llvm-dwp: Include the dwo name (if available) when diagnosing duplicate CU IDs from dwp input files

If you're building dwps from other dwps, it can be hard to track down a
duplicate CU ID if it comes from two compilations of the same file in
different modes, etc. By including the .dwo path (which is hopefully
more unique than the file path) it can help track down where the
duplicates came from.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264520 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 41 insertions, 20 deletions

diff --git a/tools/llvm-dwp/llvm-dwp.cpp b/tools/llvm-dwp/llvm-dwp.cpp
index 70bad7565be..9fa22dcae3e 100644
--- a/tools/llvm-dwp/llvm-dwp.cpp
+++ b/tools/llvm-dwp/llvm-dwp.cpp
@@ -122,10 +122,19 @@ static uint32_t getCUAbbrev(StringRef Abbrev, uint64_t AbbrCode) {
 
 struct CompileUnitIdentifiers {
   uint64_t Signature = 0;
-  const char *Name = nullptr;
-  const char *DWOName = nullptr;
+  const char *Name = "";
+  const char *DWOName = "";
 };
 
+static const char *getIndexedString(uint32_t StrIndex, StringRef StrOffsets,
+                                    StringRef Str) {
+  DataExtractor StrOffsetsData(StrOffsets, true, 0);
+  uint32_t StrOffsetsOffset = 4 * StrIndex;
+  uint32_t StrOffset = StrOffsetsData.getU32(&StrOffsetsOffset);
+  DataExtractor StrData(Str, true, 0);
+  return StrData.getCStr(&StrOffset);
+}
+
 static CompileUnitIdentifiers getCUIdentifiers(StringRef Abbrev, StringRef Info,
                                                StringRef StrOffsets,
                                                StringRef Str) {
@@ -154,13 +163,12 @@ static CompileUnitIdentifiers getCUIdentifiers(StringRef Abbrev, StringRef Info,
          (Name != 0 || Form != 0)) {
     switch (Name) {
     case dwarf::DW_AT_name: {
-      auto StrIndex = InfoData.getULEB128(&Offset);
-
-      DataExtractor StrOffsetsData(StrOffsets, true, 0);
-      uint32_t StrOffsetsOffset = 4 * StrIndex;
-      uint32_t StrOffset = StrOffsetsData.getU32(&StrOffsetsOffset);
-      DataExtractor StrData(Str, true, 0);
-      ID.Name = StrData.getCStr(&StrOffset);
+      ID.Name = getIndexedString(InfoData.getULEB128(&Offset), StrOffsets, Str);
+      break;
+    }
+    case dwarf::DW_AT_GNU_dwo_name: {
+      ID.DWOName =
+          getIndexedString(InfoData.getULEB128(&Offset), StrOffsets, Str);
       break;
     }
     case dwarf::DW_AT_GNU_dwo_id:
@@ -176,6 +184,7 @@ static CompileUnitIdentifiers getCUIdentifiers(StringRef Abbrev, StringRef Info,
 struct UnitIndexEntry {
   DWARFUnitIndex::Entry::SectionContribution Contributions[8];
   std::string Name;
+  std::string DWOName;
   StringRef DWPName;
 };
 
@@ -331,6 +340,25 @@ static bool consumeCompressedDebugSectionHeader(StringRef &data,
   return true;
 }
 
+void printDuplicateError(const std::pair<uint64_t, UnitIndexEntry> &PrevE,
+                         const CompileUnitIdentifiers &ID, StringRef DWPName) {
+  errs() << "Duplicate DWO ID (" << PrevE.first << ") in '" << PrevE.second.Name
+         << '\'';
+  if (!PrevE.second.DWPName.empty()) {
+    errs() << " (from ";
+    if (!PrevE.second.DWOName.empty())
+      errs() << '\'' << PrevE.second.DWOName << "' in ";
+    errs() << "'" << PrevE.second.DWPName.str() << "')";
+  }
+  errs() << " and '" << ID.Name << '\'';
+  if (!DWPName.empty()) {
+    errs() << " (from ";
+    if (*ID.DWOName)
+      errs() << '\'' << ID.DWOName << "\' in ";
+    errs() << '\'' << DWPName << "')";
+  }
+  errs() << '\n';
+}
 static std::error_code write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
   const auto &MCOFI = *Out.getContext().getObjectFileInfo();
   MCSection *const StrSection = MCOFI.getDwarfStrDWOSection();
@@ -468,15 +496,12 @@ static std::error_code write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
             getSubsection(CurStrOffsetSection, E, DW_SECT_STR_OFFSETS),
             CurStrSection);
         if (!P.second) {
-          auto &PrevE = *P.first;
-          std::cerr << "Duplicate DWO ID (" << PrevE.first << ") in '" << PrevE.second.Name << "' ";
-          if (!PrevE.second.DWPName.empty())
-            std::cerr << "(from '" << PrevE.second.DWPName.str() << "') ";
-          std::cerr << "and '" << ID.Name << "' (from '" << Input << "')\n";
+          printDuplicateError(*P.first, ID, Input);
           return make_error_code(std::errc::invalid_argument);
         }
         auto &NewEntry = P.first->second;
         NewEntry.Name = ID.Name;
+        NewEntry.DWOName = ID.DWOName;
         NewEntry.DWPName = Input;
         for (auto Kind : CUIndex.getColumnKinds()) {
           auto &C = NewEntry.Contributions[Kind - DW_SECT_INFO];
@@ -503,15 +528,11 @@ static std::error_code write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
           AbbrevSection, InfoSection, CurStrOffsetSection, CurStrSection);
       auto P = IndexEntries.insert(std::make_pair(ID.Signature, CurEntry));
       if (!P.second) {
-        auto &E = *P.first;
-        std::cerr << "Duplicate DWO ID (" << E.first << ") in '" << ID.Name
-                  << "' ";
-        if (!E.second.DWPName.empty())
-          std::cerr << "(from '" << E.second.DWPName.str() << "') ";
-        std::cerr << "and '" << E.second.Name << "'\n";
+        printDuplicateError(*P.first, ID, "");
         return make_error_code(std::errc::invalid_argument);
       }
       P.first->second.Name = ID.Name;
+      P.first->second.DWOName = ID.DWOName;
       addAllTypes(Out, TypeIndexEntries, TypesSection, CurTypesSection,
                   CurEntry, ContributionOffsets[DW_SECT_TYPES - DW_SECT_INFO]);
     }