General cleanup to minimize the .debug_types patch

This cleanup is designed to make the https://reviews.llvm.org/D32167 patch smaller and easier to read.

Cleanup in this patch:

Allow DWARFUnit subclasses to hand out the data that should be used when decoding data for a DIE. The information might be in .debug_info or could be in .debug_types. There is a new virtual function on DWARFUnit that each subclass must override:

virtual const lldb_private::DWARFDataExtractor &DWARFUnit::GetData() const;
This allows DWARFCompileUnit and eventually DWARFTypeUnit to hand out different data to be used when decoding the DIE information.

Add a new pure virtual function to get the size of the DWARF unit header:

virtual uint32_t DWARFUnit::GetHeaderByteSize() const = 0;
This allows DWARFCompileUnit and eventually DWARFTypeUnit to hand out different offsets where the first DIE starts when decoding DIE information from the unit.

Added a new function to DWARFDataExtractor to get the size of an offset:

size_t DWARFDataExtractor::GetDWARFSizeOfOffset() const;
Removed dead dumping and parsing code in the DWARFDebugInfo class.
Inlined a bunch of calls in DWARFUnit for accessors that were just returning integer member variables.
Renamed DWARFUnit::Size() to DWARFUnit::GetHeaderByteSize() as it clearly states what it is doing and makes more sense.

Differential Revision: https://reviews.llvm.org/D46606

llvm-svn: 331892

lldb/include/lldb/lldb-forward.h

@@ -76,6 +76,7 @@ class ConnectionFileDescriptor;
 class ConstString;
 class CXXSyntheticChildren;
 class DWARFCallFrameInfo;
+class DWARFDataExtractor;
 class DWARFExpression;
 class DataBuffer;
 class DataEncoder;

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp

@@ -2868,8 +2868,7 @@ bool DWARFASTParserClang::ParseChildMembers(
               if (form_value.BlockData()) {
                 Value initialValue(0);
                 Value memberOffset(0);
-                const DWARFDataExtractor &debug_info_data =
+                const DWARFDataExtractor &debug_info_data = die.GetData();
-                    die.GetDWARF()->get_debug_info_data();
                 uint32_t block_length = form_value.Unsigned();
                 uint32_t block_offset =
                     form_value.BlockData() - debug_info_data.GetDataStart();
@@ -3330,8 +3329,7 @@ bool DWARFASTParserClang::ParseChildMembers(
               if (form_value.BlockData()) {
                 Value initialValue(0);
                 Value memberOffset(0);
-                const DWARFDataExtractor &debug_info_data =
+                const DWARFDataExtractor &debug_info_data = die.GetData();
-                    die.GetDWARF()->get_debug_info_data();
                 uint32_t block_length = form_value.Unsigned();
                 uint32_t block_offset =
                     form_value.BlockData() - debug_info_data.GetDataStart();

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserGo.cpp

@@ -655,8 +655,7 @@ size_t DWARFASTParserGo::ParseChildMembers(const SymbolContext &sc,
               if (form_value.BlockData()) {
                 Value initialValue(0);
                 Value memberOffset(0);
-                const DWARFDataExtractor &debug_info_data =
+                const DWARFDataExtractor &debug_info_data = die.GetData();
-                    die.GetDWARF()->get_debug_info_data();
                 uint32_t block_length = form_value.Unsigned();
                 uint32_t block_offset =
                     form_value.BlockData() - debug_info_data.GetDataStart();

lldb/source/Plugins/SymbolFile/DWARF/DWARFAttribute.cpp

@@ -52,8 +52,7 @@ bool DWARFAttributes::ExtractFormValueAtIndex(
   form_value.SetCompileUnit(cu);
   form_value.SetForm(FormAtIndex(i));
   lldb::offset_t offset = DIEOffsetAtIndex(i);
-  return form_value.ExtractValue(
+  return form_value.ExtractValue(cu->GetData(), &offset);
-      cu->GetSymbolFileDWARF()->get_debug_info_data(), &offset);
 }
 
 uint64_t DWARFAttributes::FormValueAsUnsigned(dw_attr_t attr,

lldb/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp

@@ -20,14 +20,10 @@ DWARFCompileUnit::DWARFCompileUnit(SymbolFileDWARF *dwarf2Data)
     : DWARFUnit(dwarf2Data) {}
 
