C++ MDString::getString方法代码示例

std::string GCOVProfiler::mangleName(DICompileUnit CU, const char *NewStem) {
  if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
    for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
      MDNode *N = GCov->getOperand(i);
      if (N->getNumOperands() != 2) continue;
      MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
      MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1));
      if (!GCovFile || !CompileUnit) continue;
      if (CompileUnit == CU) {
        SmallString<128> Filename = GCovFile->getString();
        sys::path::replace_extension(Filename, NewStem);
        return Filename.str();
      }
    }
  }

  SmallString<128> Filename = CU.getFilename();
  sys::path::replace_extension(Filename, NewStem);
  StringRef FName = sys::path::filename(Filename);
  SmallString<128> CurPath;
  if (sys::fs::current_path(CurPath)) return FName;
  sys::path::append(CurPath, FName);
  return CurPath.str();
}

Action* IRParser::parseAction(MDNode* node){
    Value* tagValue = node->getOperand(0);
    ActionTag* tag = new ActionTag();

    if (tagValue != NULL){
        MDNode* tagArray = cast<MDNode>(tagValue);
        for (unsigned i = 0, e = tagArray->getNumOperands(); i != e; ++i) {
            MDString* tagMD = cast<MDString>(tagArray->getOperand(i));
            tag->add(tagMD->getString());
        }
    }

    Pattern* ip = parsePattern(inputs, node->getOperand(1));
    Pattern* op = parsePattern(outputs, node->getOperand(2));
    Pattern* pp = parsePattern(inputs, node->getOperand(3));

    Procedure* scheduler = parseProc(cast<MDNode>(node->getOperand(4)));
    Procedure* body = parseProc(cast<MDNode>(node->getOperand(5)));
    Action* action = new Action(tag, ip, op, pp, scheduler, body, actor);

    putAction(tag, action);

    return action;
}

/// \brief Find string metadata for loop, if it exists return true, else return
/// false.
bool llvm::findStringMetadataForLoop(Loop *TheLoop, StringRef Name) {
  MDNode *LoopID = TheLoop->getLoopID();
  // Return false if LoopID is false.
  if (!LoopID)
    return false;

  // First operand should refer to the loop id itself.
  assert(LoopID->getNumOperands() > 0 && "requires at least one operand");
  assert(LoopID->getOperand(0) == LoopID && "invalid loop id");

  // Iterate over LoopID operands and look for MDString Metadata
  for (unsigned i = 1, e = LoopID->getNumOperands(); i < e; ++i) {
    MDNode *MD = dyn_cast<MDNode>(LoopID->getOperand(i));
    if (!MD)
      continue;
    MDString *S = dyn_cast<MDString>(MD->getOperand(0));
    if (!S)
      continue;
    // Return true if MDString holds expected MetaData.
    if (Name.equals(S->getString()))
      return true;
  }
  return false;
}

/// parseMetadata - Parse metadata from the module
void LTOModule::parseMetadata() {
  // Linker Options
  if (Value *Val = getModule().getModuleFlag("Linker Options")) {
    MDNode *LinkerOptions = cast<MDNode>(Val);
    for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
      MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
      for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
        MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
        StringRef Op = _linkeropt_strings.
            GetOrCreateValue(MDOption->getString()).getKey();
        StringRef DepLibName = _target->getSubtargetImpl()
                                   ->getTargetLowering()
                                   ->getObjFileLowering()
                                   .getDepLibFromLinkerOpt(Op);
        if (!DepLibName.empty())
          _deplibs.push_back(DepLibName.data());
        else if (!Op.empty())
          _linkeropts.push_back(Op.data());
      }
    }
  }

  // Add other interesting metadata here.
}

/// emitModuleFlags - Perform code emission for module flags.
void TargetLoweringObjectFileMachO::
emitModuleFlags(MCStreamer &Streamer,
                ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
                Mangler &Mang, const TargetMachine &TM) const {
  unsigned VersionVal = 0;
  unsigned ImageInfoFlags = 0;
  MDNode *LinkerOptions = nullptr;
  StringRef SectionVal;

  for (ArrayRef<Module::ModuleFlagEntry>::iterator
         i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
    const Module::ModuleFlagEntry &MFE = *i;

