Extend the dumping infrastructure to deal with additional

sections for debug info. These are some of the dwo sections from the
DWARF5 split debug info proposal. Update the fission-cu.ll testcase
to show what we should be able to dump more of now.

Work in progress: Ultimately the relocations will be gone for the
dwo section and the strings will be a different form (as well as
the rest of the sections will be included).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171428 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 148 insertions, 29 deletions

diff --git a/lib/DebugInfo/DWARFCompileUnit.cpp b/lib/DebugInfo/DWARFCompileUnit.cpp
index bdd65b77e4..5026723417 100644
--- a/lib/DebugInfo/DWARFCompileUnit.cpp
+++ b/lib/DebugInfo/DWARFCompileUnit.cpp
@@ -17,8 +17,7 @@ using namespace llvm;
 using namespace dwarf;
 
 DataExtractor DWARFCompileUnit::getDebugInfoExtractor() const {
-  return DataExtractor(Context.getInfoSection(),
-                       Context.isLittleEndian(), getAddressByteSize());
+  return DataExtractor(InfoSection, isLittleEndian, AddrSize);
 }
 
 bool DWARFCompileUnit::extract(DataExtractor debug_info, uint32_t *offset_ptr) {
@@ -28,7 +27,6 @@ bool DWARFCompileUnit::extract(DataExtractor debug_info, uint32_t *offset_ptr) {
 
   if (debug_info.isValidOffset(*offset_ptr)) {
     uint64_t abbrOffset;
-    const DWARFDebugAbbrev *abbr = Context.getDebugAbbrev();
     Length = debug_info.getU32(offset_ptr);
     Version = debug_info.getU16(offset_ptr);
     abbrOffset = debug_info.getU32(offset_ptr);
@@ -36,11 +34,11 @@ bool DWARFCompileUnit::extract(DataExtractor debug_info, uint32_t *offset_ptr) {
 
     bool lengthOK = debug_info.isValidOffset(getNextCompileUnitOffset()-1);
     bool versionOK = DWARFContext::isSupportedVersion(Version);
-    bool abbrOffsetOK = Context.getAbbrevSection().size() > abbrOffset;
+    bool abbrOffsetOK = AbbrevSection.size() > abbrOffset;
     bool addrSizeOK = AddrSize == 4 || AddrSize == 8;
 
-    if (lengthOK && versionOK && addrSizeOK && abbrOffsetOK && abbr != NULL) {
-      Abbrevs = abbr->getAbbreviationDeclarationSet(abbrOffset);
+    if (lengthOK && versionOK && addrSizeOK && abbrOffsetOK && Abbrev != NULL) {
+      Abbrevs = Abbrev->getAbbreviationDeclarationSet(abbrOffset);
       return true;
     }
 
@@ -79,8 +77,7 @@ bool DWARFCompileUnit::extractRangeList(uint32_t RangeListOffset,
                                         DWARFDebugRangeList &RangeList) const {
   // Require that compile unit is extracted.
   assert(DieArray.size() > 0);
-  DataExtractor RangesData(Context.getRangeSection(),
-                           Context.isLittleEndian(), AddrSize);
+  DataExtractor RangesData(RangeSection, isLittleEndian, AddrSize);
   return RangeList.extract(RangesData, &RangeListOffset);
 }
 
diff --git a/lib/DebugInfo/DWARFCompileUnit.h b/lib/DebugInfo/DWARFCompileUnit.h
index 03e28620d4..ba638dff21 100644
--- a/lib/DebugInfo/DWARFCompileUnit.h
+++ b/lib/DebugInfo/DWARFCompileUnit.h
@@ -17,11 +17,19 @@
 
 namespace llvm {
 
-class DWARFContext;
+class DWARFDebugAbbrev;
+class StringRef;
 class raw_ostream;
+typedef DenseMap<uint64_t, std::pair<uint8_t, int64_t> > RelocAddrMap;
 
