C++ SmallVectorImpl::push_back方法代码示例

bool TailCallElim::EliminateRecursiveTailCall(CallInst *CI, ReturnInst *Ret,
                                       BasicBlock *&OldEntry,
                                       bool &TailCallsAreMarkedTail,
                                       SmallVectorImpl<PHINode *> &ArgumentPHIs,
                                       bool CannotTailCallElimCallsMarkedTail) {
  // If we are introducing accumulator recursion to eliminate operations after
  // the call instruction that are both associative and commutative, the initial
  // value for the accumulator is placed in this variable.  If this value is set
  // then we actually perform accumulator recursion elimination instead of
  // simple tail recursion elimination.  If the operation is an LLVM instruction
  // (eg: "add") then it is recorded in AccumulatorRecursionInstr.  If not, then
  // we are handling the case when the return instruction returns a constant C
  // which is different to the constant returned by other return instructions
  // (which is recorded in AccumulatorRecursionEliminationInitVal).  This is a
  // special case of accumulator recursion, the operation being "return C".
  Value *AccumulatorRecursionEliminationInitVal = 0;
  Instruction *AccumulatorRecursionInstr = 0;

  // Ok, we found a potential tail call.  We can currently only transform the
  // tail call if all of the instructions between the call and the return are
  // movable to above the call itself, leaving the call next to the return.
  // Check that this is the case now.
  BasicBlock::iterator BBI = CI;
  for (++BBI; &*BBI != Ret; ++BBI) {
    if (CanMoveAboveCall(BBI, CI)) continue;

    // If we can't move the instruction above the call, it might be because it
    // is an associative and commutative operation that could be transformed
    // using accumulator recursion elimination.  Check to see if this is the
    // case, and if so, remember the initial accumulator value for later.
    if ((AccumulatorRecursionEliminationInitVal =
                           CanTransformAccumulatorRecursion(BBI, CI))) {
      // Yes, this is accumulator recursion.  Remember which instruction
      // accumulates.
      AccumulatorRecursionInstr = BBI;
    } else {
      return false;   // Otherwise, we cannot eliminate the tail recursion!
    }
  }

  // We can only transform call/return pairs that either ignore the return value
  // of the call and return void, ignore the value of the call and return a
  // constant, return the value returned by the tail call, or that are being
  // accumulator recursion variable eliminated.
  if (Ret->getNumOperands() == 1 && Ret->getReturnValue() != CI &&
      !isa<UndefValue>(Ret->getReturnValue()) &&
      AccumulatorRecursionEliminationInitVal == 0 &&
      !getCommonReturnValue(0, CI)) {
    // One case remains that we are able to handle: the current return
    // instruction returns a constant, and all other return instructions
    // return a different constant.
    if (!isDynamicConstant(Ret->getReturnValue(), CI, Ret))
      return false; // Current return instruction does not return a constant.
    // Check that all other return instructions return a common constant.  If
    // so, record it in AccumulatorRecursionEliminationInitVal.
    AccumulatorRecursionEliminationInitVal = getCommonReturnValue(Ret, CI);
    if (!AccumulatorRecursionEliminationInitVal)
      return false;
  }

  BasicBlock *BB = Ret->getParent();
  Function *F = BB->getParent();

  // OK! We can transform this tail call.  If this is the first one found,
  // create the new entry block, allowing us to branch back to the old entry.
  if (OldEntry == 0) {
    OldEntry = &F->getEntryBlock();
    BasicBlock *NewEntry = BasicBlock::Create(F->getContext(), "", F, OldEntry);
    NewEntry->takeName(OldEntry);
    OldEntry->setName("tailrecurse");
    BranchInst::Create(OldEntry, NewEntry);

    // If this tail call is marked 'tail' and if there are any allocas in the
    // entry block, move them up to the new entry block.
    TailCallsAreMarkedTail = CI->isTailCall();
    if (TailCallsAreMarkedTail)
      // Move all fixed sized allocas from OldEntry to NewEntry.
      for (BasicBlock::iterator OEBI = OldEntry->begin(), E = OldEntry->end(),
             NEBI = NewEntry->begin(); OEBI != E; )
        if (AllocaInst *AI = dyn_cast<AllocaInst>(OEBI++))
          if (isa<ConstantInt>(AI->getArraySize()))
            AI->moveBefore(NEBI);

    // Now that we have created a new block, which jumps to the entry
    // block, insert a PHI node for each argument of the function.
    // For now, we initialize each PHI to only have the real arguments
    // which are passed in.
    Instruction *InsertPos = OldEntry->begin();
    for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end();
         I != E; ++I) {
      PHINode *PN = PHINode::Create(I->getType(), 2,
                                    I->getName() + ".tr", InsertPos);
      I->replaceAllUsesWith(PN); // Everyone use the PHI node now!
      PN->addIncoming(I, NewEntry);
      ArgumentPHIs.push_back(PN);
    }
  }

  // If this function has self recursive calls in the tail position where some
  // are marked tail and some are not, only transform one flavor or another.  We
//.........这里部分代码省略.........

