It's not necessary to do rounding for alloca operations when the requested
alignment is equal to the stack alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/DAGISelEmitter.cpp b/utils/TableGen/DAGISelEmitter.cpp
new file mode 100644
index 0000000..fcad318
--- /dev/null
+++ b/utils/TableGen/DAGISelEmitter.cpp
@@ -0,0 +1,4001 @@
+//===- DAGISelEmitter.cpp - Generate an instruction selector --------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This tablegen backend emits a DAG instruction selector.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DAGISelEmitter.h"
+#include "Record.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/Streams.h"
+#include <algorithm>
+#include <set>
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// Helpers for working with extended types.
+
+/// FilterVTs - Filter a list of VT's according to a predicate.
+///
+template<typename T>
+static std::vector<MVT::ValueType> 
+FilterVTs(const std::vector<MVT::ValueType> &InVTs, T Filter) {
+  std::vector<MVT::ValueType> Result;
+  for (unsigned i = 0, e = InVTs.size(); i != e; ++i)
+    if (Filter(InVTs[i]))
+      Result.push_back(InVTs[i]);
+  return Result;
+}
+
+template<typename T>
+static std::vector<unsigned char> 
+FilterEVTs(const std::vector<unsigned char> &InVTs, T Filter) {
+  std::vector<unsigned char> Result;
+  for (unsigned i = 0, e = InVTs.size(); i != e; ++i)
+    if (Filter((MVT::ValueType)InVTs[i]))
+      Result.push_back(InVTs[i]);
+  return Result;
+}
+
+static std::vector<unsigned char>
+ConvertVTs(const std::vector<MVT::ValueType> &InVTs) {
+  std::vector<unsigned char> Result;
+  for (unsigned i = 0, e = InVTs.size(); i != e; ++i)
+      Result.push_back(InVTs[i]);
+  return Result;
+}
+
+static bool LHSIsSubsetOfRHS(const std::vector<unsigned char> &LHS,
+                             const std::vector<unsigned char> &RHS) {
+  if (LHS.size() > RHS.size()) return false;
+  for (unsigned i = 0, e = LHS.size(); i != e; ++i)
+    if (std::find(RHS.begin(), RHS.end(), LHS[i]) == RHS.end())
+      return false;
+  return true;
+}
+
+/// isExtIntegerVT - Return true if the specified extended value type vector
+/// contains isInt or an integer value type.
+static bool isExtIntegerInVTs(const std::vector<unsigned char> &EVTs) {
+  assert(!EVTs.empty() && "Cannot check for integer in empty ExtVT list!");
+  return EVTs[0] == MVT::isInt || !(FilterEVTs(EVTs, MVT::isInteger).empty());
+}
+
+/// isExtFloatingPointVT - Return true if the specified extended value type 
+/// vector contains isFP or a FP value type.
+static bool isExtFloatingPointInVTs(const std::vector<unsigned char> &EVTs) {
+  assert(!EVTs.empty() && "Cannot check for integer in empty ExtVT list!");
+  return EVTs[0] == MVT::isFP ||
+         !(FilterEVTs(EVTs, MVT::isFloatingPoint).empty());
+}
+
+//===----------------------------------------------------------------------===//
+// SDTypeConstraint implementation
+//
+
+SDTypeConstraint::SDTypeConstraint(Record *R) {
+  OperandNo = R->getValueAsInt("OperandNum");
+  
+  if (R->isSubClassOf("SDTCisVT")) {
+    ConstraintType = SDTCisVT;
+    x.SDTCisVT_Info.VT = getValueType(R->getValueAsDef("VT"));
+  } else if (R->isSubClassOf("SDTCisPtrTy")) {
+    ConstraintType = SDTCisPtrTy;
+  } else if (R->isSubClassOf("SDTCisInt")) {
+    ConstraintType = SDTCisInt;
+  } else if (R->isSubClassOf("SDTCisFP")) {
+    ConstraintType = SDTCisFP;
+  } else if (R->isSubClassOf("SDTCisSameAs")) {
+    ConstraintType = SDTCisSameAs;
+    x.SDTCisSameAs_Info.OtherOperandNum = R->getValueAsInt("OtherOperandNum");
+  } else if (R->isSubClassOf("SDTCisVTSmallerThanOp")) {
+    ConstraintType = SDTCisVTSmallerThanOp;
+    x.SDTCisVTSmallerThanOp_Info.OtherOperandNum = 
+      R->getValueAsInt("OtherOperandNum");
+  } else if (R->isSubClassOf("SDTCisOpSmallerThanOp")) {
+    ConstraintType = SDTCisOpSmallerThanOp;
+    x.SDTCisOpSmallerThanOp_Info.BigOperandNum = 
+      R->getValueAsInt("BigOperandNum");
+  } else if (R->isSubClassOf("SDTCisIntVectorOfSameSize")) {
+    ConstraintType = SDTCisIntVectorOfSameSize;
+    x.SDTCisIntVectorOfSameSize_Info.OtherOperandNum =
+      R->getValueAsInt("OtherOpNum");
+  } else {
+    cerr << "Unrecognized SDTypeConstraint '" << R->getName() << "'!\n";
+    exit(1);
+  }
+}
+
+/// getOperandNum - Return the node corresponding to operand #OpNo in tree
+/// N, which has NumResults results.
