[llvm] r247898 - Revert "Function bitcode index in Value Symbol Table and lazy reading support"

Teresa Johnson via llvm-commits llvm-commits at lists.llvm.org
Thu Sep 17 10:01:33 PDT 2015


On Thu, Sep 17, 2015 at 9:34 AM, David Blaikie <dblaikie at gmail.com> wrote:
>
>
> On Thu, Sep 17, 2015 at 9:19 AM, Teresa Johnson via llvm-commits
> <llvm-commits at lists.llvm.org> wrote:
>>
>> Author: tejohnson
>> Date: Thu Sep 17 11:19:10 2015
>> New Revision: 247898
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=247898&view=rev
>> Log:
>> Revert "Function bitcode index in Value Symbol Table and lazy reading
>> support"
>>
>> Temporarily revert to fix some buildbot issues. One is a minor issue
>> with a variable unused in NDEBUG mode. More concerning are some test
>> failures on win7 that I need to dig into.
>
>
> Thanks for summarizing the reasons for the revert! (sometimes people
> accidentally skip this step & it makes it difficult to understand/look back
> over the history, etc)
>
>>
>> This reverts commit 4e66a74543459832cfd571db42b4543580ae1d1d.
>
>
> We try to use the SVN revision numbers, rather than the git hash, as the
> authoritative reference when talking about commits (especially in commit
> messages). There's a script (llvm/utils/git-svn/git-svnrevert) to help with
> this, that will take a git hash, revert it, but produce a commit message
> that includes the svn revision instead of the git hash.

Ah, thanks for the info. Should I amend the commit message for the revert?

Teresa

>
> - Dave
>
>>
>>
>> Removed:
>>     llvm/trunk/test/Bitcode/vst-forward-declaration.ll
>> Modified:
>>     llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h
>>     llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
>>     llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp
>>     llvm/trunk/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
>>
>> Modified: llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h
>> URL:
>> http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h?rev=247898&r1=247897&r2=247898&view=diff
>>
>> ==============================================================================
>> --- llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h (original)
>> +++ llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h Thu Sep 17 11:19:10
>> 2015
>> @@ -42,10 +42,7 @@ namespace bitc {
>>
>>      TYPE_BLOCK_ID_NEW,
>>
>> -    USELIST_BLOCK_ID,
>> -
>> -    MODULE_STRTAB_BLOCK_ID,
>> -    FUNCTION_SUMMARY_BLOCK_ID
>> +    USELIST_BLOCK_ID
>>    };
>>
>>
>> @@ -76,8 +73,6 @@ namespace bitc {
>>
>>      MODULE_CODE_GCNAME      = 11,  // GCNAME: [strchr x N]
>>      MODULE_CODE_COMDAT      = 12,  // COMDAT: [selection_kind, name]
>> -
>> -    MODULE_CODE_VSTOFFSET   = 13,  // VSTOFFSET: [offset]
>>    };
>>
>>    /// PARAMATTR blocks have code for defining a parameter attribute set.
>> @@ -136,11 +131,10 @@ namespace bitc {
>>      TST_CODE_ENTRY = 1     // TST_ENTRY: [typeid, namechar x N]
>>    };
>>
>> -  // Value symbol table codes.
>> +  // The value symbol table only has one code (VST_ENTRY_CODE).