void Mips16TargetLowering::
getOpndList(SmallVectorImpl<SDValue> &Ops,
            std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
            bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
            bool IsCallReloc, CallLoweringInfo &CLI, SDValue Callee,
            SDValue Chain) const {
  SelectionDAG &DAG = CLI.DAG;
  MachineFunction &MF = DAG.getMachineFunction();
  MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
  const char* Mips16HelperFunction = nullptr;
  bool NeedMips16Helper = false;

  if (Subtarget.inMips16HardFloat()) {
    //
    // currently we don't have symbols tagged with the mips16 or mips32
    // qualifier so we will assume that we don't know what kind it is.
    // and generate the helper
    //
    bool LookupHelper = true;
    if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(CLI.Callee)) {
      Mips16Libcall Find = { RTLIB::UNKNOWN_LIBCALL, S->getSymbol() };

      if (std::binary_search(std::begin(HardFloatLibCalls),
                             std::end(HardFloatLibCalls), Find))
        LookupHelper = false;
      else {
        const char *Symbol = S->getSymbol();
        Mips16IntrinsicHelperType IntrinsicFind = { Symbol, "" };
        const Mips16HardFloatInfo::FuncSignature *Signature =
            Mips16HardFloatInfo::findFuncSignature(Symbol);
        if (!IsPICCall && (Signature && (FuncInfo->StubsNeeded.find(Symbol) ==
                                         FuncInfo->StubsNeeded.end()))) {
          FuncInfo->StubsNeeded[Symbol] = Signature;
          //
          // S2 is normally saved if the stub is for a function which
          // returns a float or double value and is not otherwise. This is
          // because more work is required after the function the stub
          // is calling completes, and so the stub cannot directly return
          // and the stub has no stack space to store the return address so
          // S2 is used for that purpose.
          // In order to take advantage of not saving S2, we need to also
          // optimize the call in the stub and this requires some further
          // functionality in MipsAsmPrinter which we don't have yet.
          // So for now we always save S2. The optimization will be done
          // in a follow-on patch.
          //
          if (1 || (Signature->RetSig != Mips16HardFloatInfo::NoFPRet))
            FuncInfo->setSaveS2();
        }
        // one more look at list of intrinsics
        const Mips16IntrinsicHelperType *Helper =
            std::lower_bound(std::begin(Mips16IntrinsicHelper),
                             std::end(Mips16IntrinsicHelper), IntrinsicFind);
        if (Helper != std::end(Mips16IntrinsicHelper) &&
            *Helper == IntrinsicFind) {
          Mips16HelperFunction = Helper->Helper;
          NeedMips16Helper = true;
          LookupHelper = false;
        }

      }
    } else if (GlobalAddressSDNode *G =
                   dyn_cast<GlobalAddressSDNode>(CLI.Callee)) {
      Mips16Libcall Find = { RTLIB::UNKNOWN_LIBCALL,
                             G->getGlobal()->getName().data() };

      if (std::binary_search(std::begin(HardFloatLibCalls),
                             std::end(HardFloatLibCalls), Find))
        LookupHelper = false;
    }
    if (LookupHelper)
      Mips16HelperFunction =
        getMips16HelperFunction(CLI.RetTy, CLI.getArgs(), NeedMips16Helper);
  }

  SDValue JumpTarget = Callee;

  // T9 should contain the address of the callee function if
  // -relocation-model=pic or it is an indirect call.
  if (IsPICCall || !GlobalOrExternal) {
    unsigned V0Reg = Mips::V0;
    if (NeedMips16Helper) {
      RegsToPass.push_front(std::make_pair(V0Reg, Callee));
      JumpTarget = DAG.getExternalSymbol(Mips16HelperFunction,
                                         getPointerTy(DAG.getDataLayout()));
      ExternalSymbolSDNode *S = cast<ExternalSymbolSDNode>(JumpTarget);
      JumpTarget = getAddrGlobal(S, CLI.DL, JumpTarget.getValueType(), DAG,
                                 MipsII::MO_GOT, Chain,
                                 FuncInfo->callPtrInfo(S->getSymbol()));
    } else
      RegsToPass.push_front(std::make_pair((unsigned)Mips::T9, Callee));
  }

  Ops.push_back(JumpTarget);

  MipsTargetLowering::getOpndList(Ops, RegsToPass, IsPICCall, GlobalOrExternal,
                                  InternalLinkage, IsCallReloc, CLI, Callee,
                                  Chain);
}

bool MSP430InstrInfo::analyzeBranch(MachineBasicBlock &MBB,
                                    MachineBasicBlock *&TBB,
                                    MachineBasicBlock *&FBB,
                                    SmallVectorImpl<MachineOperand> &Cond,
                                    bool AllowModify) const {
  // Start from the bottom of the block and work up, examining the
  // terminator instructions.
  MachineBasicBlock::iterator I = MBB.end();
  while (I != MBB.begin()) {
    --I;
    if (I->isDebugValue())
      continue;

    // Working from the bottom, when we see a non-terminator
    // instruction, we're done.
    if (!isUnpredicatedTerminator(*I))
      break;

    // A terminator that isn't a branch can't easily be handled
    // by this analysis.
    if (!I->isBranch())
      return true;