    // Ignore flags with 'Require' behavior.
    if (MFE.Behavior == Module::Require)
      continue;

    StringRef Key = MFE.Key->getString();
    Value *Val = MFE.Val;

    if (Key == "Objective-C Image Info Version") {
      VersionVal = cast<ConstantInt>(Val)->getZExtValue();
    } else if (Key == "Objective-C Garbage Collection" ||
               Key == "Objective-C GC Only" ||
               Key == "Objective-C Is Simulated") {
      ImageInfoFlags |= cast<ConstantInt>(Val)->getZExtValue();
    } else if (Key == "Objective-C Image Info Section") {
      SectionVal = cast<MDString>(Val)->getString();
    } else if (Key == "Linker Options") {
      LinkerOptions = cast<MDNode>(Val);
    }
  }

  // Emit the linker options if present.
  if (LinkerOptions) {
    for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
      MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
      SmallVector<std::string, 4> StrOptions;

      // Convert to strings.
      for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
        MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
        StrOptions.push_back(MDOption->getString());
      }

      Streamer.EmitLinkerOptions(StrOptions);
    }
  }

  // The section is mandatory. If we don't have it, then we don't have GC info.
  if (SectionVal.empty()) return;

  StringRef Segment, Section;
  unsigned TAA = 0, StubSize = 0;
  bool TAAParsed;
  std::string ErrorCode =
    MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
                                          TAA, TAAParsed, StubSize);
  if (!ErrorCode.empty())
    // If invalid, report the error with report_fatal_error.
    report_fatal_error("Invalid section specifier '" + Section + "': " +
                       ErrorCode + ".");

  // Get the section.
  const MCSectionMachO *S =
    getContext().getMachOSection(Segment, Section, TAA, StubSize,
                                 SectionKind::getDataNoRel());
  Streamer.SwitchSection(S);
  Streamer.EmitLabel(getContext().
                     GetOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
  Streamer.EmitIntValue(VersionVal, 4);
  Streamer.EmitIntValue(ImageInfoFlags, 4);
  Streamer.AddBlankLine();
}

/// Merge the linker flags in Src into the Dest module.
Error IRLinker::linkModuleFlagsMetadata() {
  // If the source module has no module flags, we are done.
  const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
  if (!SrcModFlags)
    return Error::success();

  // If the destination module doesn't have module flags yet, then just copy
  // over the source module's flags.
  NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
  if (DstModFlags->getNumOperands() == 0) {
    for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
      DstModFlags->addOperand(SrcModFlags->getOperand(I));

    return Error::success();
  }

  // First build a map of the existing module flags and requirements.
  DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags;
  SmallSetVector<MDNode *, 16> Requirements;
  for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
    MDNode *Op = DstModFlags->getOperand(I);
    ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
    MDString *ID = cast<MDString>(Op->getOperand(1));

    if (Behavior->getZExtValue() == Module::Require) {
      Requirements.insert(cast<MDNode>(Op->getOperand(2)));
    } else {
      Flags[ID] = std::make_pair(Op, I);
    }
  }

  // Merge in the flags from the source module, and also collect its set of
  // requirements.
  for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
    MDNode *SrcOp = SrcModFlags->getOperand(I);
    ConstantInt *SrcBehavior =
        mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
    MDString *ID = cast<MDString>(SrcOp->getOperand(1));
    MDNode *DstOp;
    unsigned DstIndex;
    std::tie(DstOp, DstIndex) = Flags.lookup(ID);
    unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();

    // If this is a requirement, add it and continue.
    if (SrcBehaviorValue == Module::Require) {
      // If the destination module does not already have this requirement, add
      // it.
      if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
        DstModFlags->addOperand(SrcOp);
      }
      continue;
    }

    // If there is no existing flag with this ID, just add it.
    if (!DstOp) {
      Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
      DstModFlags->addOperand(SrcOp);
      continue;
    }

    // Otherwise, perform a merge.
    ConstantInt *DstBehavior =
        mdconst::extract<ConstantInt>(DstOp->getOperand(0));
    unsigned DstBehaviorValue = DstBehavior->getZExtValue();

