[ObjectYAML] [DWARF] Abstract DWARF Initial Length values

In the DWARF 4 Spec section 7.2.2, data in many DWARF sections, and some DWARF structures start with "Initial Length Values", which are a 32-bit length, and an optional 64-bit length if the 32 bit value == UINT32_MAX.

This patch abstracts the Initial Length type in YAML, and extends its use to all the DWARF structures that are supported in the DWARFYAML code that have Initial Length values.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296911 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/ObjectYAML/DWARFYAML.h b/include/llvm/ObjectYAML/DWARFYAML.h
index d031b5ac404c5164e8ac465894e82389644b6891..f287f701004001199608936ec6bf3611b81e1ff1 100644 (file)
--- a/include/llvm/ObjectYAML/DWARFYAML.h
+++ b/include/llvm/ObjectYAML/DWARFYAML.h
@@ -13,7 +13,6 @@
 ///
 //===----------------------------------------------------------------------===//
 
-
 #ifndef LLVM_OBJECTYAML_DWARFYAML_H
 #define LLVM_OBJECTYAML_DWARFYAML_H
 
@@ -23,6 +22,26 @@
 namespace llvm {
 namespace DWARFYAML {
 
+struct InitialLength {
+  uint32_t TotalLength;
+  uint64_t TotalLength64;
+
+  bool isDWARF64() const { return TotalLength == UINT32_MAX; }
+
+  uint64_t getLength() const {
+    return isDWARF64() ? TotalLength64 : TotalLength;
+  }
+
+  void setLength(uint64_t Len) {
+    if (Len >= (uint64_t)UINT32_MAX) {
+      TotalLength64 = Len;
+      TotalLength = UINT32_MAX;
+    } else {
+      TotalLength = Len;
+    }
+  }
+};
+
 struct AttributeAbbrev {
   llvm::dwarf::Attribute Attribute;
   llvm::dwarf::Form Form;
@@ -41,7 +60,7 @@ struct ARangeDescriptor {
 };
 
 struct ARange {
-  uint32_t Length;
+  InitialLength Length;
   uint16_t Version;
   uint32_t CuOffset;
   uint8_t AddrSize;
@@ -58,7 +77,7 @@ struct PubEntry {
 struct PubSection {
   PubSection() : IsGNUStyle(false) {}
 
-  uint32_t Length;
+  InitialLength Length;
   uint16_t Version;
   uint32_t UnitOffset;
   uint32_t UnitSize;
@@ -78,7 +97,7 @@ struct Entry {
 };
 
 struct Unit {
-  uint32_t Length;
+  InitialLength Length;
   uint16_t Version;
   uint32_t AbbrOffset;
   uint8_t AddrSize;
@@ -104,8 +123,7 @@ struct LineTableOpcode {
 };
 
 struct LineTable {
-  uint32_t TotalLength;
-  uint64_t TotalLength64;
+  InitialLength Length;
   uint16_t Version;
   uint64_t PrologueLength;
   uint8_t MinInstLength;
@@ -130,7 +148,7 @@ struct Data {
 
   PubSection GNUPubNames;
   PubSection GNUPubTypes;
-  
+
   std::vector<Unit> CompileUnits;
 
   std::vector<LineTable> DebugLines;
@@ -203,7 +221,7 @@ template <> struct MappingTraits<DWARFYAML::FormValue> {
 template <> struct MappingTraits<DWARFYAML::File> {
   static void mapping(IO &IO, DWARFYAML::File &File);
 };
-  
+
 template <> struct MappingTraits<DWARFYAML::LineTableOpcode> {
   static void mapping(IO &IO, DWARFYAML::LineTableOpcode &LineTableOpcode);
 };
@@ -212,6 +230,10 @@ template <> struct MappingTraits<DWARFYAML::LineTable> {
   static void mapping(IO &IO, DWARFYAML::LineTable &LineTable);
 };
 
+template <> struct MappingTraits<DWARFYAML::InitialLength> {
+  static void mapping(IO &IO, DWARFYAML::InitialLength &DWARF);
+};
+
 #define HANDLE_DW_TAG(unused, name)                                            \
   io.enumCase(value, "DW_TAG_" #name, dwarf::DW_TAG_##name);
 

diff --git a/lib/ObjectYAML/DWARFEmitter.cpp b/lib/ObjectYAML/DWARFEmitter.cpp
index 2c2d8958e5318979516e400c1cfb56fd00267fb1..69f7d368ddc8bb12d31473988badff15029c0434 100644 (file)
--- a/lib/ObjectYAML/DWARFEmitter.cpp
+++ b/lib/ObjectYAML/DWARFEmitter.cpp
@@ -50,6 +50,13 @@ static void ZeroFillBytes(raw_ostream &OS, size_t Size) {
   OS.write(reinterpret_cast<char *>(FillData.data()), Size);
 }
 