 DWARFUnitSP DWARFCompileUnit::Extract(SymbolFileDWARF *dwarf2Data,
-    lldb::offset_t *offset_ptr) {
+                                      const DWARFDataExtractor &debug_info,
+                                      lldb::offset_t *offset_ptr) {
   // std::make_shared would require the ctor to be public.
   std::shared_ptr<DWARFCompileUnit> cu_sp(new DWARFCompileUnit(dwarf2Data));
-  // Out of memory?
-  if (cu_sp.get() == NULL)
-    return nullptr;
-
-  const DWARFDataExtractor &debug_info = dwarf2Data->get_debug_info_data();
 
   cu_sp->m_offset = *offset_ptr;
 
@@ -67,3 +63,8 @@ void DWARFCompileUnit::Dump(Stream *s) const {
             m_offset, m_length, m_version, GetAbbrevOffset(), m_addr_size,
             GetNextCompileUnitOffset());
 }
+
+
+const lldb_private::DWARFDataExtractor &DWARFCompileUnit::GetData() const {
+  return m_dwarf->get_debug_info_data();
+}

lldb/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.h

@@ -17,9 +17,30 @@ class DWARFCompileUnit : public DWARFUnit {
 
 public:
   static DWARFUnitSP Extract(SymbolFileDWARF *dwarf2Data,
-      lldb::offset_t *offset_ptr);
+                             const lldb_private::DWARFDataExtractor &debug_info,
+                             lldb::offset_t *offset_ptr);
   void Dump(lldb_private::Stream *s) const override;
 
+  //------------------------------------------------------------------
+  /// Get the data that contains the DIE information for this unit.
+  ///
+  /// @return
+  ///   The correct data (.debug_types for DWARF 4 and earlier, and
+  ///   .debug_info for DWARF 5 and later) for the DIE information in
+  ///   this unit.
+  //------------------------------------------------------------------
+  const lldb_private::DWARFDataExtractor &GetData() const override;
+
+  //------------------------------------------------------------------
+  /// Get the size in bytes of the header.
+  ///
+  /// @return
+  ///     Byte size of the compile unit header
+  //------------------------------------------------------------------
+  uint32_t GetHeaderByteSize() const override {
+    return m_is_dwarf64 ? 23 : 11;
+  }
+
 private:
   DWARFCompileUnit(SymbolFileDWARF *dwarf2Data);
   DISALLOW_COPY_AND_ASSIGN(DWARFCompileUnit);

lldb/source/Plugins/SymbolFile/DWARF/DWARFDIE.cpp

@@ -460,3 +460,9 @@ bool operator==(const DWARFDIE &lhs, const DWARFDIE &rhs) {
 bool operator!=(const DWARFDIE &lhs, const DWARFDIE &rhs) {
   return !(lhs == rhs);
 }
+
+const DWARFDataExtractor &DWARFDIE::GetData() const {
+  // Clients must check if this DIE is valid before calling this function.
+  assert(IsValid());
+  return m_cu->GetData();
+}

lldb/source/Plugins/SymbolFile/DWARF/DWARFDIE.h

@@ -86,6 +86,16 @@ public:
   DWARFDIE
   GetContainingDWOModuleDIE() const;
 
+  //----------------------------------------------------------------------
+  // Get the data that contains the attribute values for this DIE. Support
+  // for .debug_types means that any DIE can have its data either in the
+  // .debug_info or the .debug_types section; this method will return the
+  // correct section data.
+  //
+  // Clients must validate that this object is valid before calling this.
+  //----------------------------------------------------------------------
+  const lldb_private::DWARFDataExtractor &GetData() const;
+
   //----------------------------------------------------------------------
   // Accessing information about a DIE
   //----------------------------------------------------------------------

lldb/source/Plugins/SymbolFile/DWARF/DWARFDataExtractor.cpp

@@ -22,6 +22,6 @@ DWARFDataExtractor::GetDWARFInitialLength(lldb::offset_t *offset_ptr) const {
 