+TreePatternNode *SDTypeConstraint::getOperandNum(unsigned OpNo,
+                                                 TreePatternNode *N,
+                                                 unsigned NumResults) const {
+  assert(NumResults <= 1 &&
+         "We only work with nodes with zero or one result so far!");
+  
+  if (OpNo >= (NumResults + N->getNumChildren())) {
+    cerr << "Invalid operand number " << OpNo << " ";
+    N->dump();
+    cerr << '\n';
+    exit(1);
+  }
+
+  if (OpNo < NumResults)
+    return N;  // FIXME: need value #
+  else
+    return N->getChild(OpNo-NumResults);
+}
+
+/// ApplyTypeConstraint - Given a node in a pattern, apply this type
+/// constraint to the nodes operands.  This returns true if it makes a
+/// change, false otherwise.  If a type contradiction is found, throw an
+/// exception.
+bool SDTypeConstraint::ApplyTypeConstraint(TreePatternNode *N,
+                                           const SDNodeInfo &NodeInfo,
+                                           TreePattern &TP) const {
+  unsigned NumResults = NodeInfo.getNumResults();
+  assert(NumResults <= 1 &&
+         "We only work with nodes with zero or one result so far!");
+  
+  // Check that the number of operands is sane.  Negative operands -> varargs.
+  if (NodeInfo.getNumOperands() >= 0) {
+    if (N->getNumChildren() != (unsigned)NodeInfo.getNumOperands())
+      TP.error(N->getOperator()->getName() + " node requires exactly " +
+               itostr(NodeInfo.getNumOperands()) + " operands!");
+  }
+
+  const CodeGenTarget &CGT = TP.getDAGISelEmitter().getTargetInfo();
+  
+  TreePatternNode *NodeToApply = getOperandNum(OperandNo, N, NumResults);
+  
+  switch (ConstraintType) {
+  default: assert(0 && "Unknown constraint type!");
+  case SDTCisVT:
+    // Operand must be a particular type.
+    return NodeToApply->UpdateNodeType(x.SDTCisVT_Info.VT, TP);
+  case SDTCisPtrTy: {
+    // Operand must be same as target pointer type.
+    return NodeToApply->UpdateNodeType(MVT::iPTR, TP);
+  }
+  case SDTCisInt: {
+    // If there is only one integer type supported, this must be it.
+    std::vector<MVT::ValueType> IntVTs =
+      FilterVTs(CGT.getLegalValueTypes(), MVT::isInteger);
+
+    // If we found exactly one supported integer type, apply it.
+    if (IntVTs.size() == 1)
+      return NodeToApply->UpdateNodeType(IntVTs[0], TP);
+    return NodeToApply->UpdateNodeType(MVT::isInt, TP);
+  }
+  case SDTCisFP: {
+    // If there is only one FP type supported, this must be it.