    // Cannot handle indirect branches.
    if (I->getOpcode() == MSP430::Br ||
        I->getOpcode() == MSP430::Bm)
      return true;

    // Handle unconditional branches.
    if (I->getOpcode() == MSP430::JMP) {
      if (!AllowModify) {
        TBB = I->getOperand(0).getMBB();
        continue;
      }

      // If the block has any instructions after a JMP, delete them.
      while (std::next(I) != MBB.end())
        std::next(I)->eraseFromParent();
      Cond.clear();
      FBB = nullptr;

      // Delete the JMP if it's equivalent to a fall-through.
      if (MBB.isLayoutSuccessor(I->getOperand(0).getMBB())) {
        TBB = nullptr;
        I->eraseFromParent();
        I = MBB.end();
        continue;
      }

      // TBB is used to indicate the unconditinal destination.
      TBB = I->getOperand(0).getMBB();
      continue;
    }

    // Handle conditional branches.
    assert(I->getOpcode() == MSP430::JCC && "Invalid conditional branch");
    MSP430CC::CondCodes BranchCode =
      static_cast<MSP430CC::CondCodes>(I->getOperand(1).getImm());
    if (BranchCode == MSP430CC::COND_INVALID)
      return true;  // Can't handle weird stuff.

    // Working from the bottom, handle the first conditional branch.
    if (Cond.empty()) {
      FBB = TBB;
      TBB = I->getOperand(0).getMBB();
      Cond.push_back(MachineOperand::CreateImm(BranchCode));
      continue;
    }

    // Handle subsequent conditional branches. Only handle the case where all
    // conditional branches branch to the same destination.
    assert(Cond.size() == 1);
    assert(TBB);

    // Only handle the case where all conditional branches branch to
    // the same destination.
    if (TBB != I->getOperand(0).getMBB())
      return true;

    MSP430CC::CondCodes OldBranchCode = (MSP430CC::CondCodes)Cond[0].getImm();
    // If the conditions are the same, we can leave them alone.
    if (OldBranchCode == BranchCode)
      continue;

    return true;
  }

  return false;
}

void RValue::getAllUnmanaged(SmallVectorImpl<SILValue> &dest) const & {
  assert(isComplete() && "rvalue is not complete");

  for (auto value : values)
    dest.push_back(value.getUnmanagedValue());
}

bool SparcInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
                                   MachineBasicBlock *&TBB,
                                   MachineBasicBlock *&FBB,
                                   SmallVectorImpl<MachineOperand> &Cond,
                                   bool AllowModify) const
{

  MachineBasicBlock::iterator I = MBB.end();
  MachineBasicBlock::iterator UnCondBrIter = MBB.end();
  while (I != MBB.begin()) {
    --I;

    if (I->isDebugValue())
      continue;

    // When we see a non-terminator, we are done.
    if (!isUnpredicatedTerminator(I))
      break;

    // Terminator is not a branch.
    if (!I->isBranch())
      return true;

    // Handle Unconditional branches.
    if (I->getOpcode() == SP::BA) {
      UnCondBrIter = I;

      if (!AllowModify) {
        TBB = I->getOperand(0).getMBB();
        continue;
      }

      while (llvm::next(I) != MBB.end())
        llvm::next(I)->eraseFromParent();

      Cond.clear();
      FBB = 0;

      if (MBB.isLayoutSuccessor(I->getOperand(0).getMBB())) {
        TBB = 0;
        I->eraseFromParent();
        I = MBB.end();
        UnCondBrIter = MBB.end();
        continue;
      }

      TBB = I->getOperand(0).getMBB();
      continue;
    }

    unsigned Opcode = I->getOpcode();
    if (Opcode != SP::BCOND && Opcode != SP::FBCOND)
      return true; // Unknown Opcode.

    SPCC::CondCodes BranchCode = (SPCC::CondCodes)I->getOperand(1).getImm();

    if (Cond.empty()) {
      MachineBasicBlock *TargetBB = I->getOperand(0).getMBB();
      if (AllowModify && UnCondBrIter != MBB.end() &&
          MBB.isLayoutSuccessor(TargetBB)) {

        // Transform the code
        //
        //    brCC L1
        //    ba L2
        // L1:
        //    ..
        // L2:
        //
        // into
        //
        //   brnCC L2
        // L1:
        //   ...
        // L2:
        //
        BranchCode = GetOppositeBranchCondition(BranchCode);
        MachineBasicBlock::iterator OldInst = I;
        BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(Opcode))
          .addMBB(UnCondBrIter->getOperand(0).getMBB()).addImm(BranchCode);
        BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(SP::BA))
          .addMBB(TargetBB);

        OldInst->eraseFromParent();
        UnCondBrIter->eraseFromParent();

        UnCondBrIter = MBB.end();
        I = MBB.end();
        continue;
      }
      FBB = TBB;
      TBB = I->getOperand(0).getMBB();
      Cond.push_back(MachineOperand::CreateImm(BranchCode));
      continue;
    }
    // FIXME: Handle subsequent conditional branches.
    // For now, we can't handle multiple conditional branches.
    return true;
  }
  return false;
//.........这里部分代码省略.........

