1 files changed, 28 insertions, 36 deletions

diff --git a/llvm/lib/DWARFLinker/DWARFLinker.cpp b/llvm/lib/DWARFLinker/DWARFLinker.cpp
index 298359dea9af..62b7f629f403 100644
--- a/llvm/lib/DWARFLinker/DWARFLinker.cpp
+++ b/llvm/lib/DWARFLinker/DWARFLinker.cpp
@@ -504,9 +504,14 @@ unsigned DWARFLinker::shouldKeepSubprogramDIE(
                   &DIE);
     return Flags;
   }
+  if (*LowPc > *HighPc) {
+    reportWarning("low_pc greater than high_pc. Range will be discarded.\n",
+                  File, &DIE);
+    return Flags;
+  }
 
   // Replace the debug map range with a more accurate one.
-  Ranges[*LowPc] = ObjFileAddressRange(*HighPc, MyInfo.AddrAdjust);
+  Ranges.insert({*LowPc, *HighPc}, MyInfo.AddrAdjust);
   Unit.addFunctionRange(*LowPc, *HighPc, MyInfo.AddrAdjust);
   return Flags;
 }
@@ -1575,7 +1580,7 @@ void DWARFLinker::patchRangesForUnit(const CompileUnit &Unit,
   DWARFDataExtractor RangeExtractor(OrigDwarf.getDWARFObj(),
                                     OrigDwarf.getDWARFObj().getRangesSection(),
                                     OrigDwarf.isLittleEndian(), AddressSize);
-  auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
+  Optional<std::pair<AddressRange, int64_t>> CurrRange;
   DWARFUnit &OrigUnit = Unit.getOrigUnit();
   auto OrigUnitDie = OrigUnit.getUnitDIE(false);
   uint64_t OrigLowPc =
@@ -1598,12 +1603,11 @@ void DWARFLinker::patchRangesForUnit(const CompileUnit &Unit,
     if (!Entries.empty()) {
       const DWARFDebugRangeList::RangeListEntry &First = Entries.front();
 
-      if (CurrRange == InvalidRange ||
-          First.StartAddress + OrigLowPc < CurrRange.start() ||
-          First.StartAddress + OrigLowPc >= CurrRange.stop()) {
-        CurrRange = FunctionRanges.find(First.StartAddress + OrigLowPc);
-        if (CurrRange == InvalidRange ||
-            CurrRange.start() > First.StartAddress + OrigLowPc) {
+      if (!CurrRange ||
+          !CurrRange->first.contains(First.StartAddress + OrigLowPc)) {
+        CurrRange = FunctionRanges.getRangeValueThatContains(
+            First.StartAddress + OrigLowPc);
+        if (!CurrRange) {
           reportWarning("no mapping for range.", File);
           continue;
         }
@@ -1710,7 +1714,7 @@ void DWARFLinker::patchLineTableForUnit(CompileUnit &Unit,
   // in NewRows.
   std::vector<DWARFDebugLine::Row> Seq;
   const auto &FunctionRanges = Unit.getFunctionRanges();
-  auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
+  Optional<std::pair<AddressRange, int64_t>> CurrRange;
 