+    std::vector<MVT::ValueType> FPVTs =
+      FilterVTs(CGT.getLegalValueTypes(), MVT::isFloatingPoint);
+        
+    // If we found exactly one supported FP type, apply it.
+    if (FPVTs.size() == 1)
+      return NodeToApply->UpdateNodeType(FPVTs[0], TP);
+    return NodeToApply->UpdateNodeType(MVT::isFP, TP);
+  }
+  case SDTCisSameAs: {
+    TreePatternNode *OtherNode =
+      getOperandNum(x.SDTCisSameAs_Info.OtherOperandNum, N, NumResults);
+    return NodeToApply->UpdateNodeType(OtherNode->getExtTypes(), TP) |
+           OtherNode->UpdateNodeType(NodeToApply->getExtTypes(), TP);
+  }
+  case SDTCisVTSmallerThanOp: {
+    // The NodeToApply must be a leaf node that is a VT.  OtherOperandNum must
+    // have an integer type that is smaller than the VT.
+    if (!NodeToApply->isLeaf() ||
+        !dynamic_cast<DefInit*>(NodeToApply->getLeafValue()) ||
+        !static_cast<DefInit*>(NodeToApply->getLeafValue())->getDef()
+               ->isSubClassOf("ValueType"))
+      TP.error(N->getOperator()->getName() + " expects a VT operand!");
+    MVT::ValueType VT =
+     getValueType(static_cast<DefInit*>(NodeToApply->getLeafValue())->getDef());
+    if (!MVT::isInteger(VT))
+      TP.error(N->getOperator()->getName() + " VT operand must be integer!");
+    
+    TreePatternNode *OtherNode =
+      getOperandNum(x.SDTCisVTSmallerThanOp_Info.OtherOperandNum, N,NumResults);
+    
+    // It must be integer.
+    bool MadeChange = false;
+    MadeChange |= OtherNode->UpdateNodeType(MVT::isInt, TP);
+    
+    // This code only handles nodes that have one type set.  Assert here so
+    // that we can change this if we ever need to deal with multiple value
+    // types at this point.
+    assert(OtherNode->getExtTypes().size() == 1 && "Node has too many types!");
+    if (OtherNode->hasTypeSet() && OtherNode->getTypeNum(0) <= VT)
+      OtherNode->UpdateNodeType(MVT::Other, TP);  // Throw an error.
+    return false;
+  }
+  case SDTCisOpSmallerThanOp: {
+    TreePatternNode *BigOperand =
+      getOperandNum(x.SDTCisOpSmallerThanOp_Info.BigOperandNum, N, NumResults);
+
+    // Both operands must be integer or FP, but we don't care which.
+    bool MadeChange = false;
+    
+    // This code does not currently handle nodes which have multiple types,
+    // where some types are integer, and some are fp.  Assert that this is not
+    // the case.
+    assert(!(isExtIntegerInVTs(NodeToApply->getExtTypes()) &&
+             isExtFloatingPointInVTs(NodeToApply->getExtTypes())) &&
+           !(isExtIntegerInVTs(BigOperand->getExtTypes()) &&
+             isExtFloatingPointInVTs(BigOperand->getExtTypes())) &&
+           "SDTCisOpSmallerThanOp does not handle mixed int/fp types!");
+    if (isExtIntegerInVTs(NodeToApply->getExtTypes()))
+      MadeChange |= BigOperand->UpdateNodeType(MVT::isInt, TP);
+    else if (isExtFloatingPointInVTs(NodeToApply->getExtTypes()))
+      MadeChange |= BigOperand->UpdateNodeType(MVT::isFP, TP);
+    if (isExtIntegerInVTs(BigOperand->getExtTypes()))
+      MadeChange |= NodeToApply->UpdateNodeType(MVT::isInt, TP);
+    else if (isExtFloatingPointInVTs(BigOperand->getExtTypes()))
+      MadeChange |= NodeToApply->UpdateNodeType(MVT::isFP, TP);
+
+    std::vector<MVT::ValueType> VTs = CGT.getLegalValueTypes();
+    
+    if (isExtIntegerInVTs(NodeToApply->getExtTypes())) {
+      VTs = FilterVTs(VTs, MVT::isInteger);
+    } else if (isExtFloatingPointInVTs(NodeToApply->getExtTypes())) {
+      VTs = FilterVTs(VTs, MVT::isFloatingPoint);
+    } else {
+      VTs.clear();
+    }
+
+    switch (VTs.size()) {
+    default:         // Too many VT's to pick from.