/// ApplyQAOverride - Apply a list of edits to the input argument lists.
///
/// The input string is a space separate list of edits to perform,
/// they are applied in order to the input argument lists. Edits
/// should be one of the following forms:
///
///  '#': Silence information about the changes to the command line arguments.
///
///  '^': Add FOO as a new argument at the beginning of the command line.
///
///  '+': Add FOO as a new argument at the end of the command line.
///
///  's/XXX/YYY/': Substitute the regular expression XXX with YYY in the command
///  line.
///
///  'xOPTION': Removes all instances of the literal argument OPTION.
///
///  'XOPTION': Removes all instances of the literal argument OPTION,
///  and the following argument.
///
///  'Ox': Removes all flags matching 'O' or 'O[sz0-9]' and adds 'Ox'
///  at the end of the command line.
///
/// \param OS - The stream to write edit information to.
/// \param Args - The vector of command line arguments.
/// \param Edit - The override command to perform.
/// \param SavedStrings - Set to use for storing string representations.
static void ApplyOneQAOverride(raw_ostream &OS,
                               SmallVectorImpl<const char*> &Args,
                               StringRef Edit,
                               std::set<std::string> &SavedStrings) {
  // This does not need to be efficient.

  if (Edit[0] == '^') {
    const char *Str =
      SaveStringInSet(SavedStrings, Edit.substr(1));
    OS << "### Adding argument " << Str << " at beginning\n";
    Args.insert(Args.begin() + 1, Str);
  } else if (Edit[0] == '+') {
    const char *Str =
      SaveStringInSet(SavedStrings, Edit.substr(1));
    OS << "### Adding argument " << Str << " at end\n";
    Args.push_back(Str);
  } else if (Edit[0] == 's' && Edit[1] == '/' && Edit.endswith("/") &&
             Edit.slice(2, Edit.size()-1).find('/') != StringRef::npos) {
    StringRef MatchPattern = Edit.substr(2).split('/').first;
    StringRef ReplPattern = Edit.substr(2).split('/').second;
    ReplPattern = ReplPattern.slice(0, ReplPattern.size()-1);

    for (unsigned i = 1, e = Args.size(); i != e; ++i) {
      std::string Repl = llvm::Regex(MatchPattern).sub(ReplPattern, Args[i]);

      if (Repl != Args[i]) {
        OS << "### Replacing '" << Args[i] << "' with '" << Repl << "'\n";
        Args[i] = SaveStringInSet(SavedStrings, Repl);
      }
    }
  } else if (Edit[0] == 'x' || Edit[0] == 'X') {
    std::string Option = Edit.substr(1, std::string::npos);
    for (unsigned i = 1; i < Args.size();) {
      if (Option == Args[i]) {
        OS << "### Deleting argument " << Args[i] << '\n';
        Args.erase(Args.begin() + i);
        if (Edit[0] == 'X') {
          if (i < Args.size()) {
            OS << "### Deleting argument " << Args[i] << '\n';
            Args.erase(Args.begin() + i);
          } else
            OS << "### Invalid X edit, end of command line!\n";
        }
      } else
        ++i;
    }
  } else if (Edit[0] == 'O') {
    for (unsigned i = 1; i < Args.size();) {
      const char *A = Args[i];
      if (A[0] == '-' && A[1] == 'O' &&
          (A[2] == '\0' ||
           (A[3] == '\0' && (A[2] == 's' || A[2] == 'z' ||
                             ('0' <= A[2] && A[2] <= '9'))))) {
        OS << "### Deleting argument " << Args[i] << '\n';
        Args.erase(Args.begin() + i);
      } else
        ++i;
    }
    OS << "### Adding argument " << Edit << " at end\n";
    Args.push_back(SaveStringInSet(SavedStrings, '-' + Edit.str()));
  } else {
    OS << "### Unrecognized edit: " << Edit << "\n";
  }
}

bool extractParameterOutline(
    llvm::markup::MarkupContext &MC, llvm::markup::List *L,
    SmallVectorImpl<const llvm::markup::ParamField *> &ParamFields) {
  SmallVector<llvm::markup::MarkupASTNode *, 8> NormalItems;
  auto Children = L->getChildren();
  if (Children.empty())
    return false;

  for (auto Child : Children) {
    auto I = dyn_cast<llvm::markup::Item>(Child);
    if (!I) {
      NormalItems.push_back(Child);
      continue;
    }

    auto ItemChildren = I->getChildren();
    if (ItemChildren.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    auto FirstChild = ItemChildren.front();
    auto FirstParagraph = dyn_cast<llvm::markup::Paragraph>(FirstChild);
    if (!FirstParagraph) {
      NormalItems.push_back(Child);
      continue;
    }

    auto FirstParagraphChildren = FirstParagraph->getChildren();
    if (FirstParagraphChildren.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    auto HeadingText
        = dyn_cast<llvm::markup::Text>(FirstParagraphChildren.front());
    if (!HeadingText) {
      NormalItems.push_back(Child);
      continue;
    }

    auto HeadingContent = HeadingText->getLiteralContent();
    if (!HeadingContent.rtrim().equals_lower("parameters:")) {
      NormalItems.push_back(Child);
      continue;
    }