   // FIXME: This logic is meant to generate exactly the same output as
   // Darwin's classic dsymutil. There is a nicer way to implement this
@@ -1729,19 +1733,14 @@ void DWARFLinker::patchLineTableForUnit(CompileUnit &Unit,
     // it is marked as end_sequence in the input (because in that
     // case, the relocation offset is accurate and that entry won't
     // serve as the start of another function).
-    if (CurrRange == InvalidRange || Row.Address.Address < CurrRange.start() ||
-        Row.Address.Address > CurrRange.stop() ||
-        (Row.Address.Address == CurrRange.stop() && !Row.EndSequence)) {
+    if (!CurrRange || !CurrRange->first.contains(Row.Address.Address) ||
+        (Row.Address.Address == CurrRange->first.end() && !Row.EndSequence)) {
       // We just stepped out of a known range. Insert a end_sequence
       // corresponding to the end of the range.
-      uint64_t StopAddress = CurrRange != InvalidRange
-                                 ? CurrRange.stop() + CurrRange.value()
-                                 : -1ULL;
-      CurrRange = FunctionRanges.find(Row.Address.Address);
-      bool CurrRangeValid =
-          CurrRange != InvalidRange && CurrRange.start() <= Row.Address.Address;
-      if (!CurrRangeValid) {
-        CurrRange = InvalidRange;
+      uint64_t StopAddress =
+          CurrRange ? CurrRange->first.end() + CurrRange->second : -1ULL;
+      CurrRange = FunctionRanges.getRangeValueThatContains(Row.Address.Address);
+      if (!CurrRange) {
         if (StopAddress != -1ULL) {
           // Try harder by looking in the Address ranges map.
           // There are corner cases where this finds a
@@ -1749,14 +1748,9 @@ void DWARFLinker::patchLineTableForUnit(CompileUnit &Unit,
           // for now do as dsymutil.
           // FIXME: Understand exactly what cases this addresses and
           // potentially remove it along with the Ranges map.
-          auto Range = Ranges.lower_bound(Row.Address.Address);
-          if (Range != Ranges.begin() && Range != Ranges.end())
-            --Range;
-
-          if (Range != Ranges.end() && Range->first <= Row.Address.Address &&
-              Range->second.HighPC >= Row.Address.Address) {
-            StopAddress = Row.Address.Address + Range->second.Offset;
-          }
+          if (Optional<std::pair<AddressRange, int64_t>> Range =
+                  Ranges.getRangeValueThatContains(Row.Address.Address))
+            StopAddress = Row.Address.Address + (*Range).second;
         }
       }
       if (StopAddress != -1ULL && !Seq.empty()) {
@@ -1772,7 +1766,7 @@ void DWARFLinker::patchLineTableForUnit(CompileUnit &Unit,
         insertLineSequence(Seq, NewRows);
       }
 
-      if (!CurrRangeValid)
+      if (!CurrRange)
         continue;
     }
 
@@ -1781,7 +1775,7 @@ void DWARFLinker::patchLineTableForUnit(CompileUnit &Unit,
       continue;
 
     // Relocate row address and add it to the current sequence.
-    Row.Address.Address += CurrRange.value();
+    Row.Address.Address += CurrRange->second;
     Seq.emplace_back(Row);
 
     if (Row.EndSequence)
@@ -1921,11 +1915,9 @@ void DWARFLinker::patchFrameInfoForObject(const DWARFFile &File,
     // the function entry point, thus we can't just lookup the address
     // in the debug map. Use the AddressInfo's range map to see if the FDE
     // describes something that we can relocate.
-    auto Range = Ranges.upper_bound(Loc);
-    if (Range != Ranges.begin())
-      --Range;
-    if (Range == Ranges.end() || Range->first > Loc ||
-        Range->second.HighPC <= Loc) {
+    Optional<std::pair<AddressRange, int64_t>> Range =
+        Ranges.getRangeValueThatContains(Loc);
+    if (!Range) {
       // The +4 is to account for the size of the InitialLength field itself.
       InputOffset = EntryOffset + InitialLength + 4;
       continue;
@@ -1953,7 +1945,7 @@ void DWARFLinker::patchFrameInfoForObject(const DWARFFile &File,
     // fields that will get reconstructed by emitFDE().
     unsigned FDERemainingBytes = InitialLength - (4 + AddrSize);
     TheDwarfEmitter->emitFDE(IteratorInserted.first->getValue(), AddrSize,
-                             Loc + Range->second.Offset,
+                             Loc + Range->second,
                              FrameData.substr(InputOffset, FDERemainingBytes));
     InputOffset += FDERemainingBytes;
   }