+    case 0: break;   // No info yet.
+    case 1: 
+      // Only one VT of this flavor.  Cannot ever satisify the constraints.
+      return NodeToApply->UpdateNodeType(MVT::Other, TP);  // throw
+    case 2:
+      // If we have exactly two possible types, the little operand must be the
+      // small one, the big operand should be the big one.  Common with 
+      // float/double for example.
+      assert(VTs[0] < VTs[1] && "Should be sorted!");
+      MadeChange |= NodeToApply->UpdateNodeType(VTs[0], TP);
+      MadeChange |= BigOperand->UpdateNodeType(VTs[1], TP);
+      break;
+    }    
+    return MadeChange;
+  }
+  case SDTCisIntVectorOfSameSize: {
+    TreePatternNode *OtherOperand =
+      getOperandNum(x.SDTCisIntVectorOfSameSize_Info.OtherOperandNum,
+                    N, NumResults);
+    if (OtherOperand->hasTypeSet()) {
+      if (!MVT::isVector(OtherOperand->getTypeNum(0)))
+        TP.error(N->getOperator()->getName() + " VT operand must be a vector!");
+      MVT::ValueType IVT = OtherOperand->getTypeNum(0);
+      IVT = MVT::getIntVectorWithNumElements(MVT::getVectorNumElements(IVT));
+      return NodeToApply->UpdateNodeType(IVT, TP);
+    }
+    return false;
+  }
+  }  
+  return false;
+}
+
+
+//===----------------------------------------------------------------------===//
+// SDNodeInfo implementation
+//
+SDNodeInfo::SDNodeInfo(Record *R) : Def(R) {
+  EnumName    = R->getValueAsString("Opcode");
+  SDClassName = R->getValueAsString("SDClass");
+  Record *TypeProfile = R->getValueAsDef("TypeProfile");
+  NumResults = TypeProfile->getValueAsInt("NumResults");
+  NumOperands = TypeProfile->getValueAsInt("NumOperands");
+  
+  // Parse the properties.
+  Properties = 0;
+  std::vector<Record*> PropList = R->getValueAsListOfDefs("Properties");
+  for (unsigned i = 0, e = PropList.size(); i != e; ++i) {
+    if (PropList[i]->getName() == "SDNPCommutative") {
+      Properties |= 1 << SDNPCommutative;
+    } else if (PropList[i]->getName() == "SDNPAssociative") {
+      Properties |= 1 << SDNPAssociative;
+    } else if (PropList[i]->getName() == "SDNPHasChain") {
+      Properties |= 1 << SDNPHasChain;
+    } else if (PropList[i]->getName() == "SDNPOutFlag") {
+      Properties |= 1 << SDNPOutFlag;
+    } else if (PropList[i]->getName() == "SDNPInFlag") {
+      Properties |= 1 << SDNPInFlag;
+    } else if (PropList[i]->getName() == "SDNPOptInFlag") {
+      Properties |= 1 << SDNPOptInFlag;
+    } else {
+      cerr << "Unknown SD Node property '" << PropList[i]->getName()
+           << "' on node '" << R->getName() << "'!\n";
+      exit(1);
+    }
+  }
+  
+  
+  // Parse the type constraints.
+  std::vector<Record*> ConstraintList =
+    TypeProfile->getValueAsListOfDefs("Constraints");
+  TypeConstraints.assign(ConstraintList.begin(), ConstraintList.end());
+}
+
+//===----------------------------------------------------------------------===//
+// TreePatternNode implementation
+//
+
+TreePatternNode::~TreePatternNode() {
+#if 0 // FIXME: implement refcounted tree nodes!
+  for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
+    delete getChild(i);
+#endif
+}
+
+/// UpdateNodeType - Set the node type of N to VT if VT contains
+/// information.  If N already contains a conflicting type, then throw an
+/// exception.  This returns true if any information was updated.
