[DWARF] - Take relocations in account when extracting ranges from .debug_ranges

I found this when investigated "Bug 32319 - .gdb_index is broken/incomplete" for LLD.

When we have object file with .debug_ranges section it may be filled with zeroes.
Relocations are exist in file to relocate this zeroes into real values later, but until that
a pair of zeroes is treated as terminator. And DWARF parser thinks there is no ranges at all
when I am trying to collect address ranges for building .gdb_index.

Solution implemented in this patch is to take relocations in account when parsing ranges.

Differential revision: https://reviews.llvm.org/D32228

llvm-svn: 301170

1 files changed, 5 insertions, 4 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index f01050c83ba..7e8d04672c0 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -222,11 +222,11 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType, bool DumpEH,
     // sizes, but for simplicity we just use the address byte size of the last
     // compile unit (there is no easy and fast way to associate address range
     // list and the compile unit it describes).
-    DataExtractor rangesData(getRangeSection(), isLittleEndian(),
+    DataExtractor rangesData(getRangeSection().Data, isLittleEndian(),
                              savedAddressByteSize);
     offset = 0;
     DWARFDebugRangeList rangeList;
-    while (rangeList.extract(rangesData, &offset))
+    while (rangeList.extract(rangesData, &offset, getRangeSection().Relocs))
       rangeList.dump(OS);
   }
 
@@ -732,7 +732,7 @@ DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
       *SectionData = data;
       if (name == "debug_ranges") {
         // FIXME: Use the other dwo range section when we emit it.
-        RangeDWOSection = data;
+        RangeDWOSection.Data = data;
       }
     } else if (name == "debug_types") {
       // Find debug_types data by section rather than name as there are
@@ -773,6 +773,7 @@ DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
         .Case("debug_loc", &LocSection.Relocs)
         .Case("debug_info.dwo", &InfoDWOSection.Relocs)
         .Case("debug_line", &LineSection.Relocs)
+        .Case("debug_ranges", &RangeSection.Relocs)
         .Case("apple_names", &AppleNamesSection.Relocs)
         .Case("apple_types", &AppleTypesSection.Relocs)
         .Case("apple_namespaces", &AppleNamespacesSection.Relocs)
@@ -855,7 +856,7 @@ StringRef *DWARFContextInMemory::MapSectionToMember(StringRef Name) {
       .Case("debug_frame", &DebugFrameSection)
       .Case("eh_frame", &EHFrameSection)
       .Case("debug_str", &StringSection)
-      .Case("debug_ranges", &RangeSection)
+      .Case("debug_ranges", &RangeSection.Data)
       .Case("debug_macinfo", &MacinfoSection)
       .Case("debug_pubnames", &PubNamesSection)
       .Case("debug_pubtypes", &PubTypesSection)