+void writeInitialLength(const DWARFYAML::InitialLength &Length, raw_ostream &OS,
+                        bool IsLittleEndian) {
+  writeInteger((uint32_t)Length.TotalLength, OS, IsLittleEndian);
+  if (Length.isDWARF64())
+    writeInteger((uint64_t)Length.TotalLength64, OS, IsLittleEndian);
+}
+
 void DWARFYAML::EmitDebugStr(raw_ostream &OS, const DWARFYAML::Data &DI) {
   for (auto Str : DI.DebugStrings) {
     OS.write(Str.data(), Str.size());
@@ -74,7 +81,7 @@ void DWARFYAML::EmitDebugAbbrev(raw_ostream &OS, const DWARFYAML::Data &DI) {
 void DWARFYAML::EmitDebugAranges(raw_ostream &OS, const DWARFYAML::Data &DI) {
   for (auto Range : DI.ARanges) {
     auto HeaderStart = OS.tell();
-    writeInteger((uint32_t)Range.Length, OS, DI.IsLittleEndian);
+    writeInitialLength(Range.Length, OS, DI.IsLittleEndian);
     writeInteger((uint16_t)Range.Version, OS, DI.IsLittleEndian);
     writeInteger((uint32_t)Range.CuOffset, OS, DI.IsLittleEndian);
     writeInteger((uint8_t)Range.AddrSize, OS, DI.IsLittleEndian);
@@ -97,7 +104,7 @@ void DWARFYAML::EmitDebugAranges(raw_ostream &OS, const DWARFYAML::Data &DI) {
 void DWARFYAML::EmitPubSection(raw_ostream &OS,
                                const DWARFYAML::PubSection &Sect,
                                bool IsLittleEndian) {
-  writeInteger((uint32_t)Sect.Length, OS, IsLittleEndian);
+  writeInitialLength(Sect.Length, OS, IsLittleEndian);
   writeInteger((uint16_t)Sect.Version, OS, IsLittleEndian);
   writeInteger((uint32_t)Sect.UnitOffset, OS, IsLittleEndian);
   writeInteger((uint32_t)Sect.UnitSize, OS, IsLittleEndian);
@@ -113,7 +120,7 @@ void DWARFYAML::EmitPubSection(raw_ostream &OS,
 void DWARFYAML::EmitDebugInfo(raw_ostream &OS, const DWARFYAML::Data &DI) {
 
   for (auto CU : DI.CompileUnits) {
-    writeInteger((uint32_t)CU.Length, OS, DI.IsLittleEndian);
+    writeInitialLength(CU.Length, OS, DI.IsLittleEndian);
     writeInteger((uint16_t)CU.Version, OS, DI.IsLittleEndian);
     writeInteger((uint32_t)CU.AbbrOffset, OS, DI.IsLittleEndian);
     writeInteger((uint8_t)CU.AddrSize, OS, DI.IsLittleEndian);
@@ -246,12 +253,8 @@ static void EmitFileEntry(raw_ostream &OS, const DWARFYAML::File &File) {
 
 void DWARFYAML::EmitDebugLine(raw_ostream &OS, const DWARFYAML::Data &DI) {
   for (const auto &LineTable : DI.DebugLines) {
-    writeInteger((uint32_t)LineTable.TotalLength, OS, DI.IsLittleEndian);
-    uint64_t SizeOfPrologueLength = 4;
-    if (LineTable.TotalLength == UINT32_MAX) {
-      writeInteger((uint64_t)LineTable.TotalLength64, OS, DI.IsLittleEndian);
-      SizeOfPrologueLength = 8;
-    }
+    writeInitialLength(LineTable.Length, OS, DI.IsLittleEndian);
+    uint64_t SizeOfPrologueLength = LineTable.Length.isDWARF64() ? 8 : 4;
     writeInteger((uint16_t)LineTable.Version, OS, DI.IsLittleEndian);
     writeVariableSizedInteger(LineTable.PrologueLength, SizeOfPrologueLength,
                               OS, DI.IsLittleEndian);