 dw_offset_t
 DWARFDataExtractor::GetDWARFOffset(lldb::offset_t *offset_ptr) const {
-  return GetMaxU64(offset_ptr, m_is_dwarf64 ? 8 : 4);
+  return GetMaxU64(offset_ptr, GetDWARFSizeOfOffset());
 }
 }

lldb/source/Plugins/SymbolFile/DWARF/DWARFDataExtractor.h

@@ -29,7 +29,7 @@ public:
   dw_offset_t GetDWARFOffset(lldb::offset_t *offset_ptr) const;
 
   size_t GetDWARFSizeofInitialLength() const { return m_is_dwarf64 ? 12 : 4; }
-
+  size_t GetDWARFSizeOfOffset() const { return m_is_dwarf64 ? 8 : 4; }
   bool IsDWARF64() const { return m_is_dwarf64; }
 
 protected:

lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfo.cpp

@@ -98,7 +98,9 @@ void DWARFDebugInfo::ParseCompileUnitHeadersIfNeeded() {
     if (m_dwarf2Data != NULL) {
       lldb::offset_t offset = 0;
       DWARFUnitSP cu_sp;
-      while ((cu_sp = DWARFCompileUnit::Extract(m_dwarf2Data, &offset))) {
+      const auto &debug_info_data = m_dwarf2Data->get_debug_info_data();
+      while ((cu_sp = DWARFCompileUnit::Extract(m_dwarf2Data, debug_info_data,
+                                                &offset))) {
         m_compile_units.push_back(cu_sp);
 
         offset = cu_sp->GetNextCompileUnitOffset();
@@ -224,268 +226,3 @@ DWARFDebugInfo::GetDIE(const DIERef &die_ref) {
   return DWARFDIE(); // Not found
 }
 