+///
+bool TreePatternNode::UpdateNodeType(const std::vector<unsigned char> &ExtVTs,
+                                     TreePattern &TP) {
+  assert(!ExtVTs.empty() && "Cannot update node type with empty type vector!");
+  
+  if (ExtVTs[0] == MVT::isUnknown || LHSIsSubsetOfRHS(getExtTypes(), ExtVTs)) 
+    return false;
+  if (isTypeCompletelyUnknown() || LHSIsSubsetOfRHS(ExtVTs, getExtTypes())) {
+    setTypes(ExtVTs);
+    return true;
+  }
+
+  if (getExtTypeNum(0) == MVT::iPTR) {
+    if (ExtVTs[0] == MVT::iPTR || ExtVTs[0] == MVT::isInt)
+      return false;
+    if (isExtIntegerInVTs(ExtVTs)) {
+      std::vector<unsigned char> FVTs = FilterEVTs(ExtVTs, MVT::isInteger);
+      if (FVTs.size()) {
+        setTypes(ExtVTs);
+        return true;
+      }
+    }
+  }
+  
+  if (ExtVTs[0] == MVT::isInt && isExtIntegerInVTs(getExtTypes())) {
+    assert(hasTypeSet() && "should be handled above!");
+    std::vector<unsigned char> FVTs = FilterEVTs(getExtTypes(), MVT::isInteger);
+    if (getExtTypes() == FVTs)
+      return false;
+    setTypes(FVTs);
+    return true;
+  }
+  if (ExtVTs[0] == MVT::iPTR && isExtIntegerInVTs(getExtTypes())) {
+    //assert(hasTypeSet() && "should be handled above!");
+    std::vector<unsigned char> FVTs = FilterEVTs(getExtTypes(), MVT::isInteger);
+    if (getExtTypes() == FVTs)
+      return false;
+    if (FVTs.size()) {
+      setTypes(FVTs);
+      return true;
+    }
+  }      
+  if (ExtVTs[0] == MVT::isFP  && isExtFloatingPointInVTs(getExtTypes())) {
+    assert(hasTypeSet() && "should be handled above!");
+    std::vector<unsigned char> FVTs =
+      FilterEVTs(getExtTypes(), MVT::isFloatingPoint);
+    if (getExtTypes() == FVTs)
+      return false;
+    setTypes(FVTs);
+    return true;
+  }
+      
+  // If we know this is an int or fp type, and we are told it is a specific one,
+  // take the advice.
+  //
+  // Similarly, we should probably set the type here to the intersection of
+  // {isInt|isFP} and ExtVTs
+  if ((getExtTypeNum(0) == MVT::isInt && isExtIntegerInVTs(ExtVTs)) ||
+      (getExtTypeNum(0) == MVT::isFP  && isExtFloatingPointInVTs(ExtVTs))) {
+    setTypes(ExtVTs);
+    return true;
+  }
+  if (getExtTypeNum(0) == MVT::isInt && ExtVTs[0] == MVT::iPTR) {
+    setTypes(ExtVTs);
+    return true;
+  }
+
+  if (isLeaf()) {
+    dump();
+    cerr << " ";
+    TP.error("Type inference contradiction found in node!");
+  } else {
+    TP.error("Type inference contradiction found in node " + 
+             getOperator()->getName() + "!");
+  }
+  return true; // unreachable
+}
+
+
+void TreePatternNode::print(std::ostream &OS) const {
+  if (isLeaf()) {
+    OS << *getLeafValue();
+  } else {
+    OS << "(" << getOperator()->getName();
+  }
+  
+  // FIXME: At some point we should handle printing all the value types for 
+  // nodes that are multiply typed.
+  switch (getExtTypeNum(0)) {
+  case MVT::Other: OS << ":Other"; break;
+  case MVT::isInt: OS << ":isInt"; break;
+  case MVT::isFP : OS << ":isFP"; break;
+  case MVT::isUnknown: ; /*OS << ":?";*/ break;
+  case MVT::iPTR:  OS << ":iPTR"; break;
+  default: {
+    std::string VTName = llvm::getName(getTypeNum(0));
+    // Strip off MVT:: prefix if present.
