Revert "[DWARF] Support for loclist.dwo section in llvm and llvm-dwarfdump."

This reverts commit 81b0a3284af1dcef26e56b0de9fd74002083c471.
Will Re-apply, with updated Differtial Revision, for automatic closure of
Phabricator review.

2 files changed, 8 insertions, 37 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index 012bab35460..f7b3fb495f9 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -404,14 +404,6 @@ void DWARFContext::dump(
     dumpLoclistsSection(OS, LLDumpOpts, Data, getRegisterInfo(), *Off);
   }
   if (const auto *Off =
-          shouldDump(ExplicitDWO, ".debug_loclists.dwo", DIDT_ID_DebugLoclists,
-                     DObj->getLoclistsDWOSection().Data)) {
-    DWARFDataExtractor Data(*DObj, DObj->getLoclistsDWOSection(),
-                            isLittleEndian(), 0);
-    dumpLoclistsSection(OS, LLDumpOpts, Data, getRegisterInfo(), *Off);
-  }
-
-  if (const auto *Off =
           shouldDump(ExplicitDWO, ".debug_loc.dwo", DIDT_ID_DebugLoc,
                      DObj->getLocDWOSection().Data)) {
     DWARFDataExtractor Data(*DObj, DObj->getLocDWOSection(), isLittleEndian(),
@@ -1393,7 +1385,6 @@ class DWARFObjInMemory final : public DWARFObject {
 
   DWARFSectionMap LocSection;
   DWARFSectionMap LoclistsSection;
-  DWARFSectionMap LoclistsDWOSection;
   DWARFSectionMap LineSection;
   DWARFSectionMap RangesSection;
   DWARFSectionMap RnglistsSection;
@@ -1420,7 +1411,6 @@ class DWARFObjInMemory final : public DWARFObject {
     return StringSwitch<DWARFSectionMap *>(Name)
         .Case("debug_loc", &LocSection)
         .Case("debug_loclists", &LoclistsSection)
-        .Case("debug_loclists.dwo", &LoclistsDWOSection)
         .Case("debug_line", &LineSection)
         .Case("debug_frame", &FrameSection)
         .Case("eh_frame", &EHFrameSection)
@@ -1751,9 +1741,6 @@ public:
   const DWARFSection &getRnglistsDWOSection() const override {
     return RnglistsDWOSection;
   }
-  const DWARFSection &getLoclistsDWOSection() const override {
-    return LoclistsDWOSection;
-  }
   const DWARFSection &getAddrSection() const override { return AddrSection; }
   StringRef getCUIndexSection() const override { return CUIndexSection; }
   StringRef getGdbIndexSection() const override { return GdbIndexSection; }
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
index b662e88816f..e5d33e13644 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -186,16 +186,9 @@ DWARFUnit::DWARFUnit(DWARFContext &DC, const DWARFSection &Section,
     if (auto *IndexEntry = Header.getIndexEntry())
       if (const auto *C = IndexEntry->getOffset(DW_SECT_LOC))
         Data = Data.substr(C->Offset, C->Length);
-
-    DWARFDataExtractor DWARFData =
-        Header.getVersion() >= 5
-            ? DWARFDataExtractor(Context.getDWARFObj(),
-                                 Context.getDWARFObj().getLoclistsDWOSection(),
-                                 isLittleEndian, getAddressByteSize())
-            : DWARFDataExtractor(Data, isLittleEndian, getAddressByteSize());
-    LocTable =
-        std::make_unique<DWARFDebugLoclists>(DWARFData, Header.getVersion());
-
+    LocTable = std::make_unique<DWARFDebugLoclists>(
+        DWARFDataExtractor(Data, isLittleEndian, getAddressByteSize()),
+        Header.getVersion());
   } else if (Header.getVersion() >= 5) {
     LocTable = std::make_unique<DWARFDebugLoclists>(
         DWARFDataExtractor(Context.getDWARFObj(),
@@ -509,23 +502,14 @@ Error DWARFUnit::tryExtractDIEsIfNeeded(bool CUDieOnly) {
         RangeSectionBase = RngListTable->getHeaderSize();
     }
 
-    // In a split dwarf unit, there is no DW_AT_loclists_base attribute.
-    // Setting LocSectionBase to point past the table header.
-    if (IsDWO)
-      setLocSection(&Context.getDWARFObj().getLoclistsDWOSection(),
-                    DWARFListTableHeader::getHeaderSize(Header.getFormat()));
-    else
-      setLocSection(&Context.getDWARFObj().getLoclistsSection(),
-                    toSectionOffset(UnitDie.find(DW_AT_loclists_base), 0));
+    // FIXME: add loclists.dwo support
+    setLocSection(&Context.getDWARFObj().getLoclistsSection(),
+                  toSectionOffset(UnitDie.find(DW_AT_loclists_base), 0));
 
     if (LocSection->Data.size()) {
-      if (IsDWO)
-        LoclistTableHeader.emplace(".debug_loclists.dwo", "locations");
-      else
-        LoclistTableHeader.emplace(".debug_loclists", "locations");
-
+      LoclistTableHeader.emplace(".debug_loclists", "locations");
+      uint64_t Offset = LocSectionBase;
       uint64_t HeaderSize = DWARFListTableHeader::getHeaderSize(Header.getFormat());
-      uint64_t Offset = getLocSectionBase();
       DWARFDataExtractor Data(Context.getDWARFObj(), *LocSection,
                               isLittleEndian, getAddressByteSize());
       if (Offset < HeaderSize)