>>    enum ValueSymtabCodes {
>> -    VST_CODE_ENTRY   = 1,   // VST_ENTRY: [valueid, namechar x N]
>> -    VST_CODE_BBENTRY = 2,   // VST_BBENTRY: [bbid, namechar x N]
>> -    VST_CODE_FNENTRY = 3,   // VST_FNENTRY: [valueid, offset, namechar x
>> N]
>> +    VST_CODE_ENTRY   = 1,  // VST_ENTRY: [valid, namechar x N]
>> +    VST_CODE_BBENTRY = 2   // VST_BBENTRY: [bbid, namechar x N]
>>    };
>>
>>    enum MetadataCodes {
>>
>> Modified: llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp?rev=247898&r1=247897&r2=247898&view=diff
>>
>> ==============================================================================
>> --- llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp (original)
>> +++ llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp Thu Sep 17 11:19:10
>> 2015
>> @@ -147,7 +147,6 @@ class BitcodeReader : public GVMateriali
>>    BitstreamCursor Stream;
>>    uint64_t NextUnreadBit = 0;
>>    bool SeenValueSymbolTable = false;
>> -  unsigned VSTOffset = 0;
>>
>>    std::vector<Type*> TypeList;
>>    BitcodeReaderValueList ValueList;
>> @@ -371,9 +370,7 @@ private:
>>    std::error_code parseTypeTable();
>>    std::error_code parseTypeTableBody();
>>
>> -  ErrorOr<Value *> recordValue(SmallVectorImpl<uint64_t> &Record,
>> -                               unsigned NameIndex, Triple &TT);
>> -  std::error_code parseValueSymbolTable(unsigned Offset = 0);
>> +  std::error_code parseValueSymbolTable();
>>    std::error_code parseConstants();
>>    std::error_code rememberAndSkipFunctionBody();
>>    /// Save the positions of the Metadata blocks and skip parsing the
>> blocks.
>> @@ -1586,61 +1583,7 @@ std::error_code BitcodeReader::parseType
>>    }
>>  }
>>
>> -/// Associate a value with its name from the given index in the provided
>> record.
>> -ErrorOr<Value *> BitcodeReader::recordValue(SmallVectorImpl<uint64_t>
>> &Record,
>> -                                            unsigned NameIndex, Triple
>> &TT) {
>> -  SmallString<128> ValueName;
>> -  if (convertToString(Record, NameIndex, ValueName))
>> -    return error("Invalid record");
>> -  unsigned ValueID = Record[0];
>> -  if (ValueID >= ValueList.size() || !ValueList[ValueID])
>> -    return error("Invalid record");
>> -  Value *V = ValueList[ValueID];
>> -
>> -  V->setName(StringRef(ValueName.data(), ValueName.size()));
>> -  auto *GO = dyn_cast<GlobalObject>(V);
>> -  if (GO) {
>> -    if (GO->getComdat() == reinterpret_cast<Comdat *>(1)) {
>> -      if (TT.isOSBinFormatMachO())
>> -        GO->setComdat(nullptr);
>> -      else
>> -        GO->setComdat(TheModule->getOrInsertComdat(V->getName()));
>> -    }
>> -  }
>> -  return V;
>> -}
>> -
>> -/// Parse the value symbol table at either the current parsing location
>> or
>> -/// at the given bit offset if provided.
>> -std::error_code BitcodeReader::parseValueSymbolTable(unsigned Offset) {
>> -  uint64_t CurrentBit;
>> -  // Pass in the Offset to distinguish between calling for the
>> module-level
>> -  // VST (where we want to jump to the VST offset) and the function-level
>> -  // VST (where we don't).
>> -  if (Offset > 0) {
>> -    // Save the current parsing location so we can jump back at the end
>> -    // of the VST read.
>> -    CurrentBit = Stream.GetCurrentBitNo();
>> -    Stream.JumpToBit(Offset * 32);
>> -    BitstreamEntry Entry = Stream.advance();
>> -    assert(Entry.Kind == BitstreamEntry::SubBlock);
>> -    assert(Entry.ID == bitc::VALUE_SYMTAB_BLOCK_ID);
>> -  }
>> -
>> -  // Compute the delta between the bitcode indices in the VST (the word
>> offset
>> -  // to the word-aligned ENTER_SUBBLOCK for the function block, and that
>> -  // expected by the lazy reader. The reader's EnterSubBlock expects to
>> have
>> -  // already read the ENTER_SUBBLOCK code (size getAbbrevIDWidth) and
>> BlockID
>> -  // (size BlockIDWidth). Note that we access the stream's AbbrevID width
>> here
>> -  // just before entering the VST subblock because: 1) the EnterSubBlock
>> -  // changes the AbbrevID width; 2) the VST block is nested within the
>> same
>> -  // outer MODULE_BLOCK as the FUNCTION_BLOCKs and therefore have the
>> same
>> -  // AbbrevID width before calling EnterSubBlock; and 3) when we want to
>> -  // jump to the FUNCTION_BLOCK using this offset later, we don't want
>> -  // to rely on the stream's AbbrevID width being that of the
>> MODULE_BLOCK.