    auto Rest = ArrayRef<llvm::markup::MarkupASTNode *>(
        ItemChildren.begin() + 1, ItemChildren.end());
    if (Rest.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    for (auto Child : Rest) {
      auto SubList = dyn_cast<llvm::markup::List>(Child);
      if (!SubList)
        continue;

      for (auto SubListChild : SubList->getChildren()) {
        auto Param = extractParamOutlineItem(MC, SubListChild);
        if (Param.hasValue()) {
          ParamFields.push_back(Param.getValue());
        }
      }
    }
  }

  if (NormalItems.size() != Children.size()) {
    L->setChildren(NormalItems);
  }

  return NormalItems.size() == 0;
}

void MatcherGen::
EmitResultInstructionAsOperand(const TreePatternNode *N,
                               SmallVectorImpl<unsigned> &OutputOps) {
  Record *Op = N->getOperator();
  const CodeGenTarget &CGT = CGP.getTargetInfo();
  CodeGenInstruction &II = CGT.getInstruction(Op);
  const DAGInstruction &Inst = CGP.getInstruction(Op);

  // If we can, get the pattern for the instruction we're generating.  We derive
  // a variety of information from this pattern, such as whether it has a chain.
  //
  // FIXME2: This is extremely dubious for several reasons, not the least of
  // which it gives special status to instructions with patterns that Pat<>
  // nodes can't duplicate.
  const TreePatternNode *InstPatNode = GetInstPatternNode(Inst, N);

  // NodeHasChain - Whether the instruction node we're creating takes chains.
  bool NodeHasChain = InstPatNode &&
                      InstPatNode->TreeHasProperty(SDNPHasChain, CGP);

  bool isRoot = N == Pattern.getDstPattern();

  // TreeHasOutGlue - True if this tree has glue.
  bool TreeHasInGlue = false, TreeHasOutGlue = false;
  if (isRoot) {
    const TreePatternNode *SrcPat = Pattern.getSrcPattern();
    TreeHasInGlue = SrcPat->TreeHasProperty(SDNPOptInGlue, CGP) ||
                    SrcPat->TreeHasProperty(SDNPInGlue, CGP);

    // FIXME2: this is checking the entire pattern, not just the node in
    // question, doing this just for the root seems like a total hack.
    TreeHasOutGlue = SrcPat->TreeHasProperty(SDNPOutGlue, CGP);
  }

  // NumResults - This is the number of results produced by the instruction in
  // the "outs" list.
  unsigned NumResults = Inst.getNumResults();

  // Loop over all of the operands of the instruction pattern, emitting code
  // to fill them all in.  The node 'N' usually has number children equal to
  // the number of input operands of the instruction.  However, in cases
  // where there are predicate operands for an instruction, we need to fill
  // in the 'execute always' values.  Match up the node operands to the
  // instruction operands to do this.
  SmallVector<unsigned, 8> InstOps;
  for (unsigned ChildNo = 0, InstOpNo = NumResults, e = II.Operands.size();
       InstOpNo != e; ++InstOpNo) {

    // Determine what to emit for this operand.
    Record *OperandNode = II.Operands[InstOpNo].Rec;
    if ((OperandNode->isSubClassOf("PredicateOperand") ||
         OperandNode->isSubClassOf("OptionalDefOperand")) &&
        !CGP.getDefaultOperand(OperandNode).DefaultOps.empty()) {
      // This is a predicate or optional def operand; emit the
      // 'default ops' operands.
      const DAGDefaultOperand &DefaultOp
        = CGP.getDefaultOperand(OperandNode);
      for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i)
        EmitResultOperand(DefaultOp.DefaultOps[i], InstOps);
      continue;
    }

    const TreePatternNode *Child = N->getChild(ChildNo);

    // Otherwise this is a normal operand or a predicate operand without
    // 'execute always'; emit it.
    unsigned BeforeAddingNumOps = InstOps.size();
    EmitResultOperand(Child, InstOps);
    assert(InstOps.size() > BeforeAddingNumOps && "Didn't add any operands");

    // If the operand is an instruction and it produced multiple results, just
    // take the first one.
    if (!Child->isLeaf() && Child->getOperator()->isSubClassOf("Instruction"))
      InstOps.resize(BeforeAddingNumOps+1);

    ++ChildNo;
  }

  // If this node has input glue or explicitly specified input physregs, we
  // need to add chained and glued copyfromreg nodes and materialize the glue
  // input.
  if (isRoot && !PhysRegInputs.empty()) {
    // Emit all of the CopyToReg nodes for the input physical registers.  These
    // occur in patterns like (mul:i8 AL:i8, GR8:i8:$src).
    for (unsigned i = 0, e = PhysRegInputs.size(); i != e; ++i)
      AddMatcher(new EmitCopyToRegMatcher(PhysRegInputs[i].second,
                                          PhysRegInputs[i].first));
    // Even if the node has no other glue inputs, the resultant node must be
    // glued to the CopyFromReg nodes we just generated.
    TreeHasInGlue = true;
  }

  // Result order: node results, chain, glue

  // Determine the result types.
  SmallVector<MVT::SimpleValueType, 4> ResultVTs;
  for (unsigned i = 0, e = N->getNumTypes(); i != e; ++i)
    ResultVTs.push_back(N->getType(i));