diff --git a/lib/ObjectYAML/DWARFYAML.cpp b/lib/ObjectYAML/DWARFYAML.cpp
index 014e63fe7d34063ccd3ddb51df19964d417d9fc8..f55d59aff0475dcd26df8bc5dcd662c4b610a0e2 100644 (file)
--- a/lib/ObjectYAML/DWARFYAML.cpp
+++ b/lib/ObjectYAML/DWARFYAML.cpp
@@ -144,9 +144,7 @@ void MappingTraits<DWARFYAML::LineTableOpcode>::mapping(
 
 void MappingTraits<DWARFYAML::LineTable>::mapping(
     IO &IO, DWARFYAML::LineTable &LineTable) {
-  IO.mapRequired("TotalLength", LineTable.TotalLength);
-  if (LineTable.TotalLength == UINT32_MAX)
-    IO.mapRequired("TotalLength64", LineTable.TotalLength64);
+  IO.mapRequired("Length", LineTable.Length);
   IO.mapRequired("Version", LineTable.Version);
   IO.mapRequired("PrologueLength", LineTable.PrologueLength);
   IO.mapRequired("MinInstLength", LineTable.MinInstLength);
@@ -162,6 +160,13 @@ void MappingTraits<DWARFYAML::LineTable>::mapping(
   IO.mapRequired("Opcodes", LineTable.Opcodes);
 }
 
+void MappingTraits<DWARFYAML::InitialLength>::mapping(
+    IO &IO, DWARFYAML::InitialLength &InitialLength) {
+  IO.mapRequired("TotalLength", InitialLength.TotalLength);
+  if (InitialLength.isDWARF64())
+    IO.mapRequired("TotalLength64", InitialLength.TotalLength64);
+}
+
 } // namespace llvm::yaml
 
 } // namespace llvm

diff --git a/test/ObjectYAML/MachO/DWARF-debug_aranges.yaml b/test/ObjectYAML/MachO/DWARF-debug_aranges.yaml
index 2822c94d77514ae7ba0d7d4cc0e577f52df00490..0b0421d6a09210e62f425afd7f3a4e11f59b937a 100644 (file)
--- a/test/ObjectYAML/MachO/DWARF-debug_aranges.yaml
+++ b/test/ObjectYAML/MachO/DWARF-debug_aranges.yaml
@@ -313,7 +313,8 @@ LinkEditData:
     - _main
 DWARF:           
   debug_aranges:   
-    - Length:          44
+    - Length:          
+        TotalLength:     44
       Version:         2
       CuOffset:        0
       AddrSize:        8
@@ -325,7 +326,8 @@ DWARF:
 
 #CHECK: DWARF:           
 #CHECK:   debug_aranges:   
-#CHECK:     - Length:          44
+#CHECK:     - Length:          
+#CHECK:         TotalLength:     44
 #CHECK:       Version:         2
 #CHECK:       CuOffset:        0
 #CHECK:       AddrSize:        8

diff --git a/test/ObjectYAML/MachO/DWARF-debug_info.yaml b/test/ObjectYAML/MachO/DWARF-debug_info.yaml
index b1b6b8ad19e8ce91ba441062909c108299e34ac1..0ede72bd1f419875cc638606e39ea966422bae6a 100644 (file)
--- a/test/ObjectYAML/MachO/DWARF-debug_info.yaml
+++ b/test/ObjectYAML/MachO/DWARF-debug_info.yaml
@@ -375,7 +375,8 @@ DWARF:
         - Attribute:       DW_AT_type
           Form:            DW_FORM_ref4
   debug_aranges:   
-    - Length:          44
+    - Length:          
+        TotalLength:     44
       Version:         2
       CuOffset:        0
       AddrSize:        8
@@ -384,7 +385,8 @@ DWARF:
         - Address:         0x0000000100000F50
           Length:          52
   debug_info:      
-    - Length:          117
+    - Length:          
+        TotalLength:     117
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
@@ -452,7 +454,8 @@ DWARF:
         - AbbrCode:        0x00000000
           Values:          
   debug_line:      
-    - TotalLength:     65
+    - Length:          
+        TotalLength:     65
       Version:         2
       PrologueLength:  36
       MinInstLength:   1
@@ -508,7 +511,8 @@ DWARF:
 