>> -  unsigned FuncBitcodeOffsetDelta =
>> -      Stream.getAbbrevIDWidth() + bitc::BlockIDWidth;
>> -
>> +std::error_code BitcodeReader::parseValueSymbolTable() {
>>    if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
>>      return error("Invalid record");
>>
>> @@ -1658,8 +1601,6 @@ std::error_code BitcodeReader::parseValu
>>      case BitstreamEntry::Error:
>>        return error("Malformed block");
>>      case BitstreamEntry::EndBlock:
>> -      if (Offset > 0)
>> -        Stream.JumpToBit(CurrentBit);
>>        return std::error_code();
>>      case BitstreamEntry::Record:
>>        // The interesting case.
>> @@ -1672,39 +1613,23 @@ std::error_code BitcodeReader::parseValu
>>      default:  // Default behavior: unknown type.
>>        break;
>>      case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
>> -      ErrorOr<Value *> ValOrErr = recordValue(Record, 1, TT);
>> -      if (std::error_code EC = ValOrErr.getError())
>> -        return EC;
>> -      ValOrErr.get();
>> -      break;
>> -    }
>> -    case bitc::VST_CODE_FNENTRY: {
>> -      // VST_FNENTRY: [valueid, offset, namechar x N]
>> -      ErrorOr<Value *> ValOrErr = recordValue(Record, 2, TT);
>> -      if (std::error_code EC = ValOrErr.getError())
>> -        return EC;
>> -      Value *V = ValOrErr.get();
>> +      if (convertToString(Record, 1, ValueName))
>> +        return error("Invalid record");
>> +      unsigned ValueID = Record[0];
>> +      if (ValueID >= ValueList.size() || !ValueList[ValueID])
>> +        return error("Invalid record");
>> +      Value *V = ValueList[ValueID];
>>
>> -      auto *GO = dyn_cast<GlobalObject>(V);
>> -      if (!GO) {
>> -        // If this is an alias, need to get the actual Function object
>> -        // it aliases, in order to set up the DeferredFunctionInfo entry
>> below.
>> -        auto *GA = dyn_cast<GlobalAlias>(V);
>> -        if (GA)
>> -          GO = GA->getBaseObject();
>> -        assert(GO);
>> -      }
>> -
>> -      uint64_t FuncWordOffset = Record[1];
>> -      Function *F = dyn_cast<Function>(GO);
>> -      assert(F);
>> -      uint64_t FuncBitOffset = FuncWordOffset * 32;
>> -      DeferredFunctionInfo[F] = FuncBitOffset + FuncBitcodeOffsetDelta;
>> -      // Set the NextUnreadBit to point to the last function block.
>> -      // Later when parsing is resumed after function materialization,
>> -      // we can simply skip that last function block.
>> -      if (FuncBitOffset > NextUnreadBit)
>> -        NextUnreadBit = FuncBitOffset;
>> +      V->setName(StringRef(ValueName.data(), ValueName.size()));
>> +      if (auto *GO = dyn_cast<GlobalObject>(V)) {
>> +        if (GO->getComdat() == reinterpret_cast<Comdat *>(1)) {
>> +          if (TT.isOSBinFormatMachO())
>> +            GO->setComdat(nullptr);
>> +          else
>> +            GO->setComdat(TheModule->getOrInsertComdat(V->getName()));
>> +        }
>> +      }
>> +      ValueName.clear();
>>        break;
>>      }
>>      case bitc::VST_CODE_BBENTRY: {
>> @@ -2927,23 +2852,9 @@ std::error_code BitcodeReader::parseModu
>>            return EC;
>>          break;
>>        case bitc::VALUE_SYMTAB_BLOCK_ID:
>> -        if (!SeenValueSymbolTable) {
>> -          // Either this is an old form VST without function index and an
>> -          // associated VST forward declaration record (which would have
>> caused
>> -          // the VST to be jumped to and parsed before it was encountered
>> -          // normally in the stream), or there were no function blocks to
>> -          // trigger an earlier parsing of the VST.