  // If this is the root instruction of a pattern that has physical registers in
//.........这里部分代码省略.........

bool extractSeparatedParams(
    llvm::markup::MarkupContext &MC, llvm::markup::List *L,
    SmallVectorImpl<const llvm::markup::ParamField *> &ParamFields) {
  SmallVector<llvm::markup::MarkupASTNode *, 8> NormalItems;
  auto Children = L->getChildren();

  for (auto Child : Children) {
    auto I = dyn_cast<llvm::markup::Item>(Child);
    if (!I) {
      NormalItems.push_back(Child);
      continue;
    }

    auto ItemChildren = I->getChildren();
    if (ItemChildren.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    auto FirstChild = ItemChildren.front();
    auto FirstParagraph = dyn_cast<llvm::markup::Paragraph>(FirstChild);
    if (!FirstParagraph) {
      NormalItems.push_back(Child);
      continue;
    }

    auto FirstParagraphChildren = FirstParagraph->getChildren();
    if (FirstParagraphChildren.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    auto ParagraphText
        = dyn_cast<llvm::markup::Text>(FirstParagraphChildren.front());
    if (!ParagraphText) {
      NormalItems.push_back(Child);
      continue;
    }

    StringRef ParameterPrefix("parameter ");
    auto ParagraphContent = ParagraphText->getLiteralContent();
    auto PotentialMatch = ParagraphContent.substr(0, ParameterPrefix.size());

    if (!PotentialMatch.startswith_lower(ParameterPrefix)) {
      NormalItems.push_back(Child);
      continue;
    }

    ParagraphContent = ParagraphContent.substr(ParameterPrefix.size());
    ParagraphText->setLiteralContent(ParagraphContent.ltrim());

    auto ParamField = extractParamOutlineItem(MC, I);
    if (ParamField.hasValue())
      ParamFields.push_back(ParamField.getValue());
    else
      NormalItems.push_back(Child);
  }

  if (NormalItems.size() != Children.size())
    L->setChildren(NormalItems);

  return NormalItems.size() == 0;
}

bool extractSimpleField(
    llvm::markup::MarkupContext &MC, llvm::markup::List *L,
    DocComment::CommentParts &Parts,
    SmallVectorImpl<const llvm::markup::MarkupASTNode *> &BodyNodes) {
  auto Children = L->getChildren();
  SmallVector<llvm::markup::MarkupASTNode *, 8> NormalItems;
  for (auto Child : Children) {
    auto I = dyn_cast<llvm::markup::Item>(Child);
    if (!I) {
      NormalItems.push_back(Child);
      continue;
    }

    auto ItemChildren = I->getChildren();
    if (ItemChildren.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    auto FirstParagraph
        = dyn_cast<llvm::markup::Paragraph>(ItemChildren.front());
    if (!FirstParagraph) {
      NormalItems.push_back(Child);
      continue;
    }

    auto ParagraphChildren = FirstParagraph->getChildren();
    if (ParagraphChildren.empty()) {
      NormalItems.push_back(Child);
      continue;
    }

    auto ParagraphText
        = dyn_cast<llvm::markup::Text>(ParagraphChildren.front());
    if (!ParagraphText) {
      NormalItems.push_back(Child);
      continue;
    }

    StringRef Tag;
    StringRef Remainder;
    std::tie(Tag, Remainder) = ParagraphText->getLiteralContent().split(':');
    Tag = Tag.ltrim().rtrim();
    Remainder = Remainder.ltrim();

    if (!llvm::markup::isAFieldTag(Tag)) {
      NormalItems.push_back(Child);
      continue;
    }

    ParagraphText->setLiteralContent(Remainder);
    auto Field = llvm::markup::createSimpleField(MC, Tag, ItemChildren);

    if (auto RF = dyn_cast<llvm::markup::ReturnsField>(Field))
      Parts.ReturnsField = RF;
    else if (auto TF = dyn_cast<llvm::markup::ThrowsField>(Field))
      Parts.ThrowsField = TF;
    else
      BodyNodes.push_back(Field);
  }

  if (NormalItems.size() != Children.size())
    L->setChildren(NormalItems);

  return NormalItems.size() == 0;
}

void SILGenFunction::emitCaptures(SILLocation loc,
                                  AnyFunctionRef TheClosure,
                                  SmallVectorImpl<ManagedValue> &capturedArgs) {
  auto captureInfo = SGM.Types.getLoweredLocalCaptures(TheClosure);
  // For boxed captures, we need to mark the contained variables as having
  // escaped for DI diagnostics.
  SmallVector<SILValue, 2> escapesToMark;
  
  for (auto capture : captureInfo.getCaptures()) {
    auto *vd = capture.getDecl();

    switch (SGM.Types.getDeclCaptureKind(capture)) {
    case CaptureKind::None:
      break;

    case CaptureKind::Constant: {
      // let declarations.
      auto Entry = VarLocs[vd];

