Revert "[DWARFYAML] Add support for referencing different abbrev tabl…

…es."

This reverts commit f7ff0ac.

This change is causing build failure.

http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/10400

llvm/include/llvm/ObjectYAML/DWARFYAML.h

@@ -21,7 +21,6 @@
 #include "llvm/ObjectYAML/YAML.h"
 #include "llvm/Support/YAMLTraits.h"
 #include <cstdint>
-#include <unordered_map>
 #include <vector>
 
 namespace llvm {
@@ -41,7 +40,6 @@ struct Abbrev {
 };
 
 struct AbbrevTable {
-  Optional<uint64_t> ID;
   std::vector<Abbrev> Table;
 };
 
@@ -112,7 +110,6 @@ struct Unit {
   uint16_t Version;
   Optional<uint8_t> AddrSize;
   llvm::dwarf::UnitType Type; // Added in DWARF 5
-  Optional<uint64_t> AbbrevTableID;
   yaml::Hex64 AbbrOffset;
   std::vector<Entry> Entries;
 };
@@ -231,10 +228,6 @@ struct Data {
   bool isEmpty() const;
 
   SetVector<StringRef> getNonEmptySectionNames() const;
-  Expected<uint64_t> getAbbrevTableIndexByID(uint64_t ID) const;
-
-private:
-  mutable std::unordered_map<uint64_t, uint64_t> AbbrevTableID2Index;
 };
 
 } // end namespace DWARFYAML

llvm/lib/ObjectYAML/DWARFEmitter.cpp

@@ -246,8 +246,7 @@ Error DWARFYAML::emitDebugGNUPubtypes(raw_ostream &OS, const Data &DI) {
                         /*IsGNUStyle=*/true);
 }
 
-static Expected<uint64_t> writeDIE(const DWARFYAML::Data &DI, uint64_t CUIndex,
-                                   uint64_t AbbrevTableID,
+static Expected<uint64_t> writeDIE(ArrayRef<DWARFYAML::AbbrevTable> AbbrevTable,
                                    const dwarf::FormParams &Params,
                                    const DWARFYAML::Entry &Entry,
                                    raw_ostream &OS, bool IsLittleEndian) {
@@ -257,15 +256,12 @@ static Expected<uint64_t> writeDIE(const DWARFYAML::Data &DI, uint64_t CUIndex,
   if (AbbrCode == 0 || Entry.Values.empty())
     return OS.tell() - EntryBegin;
 
-  Expected<uint64_t> AbbrevTableIndexOrErr =
-      DI.getAbbrevTableIndexByID(AbbrevTableID);
-  if (!AbbrevTableIndexOrErr)
-    return createStringError(errc::invalid_argument,
-                             toString(AbbrevTableIndexOrErr.takeError()) +
-                                 " for compilation unit with index " +
-                                 utostr(CUIndex));
-  ArrayRef<DWARFYAML::Abbrev> AbbrevDecls(
-      DI.DebugAbbrev[*AbbrevTableIndexOrErr].Table);
+  if (AbbrevTable.empty())
+    return createStringError(
+        errc::invalid_argument,
+        "non-empty compilation unit should have an associated abbrev table");
+
+  ArrayRef<DWARFYAML::Abbrev> AbbrevDecls(AbbrevTable[0].Table);
 
   if (AbbrCode > AbbrevDecls.size())
     return createStringError(
@@ -388,8 +384,7 @@ static Expected<uint64_t> writeDIE(const DWARFYAML::Data &DI, uint64_t CUIndex,
 }
 
 Error DWARFYAML::emitDebugInfo(raw_ostream &OS, const DWARFYAML::Data &DI) {
-  for (uint64_t I = 0; I < DI.CompileUnits.size(); ++I) {
-    const DWARFYAML::Unit &Unit = DI.CompileUnits[I];
+  for (const DWARFYAML::Unit &Unit : DI.CompileUnits) {
     uint8_t AddrSize;
     if (Unit.AddrSize)
       AddrSize = *Unit.AddrSize;
@@ -407,11 +402,9 @@ Error DWARFYAML::emitDebugInfo(raw_ostream &OS, const DWARFYAML::Data &DI) {
     std::string EntryBuffer;
     raw_string_ostream EntryBufferOS(EntryBuffer);
 
-    uint64_t AbbrevTableID = Unit.AbbrevTableID.getValueOr(I);
     for (const DWARFYAML::Entry &Entry : Unit.Entries) {
-      if (Expected<uint64_t> EntryLength =
-              writeDIE(DI, I, AbbrevTableID, Params, Entry, EntryBufferOS,
-                       DI.IsLittleEndian))
+      if (Expected<uint64_t> EntryLength = writeDIE(
+              DI.DebugAbbrev, Params, Entry, EntryBufferOS, DI.IsLittleEndian))
         Length += *EntryLength;
       else
         return EntryLength.takeError();

llvm/lib/ObjectYAML/DWARFYAML.cpp

@@ -13,8 +13,6 @@
 
 #include "llvm/ObjectYAML/DWARFYAML.h"
 #include "llvm/BinaryFormat/Dwarf.h"
-#include "llvm/Support/Errc.h"
-#include "llvm/Support/Error.h"
 
 namespace llvm {
 
@@ -55,31 +53,6 @@ SetVector<StringRef> DWARFYAML::Data::getNonEmptySectionNames() const {
   return SecNames;
 }
 