>> -          assert(VSTOffset == 0 || FunctionsWithBodies.empty());
>> -          if (std::error_code EC = parseValueSymbolTable())
>> -            return EC;
>> -          SeenValueSymbolTable = true;
>> -        } else {
>> -          // We must have had a VST forward declaration record, which
>> caused
>> -          // the parser to jump to and parse the VST earlier.
>> -          assert(VSTOffset > 0);
>> -          if (Stream.SkipBlock())
>> -            return error("Invalid record");
>> -        }
>> +        if (std::error_code EC = parseValueSymbolTable())
>> +          return EC;
>> +        SeenValueSymbolTable = true;
>>          break;
>>        case bitc::CONSTANTS_BLOCK_ID:
>>          if (std::error_code EC = parseConstants())
>> @@ -2971,32 +2882,6 @@ std::error_code BitcodeReader::parseModu
>>            SeenFirstFunctionBody = true;
>>          }
>>
>> -        if (VSTOffset > 0) {
>> -          // If we have a VST forward declaration record, make sure we
>> -          // parse the VST now if we haven't already. It is needed to
>> -          // set up the DeferredFunctionInfo vector for lazy reading.
>> -          if (!SeenValueSymbolTable) {
>> -            if (std::error_code EC =
>> -                    BitcodeReader::parseValueSymbolTable(VSTOffset))
>> -              return EC;
>> -            SeenValueSymbolTable = true;
>> -            return std::error_code();
>> -          } else {
>> -            // If we have a VST forward declaration record, but have
>> already
>> -            // parsed the VST (just above, when the first function body
>> was
>> -            // encountered here), then we are resuming the parse after
>> -            // materializing functions. The NextUnreadBit points to the
>> start
>> -            // of the last function block recorded in the VST (set when
>> -            // parsing the VST function entries). Skip it.
>> -            if (Stream.SkipBlock())
>> -              return error("Invalid record");
>> -            continue;
>> -          }
>> -        }
>> -
>> -        // Support older bitcode files that did not have the function
>> -        // index in the VST, nor a VST forward declaration record.
>> -        // Build the DeferredFunctionInfo vector on the fly.
>>          if (std::error_code EC = rememberAndSkipFunctionBody())
>>            return EC;
>>          // Suspend parsing when we reach the function bodies. Subsequent
>> @@ -3300,12 +3185,6 @@ std::error_code BitcodeReader::parseModu
>>          return error("Invalid record");
>>        ValueList.shrinkTo(Record[0]);
>>        break;
>> -    /// MODULE_CODE_VSTOFFSET: [offset]
>> -    case bitc::MODULE_CODE_VSTOFFSET:
>> -      if (Record.size() < 1)
>> -        return error("Invalid record");
>> -      VSTOffset = Record[0];
>> -      break;
>>      }
>>      Record.clear();
>>    }
>> @@ -4763,11 +4642,6 @@ std::error_code BitcodeReader::findFunct
>>      Function *F,
>>      DenseMap<Function *, uint64_t>::iterator
>> DeferredFunctionInfoIterator) {
>>    while (DeferredFunctionInfoIterator->second == 0) {
>> -    // This is the fallback handling for the old format bitcode that
>> -    // didn't contain the function index in the VST. Assert if we end up
>> -    // here for the new format (which is the only time the VSTOffset
>> would
>> -    // be non-zero).
