[LLDB][NFC] Added the interface DWARFExpression::Delegate to break dependencies and reduce lldb-server size

lldb/include/lldb/Expression/DWARFExpression.h

@@ -23,7 +23,7 @@ namespace lldb_private {
 
 namespace plugin {
 namespace dwarf {
-class DWARFUnit;
+class DWARFUnitInterface;
 } // namespace dwarf
 } // namespace plugin
 
@@ -65,20 +65,20 @@ class DWARFExpression {
   /// \return
   ///     The address specified by the operation, if the operation exists, or
   ///     an llvm::Error otherwise.
-  llvm::Expected<lldb::addr_t>
-  GetLocation_DW_OP_addr(const plugin::dwarf::DWARFUnit *dwarf_cu) const;
+  llvm::Expected<lldb::addr_t> GetLocation_DW_OP_addr(
+      const plugin::dwarf::DWARFUnitInterface *dwarf_cu) const;
 
-  bool Update_DW_OP_addr(const plugin::dwarf::DWARFUnit *dwarf_cu,
+  bool Update_DW_OP_addr(const plugin::dwarf::DWARFUnitInterface *dwarf_cu,
                          lldb::addr_t file_addr);
 
   void UpdateValue(uint64_t const_value, lldb::offset_t const_value_byte_size,
                    uint8_t addr_byte_size);
 
-  bool
-  ContainsThreadLocalStorage(const plugin::dwarf::DWARFUnit *dwarf_cu) const;
+  bool ContainsThreadLocalStorage(
+      const plugin::dwarf::DWARFUnitInterface *dwarf_cu) const;
 
   bool LinkThreadLocalStorage(
-      const plugin::dwarf::DWARFUnit *dwarf_cu,
+      const plugin::dwarf::DWARFUnitInterface *dwarf_cu,
       std::function<lldb::addr_t(lldb::addr_t file_addr)> const
           &link_address_callback);
 
@@ -132,13 +132,14 @@ class DWARFExpression {
   static llvm::Expected<Value>
   Evaluate(ExecutionContext *exe_ctx, RegisterContext *reg_ctx,
            lldb::ModuleSP module_sp, const DataExtractor &opcodes,
-           const plugin::dwarf::DWARFUnit *dwarf_cu,
+           const plugin::dwarf::DWARFUnitInterface *dwarf_cu,
            const lldb::RegisterKind reg_set, const Value *initial_value_ptr,
            const Value *object_address_ptr);
 
-  static bool ParseDWARFLocationList(const plugin::dwarf::DWARFUnit *dwarf_cu,
-                                     const DataExtractor &data,
-                                     DWARFExpressionList *loc_list);
+  static bool
+  ParseDWARFLocationList(const plugin::dwarf::DWARFUnitInterface *dwarf_cu,
+                         const DataExtractor &data,
+                         DWARFExpressionList *loc_list);
 
   bool GetExpressionData(DataExtractor &data) const {
     data = m_data;

lldb/source/Expression/DWARFExpression.cpp

@@ -133,7 +133,7 @@ static llvm::Error ReadRegisterValueAsScalar(RegisterContext *reg_ctx,
 static lldb::offset_t GetOpcodeDataSize(const DataExtractor &data,
                                         const lldb::offset_t data_offset,
                                         const LocationAtom op,
-                                        const DWARFUnit *dwarf_cu) {
+                                        const DWARFUnitInterface *dwarf_cu) {
   lldb::offset_t offset = data_offset;
   switch (op) {
   // Only used in LLVM metadata.
@@ -362,7 +362,8 @@ static lldb::offset_t GetOpcodeDataSize(const DataExtractor &data,
                                // + LEB128
   {
     data.Skip_LEB128(&offset);
-    return DWARFUnit::GetAddressByteSize(dwarf_cu) + offset - data_offset;
+    return DWARFUnitInterface::GetAddressByteSize(dwarf_cu) + offset -
+           data_offset;
   }
 
   case DW_OP_GNU_entry_value:
@@ -393,8 +394,8 @@ static lldb::offset_t GetOpcodeDataSize(const DataExtractor &data,
   return LLDB_INVALID_OFFSET;
 }
 
-llvm::Expected<lldb::addr_t>
-DWARFExpression::GetLocation_DW_OP_addr(const DWARFUnit *dwarf_cu) const {
+llvm::Expected<lldb::addr_t> DWARFExpression::GetLocation_DW_OP_addr(
+    const DWARFUnitInterface *dwarf_cu) const {
   lldb::offset_t offset = 0;
   while (m_data.ValidOffset(offset)) {
     const LocationAtom op = static_cast<LocationAtom>(m_data.GetU8(&offset));
@@ -422,7 +423,7 @@ DWARFExpression::GetLocation_DW_OP_addr(const DWARFUnit *dwarf_cu) const {
   return LLDB_INVALID_ADDRESS;
 }
 