 class DWARFCompileUnit {
-  DWARFContext &Context;
+  const DWARFDebugAbbrev *Abbrev;
+  StringRef InfoSection;
+  StringRef AbbrevSection;
+  StringRef RangeSection;
+  StringRef StringSection;
+  const RelocAddrMap *RelocMap;
+  bool isLittleEndian;
 
   uint32_t Offset;
   uint32_t Length;
@@ -32,11 +40,16 @@ class DWARFCompileUnit {
   // The compile unit debug information entry item.
   std::vector<DWARFDebugInfoEntryMinimal> DieArray;
 public:
-  DWARFCompileUnit(DWARFContext &context) : Context(context) {
+
+  DWARFCompileUnit(const DWARFDebugAbbrev *DA, StringRef IS, StringRef AS,
+                   StringRef RS, StringRef SS, const RelocAddrMap *M, bool LE) :
+    Abbrev(DA), InfoSection(IS), AbbrevSection(AS),
+    RangeSection(RS), StringSection(SS), RelocMap(M), isLittleEndian(LE) {
     clear();
   }
 
-  DWARFContext &getContext() const { return Context; }
+  StringRef getStringSection() const { return StringSection; }
+  const RelocAddrMap *getRelocMap() const { return RelocMap; }
   DataExtractor getDebugInfoExtractor() const;
 
   bool extract(DataExtractor debug_info, uint32_t* offset_ptr);
diff --git a/lib/DebugInfo/DWARFContext.cpp b/lib/DebugInfo/DWARFContext.cpp
index 9e67b23116..1270e6ec72 100644
--- a/lib/DebugInfo/DWARFContext.cpp
+++ b/lib/DebugInfo/DWARFContext.cpp
@@ -53,10 +53,10 @@ void DWARFContext::dump(raw_ostream &OS) {
   OS << "\n.debug_str contents:\n";
   DataExtractor strData(getStringSection(), isLittleEndian(), 0);
   offset = 0;
-  uint32_t lastOffset = 0;
+  uint32_t strOffset = 0;
   while (const char *s = strData.getCStr(&offset)) {
-    OS << format("0x%8.8x: \"%s\"\n", lastOffset, s);
-    lastOffset = offset;
+    OS << format("0x%8.8x: \"%s\"\n", strOffset, s);
+    strOffset = offset;
   }
 
   OS << "\n.debug_ranges contents:\n";
@@ -70,6 +70,22 @@ void DWARFContext::dump(raw_ostream &OS) {
   DWARFDebugRangeList rangeList;
   while (rangeList.extract(rangesData, &offset))
     rangeList.dump(OS);
+
+  OS << "\n.debug_abbrev.dwo contents:\n";
+  getDebugAbbrevDWO()->dump(OS);
+
+  OS << "\n.debug_info.dwo contents:\n";
+  for (unsigned i = 0, e = getNumDWOCompileUnits(); i != e; ++i)
+    getDWOCompileUnitAtIndex(i)->dump(OS);
+
+  OS << "\n.debug_str.dwo contents:\n";
+  DataExtractor strDWOData(getStringDWOSection(), isLittleEndian(), 0);
+  offset = 0;
+  uint32_t strDWOOffset = 0;
+  while (const char *s = strDWOData.getCStr(&offset)) {
+    OS << format("0x%8.8x: \"%s\"\n", strDWOOffset, s);
+    strDWOOffset = offset;
+  }
 }
 
 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
@@ -83,6 +99,16 @@ const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
   return Abbrev.get();
 }
 