      // Non-address-only constants are passed at +1.
      auto &tl = getTypeLowering(vd->getType()->getReferenceStorageReferent());
      SILValue Val = Entry.value;

      if (!Val.getType().isAddress()) {
        // Just retain a by-val let.
        B.emitRetainValueOperation(loc, Val);
      } else {
        // If we have a mutable binding for a 'let', such as 'self' in an
        // 'init' method, load it.
        Val = emitLoad(loc, Val, tl, SGFContext(), IsNotTake).forward(*this);
      }

      // Use an RValue to explode Val if it is a tuple.
      RValue RV(*this, loc, vd->getType()->getCanonicalType(),
                ManagedValue::forUnmanaged(Val));

      // If we're capturing an unowned pointer by value, we will have just
      // loaded it into a normal retained class pointer, but we capture it as
      // an unowned pointer.  Convert back now.
      if (vd->getType()->is<ReferenceStorageType>()) {
        auto type = getTypeLowering(vd->getType()).getLoweredType();
        auto val = std::move(RV).forwardAsSingleStorageValue(*this, type,loc);
        capturedArgs.push_back(emitManagedRValueWithCleanup(val));
      } else {
        std::move(RV).getAll(capturedArgs);
      }
      break;
    }

    case CaptureKind::StorageAddress: {
      // No-escaping stored declarations are captured as the
      // address of the value.
      assert(VarLocs.count(vd) && "no location for captured var!");
      VarLoc vl = VarLocs[vd];
      assert(vl.value.getType().isAddress() && "no address for captured var!");
      capturedArgs.push_back(ManagedValue::forLValue(vl.value));
      break;
    }

    case CaptureKind::Box: {
      // LValues are captured as both the box owning the value and the
      // address of the value.
      assert(VarLocs.count(vd) && "no location for captured var!");
      VarLoc vl = VarLocs[vd];
      assert(vl.value.getType().isAddress() && "no address for captured var!");

      // If this is a boxed variable, we can use it directly.
      if (vl.box) {
        B.createStrongRetain(loc, vl.box);
        capturedArgs.push_back(emitManagedRValueWithCleanup(vl.box));
        escapesToMark.push_back(vl.value);
      } else {
        // Address only 'let' values are passed by box.  This isn't great, in
        // that a variable captured by multiple closures will be boxed for each
        // one.  This could be improved by doing an "isCaptured" analysis when
        // emitting address-only let constants, and emit them into a alloc_box
        // like a variable instead of into an alloc_stack.
        AllocBoxInst *allocBox =
          B.createAllocBox(loc, vl.value.getType().getObjectType());
        auto boxAddress = SILValue(allocBox, 1);
        B.createCopyAddr(loc, vl.value, boxAddress, IsNotTake,IsInitialization);
        capturedArgs.push_back(emitManagedRValueWithCleanup(SILValue(allocBox, 0)));
      }

      break;
    }
    }
  }
  
  // Mark box addresses as captured for DI purposes. The values must have
  // been fully initialized before we close over them.
  if (!escapesToMark.empty()) {
    B.createMarkFunctionEscape(loc, escapesToMark);
  }
}

void DiagnosticIDs::getAllDiagnostics(
                               SmallVectorImpl<diag::kind> &Diags) const {
  for (unsigned i = 0; i != StaticDiagInfoSize; ++i)
    Diags.push_back(StaticDiagInfo[i].DiagID);
}

static void parseCondBranch(MachineInstr *LastInst, MachineBasicBlock *&Target,
                            SmallVectorImpl<MachineOperand> &Cond) {
  Cond.push_back(MachineOperand::CreateImm(LastInst->getOperand(1).getImm()));
  Target = LastInst->getOperand(0).getMBB();
}

void Diagnostic::
FormatDiagnostic(const char *DiagStr, const char *DiagEnd,
                 SmallVectorImpl<char> &OutStr) const {

  /// FormattedArgs - Keep track of all of the arguments formatted by
  /// ConvertArgToString and pass them into subsequent calls to
  /// ConvertArgToString, allowing the implementation to avoid redundancies in
  /// obvious cases.
  SmallVector<DiagnosticsEngine::ArgumentValue, 8> FormattedArgs;

  /// QualTypeVals - Pass a vector of arrays so that QualType names can be
  /// compared to see if more information is needed to be printed.
  SmallVector<intptr_t, 2> QualTypeVals;
  SmallVector<char, 64> Tree;

  for (unsigned i = 0, e = getNumArgs(); i < e; ++i)
    if (getArgKind(i) == DiagnosticsEngine::ak_qualtype)
      QualTypeVals.push_back(getRawArg(i));

  while (DiagStr != DiagEnd) {
    if (DiagStr[0] != '%') {
      // Append non-%0 substrings to Str if we have one.
      const char *StrEnd = std::find(DiagStr, DiagEnd, '%');
      OutStr.append(DiagStr, StrEnd);
      DiagStr = StrEnd;
      continue;
    } else if (ispunct(DiagStr[1])) {
      OutStr.push_back(DiagStr[1]);  // %% -> %.
      DiagStr += 2;
      continue;
    }

    // Skip the %.
    ++DiagStr;