-//----------------------------------------------------------------------
-// Parse
-//
-// Parses the .debug_info section and uses the .debug_abbrev section and
-// various other sections in the SymbolFileDWARF class and calls the supplied
-// callback function each time a compile unit header, or debug information
-// entry is successfully parsed. This function can be used for different tasks
-// such as parsing the file contents into a structured data, dumping, verifying
-// and much more.
-//----------------------------------------------------------------------
-void DWARFDebugInfo::Parse(SymbolFileDWARF *dwarf2Data, Callback callback,
-                           void *userData) {
-  if (dwarf2Data) {
-    lldb::offset_t offset = 0;
-    uint32_t depth = 0;
-    DWARFDebugInfoEntry die;
-
-    DWARFUnitSP cu;
-    while ((cu = DWARFCompileUnit::Extract(dwarf2Data, &offset))) {
-      const dw_offset_t next_cu_offset = cu->GetNextCompileUnitOffset();
-
-      depth = 0;
-      // Call the callback function with no DIE pointer for the compile unit
-      // and get the offset that we are to continue to parse from
-      offset = callback(dwarf2Data, cu.get(), NULL, offset, depth, userData);
-
-      // Make sure we are within our compile unit
-      if (offset < next_cu_offset) {
-        // We are in our compile unit, parse starting at the offset we were
-        // told to parse
-        bool done = false;
-        while (!done && die.Extract(dwarf2Data, cu.get(), &offset)) {
-          // Call the callback function with DIE pointer that falls within the
-          // compile unit
-          offset =
-              callback(dwarf2Data, cu.get(), &die, offset, depth, userData);
-
-          if (die.IsNULL()) {
-            if (depth)
-              --depth;
-            else
-              done = true; // We are done with this compile unit!
-          } else if (die.HasChildren())
-            ++depth;
-        }
-      }
-
-      // Make sure the offset returned is valid, and if not stop parsing.
-      // Returning DW_INVALID_OFFSET from this callback is a good way to end
-      // all parsing
-      if (!dwarf2Data->get_debug_info_data().ValidOffset(offset))
-        break;
-
-      // Make sure we start on a proper
-      offset = next_cu_offset;
-    }
-  }
-}
-
-typedef struct DumpInfo {
-  DumpInfo(Stream *init_strm, uint32_t off, uint32_t depth)
-      : strm(init_strm), die_offset(off), recurse_depth(depth),
-        found_depth(UINT32_MAX), found_die(false), ancestors() {}
-  Stream *strm;
-  const uint32_t die_offset;
-  const uint32_t recurse_depth;
-  uint32_t found_depth;
-  bool found_die;
-  std::vector<DWARFDebugInfoEntry> ancestors;
-
-  DISALLOW_COPY_AND_ASSIGN(DumpInfo);
-} DumpInfo;
-
-//----------------------------------------------------------------------
-// DumpCallback
-//
-// A callback function for the static DWARFDebugInfo::Parse() function
-// that gets called each time a compile unit header or debug information entry
-// is successfully parsed.
-//
-// This function dump DWARF information and obey recurse depth and whether a
-// single DIE is to be dumped (or all of the data).
-//----------------------------------------------------------------------
-static dw_offset_t DumpCallback(SymbolFileDWARF *dwarf2Data,
-                                DWARFUnit *cu, DWARFDebugInfoEntry *die,
-                                const dw_offset_t next_offset,
-                                const uint32_t curr_depth, void *userData) {
-  DumpInfo *dumpInfo = (DumpInfo *)userData;
-  Stream *s = dumpInfo->strm;
-  bool show_parents =
-      s->GetFlags().Test(DWARFDebugInfo::eDumpFlag_ShowAncestors);
-
-  if (die) {
-    // Are we dumping everything?
-    if (dumpInfo->die_offset == DW_INVALID_OFFSET) {
-      // Yes we are dumping everything. Obey our recurse level though
-      if (curr_depth < dumpInfo->recurse_depth)
-        die->Dump(dwarf2Data, cu, *s, 0);
-    } else {
-      // We are dumping a specific DIE entry by offset
-      if (dumpInfo->die_offset == die->GetOffset()) {
-        // We found the DIE we were looking for, dump it!
-        if (show_parents) {
-          s->SetIndentLevel(0);
-          const uint32_t num_ancestors = dumpInfo->ancestors.size();
-          if (num_ancestors > 0) {
-            for (uint32_t i = 0; i < num_ancestors - 1; ++i) {
-              dumpInfo->ancestors[i].Dump(dwarf2Data, cu, *s, 0);
-              s->IndentMore();
-            }
-          }
-        }
-
-        dumpInfo->found_depth = curr_depth;
-
-        die->Dump(dwarf2Data, cu, *s, 0);
-
-        // Note that we found the DIE we were looking for
-        dumpInfo->found_die = true;
-
-        // Since we are dumping a single DIE, if there are no children we are
-        // done!
-        if (!die->HasChildren() || dumpInfo->recurse_depth == 0)
-          return DW_INVALID_OFFSET; // Return an invalid address to end parsing
-      } else if (dumpInfo->found_die) {
-        // Are we done with all the children?
-        if (curr_depth <= dumpInfo->found_depth)
-          return DW_INVALID_OFFSET;
-