+const DWARFDebugAbbrev *DWARFContext::getDebugAbbrevDWO() {
+  if (AbbrevDWO)
+    return AbbrevDWO.get();
+
+  DataExtractor abbrData(getAbbrevDWOSection(), isLittleEndian(), 0);
+  AbbrevDWO.reset(new DWARFDebugAbbrev());
+  AbbrevDWO->parse(abbrData);
+  return AbbrevDWO.get();
+}
+
 const DWARFDebugAranges *DWARFContext::getDebugAranges() {
   if (Aranges)
     return Aranges.get();
@@ -124,7 +150,10 @@ void DWARFContext::parseCompileUnits() {
   const DataExtractor &DIData = DataExtractor(getInfoSection(),
                                               isLittleEndian(), 0);
   while (DIData.isValidOffset(offset)) {
-    CUs.push_back(DWARFCompileUnit(*this));
+    CUs.push_back(DWARFCompileUnit(getDebugAbbrev(), getInfoSection(),
+                                   getAbbrevSection(), getRangeSection(),
+                                   getStringSection(), &infoRelocMap(),
+                                   isLittleEndian()));
     if (!CUs.back().extract(DIData, &offset)) {
       CUs.pop_back();
       break;
@@ -134,6 +163,26 @@ void DWARFContext::parseCompileUnits() {
   }
 }
 
+void DWARFContext::parseDWOCompileUnits() {
+  uint32_t offset = 0;
+  const DataExtractor &DIData = DataExtractor(getInfoDWOSection(),
+                                              isLittleEndian(), 0);
+  while (DIData.isValidOffset(offset)) {
+    DWOCUs.push_back(DWARFCompileUnit(getDebugAbbrevDWO(), getInfoDWOSection(),
+                                      getAbbrevDWOSection(),
+                                      getRangeDWOSection(),
+                                      getStringDWOSection(),
+                                      &infoDWORelocMap(),
+                                      isLittleEndian()));
+    if (!DWOCUs.back().extract(DIData, &offset)) {
+      DWOCUs.pop_back();
+      break;
+    }
+
+    offset = DWOCUs.back().getNextCompileUnitOffset();
+  }
+}
+
 namespace {
   struct OffsetComparator {
     bool operator()(const DWARFCompileUnit &LHS,
@@ -322,14 +371,28 @@ DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj) :
       ARangeSection = data;
     else if (name == "debug_str")
       StringSection = data;
-    else if (name == "debug_ranges")
+    else if (name == "debug_ranges") {
+      // FIXME: Use the other dwo range section when we emit it.
+      RangeDWOSection = data;
       RangeSection = data;
+    }
+    else if (name == "debug_info.dwo")
+      InfoDWOSection = data;
+    else if (name == "debug_abbrev.dwo")
+      AbbrevDWOSection = data;
+    else if (name == "debug_str.dwo")
+      StringDWOSection = data;
     // Any more debug info sections go here.
     else
       continue;
 
     // TODO: For now only handle relocations for the debug_info section.
-    if (name != "debug_info")
+    RelocAddrMap *Map;
+    if (name == "debug_info")
+      Map = &InfoRelocMap;
+    else if (name == "debug_info.dwo")
+      Map = &InfoDWORelocMap;
+    else
       continue;
 
     if (i->begin_relocations() != i->end_relocations()) {
@@ -372,7 +435,7 @@ DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj) :
                      << " at " << format("%p", Address)
                      << " with width " << format("%d", R.Width)
                      << "\n");
-        RelocMap[Address] = std::make_pair(R.Width, R.Value);
+        Map->insert(std::make_pair(Address, std::make_pair(R.Width, R.Value)));
       }
     }
   }
diff --git a/lib/DebugInfo/DWARFContext.h b/lib/DebugInfo/DWARFContext.h
index 24613594de..0c3eb30a64 100644
--- a/lib/DebugInfo/DWARFContext.h
+++ b/lib/DebugInfo/DWARFContext.h
@@ -30,12 +30,19 @@ class DWARFContext : public DIContext {
   OwningPtr<DWARFDebugAranges> Aranges;
   OwningPtr<DWARFDebugLine> Line;
 
