llvm-dwarfdump: Support multiple debug_loclists contributions

Also fixing the incorrect "offset" field being computed/printed for each
location list.

llvm-svn: 374232

2 files changed, 18 insertions, 15 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index 770f129753e..ed6c2b93ce6 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -290,20 +290,24 @@ static void dumpLoclistsSection(raw_ostream &OS, DIDumpOptions DumpOpts,
                                 const MCRegisterInfo *MRI,
                                 Optional<uint64_t> DumpOffset) {
   uint64_t Offset = 0;
-  DWARFDebugLoclists Loclists;
 
-  DWARFListTableHeader Header(".debug_loclists", "locations");
-  if (Error E = Header.extract(Data, &Offset)) {
-    WithColor::error() << toString(std::move(E)) << '\n';
-    return;
-  }
+  while (Data.isValidOffset(Offset)) {
+    DWARFListTableHeader Header(".debug_loclists", "locations");
+    if (Error E = Header.extract(Data, &Offset)) {
+      WithColor::error() << toString(std::move(E)) << '\n';
+      return;
+    }
 
-  Header.dump(OS, DumpOpts);
-  DataExtractor LocData(Data.getData().drop_front(Offset),
-                        Data.isLittleEndian(), Header.getAddrSize());
+    Header.dump(OS, DumpOpts);
+    DataExtractor LocData(Data.getData(),
+                          Data.isLittleEndian(), Header.getAddrSize());
 
-  Loclists.parse(LocData, Header.getVersion());
-  Loclists.dump(OS, 0, MRI, DumpOffset);
+    DWARFDebugLoclists Loclists;
+    uint64_t EndOffset = Header.length() + Header.getHeaderOffset();
+    Loclists.parse(LocData, Offset, EndOffset, Header.getVersion());
+    Loclists.dump(OS, 0, MRI, DumpOffset);
+    Offset = EndOffset;
+  }
 }
 
 void DWARFContext::dump(
@@ -733,7 +737,7 @@ const DWARFDebugLoclists *DWARFContext::getDebugLocDWO() {
   // Use version 4. DWO does not support the DWARF v5 .debug_loclists yet and
   // that means we are parsing the new style .debug_loc (pre-standatized version
   // of the .debug_loclists).
-  LocDWO->parse(LocData, 4 /* Version */);
+  LocDWO->parse(LocData, 0, LocData.getData().size(), 4 /* Version */);
   return LocDWO.get();
 }
 
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp
index a243ed3a80b..bdafafc7a37 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp
@@ -187,12 +187,11 @@ DWARFDebugLoclists::parseOneLocationList(const DataExtractor &Data,
   return LL;
 }
 
-void DWARFDebugLoclists::parse(DataExtractor data, unsigned Version) {
+void DWARFDebugLoclists::parse(DataExtractor data, uint64_t Offset, uint64_t EndOffset, uint16_t Version) {
   IsLittleEndian = data.isLittleEndian();
   AddressSize = data.getAddressSize();
 
-  uint64_t Offset = 0;
-  while (Offset < data.getData().size()) {
+  while (Offset < EndOffset) {
     if (auto LL = parseOneLocationList(data, &Offset, Version))
       Locations.push_back(std::move(*LL));
     else {