Store TypeUnits in a SmallVector<DWARFUnitSection> instead of a single DWARFUnitSection.

There will be multiple TypeUnits in an unlinked object that will be extracted
from different sections. Now that we have DWARFUnitSection that is supposed
to represent an input section, we need a DWARFUnitSection<TypeUnit> per
input .debug_types section.

Once this is done, the interface is homogenous and we can move the Section
parsing code into DWARFUnitSection.

This is a respin of r218513 that got reverted because it broke some builders.
This new version features an explicit move constructor for the DWARFUnitSection
class to workaround compilers unable to generate correct C++11 default
constructors.

Reviewers: samsonov, dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5482

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218606 91177308-0d34-0410-b5e6-96231b3b80d8

lib/DebugInfo/DWARFContext.cpp

@@ -86,15 +86,17 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) {
 
   if ((DumpType == DIDT_All || DumpType == DIDT_Types) && getNumTypeUnits()) {
     OS << "\n.debug_types contents:\n";
-    for (const auto &TU : type_units())
-      TU->dump(OS);
+    for (const auto &TUS : type_unit_sections())
+      for (const auto &TU : TUS)
+        TU->dump(OS);
   }
 
   if ((DumpType == DIDT_All || DumpType == DIDT_TypesDwo) &&
       getNumDWOTypeUnits()) {
     OS << "\n.debug_types.dwo contents:\n";
-    for (const auto &DWOTU : dwo_type_units())
-      DWOTU->dump(OS);
+    for (const auto &DWOTUS : dwo_type_unit_sections())
+      for (const auto &DWOTU : DWOTUS)
+        DWOTU->dump(OS);
   }
 
   if (DumpType == DIDT_All || DumpType == DIDT_Loc) {
@@ -337,15 +339,17 @@ void DWARFContext::parseTypeUnits() {
     uint32_t offset = 0;
     const DataExtractor &DIData =
         DataExtractor(I.second.Data, isLittleEndian(), 0);
+    TUs.push_back(DWARFUnitSection<DWARFTypeUnit>());
+    auto &TUS = TUs.back();
     while (DIData.isValidOffset(offset)) {
       std::unique_ptr<DWARFTypeUnit> TU(new DWARFTypeUnit(*this,
            getDebugAbbrev(), I.second.Data, getRangeSection(),
            getStringSection(), StringRef(), getAddrSection(),
-           &I.second.Relocs, isLittleEndian(), TUs));
+           &I.second.Relocs, isLittleEndian(), TUS));
       if (!TU->extract(DIData, &offset))
         break;
-      TUs.push_back(std::move(TU));
-      offset = TUs.back()->getNextUnitOffset();
+      TUS.push_back(std::move(TU));
+      offset = TUS.back()->getNextUnitOffset();
     }
   }
 }
@@ -376,15 +380,17 @@ void DWARFContext::parseDWOTypeUnits() {
     uint32_t offset = 0;
     const DataExtractor &DIData =
         DataExtractor(I.second.Data, isLittleEndian(), 0);
+    DWOTUs.push_back(DWARFUnitSection<DWARFTypeUnit>());
+    auto &TUS = DWOTUs.back();
     while (DIData.isValidOffset(offset)) {
       std::unique_ptr<DWARFTypeUnit> TU(new DWARFTypeUnit(*this,
           getDebugAbbrevDWO(), I.second.Data, getRangeDWOSection(),
           getStringDWOSection(), getStringOffsetDWOSection(), getAddrSection(),
-          &I.second.Relocs, isLittleEndian(), DWOTUs));
+          &I.second.Relocs, isLittleEndian(), TUS));
       if (!TU->extract(DIData, &offset))
         break;
-      DWOTUs.push_back(std::move(TU));
-      offset = DWOTUs.back()->getNextUnitOffset();
+      TUS.push_back(std::move(TU));
+      offset = TUS.back()->getNextUnitOffset();
     }
   }
 }

lib/DebugInfo/DWARFContext.h

@@ -20,6 +20,7 @@
 #include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/DebugInfo/DIContext.h"
+#include <vector>
 
 namespace llvm {
 
@@ -30,7 +31,7 @@ namespace llvm {
 class DWARFContext : public DIContext {
 
   DWARFUnitSection<DWARFCompileUnit> CUs;
-  DWARFUnitSection<DWARFTypeUnit> TUs;
+  std::vector<DWARFUnitSection<DWARFTypeUnit>> TUs;
   std::unique_ptr<DWARFDebugAbbrev> Abbrev;
   std::unique_ptr<DWARFDebugLoc> Loc;
   std::unique_ptr<DWARFDebugAranges> Aranges;
@@ -38,7 +39,7 @@ class DWARFContext : public DIContext {
   std::unique_ptr<DWARFDebugFrame> DebugFrame;
 
   DWARFUnitSection<DWARFCompileUnit> DWOCUs;
-  DWARFUnitSection<DWARFTypeUnit> DWOTUs;
+  std::vector<DWARFUnitSection<DWARFTypeUnit>> DWOTUs;
   std::unique_ptr<DWARFDebugAbbrev> AbbrevDWO;
   std::unique_ptr<DWARFDebugLocDWO> LocDWO;
 
@@ -77,6 +78,7 @@ public:
 
   typedef DWARFUnitSection<DWARFCompileUnit>::iterator_range cu_iterator_range;
   typedef DWARFUnitSection<DWARFTypeUnit>::iterator_range tu_iterator_range;
+  typedef iterator_range<std::vector<DWARFUnitSection<DWARFTypeUnit>>::iterator> tu_section_iterator_range;
 
   /// Get compile units in this context.
   cu_iterator_range compile_units() {
@@ -85,9 +87,9 @@ public:
   }
 
   /// Get type units in this context.
-  tu_iterator_range type_units() {
+  tu_section_iterator_range type_unit_sections() {
     parseTypeUnits();
-    return tu_iterator_range(TUs.begin(), TUs.end());
+    return tu_section_iterator_range(TUs.begin(), TUs.end());
   }
 
   /// Get compile units in the DWO context.
@@ -97,9 +99,9 @@ public:
   }
 
   /// Get type units in the DWO context.
-  tu_iterator_range dwo_type_units() {
+  tu_section_iterator_range dwo_type_unit_sections() {
     parseDWOTypeUnits();
-    return tu_iterator_range(DWOTUs.begin(), DWOTUs.end());
+    return tu_section_iterator_range(DWOTUs.begin(), DWOTUs.end());
   }
 
   /// Get the number of compile units in this context.

lib/DebugInfo/DWARFUnit.h

@@ -53,6 +53,10 @@ class DWARFUnitSection final : public SmallVector<std::unique_ptr<UnitType>, 1>,
   };
 
 public:
+  DWARFUnitSection() {}
+  DWARFUnitSection(DWARFUnitSection &&DUS) :
+    SmallVector<std::unique_ptr<UnitType>, 1>(std::move(DUS)) {}
+
   typedef llvm::SmallVectorImpl<std::unique_ptr<UnitType>> UnitVector;
   typedef typename UnitVector::iterator iterator;
   typedef llvm::iterator_range<typename UnitVector::iterator> iterator_range;