+  SmallVector<DWARFCompileUnit, 1> DWOCUs;
+  OwningPtr<DWARFDebugAbbrev> AbbrevDWO;
+
   DWARFContext(DWARFContext &) LLVM_DELETED_FUNCTION;
   DWARFContext &operator=(DWARFContext &) LLVM_DELETED_FUNCTION;
 
   /// Read compile units from the debug_info section and store them in CUs.
   void parseCompileUnits();
 
+  /// Read compile units from the debug_info.dwo section and store them in
+  /// DWOCUs.
+  void parseDWOCompileUnits();
+
 public:
   DWARFContext() {}
   virtual void dump(raw_ostream &OS);
@@ -46,6 +53,14 @@ public:
       parseCompileUnits();
     return CUs.size();
   }
+
+  /// Get the number of compile units in the DWO context.
+  unsigned getNumDWOCompileUnits() {
+    if (DWOCUs.empty())
+      parseDWOCompileUnits();
+    return DWOCUs.size();
+  }
+
   /// Get the compile unit at the specified index for this compile unit.
   DWARFCompileUnit *getCompileUnitAtIndex(unsigned index) {
     if (CUs.empty())
@@ -53,9 +68,19 @@ public:
     return &CUs[index];
   }
 
+  /// Get the compile unit at the specified index for the DWO compile units.
+  DWARFCompileUnit *getDWOCompileUnitAtIndex(unsigned index) {
+    if (DWOCUs.empty())
+      parseDWOCompileUnits();
+    return &DWOCUs[index];
+  }
+
   /// Get a pointer to the parsed DebugAbbrev object.
   const DWARFDebugAbbrev *getDebugAbbrev();
 
+  /// Get a pointer to the parsed dwo abbreviations object.
+  const DWARFDebugAbbrev *getDebugAbbrevDWO();
+
   /// Get a pointer to the parsed DebugAranges object.
   const DWARFDebugAranges *getDebugAranges();
 
@@ -69,7 +94,7 @@ public:
       DILineInfoSpecifier Specifier = DILineInfoSpecifier());
 
   virtual bool isLittleEndian() const = 0;
-  virtual const RelocAddrMap &relocMap() const = 0;
+  virtual const RelocAddrMap &infoRelocMap() const = 0;
   virtual StringRef getInfoSection() = 0;
   virtual StringRef getAbbrevSection() = 0;
   virtual StringRef getARangeSection() = 0;
@@ -77,6 +102,13 @@ public:
   virtual StringRef getStringSection() = 0;
   virtual StringRef getRangeSection() = 0;
 
+  // Sections for DWARF5 split dwarf proposal.
+  virtual StringRef getInfoDWOSection() = 0;
+  virtual StringRef getAbbrevDWOSection() = 0;
+  virtual StringRef getStringDWOSection() = 0;
+  virtual StringRef getRangeDWOSection() = 0;
+  virtual const RelocAddrMap &infoDWORelocMap() const = 0;
+
   static bool isSupportedVersion(unsigned version) {
     return version == 2 || version == 3;
   }
@@ -95,23 +127,38 @@ private:
 class DWARFContextInMemory : public DWARFContext {
   virtual void anchor();
   bool IsLittleEndian;
-  RelocAddrMap RelocMap;
+  RelocAddrMap InfoRelocMap;
   StringRef InfoSection;
   StringRef AbbrevSection;
   StringRef ARangeSection;
   StringRef LineSection;
   StringRef StringSection;
   StringRef RangeSection;
+
+  // Sections for DWARF5 split dwarf proposal.
+  RelocAddrMap InfoDWORelocMap;
+  StringRef InfoDWOSection;
+  StringRef AbbrevDWOSection;
+  StringRef StringDWOSection;
+  StringRef RangeDWOSection;
+
 public:
   DWARFContextInMemory(object::ObjectFile *);
   virtual bool isLittleEndian() const { return IsLittleEndian; }
-  virtual const RelocAddrMap &relocMap() const { return RelocMap; }
+  virtual const RelocAddrMap &infoRelocMap() const { return InfoRelocMap; }
   virtual StringRef getInfoSection() { return InfoSection; }
   virtual StringRef getAbbrevSection() { return AbbrevSection; }
   virtual StringRef getARangeSection() { return ARangeSection; }
   virtual StringRef getLineSection() { return LineSection; }
   virtual StringRef getStringSection() { return StringSection; }
   virtual StringRef getRangeSection() { return RangeSection; }
+
+  // Sections for DWARF5 split dwarf proposal.
+  virtual StringRef getInfoDWOSection() { return InfoDWOSection; }
+  virtual StringRef getAbbrevDWOSection() { return AbbrevDWOSection; }
+  virtual StringRef getStringDWOSection() { return StringDWOSection; }
+  virtual StringRef getRangeDWOSection() { return RangeDWOSection; }
+  virtual const RelocAddrMap &infoDWORelocMap() const { return InfoDWORelocMap; }
 };
 