-        // We have already found our DIE and are printing it's children. Obey
-        // our recurse depth and return an invalid offset if we get done
-        // dumping all of the children
-        if (dumpInfo->recurse_depth == UINT32_MAX ||
-            curr_depth <= dumpInfo->found_depth + dumpInfo->recurse_depth)
-          die->Dump(dwarf2Data, cu, *s, 0);
-      } else if (dumpInfo->die_offset > die->GetOffset()) {
-        if (show_parents)
-          dumpInfo->ancestors.back() = *die;
-      }
-    }
-
-    // Keep up with our indent level
-    if (die->IsNULL()) {
-      if (show_parents)
-        dumpInfo->ancestors.pop_back();
-
-      if (curr_depth <= 1)
-        return cu->GetNextCompileUnitOffset();
-      else
-        s->IndentLess();
-    } else if (die->HasChildren()) {
-      if (show_parents) {
-        DWARFDebugInfoEntry null_die;
-        dumpInfo->ancestors.push_back(null_die);
-      }
-      s->IndentMore();
-    }
-  } else {
-    if (cu == NULL)
-      s->PutCString("NULL - cu");
-    // We have a compile unit, reset our indent level to zero just in case
-    s->SetIndentLevel(0);
-
-    // See if we are dumping everything?
-    if (dumpInfo->die_offset == DW_INVALID_OFFSET) {
-      // We are dumping everything
-      if (cu) {
-        cu->Dump(s);
-        return cu->GetFirstDIEOffset(); // Return true to parse all DIEs in this
-                                        // Compile Unit
-      } else {
-        return DW_INVALID_OFFSET;
-      }
-    } else {
-      if (show_parents) {
-        dumpInfo->ancestors.clear();
-        dumpInfo->ancestors.resize(1);
-      }
-
-      // We are dumping only a single DIE possibly with it's children and we
-      // must find it's compile unit before we can dump it properly
-      if (cu && dumpInfo->die_offset < cu->GetFirstDIEOffset()) {
-        // Not found, maybe the DIE offset provided wasn't correct?
-        //  *ostrm_ptr << "DIE at offset " << HEX32 << dumpInfo->die_offset << "
-        //  was not found." << endl;
-        return DW_INVALID_OFFSET;
-      } else {
-        // See if the DIE is in this compile unit?
-        if (cu && dumpInfo->die_offset < cu->GetNextCompileUnitOffset()) {
-          return next_offset;
-          //  // We found our compile unit that contains our DIE, just skip to
-          //  dumping the requested DIE...
-          //  return dumpInfo->die_offset;
-        } else {
-          // Skip to the next compile unit as the DIE isn't in the current one!
-          if (cu) {
-            return cu->GetNextCompileUnitOffset();
-          } else {
-            return DW_INVALID_OFFSET;
-          }
-        }
-      }
-    }
-  }
-
-  // Just return the current offset to parse the next CU or DIE entry
-  return next_offset;
-}
-
-//----------------------------------------------------------------------
-// Dump
-//
-// Dump the information in the .debug_info section to the specified ostream. If
-// die_offset is valid, a single DIE will be dumped. If the die_offset is
-// invalid, all the DWARF information will be dumped. Both cases will obey a
-// "recurse_depth" or how deep to traverse into the children of each DIE entry.
-// A recurse_depth of zero will dump all compile unit headers. A recurse_depth
-// of 1 will dump all compile unit headers and the DW_TAG_compile unit tags. A
-// depth of 2 will also dump all types and functions.
-//----------------------------------------------------------------------
-void DWARFDebugInfo::Dump(Stream *s, SymbolFileDWARF *dwarf2Data,
-                          const uint32_t die_offset,
-                          const uint32_t recurse_depth) {
-  DumpInfo dumpInfo(s, die_offset, recurse_depth);
-  s->PutCString(".debug_info contents");
-  if (dwarf2Data->get_debug_info_data().GetByteSize() > 0) {
-    if (die_offset == DW_INVALID_OFFSET)
-      s->PutCString(":\n");
-    else {
-      s->Printf(" for DIE entry at .debug_info[0x%8.8x]", die_offset);
-      if (recurse_depth != UINT32_MAX)
-        s->Printf(" recursing %u levels deep.", recurse_depth);
-      s->EOL();
-    }
-  } else {
-    s->PutCString(": < EMPTY >\n");
-    return;
-  }
-  DWARFDebugInfo::Parse(dwarf2Data, DumpCallback, &dumpInfo);
-}
-
-//----------------------------------------------------------------------
-// Dump
-//
-// Dump the contents of this DWARFDebugInfo object as has been parsed and/or
-// modified after it has been parsed.
-//----------------------------------------------------------------------
-void DWARFDebugInfo::Dump(Stream *s, const uint32_t die_offset,
-                          const uint32_t recurse_depth) {
-  DumpInfo dumpInfo(s, die_offset, recurse_depth);
-
-  s->PutCString("Dumping .debug_info section from internal representation\n");
-
-  CompileUnitColl::const_iterator pos;
-  uint32_t curr_depth = 0;
-  ParseCompileUnitHeadersIfNeeded();
-  for (pos = m_compile_units.begin(); pos != m_compile_units.end(); ++pos) {
-    DWARFUnit *cu = pos->get();
-    DumpCallback(m_dwarf2Data, cu, NULL, 0, curr_depth, &dumpInfo);
-
-    const DWARFDIE die = cu->DIE();
-    if (die)
-      die.Dump(s, recurse_depth);
-  }
-}

lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfo.h

@@ -44,13 +44,6 @@ public:
   DWARFDIE GetDIEForDIEOffset(dw_offset_t die_offset);
   DWARFDIE GetDIE(const DIERef &die_ref);
 
-  void Dump(lldb_private::Stream *s, const uint32_t die_offset,
-            const uint32_t recurse_depth);
-  static void Parse(SymbolFileDWARF *parser, Callback callback, void *userData);
-  static void Verify(lldb_private::Stream *s, SymbolFileDWARF *dwarf2Data);
-  static void Dump(lldb_private::Stream *s, SymbolFileDWARF *dwarf2Data,
-                   const uint32_t die_offset, const uint32_t recurse_depth);
-
   enum {
     eDumpFlag_Verbose = (1 << 0),  // Verbose dumping
     eDumpFlag_ShowForm = (1 << 1), // Show the DW_form type

lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp

@@ -196,7 +196,7 @@ bool DWARFDebugInfoEntry::FastExtract(
 bool DWARFDebugInfoEntry::Extract(SymbolFileDWARF *dwarf2Data,
                                   const DWARFUnit *cu,
                                   lldb::offset_t *offset_ptr) {
-  const DWARFDataExtractor &debug_info_data = dwarf2Data->get_debug_info_data();
+  const DWARFDataExtractor &debug_info_data = cu->GetData();
   //    const DWARFDataExtractor& debug_str_data =
   //    dwarf2Data->get_debug_str_data();
   const uint32_t cu_end_offset = cu->GetNextCompileUnitOffset();
@@ -403,8 +403,7 @@ bool DWARFDebugInfoEntry::GetDIENamesAndRanges(
   lldb::ModuleSP module = dwarf2Data->GetObjectFile()->GetModule();
 
   if (abbrevDecl) {
-    const DWARFDataExtractor &debug_info_data =
+    const DWARFDataExtractor &debug_info_data = cu->GetData();
-        dwarf2Data->get_debug_info_data();
 
     if (!debug_info_data.ValidOffset(offset))
       return false;
@@ -587,7 +586,7 @@ bool DWARFDebugInfoEntry::GetDIENamesAndRanges(
 void DWARFDebugInfoEntry::Dump(SymbolFileDWARF *dwarf2Data,
                                const DWARFUnit *cu, Stream &s,
                                uint32_t recurse_depth) const {
-  const DWARFDataExtractor &debug_info_data = dwarf2Data->get_debug_info_data();
+  const DWARFDataExtractor &debug_info_data = cu->GetData();
   lldb::offset_t offset = m_offset;
 
   if (debug_info_data.ValidOffset(offset)) {
@@ -780,8 +779,7 @@ size_t DWARFDebugInfoEntry::GetAttributes(
   }
 
   if (abbrevDecl) {
-    const DWARFDataExtractor &debug_info_data =
+    const DWARFDataExtractor &debug_info_data = cu->GetData();
-        dwarf2Data->get_debug_info_data();
 
     if (fixed_form_sizes.Empty())
       fixed_form_sizes = DWARFFormValue::GetFixedFormSizesForAddressSize(
@@ -863,8 +861,7 @@ dw_offset_t DWARFDebugInfoEntry::GetAttributeValue(
     uint32_t attr_idx = abbrevDecl->FindAttributeIndex(attr);
 
     if (attr_idx != DW_INVALID_INDEX) {
-      const DWARFDataExtractor &debug_info_data =
+      const DWARFDataExtractor &debug_info_data = cu->GetData();
-          dwarf2Data->get_debug_info_data();
 
       uint32_t idx = 0;
       while (idx < attr_idx)
@@ -1789,8 +1786,7 @@ DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(
         // Make sure the abbreviation code still matches. If it doesn't and the
         // DWARF data was mmap'ed, the backing file might have been modified
         // which is bad news.
-        const uint64_t abbrev_code =
+        const uint64_t abbrev_code = cu->GetData().GetULEB128(&offset);
-            dwarf2Data->get_debug_info_data().GetULEB128(&offset);
 
         if (abbrev_decl->Code() == abbrev_code)
           return abbrev_decl;

lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp

@@ -83,16 +83,16 @@ size_t DWARFUnit::ExtractDIEsIfNeeded(bool cu_die_only) {
   uint32_t depth = 0;
   // We are in our compile unit, parse starting at the offset we were told to
   // parse
-  const DWARFDataExtractor &debug_info_data = m_dwarf->get_debug_info_data();
+  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;
   DWARFFormValue::FixedFormSizes fixed_form_sizes =
       DWARFFormValue::GetFixedFormSizesForAddressSize(GetAddressByteSize(),
-                                                      m_is_dwarf64);
+                                                      IsDWARF64());
   while (offset < next_cu_offset &&
-         die.FastExtract(debug_info_data, this, fixed_form_sizes, &offset)) {
+         die.FastExtract(data, this, fixed_form_sizes, &offset)) {
     //        if (log)
     //            log->Printf("0x%8.8x: %*.*s%s%s",
     //                        die.GetOffset(),
@@ -276,19 +276,14 @@ lldb::user_id_t DWARFUnit::GetID() const {
     return local_id;
 }
 
-uint32_t DWARFUnit::Size() const { return IsDWARF64() ? 23 : 11; }
-
 dw_offset_t DWARFUnit::GetNextCompileUnitOffset() const {
-  return m_offset + (IsDWARF64() ? 12 : 4) + GetLength();
+  return m_offset + GetLengthByteSize() + GetLength();
 }
 
 size_t DWARFUnit::GetDebugInfoSize() const {
-  return (IsDWARF64() ? 12 : 4) + GetLength() - Size();
+  return GetLengthByteSize() + GetLength() - GetHeaderByteSize();
 }
 
-uint32_t DWARFUnit::GetLength() const { return m_length; }
-uint16_t DWARFUnit::GetVersion() const { return m_version; }
-
 const DWARFAbbreviationDeclarationSet *DWARFUnit::GetAbbreviations() const {
   return m_abbrevs;
 }
@@ -297,14 +292,6 @@ dw_offset_t DWARFUnit::GetAbbrevOffset() const {
   return m_abbrevs ? m_abbrevs->GetOffset() : DW_INVALID_OFFSET;
 }
 
-uint8_t DWARFUnit::GetAddressByteSize() const { return m_addr_size; }
-
-dw_addr_t DWARFUnit::GetBaseAddress() const { return m_base_addr; }
-
-dw_addr_t DWARFUnit::GetAddrBase() const { return m_addr_base; }
-
-dw_addr_t DWARFUnit::GetRangesBase() const { return m_ranges_base; }
-
 void DWARFUnit::SetAddrBase(dw_addr_t addr_base,
                             dw_addr_t ranges_base,
                             dw_offset_t base_obj_offset) {
@@ -632,8 +619,6 @@ LanguageType DWARFUnit::GetLanguageType() {
   return m_language_type;
 }
 
-bool DWARFUnit::IsDWARF64() const { return m_is_dwarf64; }
-
 bool DWARFUnit::GetIsOptimized() {
   if (m_is_optimized == eLazyBoolCalculate) {
     const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
@@ -1010,3 +995,4 @@ const DWARFDebugAranges &DWARFUnit::GetFunctionAranges() {
   }
   return *m_func_aranges_ap.get();
 }
+

lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h

@@ -44,28 +44,57 @@ public:
                            uint32_t depth = UINT32_MAX) const;
   bool Verify(lldb_private::Stream *s) const;
   virtual void Dump(lldb_private::Stream *s) const = 0;
+  //------------------------------------------------------------------
+  /// Get the data that contains the DIE information for this unit.
+  ///
+  /// This will return the correct bytes that contain the data for
+  /// this DWARFUnit. It could be .debug_info or .debug_types
+  /// depending on where the data for this unit originates.
+  ///
+  /// @return
+  ///   The correct data for the DIE information in this unit.
+  //------------------------------------------------------------------
+  virtual const lldb_private::DWARFDataExtractor &GetData() const = 0;
+  //------------------------------------------------------------------
+  /// Get the size in bytes of the compile unit header.
+  ///
+  /// @return
+  ///     Byte size of the compile unit header
+  //------------------------------------------------------------------
+  virtual uint32_t GetHeaderByteSize() const = 0;
   // Offset of the initial length field.
   dw_offset_t GetOffset() const { return m_offset; }
   lldb::user_id_t GetID() const;
-  // Size in bytes of the initial length + compile unit header.
+  //------------------------------------------------------------------
-  uint32_t Size() const;
+  /// Get the size in bytes of the length field in the header.
+  ///
+  /// In DWARF32 this is just 4 bytes, and DWARF64 it is 12 where 4
+  /// are 0xFFFFFFFF followed by the actual 64 bit length.
+  ///
+  /// @return
+  ///     Byte size of the compile unit header length field
+  //------------------------------------------------------------------
+  size_t GetLengthByteSize() const { return IsDWARF64() ? 12 : 4; }
+  
   bool ContainsDIEOffset(dw_offset_t die_offset) const {
     return die_offset >= GetFirstDIEOffset() &&
            die_offset < GetNextCompileUnitOffset();
   }
-  dw_offset_t GetFirstDIEOffset() const { return m_offset + Size(); }
+  dw_offset_t GetFirstDIEOffset() const {
+    return m_offset + GetHeaderByteSize();
+  }
   dw_offset_t GetNextCompileUnitOffset() const;
   // Size of the CU data (without initial length and without header).
   size_t GetDebugInfoSize() const;
   // Size of the CU data incl. header but without initial length.
-  uint32_t GetLength() const;
+  uint32_t GetLength() const { return m_length; }
-  uint16_t GetVersion() const;
+  uint16_t GetVersion() const { return m_version; }
   const DWARFAbbreviationDeclarationSet *GetAbbreviations() const;
   dw_offset_t GetAbbrevOffset() const;
-  uint8_t GetAddressByteSize() const;
+  uint8_t GetAddressByteSize() const { return m_addr_size; }
-  dw_addr_t GetBaseAddress() const;
+  dw_addr_t GetBaseAddress() const { return m_base_addr; }
-  dw_addr_t GetAddrBase() const;
+  dw_addr_t GetAddrBase() const { return m_addr_base; }
-  dw_addr_t GetRangesBase() const;
+  dw_addr_t GetRangesBase() const { return m_ranges_base; }
   void SetAddrBase(dw_addr_t addr_base, dw_addr_t ranges_base,
                    dw_offset_t base_obj_offset);
   void ClearDIEs(bool keep_compile_unit_die);
@@ -125,7 +154,7 @@ public:
 
   lldb::LanguageType GetLanguageType();
 
-  bool IsDWARF64() const;
+  bool IsDWARF64() const { return m_is_dwarf64; }
 
   bool GetIsOptimized();
 

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -3758,7 +3758,7 @@ VariableSP SymbolFileDWARF::ParseVariableDIE(const SymbolContext &sc,
               location_is_const_value_data = true;
               // The constant value will be either a block, a data value or a
               // string.
-              const DWARFDataExtractor &debug_info_data = get_debug_info_data();
+              auto debug_info_data = die.GetData();
               if (DWARFFormValue::IsBlockForm(form_value.Form())) {
                 // Retrieve the value as a block expression.
                 uint32_t block_offset =
@@ -3815,13 +3815,12 @@ VariableSP SymbolFileDWARF::ParseVariableDIE(const SymbolContext &sc,
             location_is_const_value_data = false;
             has_explicit_location = true;
             if (DWARFFormValue::IsBlockForm(form_value.Form())) {
-              const DWARFDataExtractor &debug_info_data = get_debug_info_data();
+              auto data = die.GetData();
 
               uint32_t block_offset =
-                  form_value.BlockData() - debug_info_data.GetDataStart();
+                  form_value.BlockData() - data.GetDataStart();
               uint32_t block_length = form_value.Unsigned();
-              location.CopyOpcodeData(module, get_debug_info_data(),
+              location.CopyOpcodeData(module, data, block_offset, block_length);
-                                      block_offset, block_length);
             } else {
               const DWARFDataExtractor &debug_loc_data = get_debug_loc_data();
               const dw_offset_t debug_loc_offset = form_value.Unsigned();