    // If either flag has override behavior, handle it first.
    if (DstBehaviorValue == Module::Override) {
      // Diagnose inconsistent flags which both have override behavior.
      if (SrcBehaviorValue == Module::Override &&
          SrcOp->getOperand(2) != DstOp->getOperand(2))
        return stringErr("linking module flags '" + ID->getString() +
                         "': IDs have conflicting override values");
      continue;
    } else if (SrcBehaviorValue == Module::Override) {
      // Update the destination flag to that of the source.
      DstModFlags->setOperand(DstIndex, SrcOp);
      Flags[ID].first = SrcOp;
      continue;
    }

    // Diagnose inconsistent merge behavior types.
    if (SrcBehaviorValue != DstBehaviorValue)
      return stringErr("linking module flags '" + ID->getString() +
                       "': IDs have conflicting behaviors");

    auto replaceDstValue = [&](MDNode *New) {
      Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
      MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
      DstModFlags->setOperand(DstIndex, Flag);
      Flags[ID].first = Flag;
    };

    // Perform the merge for standard behavior types.
    switch (SrcBehaviorValue) {
    case Module::Require:
    case Module::Override:
      llvm_unreachable("not possible");
    case Module::Error: {
      // Emit an error if the values differ.
//.........这里部分代码省略.........

//.........这里部分代码省略.........
      MCSymbol *BeginLabel = LandingPad->BeginLabels[j];
      assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
      PadRange P = { i, j };
      PadMap[BeginLabel] = P;
    }
  }

  // Compute the call-site table.
  SmallVector<MonoCallSiteEntry, 64> CallSites;

  MCSymbol *LastLabel = 0;
  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
        I != E; ++I) {
    for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
          MI != E; ++MI) {
      if (!MI->isLabel()) {
        continue;
      }

      MCSymbol *BeginLabel = MI->getOperand(0).getMCSymbol();
      assert(BeginLabel && "Invalid label!");

      RangeMapType::iterator L = PadMap.find(BeginLabel);

      if (L == PadMap.end())
        continue;

      PadRange P = L->second;
      const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];

      assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
              "Inconsistent landing pad map!");

      // Mono emits one landing pad for each CLR exception clause,
      // and the type info contains the clause index
      assert (LandingPad->TypeIds.size() == 1);
      assert (LandingPad->LandingPadLabel);

      LastLabel = LandingPad->EndLabels[P.RangeIndex];
      MonoCallSiteEntry Site = {BeginLabel, LastLabel,
							LandingPad->LandingPadLabel, LandingPad->TypeIds [0]};

      assert(Site.BeginLabel && Site.EndLabel && Site.PadLabel &&
              "Invalid landing pad!");

	  // FIXME: This doesn't work because it includes ranges outside clauses
#if 0
      // Try to merge with the previous call-site.
      if (CallSites.size()) {
        MonoCallSiteEntry &Prev = CallSites.back();
        if (Site.PadLabel == Prev.PadLabel && Site.TypeID == Prev.TypeID) {
          // Extend the range of the previous entry.
          Prev.EndLabel = Site.EndLabel;
          continue;
        }
      }
#endif

      // Otherwise, create a new call-site.
      CallSites.push_back(Site);
    }
  }

  //
  // Compute a mapping from method names to their AOT method index
  //
  if (FuncIndexes.size () == 0) {
    const Module *m = MMI->getModule ();
    NamedMDNode *indexes = m->getNamedMetadata ("mono.function_indexes");
	if (indexes) {
      for (unsigned int i = 0; i < indexes->getNumOperands (); ++i) {
        MDNode *n = indexes->getOperand (i);
        MDString *s = (MDString*)n->getOperand (0);
        ConstantInt *idx = (ConstantInt*)n->getOperand (1);
        FuncIndexes.GetOrCreateValue (s->getString (), (int)idx->getLimitedValue () + 1);
      }
    }
  }

  MonoEHFrameInfo *MonoEH = &EHFrameInfo->MonoEH;