 }
diff --git a/lib/DebugInfo/DWARFDebugInfoEntry.cpp b/lib/DebugInfo/DWARFDebugInfoEntry.cpp
index ab67464453..d3e6e9e845 100644
--- a/lib/DebugInfo/DWARFDebugInfoEntry.cpp
+++ b/lib/DebugInfo/DWARFDebugInfoEntry.cpp
@@ -417,8 +417,7 @@ DWARFDebugInfoEntryMinimal::getAttributeValueAsString(
                                                      const {
   DWARFFormValue form_value;
   if (getAttributeValue(cu, attr, form_value)) {
-    DataExtractor stringExtractor(cu->getContext().getStringSection(),
-        false, 0);
+    DataExtractor stringExtractor(cu->getStringSection(), false, 0);
     return form_value.getAsCString(&stringExtractor);
   }
   return fail_value;
diff --git a/lib/DebugInfo/DWARFFormValue.cpp b/lib/DebugInfo/DWARFFormValue.cpp
index efc2d96613..1610db27d2 100644
--- a/lib/DebugInfo/DWARFFormValue.cpp
+++ b/lib/DebugInfo/DWARFFormValue.cpp
@@ -105,8 +105,8 @@ DWARFFormValue::extractValue(DataExtractor data, uint32_t *offset_ptr,
     case DW_FORM_addr:
     case DW_FORM_ref_addr: {
       RelocAddrMap::const_iterator AI
-        = cu->getContext().relocMap().find(*offset_ptr);
-      if (AI != cu->getContext().relocMap().end()) {
+        = cu->getRelocMap()->find(*offset_ptr);
+      if (AI != cu->getRelocMap()->end()) {
         const std::pair<uint8_t, int64_t> &R = AI->second;
         Value.uval = data.getUnsigned(offset_ptr, cu->getAddressByteSize()) +
                      R.second;
@@ -153,8 +153,8 @@ DWARFFormValue::extractValue(DataExtractor data, uint32_t *offset_ptr,
       break;
     case DW_FORM_strp: {
       RelocAddrMap::const_iterator AI
-        = cu->getContext().relocMap().find(*offset_ptr);
-      if (AI != cu->getContext().relocMap().end()) {
+        = cu->getRelocMap()->find(*offset_ptr);
+      if (AI != cu->getRelocMap()->end()) {
         const std::pair<uint8_t, int64_t> &R = AI->second;
         Value.uval = data.getU32(offset_ptr) + R.second;
       } else
@@ -320,7 +320,7 @@ DWARFFormValue::skipValue(uint16_t form, DataExtractor debug_info_data,
 
 void
 DWARFFormValue::dump(raw_ostream &OS, const DWARFCompileUnit *cu) const {
-  DataExtractor debug_str_data(cu->getContext().getStringSection(), true, 0);
+  DataExtractor debug_str_data(cu->getStringSection(), true, 0);
   uint64_t uvalue = getUnsigned();
   bool cu_relative_offset = false;