOffset(header.GetNextUnitOffset() - 1);
+  bool version_OK = SymbolFileDWARF::SupportedVersion(header.m_version);
+  bool addr_size_OK = (header.m_addr_size == 4) || (header.m_addr_size == 8);
+  bool type_offset_OK =
+      !header.IsTypeUnit() || (header.m_type_offset <= header.GetLength());
+
+  if (!length_OK)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "Invalid unit length");
+  if (!version_OK)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "Unsupported unit version");
+  if (!addr_size_OK)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "Invalid unit address size");
+  if (!type_offset_OK)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "Type offset out of range");
+
+  return header;
+}
+
+llvm::Expected<DWARFUnitSP>
+DWARFUnit::extract(SymbolFileDWARF &dwarf, user_id_t uid,
+                   const DWARFDataExtractor &debug_info,
+                   DIERef::Section section, lldb::offset_t *offset_ptr) {
+  assert(debug_info.ValidOffset(*offset_ptr));
+
+  auto expected_header =
+      DWARFUnitHeader::extract(debug_info, section, offset_ptr);
+  if (!expected_header)
+    return expected_header.takeError();
+
+  const DWARFDebugAbbrev *abbr = dwarf.DebugAbbrev();
+  if (!abbr)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "No debug_abbrev data");
+
+  bool abbr_offset_OK =
+      dwarf.GetDWARFContext().getOrLoadAbbrevData().ValidOffset(
+          expected_header->GetAbbrOffset());
+  if (!abbr_offset_OK)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "Abbreviation offset for unit is not valid");
+
+  const DWARFAbbreviationDeclarationSet *abbrevs =
+      abbr->GetAbbreviationDeclarationSet(expected_header->GetAbbrOffset());
+  if (!abbrevs)
+    return llvm::make_error<llvm::object::GenericBinaryError>(
+        "No abbrev exists at the specified offset.");
+
+  bool is_dwo = dwarf.GetDWARFContext().isDwo();
+  if (expected_header->IsTypeUnit())
+    return DWARFUnitSP(new DWARFTypeUnit(dwarf, uid, *expected_header, *abbrevs,
+                                         section, is_dwo));
+  return DWARFUnitSP(new DWARFCompileUnit(dwarf, uid, *expected_header,
+                                          *abbrevs, section, is_dwo));
+}
+
+const lldb_private::DWARFDataExtractor &DWARFUnit::GetData() const {
+  return m_section == DIERef::Section::DebugTypes
+             ? m_dwarf.GetDWARFContext().getOrLoadDebugTypesData()
+             : m_dwarf.GetDWARFContext().getOrLoadDebugInfoData();
+}
+
+uint32_t DWARFUnit::GetHeaderByteSize() const {
+  switch (m_header.GetUnitType()) {
+  case llvm::dwarf::DW_UT_compile:
+  case llvm::dwarf::DW_UT_partial:
+    return GetVersion() < 5 ? 11 : 12;
+  case llvm::dwarf::DW_UT_skeleton:
+  case llvm::dwarf::DW_UT_split_compile:
+    return 20;
+  case llvm::dwarf::DW_UT_type:
+  case llvm::dwarf::DW_UT_split_type:
+    return GetVersion() < 5 ? 23 : 24;
+  }
+  llvm_unreachable("invalid UnitType.");
+}
+
+llvm::Expected<DWARFRangeList>
+DWARFUnit::FindRnglistFromOffset(dw_offset_t offset) {
+  if (GetVersion() <= 4) {
+    const DWARFDebugRanges *debug_ranges = m_dwarf.GetDebugRanges();
+    if (!debug_ranges)
+      return llvm::make_error<llvm::object::GenericBinaryError>(
+          "No debug_ranges section");
+    DWARFRangeList ranges;
+    debug_ranges->FindRanges(this, offset, ranges);
+    return ranges;
+  }
+
+  if (!m_rnglist_table)
+    return llvm::createStringError(errc::invalid_argument,
+                                   "missing or invalid range list table");
+
+  auto range_list_or_error = m_rnglist_table->findList(
+      m_dwarf.GetDWARFContext().getOrLoadRngListsData().GetAsLLVM(), offset);
+  if (!range_list_or_error)
+    return range_list_or_error.takeError();
+
+  llvm::Expected<llvm::DWARFAddressRangesVector> llvm_ranges =
+      range_list_or_error->getAbsoluteRanges(
+          llvm::object::SectionedAddress{GetBaseAddress()},
+          [&](uint32_t index) {
+            uint32_t index_size = GetAddressByteSize();
+            dw_offset_t addr_base = GetAddrBase();
+            lldb::offset_t offset = addr_base + index * index_size;
+            return llvm::object::SectionedAddress{
+                m_dwarf.GetDWARFContext().getOrLoadAddrData().GetMaxU64(
+                    &offset, index_size)};
+          });
+  if (!llvm_ranges)
+    return llvm_ranges.takeError();
+
+  DWARFRangeList ranges;
+  for (const llvm::DWARFAddressRange &llvm_range : *llvm_ranges) {
+    ranges.Append(DWARFRangeList::Entry(llvm_range.LowPC,
+                                        llvm_range.HighPC - llvm_range.LowPC));
+  }
+  return ranges;
+}
+
+llvm::Expected<DWARFRangeList>
+DWARFUnit::FindRnglistFromIndex(uint32_t index) {
+  if (llvm::Optional<uint64_t> offset = GetRnglistOffset(index))
+    return FindRnglistFromOffset(*offset);
+  if (m_rnglist_table)
+    return llvm::createStringError(errc::invalid_argument,
+                                   "invalid range list table index %d", index);
+
+  return llvm::createStringError(errc::invalid_argument,
+                                 "missing or invalid range list table");
+}