 #CHECK: DWARF:           
 #CHECK:   debug_info:      
-#CHECK:     - Length:          117
+#CHECK:     - Length:          
+#CHECK:         TotalLength:     117
 #CHECK:       Version:         4
 #CHECK:       AbbrOffset:      0
 #CHECK:       AddrSize:        8

diff --git a/test/ObjectYAML/MachO/DWARF-debug_line.yaml b/test/ObjectYAML/MachO/DWARF-debug_line.yaml
index c1e015839f975feceb6db900c5047053b180138c..692b50144284832d4039aefc9b9c0b3c07901640 100644 (file)
--- a/test/ObjectYAML/MachO/DWARF-debug_line.yaml
+++ b/test/ObjectYAML/MachO/DWARF-debug_line.yaml
@@ -394,7 +394,8 @@ DWARF:
         - Attribute:       DW_AT_type
           Form:            DW_FORM_ref4
   debug_aranges:   
-    - Length:          44
+    - Length:          
+        TotalLength:     44
       Version:         2
       CuOffset:        0
       AddrSize:        8
@@ -403,7 +404,8 @@ DWARF:
         - Address:         0x0000000100000F50
           Length:          52
   debug_pubnames:  
-    Length:          23
+    Length:          
+      TotalLength:     23
     Version:         2
     UnitOffset:      0
     UnitSize:        121
@@ -411,7 +413,8 @@ DWARF:
       - DieOffset:       0x0000002A
         Name:            main
   debug_pubtypes:  
-    Length:          31
+    Length:          
+      TotalLength:     31
     Version:         2
     UnitOffset:      0
     UnitSize:        121
@@ -421,7 +424,8 @@ DWARF:
       - DieOffset:       0x00000071
         Name:            char
   debug_info:      
-    - Length:          117
+    - Length:          
+        TotalLength:     117
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
@@ -489,7 +493,8 @@ DWARF:
         - AbbrCode:        0x00000000
           Values:          
   debug_line:      
-    - TotalLength:     65
+    - Length:          
+        TotalLength:     65
       Version:         2
       PrologueLength:  36
       MinInstLength:   1
@@ -542,7 +547,8 @@ DWARF:
 ...
 
 #CHECK:   debug_line:      
-#CHECK:     - TotalLength:     65
+#CHECK:     - Length:          
+#CHECK:         TotalLength:     65
 #CHECK:       Version:         2
 #CHECK:       PrologueLength:  36
 #CHECK:       MinInstLength:   1

diff --git a/test/ObjectYAML/MachO/DWARF-pubsections.yaml b/test/ObjectYAML/MachO/DWARF-pubsections.yaml
index 8535ed0b5c452862adcfccb5ee5125279f133df7..a3c05ca5b35813381c60288a680a2967b103499e 100644 (file)
--- a/test/ObjectYAML/MachO/DWARF-pubsections.yaml
+++ b/test/ObjectYAML/MachO/DWARF-pubsections.yaml
@@ -314,7 +314,8 @@ DWARF:
     - int
     - char
   debug_pubnames:  
-    Length:          23
+    Length:
+      TotalLength:       23
     Version:         2
     UnitOffset:      0
     UnitSize:        121
@@ -322,7 +323,8 @@ DWARF:
       - DieOffset:       0x0000002A
         Name:            main
   debug_pubtypes:  
-    Length:          31
+    Length:
+      TotalLength:       31
     Version:         2
     UnitOffset:      0
     UnitSize:        121
@@ -335,7 +337,8 @@ DWARF:
 
 #CHECK: DWARF:           
 #CHECK:   debug_pubnames:  
-#CHECK:     Length:          23
+#CHECK:     Length:
+#CHECK:       TotalLength:       23
 #CHECK:     Version:         2
 #CHECK:     UnitOffset:      0
 #CHECK:     UnitSize:        121
@@ -343,7 +346,8 @@ DWARF:
 #CHECK:       - DieOffset:       0x0000002A
 #CHECK:         Name:            main
 #CHECK:   debug_pubtypes:  
-#CHECK:     Length:          31
+#CHECK:     Length:
+#CHECK:       TotalLength:       31
 #CHECK:     Version:         2
 #CHECK:     UnitOffset:      0
 #CHECK:     UnitSize:        121

diff --git a/tools/obj2yaml/dwarf2yaml.cpp b/tools/obj2yaml/dwarf2yaml.cpp
index 4e320cff441a0cdc4d242d7e6a93522385c144a3..7b45f8acc3c0e05fd07c49d4d521f9ac329f5f2d 100644 (file)
--- a/tools/obj2yaml/dwarf2yaml.cpp
+++ b/tools/obj2yaml/dwarf2yaml.cpp
@@ -17,6 +17,13 @@
 
 using namespace llvm;
 