  // Save information for EmitMonoLSDA
  MonoEH->MF = Asm->MF;
  MonoEH->FunctionNumber = Asm->getFunctionNumber();
  MonoEH->CallSites.insert(MonoEH->CallSites.begin(), CallSites.begin(), CallSites.end());
  MonoEH->TypeInfos = TypeInfos;
  MonoEH->PadInfos = PadInfos;
  MonoEH->MonoMethodIdx = FuncIndexes.lookup (Asm->MF->getFunction ()->getName ()) - 1;
  //outs()<<"A:"<<Asm->MF->getFunction()->getName() << " " << MonoEH->MonoMethodIdx << "\n";

  int ThisSlot = Asm->MF->getMonoInfo()->getThisStackSlot();

  if (ThisSlot != -1) {
    unsigned FrameReg;
    MonoEH->ThisOffset = Asm->MF->getTarget ().getSubtargetImpl ()->getFrameLowering ()->getFrameIndexReference (*Asm->MF, ThisSlot, FrameReg);
    MonoEH->FrameReg = Asm->MF->getTarget ().getSubtargetImpl ()->getRegisterInfo ()->getDwarfRegNum (FrameReg, true);
  } else {
    MonoEH->FrameReg = -1;
  }
}

/// linkModuleFlagsMetadata - Merge the linker flags in Src into the Dest
/// module.
bool ModuleLinker::linkModuleFlagsMetadata() {
  const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
  if (!SrcModFlags) return false;

  NamedMDNode *DstModFlags = DstM->getOrInsertModuleFlagsMetadata();

  // If the destination module doesn't have module flags yet, then just copy
  // over the source module's flags.
  if (DstModFlags->getNumOperands() == 0) {
    for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
      DstModFlags->addOperand(SrcModFlags->getOperand(I));

    return false;
  }

  bool HasErr = false;

  // Otherwise, we have to merge them based on their behaviors. First,
  // categorize all of the nodes in the modules' module flags. If an error or
  // warning occurs, then emit the appropriate message(s).
  DenseMap<MDString*, MDNode*> ErrorNode;
  DenseMap<MDString*, MDNode*> WarningNode;
  DenseMap<MDString*, MDNode*> OverrideNode;
  DenseMap<MDString*, SmallSetVector<MDNode*, 8> > RequireNodes;
  SmallSetVector<MDString*, 16> SeenIDs;

  HasErr |= categorizeModuleFlagNodes(SrcModFlags, ErrorNode, WarningNode,
                                      OverrideNode, RequireNodes, SeenIDs);
  HasErr |= categorizeModuleFlagNodes(DstModFlags, ErrorNode, WarningNode,
                                      OverrideNode, RequireNodes, SeenIDs);

  // Check that there isn't both an error and warning node for a flag.
  for (SmallSetVector<MDString*, 16>::iterator
         I = SeenIDs.begin(), E = SeenIDs.end(); I != E; ++I) {
    MDString *ID = *I;
    if (ErrorNode[ID] && WarningNode[ID])
      HasErr = emitError("linking module flags '" + ID->getString() +
                         "': IDs have conflicting behaviors");
  }

  // Early exit if we had an error.
  if (HasErr) return true;

  // Get the destination's module flags ready for new operands.
  DstModFlags->dropAllReferences();

  // Add all of the module flags to the destination module.
  DenseMap<MDString*, SmallVector<MDNode*, 4> > AddedNodes;
  for (SmallSetVector<MDString*, 16>::iterator
         I = SeenIDs.begin(), E = SeenIDs.end(); I != E; ++I) {
    MDString *ID = *I;
    if (OverrideNode[ID]) {
      DstModFlags->addOperand(OverrideNode[ID]);
      AddedNodes[ID].push_back(OverrideNode[ID]);
    } else if (ErrorNode[ID]) {
      DstModFlags->addOperand(ErrorNode[ID]);
      AddedNodes[ID].push_back(ErrorNode[ID]);
    } else if (WarningNode[ID]) {
      DstModFlags->addOperand(WarningNode[ID]);
      AddedNodes[ID].push_back(WarningNode[ID]);
    }

    for (SmallSetVector<MDNode*, 8>::iterator
           II = RequireNodes[ID].begin(), IE = RequireNodes[ID].end();
         II != IE; ++II)
      DstModFlags->addOperand(*II);
  }