>> -    assert(VSTOffset == 0);
>>      if (Stream.AtEndOfStream())
>>        return error("Could not find function in stream");
>>      // ParseModule will parse the next body in the stream and set its
>>
>> Modified: llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp?rev=247898&r1=247897&r2=247898&view=diff
>>
>> ==============================================================================
>> --- llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp (original)
>> +++ llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp Thu Sep 17 11:19:10
>> 2015
>> @@ -574,40 +574,10 @@ static void writeComdats(const ValueEnum
>>    }
>>  }
>>
>> -/// Write a record that will eventually hold the word offset of the
>> -/// module-level VST. For now the offset is 0, which will be backpatched
>> -/// after the real VST is written. Returns the bit offset to backpatch.
>> -static uint64_t WriteValueSymbolTableForwardDecl(const ValueSymbolTable
>> &VST,
>> -                                                 BitstreamWriter &Stream)
>> {
>> -  if (VST.empty()) return 0;
>> -
>> -  // Write a placeholder value in for the offset of the real VST,
>> -  // which is written after the function blocks so that it can include
>> -  // the offset of each function. The placeholder offset will be
>> -  // updated when the real VST is written.
>> -  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
>> -  Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_VSTOFFSET));
>> -  // Blocks are 32-bit aligned, so we can use a 32-bit word offset to
>> -  // hold the real VST offset. Must use fixed instead of VBR as we don't
>> -  // know how many VBR chunks to reserve ahead of time.
>> -  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
>> -  unsigned VSTOffsetAbbrev = Stream.EmitAbbrev(Abbv);
>> -
>> -  // Emit the placeholder
>> -  ArrayRef<unsigned> Vals = {llvm::bitc::MODULE_CODE_VSTOFFSET, 0};
>> -  Stream.EmitRecordWithAbbrev(VSTOffsetAbbrev, Vals);
>> -
>> -  // Compute and return the bit offset to the placeholder, which will be
>> -  // patched when the real VST is written. We can simply subtract the
>> 32-bit
>> -  // fixed size from the current bit number to get the location to
>> backpatch.
>> -  return Stream.GetCurrentBitNo() - 32;
>> -}
>> -
>> -/// Emit top-level description of module, including target triple, inline
>> asm,
>> -/// descriptors for global variables, and function prototype info.
>> -/// Returns the bit offset to backpatch with the location of the real
>> VST.
>> -static uint64_t WriteModuleInfo(const Module *M, const ValueEnumerator
>> &VE,
>> -                                BitstreamWriter &Stream) {
>> +// Emit top-level description of module, including target triple, inline
>> asm,
>> +// descriptors for global variables, and function prototype info.
>> +static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
>> +                            BitstreamWriter &Stream) {
>>    // Emit various pieces of data attached to a module.
>>    if (!M->getTargetTriple().empty())
>>      WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
>> @@ -767,10 +737,6 @@ static uint64_t WriteModuleInfo(const Mo
>>      Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
>>      Vals.clear();
>>    }
>> -
>> -  uint64_t VSTOffsetPlaceholder =
>> -      WriteValueSymbolTableForwardDecl(M->getValueSymbolTable(), Stream);
>> -  return VSTOffsetPlaceholder;
>>  }
>>
>>  static uint64_t GetOptimizationFlags(const Value *V) {
>> @@ -2125,119 +2091,32 @@ static StringEncoding getStringEncoding(
>>      return SE_Fixed7;
>>  }
>>
>> -/// Emit names for globals/functions etc. The VSTOffsetPlaceholder,
>> -/// BitcodeStartBit and FunctionIndex are only passed for the
>> module-level
>> -/// VST, where we are including a function bitcode index and need to
>> -/// backpatch the VST forward declaration record.
>> -static void WriteValueSymbolTable(
>> -    const ValueSymbolTable &VST, const ValueEnumerator &VE,
>> -    BitstreamWriter &Stream, uint64_t VSTOffsetPlaceholder = 0,
>> -    uint64_t BitcodeStartBit = 0,
>> -    DenseMap<const Function *, uint64_t> *FunctionIndex = nullptr) {
>> -  if (VST.empty()) {
>> -    // WriteValueSymbolTableForwardDecl should have returned early as
>> -    // well. Ensure this handling remains in sync by asserting that
>> -    // the placeholder offset is not set.