    // This must be a placeholder for a diagnostic argument.  The format for a
    // placeholder is one of "%0", "%modifier0", or "%modifier{arguments}0".
    // The digit is a number from 0-9 indicating which argument this comes from.
    // The modifier is a string of digits from the set [-a-z]+, arguments is a
    // brace enclosed string.
    const char *Modifier = 0, *Argument = 0;
    unsigned ModifierLen = 0, ArgumentLen = 0;

    // Check to see if we have a modifier.  If so eat it.
    if (!isdigit(DiagStr[0])) {
      Modifier = DiagStr;
      while (DiagStr[0] == '-' ||
             (DiagStr[0] >= 'a' && DiagStr[0] <= 'z'))
        ++DiagStr;
      ModifierLen = DiagStr-Modifier;

      // If we have an argument, get it next.
      if (DiagStr[0] == '{') {
        ++DiagStr; // Skip {.
        Argument = DiagStr;

        DiagStr = ScanFormat(DiagStr, DiagEnd, '}');
        assert(DiagStr != DiagEnd && "Mismatched {}'s in diagnostic string!");
        ArgumentLen = DiagStr-Argument;
        ++DiagStr;  // Skip }.
      }
    }

    assert(isdigit(*DiagStr) && "Invalid format for argument in diagnostic");
    unsigned ArgNo = *DiagStr++ - '0';

    // Only used for type diffing.
    unsigned ArgNo2 = ArgNo;

    DiagnosticsEngine::ArgumentKind Kind = getArgKind(ArgNo);
    if (Kind == DiagnosticsEngine::ak_qualtype &&
        ModifierIs(Modifier, ModifierLen, "diff")) {
      Kind = DiagnosticsEngine::ak_qualtype_pair;
      assert(*DiagStr == ',' && isdigit(*(DiagStr + 1)) &&
             "Invalid format for diff modifier");
      ++DiagStr;  // Comma.
      ArgNo2 = *DiagStr++ - '0';
      assert(getArgKind(ArgNo2) == DiagnosticsEngine::ak_qualtype &&
             "Second value of type diff must be a qualtype");
    }
    
    switch (Kind) {
    // ---- STRINGS ----
    case DiagnosticsEngine::ak_std_string: {
      const std::string &S = getArgStdStr(ArgNo);
      assert(ModifierLen == 0 && "No modifiers for strings yet");
      OutStr.append(S.begin(), S.end());
      break;
    }
    case DiagnosticsEngine::ak_c_string: {
      const char *S = getArgCStr(ArgNo);
      assert(ModifierLen == 0 && "No modifiers for strings yet");

      // Don't crash if get passed a null pointer by accident.
      if (!S)
        S = "(null)";

      OutStr.append(S, S + strlen(S));
      break;
    }
//.........这里部分代码省略.........

SDValue BPFTargetLowering::LowerFormalArguments(
    SDValue Chain, CallingConv::ID CallConv, bool IsVarArg,
    const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &DL,
    SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
  switch (CallConv) {
  default:
    llvm_unreachable("Unsupported calling convention");
  case CallingConv::C:
  case CallingConv::Fast:
    break;
  }

  MachineFunction &MF = DAG.getMachineFunction();
  MachineRegisterInfo &RegInfo = MF.getRegInfo();

  // Assign locations to all of the incoming arguments.
  SmallVector<CCValAssign, 16> ArgLocs;
  CCState CCInfo(CallConv, IsVarArg, MF, ArgLocs, *DAG.getContext());
  CCInfo.AnalyzeFormalArguments(Ins, CC_BPF64);

  for (auto &VA : ArgLocs) {
    if (VA.isRegLoc()) {
      // Arguments passed in registers
      EVT RegVT = VA.getLocVT();
      switch (RegVT.getSimpleVT().SimpleTy) {
      default: {
        errs() << "LowerFormalArguments Unhandled argument type: "
               << RegVT.getEVTString() << '\n';
        llvm_unreachable(0);
      }
      case MVT::i64:
        unsigned VReg = RegInfo.createVirtualRegister(&BPF::GPRRegClass);
        RegInfo.addLiveIn(VA.getLocReg(), VReg);
        SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, VReg, RegVT);

        // If this is an 8/16/32-bit value, it is really passed promoted to 64
        // bits. Insert an assert[sz]ext to capture this, then truncate to the
        // right size.
        if (VA.getLocInfo() == CCValAssign::SExt)
          ArgValue = DAG.getNode(ISD::AssertSext, DL, RegVT, ArgValue,
                                 DAG.getValueType(VA.getValVT()));
        else if (VA.getLocInfo() == CCValAssign::ZExt)
          ArgValue = DAG.getNode(ISD::AssertZext, DL, RegVT, ArgValue,
                                 DAG.getValueType(VA.getValVT()));

        if (VA.getLocInfo() != CCValAssign::Full)
          ArgValue = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), ArgValue);

        InVals.push_back(ArgValue);
      }
    } else {
      fail(DL, DAG, "defined with too many args");
      InVals.push_back(DAG.getConstant(0, DL, VA.getLocVT()));
    }
  }

  if (IsVarArg || MF.getFunction()->hasStructRetAttr()) {
    fail(DL, DAG, "functions with VarArgs or StructRet are not supported");
  }

  return Chain;
}