-bool DWARFExpression::Update_DW_OP_addr(const DWARFUnit *dwarf_cu,
+bool DWARFExpression::Update_DW_OP_addr(const DWARFUnitInterface *dwarf_cu,
                                         lldb::addr_t file_addr) {
   lldb::offset_t offset = 0;
   while (m_data.ValidOffset(offset)) {
@@ -481,7 +482,7 @@ bool DWARFExpression::Update_DW_OP_addr(const DWARFUnit *dwarf_cu,
 }
 
 bool DWARFExpression::ContainsThreadLocalStorage(
-    const DWARFUnit *dwarf_cu) const {
+    const DWARFUnitInterface *dwarf_cu) const {
   lldb::offset_t offset = 0;
   while (m_data.ValidOffset(offset)) {
     const LocationAtom op = static_cast<LocationAtom>(m_data.GetU8(&offset));
@@ -497,7 +498,7 @@ bool DWARFExpression::ContainsThreadLocalStorage(
   return false;
 }
 bool DWARFExpression::LinkThreadLocalStorage(
-    const DWARFUnit *dwarf_cu,
+    const DWARFUnitInterface *dwarf_cu,
     std::function<lldb::addr_t(lldb::addr_t file_addr)> const
         &link_address_callback) {
   const uint32_t addr_byte_size = m_data.GetAddressByteSize();
@@ -783,7 +784,8 @@ enum LocationDescriptionKind {
   /* Composite*/
 };
 /// Adjust value's ValueType according to the kind of location description.
-void UpdateValueTypeFromLocationDescription(Log *log, const DWARFUnit *dwarf_cu,
+void UpdateValueTypeFromLocationDescription(Log *log,
+                                            const DWARFUnitInterface *dwarf_cu,
                                             LocationDescriptionKind kind,
                                             Value *value = nullptr) {
   // Note that this function is conflating DWARF expressions with
@@ -875,7 +877,7 @@ static Scalar DerefSizeExtractDataHelper(uint8_t *addr_bytes,
 llvm::Expected<Value> DWARFExpression::Evaluate(
     ExecutionContext *exe_ctx, RegisterContext *reg_ctx,
     lldb::ModuleSP module_sp, const DataExtractor &opcodes,
-    const DWARFUnit *dwarf_cu, const lldb::RegisterKind reg_kind,
+    const DWARFUnitInterface *dwarf_cu, const lldb::RegisterKind reg_kind,
     const Value *initial_value_ptr, const Value *object_address_ptr) {
 
   if (opcodes.GetByteSize() == 0)
@@ -2164,35 +2166,10 @@ llvm::Expected<Value> DWARFExpression::Evaluate(
         if (!bit_size)
           return llvm::createStringError("unspecified architecture");
       } else {
-        // Retrieve the type DIE that the value is being converted to. This
-        // offset is compile unit relative so we need to fix it up.
-        const uint64_t abs_die_offset = die_offset +  dwarf_cu->GetOffset();
-        // FIXME: the constness has annoying ripple effects.
-        DWARFDIE die = const_cast<DWARFUnit *>(dwarf_cu)->GetDIE(abs_die_offset);
-        if (!die)
-          return llvm::createStringError(
-              "cannot resolve DW_OP_convert type DIE");
-        uint64_t encoding =
-            die.GetAttributeValueAsUnsigned(DW_AT_encoding, DW_ATE_hi_user);
-        bit_size = die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8;
-        if (!bit_size)
-          bit_size = die.GetAttributeValueAsUnsigned(DW_AT_bit_size, 0);
-        if (!bit_size)
-          return llvm::createStringError(
-              "unsupported type size in DW_OP_convert");
-        switch (encoding) {
-        case DW_ATE_signed:
-        case DW_ATE_signed_char:
-          sign = true;
-          break;
-        case DW_ATE_unsigned:
-        case DW_ATE_unsigned_char:
-          sign = false;
-          break;
-        default:
-          return llvm::createStringError(
-              "unsupported encoding in DW_OP_convert");
-        }
+        if (llvm::Error err =
+                const_cast<DWARFUnitInterface *>(dwarf_cu)->GetBitSizeAndSign(
+                    die_offset, bit_size, sign))
+          return err;
       }
       Scalar &top = stack.back().ResolveValue(exe_ctx);
       top.TruncOrExtendTo(bit_size, sign);
@@ -2353,7 +2330,7 @@ llvm::Expected<Value> DWARFExpression::Evaluate(
 }
 
 bool DWARFExpression::ParseDWARFLocationList(
-    const DWARFUnit *dwarf_cu, const DataExtractor &data,
+    const DWARFUnitInterface *dwarf_cu, const DataExtractor &data,
     DWARFExpressionList *location_list) {
   location_list->Clear();
   std::unique_ptr<llvm::DWARFLocationTable> loctable_up =