>> -    assert(VSTOffsetPlaceholder == 0);
>> -    return;
>> -  }
>> -
>> -  if (VSTOffsetPlaceholder > 0) {
>> -    // Get the offset of the VST we are writing, and backpatch it into
>> -    // the VST forward declaration record.
>> -    uint64_t VSTOffset = Stream.GetCurrentBitNo();
>> -    // The BitcodeStartBit was the stream offset of the actual bitcode
>> -    // (e.g. excluding any initial darwin header).
>> -    VSTOffset -= BitcodeStartBit;
>> -    assert((VSTOffset & 31) == 0 && "VST block not 32-bit aligned");
>> -    Stream.BackpatchWord(VSTOffsetPlaceholder, VSTOffset / 32);
>> -  }
>> -
>> +// Emit names for globals/functions etc.
>> +static void WriteValueSymbolTable(const ValueSymbolTable &VST,
>> +                                  const ValueEnumerator &VE,
>> +                                  BitstreamWriter &Stream) {
>> +  if (VST.empty()) return;
>>    Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
>>
>> -  // For the module-level VST, add abbrev Ids for the VST_CODE_FNENTRY
>> -  // records, which are not used in the per-function VSTs.
>> -  unsigned FnEntry8BitAbbrev;
>> -  unsigned FnEntry7BitAbbrev;
>> -  unsigned FnEntry6BitAbbrev;
>> -  if (VSTOffsetPlaceholder > 0) {
>> -    // 8-bit fixed-width VST_FNENTRY function strings.
>> -    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
>> -    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_FNENTRY));
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));  // value id
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));  // funcoffset
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
>> -    FnEntry8BitAbbrev = Stream.EmitAbbrev(Abbv);
>> -
>> -    // 7-bit fixed width VST_FNENTRY function strings.
>> -    Abbv = new BitCodeAbbrev();
>> -    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_FNENTRY));
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));  // value id
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));  // funcoffset
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
>> -    FnEntry7BitAbbrev = Stream.EmitAbbrev(Abbv);
>> -
>> -    // 6-bit char6 VST_FNENTRY function strings.
>> -    Abbv = new BitCodeAbbrev();
>> -    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_FNENTRY));
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));  // value id
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));  // funcoffset
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
>> -    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
>> -    FnEntry6BitAbbrev = Stream.EmitAbbrev(Abbv);
>> -  }
>> -
>>    // FIXME: Set up the abbrev, we know how many values there are!
>>    // FIXME: We know if the type names can use 7-bit ascii.
>>    SmallVector<unsigned, 64> NameVals;
>>
>>    for (const ValueName &Name : VST) {
>> +
>>      // Figure out the encoding to use for the name.
>>      StringEncoding Bits =
>>          getStringEncoding(Name.getKeyData(), Name.getKeyLength());
>>
>>      unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
>> -    NameVals.push_back(VE.getValueID(Name.getValue()));
>> -
>> -    Function *F = dyn_cast<Function>(Name.getValue());
>> -    if (!F) {
>> -      // If value is an alias, need to get the aliased base object to
>> -      // see if it is a function.
>> -      auto *GA = dyn_cast<GlobalAlias>(Name.getValue());
>> -      if (GA && GA->getBaseObject())
>> -        F = dyn_cast<Function>(GA->getBaseObject());
>> -    }
>>
>>      // VST_ENTRY:   [valueid, namechar x N]
>> -    // VST_FNENTRY: [valueid, funcoffset, namechar x N]
>>      // VST_BBENTRY: [bbid, namechar x N]
>>      unsigned Code;
>>      if (isa<BasicBlock>(Name.getValue())) {
>>        Code = bitc::VST_CODE_BBENTRY;
>>        if (Bits == SE_Char6)
>>          AbbrevToUse = VST_BBENTRY_6_ABBREV;
>> -    } else if (F && !F->isDeclaration()) {
>> -      // Must be the module-level VST, where we pass in the Index and
>> -      // have a VSTOffsetPlaceholder. The function-level VST should not
>> -      // contain any Function symbols.