-Expected<uint64_t> DWARFYAML::Data::getAbbrevTableIndexByID(uint64_t ID) const {
-  if (AbbrevTableID2Index.empty()) {
-    for (auto &AbbrevTable : enumerate(DebugAbbrev)) {
-      // If the abbrev table's ID isn't specified, we use the index as its ID.
-      uint64_t AbbrevTableID =
-          AbbrevTable.value().ID.getValueOr(AbbrevTable.index());
-      auto It =
-          AbbrevTableID2Index.insert({AbbrevTableID, AbbrevTable.index()});
-      if (!It.second)
-        return createStringError(
-            errc::invalid_argument,
-            "the ID (%" PRIu64 ") of abbrev table with index %" PRIu64
-            " has been used by abbrev table with index %" PRIu64,
-            AbbrevTableID, AbbrevTable.index(), It.first->second);
-    }
-  }
-
-  auto It = AbbrevTableID2Index.find(ID);
-  if (It == AbbrevTableID2Index.end())
-    return createStringError(errc::invalid_argument,
-                             "cannot find abbrev table whose ID is %" PRIu64,
-                             ID);
-  return It->second;
-}
-
 namespace yaml {
 
 void MappingTraits<DWARFYAML::Data>::mapping(IO &IO, DWARFYAML::Data &DWARF) {
@@ -107,7 +80,6 @@ void MappingTraits<DWARFYAML::Data>::mapping(IO &IO, DWARFYAML::Data &DWARF) {
 
 void MappingTraits<DWARFYAML::AbbrevTable>::mapping(
     IO &IO, DWARFYAML::AbbrevTable &AbbrevTable) {
-  IO.mapOptional("ID", AbbrevTable.ID);
   IO.mapOptional("Table", AbbrevTable.Table);
 }
 
@@ -181,7 +153,6 @@ void MappingTraits<DWARFYAML::Unit>::mapping(IO &IO, DWARFYAML::Unit &Unit) {
   IO.mapRequired("Version", Unit.Version);
   if (Unit.Version >= 5)
     IO.mapRequired("UnitType", Unit.Type);
-  IO.mapOptional("AbbrevTableID", Unit.AbbrevTableID);
   IO.mapRequired("AbbrOffset", Unit.AbbrOffset);
   IO.mapOptional("AddrSize", Unit.AddrSize);
   IO.mapOptional("Entries", Unit.Entries);

llvm/lib/ObjectYAML/ELFEmitter.cpp

@@ -944,7 +944,7 @@ static bool shouldEmitDWARF(DWARFYAML::Data &DWARF, StringRef Name) {
 
 template <class ELFT>
 Expected<uint64_t> emitDWARF(typename ELFT::Shdr &SHeader, StringRef Name,
-                             DWARFYAML::Data &DWARF,
+                             const DWARFYAML::Data &DWARF,
                              ContiguousBlobAccumulator &CBA) {
   // We are unable to predict the size of debug data, so we request to write 0
   // bytes. This should always return us an output stream unless CBA is already

llvm/test/ObjectYAML/MachO/DWARF-debug_abbrev.yaml

@@ -1,7 +1,4 @@
-## a) Test that yaml2obj is able to emit the __debug_abbrev section and obj2yaml is
-## able to convert it back.
-
-# RUN: yaml2obj --docnum=1 %s | obj2yaml | FileCheck %s
+# RUN: yaml2obj %s | obj2yaml | FileCheck %s
 
 --- !mach-o
 FileHeader:      
@@ -423,69 +420,3 @@ DWARF:
 #CHECK:       Attributes:      
 #CHECK:         - Attribute:       DW_AT_type
 #CHECK:           Form:            DW_FORM_ref4
-
-## b) Test that yaml2obj emits an error message when there are non-empty compilation
-## units and multiple abbrev tables are assigned the same ID.
-
-# RUN: not yaml2obj --docnum=2 %s 2>&1 | FileCheck %s --check-prefix=ID-COLLISION
-
-# ID-COLLISION: yaml2obj: error: the ID (1) of abbrev table with index 1 has been used by abbrev table with index 0
-
---- !mach-o
-FileHeader:
-  magic:      0xFEEDFACF
-  cputype:    0x01000007
-  cpusubtype: 0x00000003
-  filetype:   0x0000000A
-  ncmds:      1
-  sizeofcmds: 232
-  flags:      0x00000000
-  reserved:   0x00000000
-LoadCommands:
-  - cmd:      LC_SEGMENT_64
-    cmdsize:  232
-    segname:  __DWARF
-    vmaddr:   0x00
-    vmsize:   0x00
-    fileoff:  0x00
-    filesize: 0x00
-    maxprot:  0
-    initprot: 0
-    nsects:   2
-    flags:    0
-    Sections:
-      - sectname:  __debug_abbrev
-        segname:   __DWARF
-        addr:      0x00
-        size:      24
-        offset:    528
-        align:     0
-        reloff:    0x00000000
-        nreloc:    0
-        flags:     0x00000000
-        reserved1: 0x00000000
-        reserved2: 0x00000000
-        reserved3: 0x00000000
-      - sectname:  __debug_info
-        segname:   __DWARF
-        addr:      0x00
-        size:      64
-        offset:    1070
-        align:     0
-        reloff:    0x00000000
-        nreloc:    0
-        flags:     0x00000000
-        reserved1: 0x00000000
-        reserved2: 0x00000000
-        reserved3: 0x00000000
-DWARF:
-  debug_abbrev:
-    - ID: 1
-    - ID: 1
-  debug_info:
-    - Version:    4
-      AbbrOffset: 0x00
-      Entries:
-        - AbbrCode: 1
-          Values:
-            - Value: 0x1234