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

@@ -44,8 +44,8 @@ bool DWARFFormValue::ExtractValue(const DWARFDataExtractor &data,
     switch (m_form) {
     case DW_FORM_addr:
       assert(m_unit);
-      m_value.uval =
-          data.GetMaxU64(offset_ptr, DWARFUnit::GetAddressByteSize(m_unit));
+      m_value.uval = data.GetMaxU64(
+          offset_ptr, DWARFUnitInterface::GetAddressByteSize(m_unit));
       break;
     case DW_FORM_block1:
       m_value.uval = data.GetU8(offset_ptr);
@@ -242,7 +242,7 @@ bool DWARFFormValue::SkipValue(dw_form_t form,
 
   // Compile unit address sized values
   case DW_FORM_addr:
-    *offset_ptr += DWARFUnit::GetAddressByteSize(unit);
+    *offset_ptr += DWARFUnitInterface::GetAddressByteSize(unit);
     return true;
 
   case DW_FORM_ref_addr:

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

@@ -672,6 +672,37 @@ DWARFUnit::GetDIE(dw_offset_t die_offset) {
   return DWARFDIE(); // Not found
 }
 
+llvm::Error DWARFUnit::GetBitSizeAndSign(uint64_t die_offset,
+                                         uint64_t &bit_size, bool &sign) {
+  // Retrieve the type DIE that the value is being converted to. This
+  // offset is compile unit relative so we need to fix it up.
+  const uint64_t abs_die_offset = die_offset + GetOffset();
+  // FIXME: the constness has annoying ripple effects.
+  DWARFDIE die = GetDIE(abs_die_offset);
+  if (!die)
+    return llvm::createStringError("cannot resolve DW_OP_convert type DIE");
+  uint64_t encoding =
+      die.GetAttributeValueAsUnsigned(DW_AT_encoding, DW_ATE_hi_user);
+  bit_size = die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8;
+  if (!bit_size)
+    bit_size = die.GetAttributeValueAsUnsigned(DW_AT_bit_size, 0);
+  if (!bit_size)
+    return llvm::createStringError("unsupported type size in DW_OP_convert");
+  switch (encoding) {
+  case DW_ATE_signed:
+  case DW_ATE_signed_char:
+    sign = true;
+    break;
+  case DW_ATE_unsigned:
+  case DW_ATE_unsigned_char:
+    sign = false;
+    break;
+  default:
+    return llvm::createStringError("unsupported encoding in DW_OP_convert");
+  }
+  return llvm::Error::success();
+}
+
 llvm::StringRef DWARFUnit::PeekDIEName(dw_offset_t die_offset) {
   DWARFDebugInfoEntry die;
   if (!die.Extract(GetData(), *this, &die_offset))
@@ -703,14 +734,6 @@ DWARFUnit &DWARFUnit::GetNonSkeletonUnit() {
   return *this;
 }
 
-uint8_t DWARFUnit::GetAddressByteSize(const DWARFUnit *cu) {
-  if (cu)
-    return cu->GetAddressByteSize();
-  return DWARFUnit::GetDefaultAddressSize();
-}
-
-uint8_t DWARFUnit::GetDefaultAddressSize() { return 4; }
-
 DWARFCompileUnit *DWARFUnit::GetSkeletonUnit() {
   if (m_skeleton_unit.load() == nullptr && IsDWOUnit()) {
     SymbolFileDWARFDwo *dwo =

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

@@ -38,7 +38,34 @@ enum DWARFProducer {
   eProducerOther
 };
 