>> -      assert(FunctionIndex);
>> -      assert(VSTOffsetPlaceholder > 0);
>> -
>> -      // Save the word offset of the function (from the start of the
>> -      // actual bitcode written to the stream).
>> -      assert(FunctionIndex->count(F) == 1);
>> -      uint64_t BitcodeIndex = (*FunctionIndex)[F] - BitcodeStartBit;
>> -      assert((BitcodeIndex & 31) == 0 && "function block not 32-bit
>> aligned");
>> -      NameVals.push_back(BitcodeIndex / 32);
>> -
>> -      Code = bitc::VST_CODE_FNENTRY;
>> -      AbbrevToUse = FnEntry8BitAbbrev;
>> -      if (Bits == SE_Char6)
>> -        AbbrevToUse = FnEntry6BitAbbrev;
>> -      else if (Bits == SE_Fixed7)
>> -        AbbrevToUse = FnEntry7BitAbbrev;
>>      } else {
>>        Code = bitc::VST_CODE_ENTRY;
>>        if (Bits == SE_Char6)
>> @@ -2246,6 +2125,7 @@ static void WriteValueSymbolTable(
>>          AbbrevToUse = VST_ENTRY_7_ABBREV;
>>      }
>>
>> +    NameVals.push_back(VE.getValueID(Name.getValue()));
>>      for (const char *P = Name.getKeyData(),
>>           *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
>>        NameVals.push_back((unsigned char)*P);
>> @@ -2293,13 +2173,7 @@ static void WriteUseListBlock(const Func
>>
>>  /// WriteFunction - Emit a function body to the module stream.
>>  static void WriteFunction(const Function &F, ValueEnumerator &VE,
>> -                          BitstreamWriter &Stream,
>> -                          DenseMap<const Function *, uint64_t>
>> &FunctionIndex) {
>> -  // Save the bitcode index of the start of this function block for
>> recording
>> -  // in the VST.
>> -  uint64_t BitcodeIndex = Stream.GetCurrentBitNo();
>> -  FunctionIndex[&F] = BitcodeIndex;
>> -
>> +                          BitstreamWriter &Stream) {
>>    Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
>>    VE.incorporateFunction(F);
>>
>> @@ -2547,8 +2421,7 @@ static void WriteBlockInfo(const ValueEn
>>
>>  /// WriteModule - Emit the specified module to the bitstream.
>>  static void WriteModule(const Module *M, BitstreamWriter &Stream,
>> -                        bool ShouldPreserveUseListOrder,
>> -                        uint64_t BitcodeStartBit) {
>> +                        bool ShouldPreserveUseListOrder) {
>>    Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
>>
>>    SmallVector<unsigned, 1> Vals;
>> @@ -2575,7 +2448,7 @@ static void WriteModule(const Module *M,
>>
>>    // Emit top-level description of module, including target triple,
>> inline asm,
>>    // descriptors for global variables, and function prototype info.
>> -  uint64_t VSTOffsetPlaceholder = WriteModuleInfo(M, VE, Stream);
>> +  WriteModuleInfo(M, VE, Stream);
>>
>>    // Emit constants.
>>    WriteModuleConstants(VE, Stream);
>> @@ -2586,18 +2459,17 @@ static void WriteModule(const Module *M,
>>    // Emit metadata.
>>    WriteModuleMetadataStore(M, Stream);
>>
>> +  // Emit names for globals/functions etc.
>> +  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
>> +
>>    // Emit module-level use-lists.
>>    if (VE.shouldPreserveUseListOrder())
>>      WriteUseListBlock(nullptr, VE, Stream);
>>
>>    // Emit function bodies.
>> -  DenseMap<const Function *, uint64_t> FunctionIndex;
>>    for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
>>      if (!F->isDeclaration())
>> -      WriteFunction(*F, VE, Stream, FunctionIndex);
>> -
>> -  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream,
>> -                        VSTOffsetPlaceholder, BitcodeStartBit,
>> &FunctionIndex);
>> +      WriteFunction(*F, VE, Stream);
>>
>>    Stream.ExitBlock();
>>  }
>> @@ -2688,11 +2560,6 @@ void llvm::WriteBitcodeToFile(const Modu
>>    // Emit the module into the buffer.