  // Now check that all of the requirements have been satisfied.
  for (SmallSetVector<MDString*, 16>::iterator
         I = SeenIDs.begin(), E = SeenIDs.end(); I != E; ++I) {
    MDString *ID = *I;
    SmallSetVector<MDNode*, 8> &Set = RequireNodes[ID];

    for (SmallSetVector<MDNode*, 8>::iterator
           II = Set.begin(), IE = Set.end(); II != IE; ++II) {
      MDNode *Node = *II;
      assert(isa<MDNode>(Node->getOperand(2)) &&
             "Module flag's third operand must be an MDNode!");
      MDNode *Val = cast<MDNode>(Node->getOperand(2));

      MDString *ReqID = cast<MDString>(Val->getOperand(0));
      Value *ReqVal = Val->getOperand(1);

      bool HasValue = false;
      for (SmallVectorImpl<MDNode*>::iterator
             RI = AddedNodes[ReqID].begin(), RE = AddedNodes[ReqID].end();
           RI != RE; ++RI) {
        MDNode *ReqNode = *RI;
        if (ReqNode->getOperand(2) == ReqVal) {
          HasValue = true;
          break;
        }
      }

      if (!HasValue)
        HasErr = emitError("linking module flags '" + ReqID->getString() +
                           "': does not have the required value");
//.........这里部分代码省略.........

std::vector<SDBuildCHA::nmd_t>
SDBuildCHA::extractMetadata(NamedMDNode* md) {
  std::set<vtbl_name_t> classes;
  std::vector<SDBuildCHA::nmd_t> infoVec;

  unsigned op = 0;

  do {
    SDBuildCHA::nmd_t info;
    MDString* infoMDstr = dyn_cast_or_null<MDString>(md->getOperand(op++)->getOperand(0));
    assert(infoMDstr);
    info.className = infoMDstr->getString().str();
    GlobalVariable* classVtbl = sd_mdnodeToGV(md->getOperand(op++));

    if (classVtbl) {
      info.className = classVtbl->getName();
    }

    unsigned numOperands = sd_getNumberFromMDTuple(md->getOperand(op++)->getOperand(0));

    for (unsigned i = op; i < op + numOperands; ++i) {
      SDBuildCHA::nmd_sub_t subInfo;
      llvm::MDTuple* tup = dyn_cast<llvm::MDTuple>(md->getOperand(i));
      assert(tup);
      assert(tup->getNumOperands() == 5);

      subInfo.order = sd_getNumberFromMDTuple(tup->getOperand(0));
      subInfo.start = sd_getNumberFromMDTuple(tup->getOperand(1));
      subInfo.end = sd_getNumberFromMDTuple(tup->getOperand(2));
      subInfo.addressPoint = sd_getNumberFromMDTuple(tup->getOperand(3));
      llvm::MDTuple* parentsTup = dyn_cast<llvm::MDTuple>(tup->getOperand(4));

      unsigned numParents = sd_getNumberFromMDTuple(parentsTup->getOperand(0));
      for (int j = 0; j < numParents; j++) {
        vtbl_name_t ptName = sd_getStringFromMDTuple(parentsTup->getOperand(1+j*3));
        unsigned ptIdx = sd_getNumberFromMDTuple(parentsTup->getOperand(1+j*3+1));
        GlobalVariable* parentVtable = sd_mdnodeToGV(parentsTup->getOperand(1+j*3+2).get());

        if (parentVtable) {
          ptName = parentVtable->getName();
        }
        subInfo.parents.insert(vtbl_t(ptName, ptIdx));
      }

      bool currRangeCheck = (subInfo.start <= subInfo.addressPoint &&
                     subInfo.addressPoint <= subInfo.end);
      bool prevVtblCheck = (i == op || (--info.subVTables.end())->end < subInfo.start);

      assert(currRangeCheck && prevVtblCheck);

      info.subVTables.push_back(subInfo);
    }
    op += numOperands;

    if (classes.count(info.className) == 0) {
      classes.insert(info.className);
      infoVec.push_back(info);
    }
  } while (op < md->getNumOperands());

  return infoVec;
}