+void dumpInitialLength(DataExtractor &Data, uint32_t &Offset,
+                       DWARFYAML::InitialLength &InitialLength) {
+  InitialLength.TotalLength = Data.getU32(&Offset);
+  if (InitialLength.isDWARF64())
+    InitialLength.TotalLength64 = Data.getU64(&Offset);
+}
+
 void dumpDebugAbbrev(DWARFContextInMemory &DCtx, DWARFYAML::Data &Y) {
   auto AbbrevSetPtr = DCtx.getDebugAbbrev();
   if (AbbrevSetPtr) {
@@ -55,7 +62,7 @@ void dumpDebugARanges(DWARFContextInMemory &DCtx, DWARFYAML::Data &Y) {
 
   while (Set.extract(ArangesData, &Offset)) {
     DWARFYAML::ARange Range;
-    Range.Length = Set.getHeader().Length;
+    Range.Length.setLength(Set.getHeader().Length);
     Range.Version = Set.getHeader().Version;
     Range.CuOffset = Set.getHeader().CuOffset;
     Range.AddrSize = Set.getHeader().AddrSize;
@@ -74,11 +81,11 @@ void dumpPubSection(DWARFContextInMemory &DCtx, DWARFYAML::PubSection &Y,
                     StringRef Section) {
   DataExtractor PubSectionData(Section, DCtx.isLittleEndian(), 0);
   uint32_t Offset = 0;
-  Y.Length = PubSectionData.getU32(&Offset);
+  dumpInitialLength(PubSectionData, Offset, Y.Length);
   Y.Version = PubSectionData.getU16(&Offset);
   Y.UnitOffset = PubSectionData.getU32(&Offset);
   Y.UnitSize = PubSectionData.getU32(&Offset);
-  while (Offset < Y.Length) {
+  while (Offset < Y.Length.getLength()) {
     DWARFYAML::PubEntry NewEntry;
     NewEntry.DieOffset = PubSectionData.getU32(&Offset);
     if (Y.IsGNUStyle)
@@ -105,7 +112,7 @@ void dumpDebugPubSections(DWARFContextInMemory &DCtx, DWARFYAML::Data &Y) {
 void dumpDebugInfo(DWARFContextInMemory &DCtx, DWARFYAML::Data &Y) {
   for (const auto &CU : DCtx.compile_units()) {
     DWARFYAML::Unit NewUnit;
-    NewUnit.Length = CU->getLength();
+    NewUnit.Length.setLength(CU->getLength());
     NewUnit.Version = CU->getVersion();
     NewUnit.AbbrOffset = CU->getAbbreviations()->getOffset();
     NewUnit.AddrSize = CU->getAddressByteSize();
@@ -233,14 +240,9 @@ void dumpDebugLines(DWARFContextInMemory &DCtx, DWARFYAML::Data &Y) {
       DataExtractor LineData(DCtx.getLineSection().Data, DCtx.isLittleEndian(),
                              CU->getAddressByteSize());
       uint32_t Offset = *StmtOffset;
-      uint64_t SizeOfPrologueLength = 4;
-      DebugLines.TotalLength = LineData.getU32(&Offset);
-      uint64_t LineTableLength = DebugLines.TotalLength;
-      if (DebugLines.TotalLength == UINT32_MAX) {
-        DebugLines.TotalLength64 = LineData.getU64(&Offset);
-        LineTableLength = DebugLines.TotalLength64;
-        SizeOfPrologueLength = 8;
-      }
+      dumpInitialLength(LineData, Offset, DebugLines.Length);
+      uint64_t LineTableLength = DebugLines.Length.getLength();
+      uint64_t SizeOfPrologueLength = DebugLines.Length.isDWARF64() ? 8 : 4;
       DebugLines.Version = LineData.getU16(&Offset);
       DebugLines.PrologueLength =
           LineData.getUnsigned(&Offset, SizeOfPrologueLength);

diff --git a/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp b/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
index 90dd688d51f22f4e7feb8a5ba0185a876e46df19..b6111e71c1a25e42d7c7fdcc9733771bdb7c7111 100644 (file)
--- a/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
+++ b/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
@@ -1172,7 +1172,8 @@ TEST(DWARFDebugInfo, TestEmptyChildren) {
                          "    Children:        DW_CHILDREN_yes\n"
                          "    Attributes:\n"
                          "debug_info:\n"
-                         "  - Length:          9\n"
+                         "  - Length:\n"
+                         "      TotalLength:          9\n"
                          "    Version:         4\n"
                          "    AbbrOffset:      0\n"
                          "    AddrSize:        8\n"