>>    {
>>      BitstreamWriter Stream(Buffer);
>> -    // Save the start bit of the actual bitcode, in case there is space
>> -    // saved at the start for the darwin header above. The reader stream
>> -    // will start at the bitcode, and we need the offset of the VST
>> -    // to line up.
>> -    uint64_t BitcodeStartBit = Stream.GetCurrentBitNo();
>>
>>      // Emit the file header.
>>      Stream.Emit((unsigned)'B', 8);
>> @@ -2703,7 +2570,7 @@ void llvm::WriteBitcodeToFile(const Modu
>>      Stream.Emit(0xD, 4);
>>
>>      // Emit the module.
>> -    WriteModule(M, Stream, ShouldPreserveUseListOrder, BitcodeStartBit);
>> +    WriteModule(M, Stream, ShouldPreserveUseListOrder);
>>    }
>>
>>    if (TT.isOSDarwin())
>>
>> Removed: llvm/trunk/test/Bitcode/vst-forward-declaration.ll
>> URL:
>> http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Bitcode/vst-forward-declaration.ll?rev=247897&view=auto
>>
>> ==============================================================================
>> --- llvm/trunk/test/Bitcode/vst-forward-declaration.ll (original)
>> +++ llvm/trunk/test/Bitcode/vst-forward-declaration.ll (removed)
>> @@ -1,29 +0,0 @@
>> -; RUN: llvm-as < %s | llvm-bcanalyzer -dump | FileCheck %s
>> -check-prefix=BC
>> -; Check for VST forward declaration record and VST function index
>> records.
>> -
>> -; BC: <VSTOFFSET
>> -; BC: <FNENTRY
>> -; BC: <FNENTRY
>> -
>> -; RUN: llvm-as < %s | llvm-dis | FileCheck %s
>> -; Check that this round-trips correctly.
>> -
>> -; ModuleID = '<stdin>'
>> -target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
>> -target triple = "x86_64-unknown-linux-gnu"
>> -
>> -; CHECK: define i32 @foo()
>> -
>> -; Function Attrs: nounwind uwtable
>> -define i32 @foo() #0 {
>> -entry:
>> -  ret i32 1
>> -}
>> -
>> -; CHECK: define i32 @bar(i32 %x)
>> -
>> -; Function Attrs: nounwind uwtable
>> -define i32 @bar(i32 %x) #0 {
>> -entry:
>> -  ret i32 %x
>> -}
>>
>> Modified: llvm/trunk/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp?rev=247898&r1=247897&r2=247898&view=diff
>>
>> ==============================================================================
>> --- llvm/trunk/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp (original)
>> +++ llvm/trunk/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp Thu Sep 17
>> 11:19:10 2015
>> @@ -165,7 +165,6 @@ static const char *GetCodeName(unsigned
>>        STRINGIFY_CODE(MODULE_CODE, ALIAS)
>>        STRINGIFY_CODE(MODULE_CODE, PURGEVALS)
>>        STRINGIFY_CODE(MODULE_CODE, GCNAME)
>> -      STRINGIFY_CODE(MODULE_CODE, VSTOFFSET)
>>      }
>>    case bitc::PARAMATTR_BLOCK_ID:
>>      switch (CodeID) {
>> @@ -267,7 +266,6 @@ static const char *GetCodeName(unsigned
>>      default: return nullptr;
>>      STRINGIFY_CODE(VST_CODE, ENTRY)
>>      STRINGIFY_CODE(VST_CODE, BBENTRY)
>> -    STRINGIFY_CODE(VST_CODE, FNENTRY)
>>      }
>>    case bitc::METADATA_ATTACHMENT_ID:
>>      switch(CodeID) {
>>
>>
>> _______________________________________________
>> llvm-commits mailing list
>> llvm-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>
>



-- 
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