-class DWARFUnit : public UserID {
+class DWARFUnitInterface {
+public:
+  DWARFUnitInterface() = default;
+  virtual ~DWARFUnitInterface() = default;
+
+  virtual SymbolFileDWARF &GetSymbolFileDWARF() const = 0;
+  virtual dw_addr_t ReadAddressFromDebugAddrSection(uint32_t index) const = 0;
+  virtual uint16_t GetVersion() const = 0;
+  virtual std::unique_ptr<llvm::DWARFLocationTable>
+  GetLocationTable(const DataExtractor &data) const = 0;
+  virtual dw_addr_t GetBaseAddress() const = 0;
+  virtual uint8_t GetAddressByteSize() const = 0;
+  virtual llvm::Error GetBitSizeAndSign(uint64_t die_offset, uint64_t &bit_size,
+                                        bool &sign) = 0;
+
+  static uint8_t GetAddressByteSize(const DWARFUnitInterface *cu) {
+    if (cu)
+      return cu->GetAddressByteSize();
+    return GetDefaultAddressSize();
+  }
+
+  static uint8_t GetDefaultAddressSize() { return 4; }
+
+  DWARFUnitInterface(const DWARFUnitInterface &) = delete;
+  DWARFUnitInterface &operator=(const DWARFUnitInterface &) = delete;
+};
+
+class DWARFUnit : public UserID, public DWARFUnitInterface {
   using die_iterator_range =
       llvm::iterator_range<DWARFDebugInfoEntry::collection::iterator>;
 
@@ -116,12 +143,14 @@ class DWARFUnit : public UserID {
   size_t GetDebugInfoSize() const;
   // Size of the CU data incl. header but without initial length.
   dw_offset_t GetLength() const { return m_header.getLength(); }
-  uint16_t GetVersion() const { return m_header.getVersion(); }
+  uint16_t GetVersion() const override { return m_header.getVersion(); }
   const llvm::DWARFAbbreviationDeclarationSet *GetAbbreviations() const;
   dw_offset_t GetAbbrevOffset() const;
-  uint8_t GetAddressByteSize() const { return m_header.getAddressByteSize(); }
+  uint8_t GetAddressByteSize() const override {
+    return m_header.getAddressByteSize();
+  }
   dw_addr_t GetAddrBase() const { return m_addr_base.value_or(0); }
-  dw_addr_t GetBaseAddress() const { return m_base_addr; }
+  dw_addr_t GetBaseAddress() const override { return m_base_addr; }
   dw_offset_t GetLineTableOffset();
   dw_addr_t GetRangesBase() const { return m_ranges_base; }
   dw_addr_t GetStrOffsetsBase() const { return m_str_offsets_base; }
@@ -131,7 +160,7 @@ class DWARFUnit : public UserID {
   void SetStrOffsetsBase(dw_offset_t str_offsets_base);
   virtual void BuildAddressRangeTable(DWARFDebugAranges *debug_aranges) = 0;
 
-  dw_addr_t ReadAddressFromDebugAddrSection(uint32_t index) const;
+  dw_addr_t ReadAddressFromDebugAddrSection(uint32_t index) const override;
 
   lldb::ByteOrder GetByteOrder() const;
 
@@ -145,17 +174,16 @@ class DWARFUnit : public UserID {
 
   DWARFDIE GetDIE(dw_offset_t die_offset);
 
+  llvm::Error GetBitSizeAndSign(uint64_t die_offset, uint64_t &bit_size,
+                                bool &sign) override;
+
   /// Returns the AT_Name of the DIE at `die_offset`, if it exists, without
   /// parsing the entire compile unit. An empty is string is returned upon
   /// error or if the attribute is not present.
   llvm::StringRef PeekDIEName(dw_offset_t die_offset);
 
   DWARFUnit &GetNonSkeletonUnit();
 
-  static uint8_t GetAddressByteSize(const DWARFUnit *cu);
-
-  static uint8_t GetDefaultAddressSize();
-
   lldb_private::CompileUnit *GetLLDBCompUnit() const { return m_lldb_cu; }
 
   void SetLLDBCompUnit(lldb_private::CompileUnit *cu) { m_lldb_cu = cu; }
@@ -174,7 +202,7 @@ class DWARFUnit : public UserID {
 
   bool Supports_unnamed_objc_bitfields();
 
-  SymbolFileDWARF &GetSymbolFileDWARF() const { return m_dwarf; }
+  SymbolFileDWARF &GetSymbolFileDWARF() const override { return m_dwarf; }
 
   DWARFProducer GetProducer();
 
@@ -237,7 +265,7 @@ class DWARFUnit : public UserID {
   /// Return the location table for parsing the given location list data. The
   /// format is chosen according to the unit type. Never returns null.
   std::unique_ptr<llvm::DWARFLocationTable>
-  GetLocationTable(const DataExtractor &data) const;
+  GetLocationTable(const DataExtractor &data) const override;
 
   DWARFDataExtractor GetLocationData() const;