+    if (VTName.substr(0,5) == "MVT::")
+      VTName = VTName.substr(5);
+    OS << ":" << VTName;
+    break;
+  }
+  }
+
+  if (!isLeaf()) {
+    if (getNumChildren() != 0) {
+      OS << " ";
+      getChild(0)->print(OS);
+      for (unsigned i = 1, e = getNumChildren(); i != e; ++i) {
+        OS << ", ";
+        getChild(i)->print(OS);
+      }
+    }
+    OS << ")";
+  }
+  
+  if (!PredicateFn.empty())
+    OS << "<<P:" << PredicateFn << ">>";
+  if (TransformFn)
+    OS << "<<X:" << TransformFn->getName() << ">>";
+  if (!getName().empty())
+    OS << ":$" << getName();
+
+}
+void TreePatternNode::dump() const {
+  print(*cerr.stream());
+}
+
+/// isIsomorphicTo - Return true if this node is recursively isomorphic to
+/// the specified node.  For this comparison, all of the state of the node
+/// is considered, except for the assigned name.  Nodes with differing names
+/// that are otherwise identical are considered isomorphic.
+bool TreePatternNode::isIsomorphicTo(const TreePatternNode *N) const {
+  if (N == this) return true;
+  if (N->isLeaf() != isLeaf() || getExtTypes() != N->getExtTypes() ||
+      getPredicateFn() != N->getPredicateFn() ||
+      getTransformFn() != N->getTransformFn())
+    return false;
+
+  if (isLeaf()) {
+    if (DefInit *DI = dynamic_cast<DefInit*>(getLeafValue()))
+      if (DefInit *NDI = dynamic_cast<DefInit*>(N->getLeafValue()))
+        return DI->getDef() == NDI->getDef();
+    return getLeafValue() == N->getLeafValue();
+  }
+  
+  if (N->getOperator() != getOperator() ||
+      N->getNumChildren() != getNumChildren()) return false;
+  for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
+    if (!getChild(i)->isIsomorphicTo(N->getChild(i)))
+      return false;
+  return true;
+}
+
+/// clone - Make a copy of this tree and all of its children.
+///
+TreePatternNode *TreePatternNode::clone() const {
+  TreePatternNode *New;
+  if (isLeaf()) {
+    New = new TreePatternNode(getLeafValue());
+  } else {
+    std::vector<TreePatternNode*> CChildren;
+    CChildren.reserve(Children.size());
+    for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
+      CChildren.push_back(getChild(i)->clone());
+    New = new TreePatternNode(getOperator(), CChildren);
+  }
+  New->setName(getName());
+  New->setTypes(getExtTypes());
+  New->setPredicateFn(getPredicateFn());
+  New->setTransformFn(getTransformFn());
+  return New;
+}
+
+/// SubstituteFormalArguments - Replace the formal arguments in this tree
+/// with actual values specified by ArgMap.
+void TreePatternNode::
+SubstituteFormalArguments(std::map<std::string, TreePatternNode*> &ArgMap) {
+  if (isLeaf()) return;
+  
+  for (unsigned i = 0, e = getNumChildren(); i != e; ++i) {
+    TreePatternNode *Child = getChild(i);
+    if (Child->isLeaf()) {
+      Init *Val = Child->getLeafValue();
+      if (dynamic_cast<DefInit*>(Val) &&
+          static_cast<DefInit*>(Val)->getDef()->getName() == "node") {
+        // We found a use of a formal argument, replace it with its value.
+        Child = ArgMap[Child->getName()];
+        assert(Child && "Couldn't find formal argument!");
+        setChild(i, Child);
+      }
+    } else {
+      getChild(i)->SubstituteFormalArguments(ArgMap);
+    }
+  }
+}
+
+
+/// InlinePatternFragments - If this pattern refers to any pattern
+/// fragments, inline them into place, giving us a pattern without any
+/// PatFrag references.
+TreePatternNode *TreePatternNode::InlinePatternFragments(TreePattern &TP) {
+  if (isLeaf()) return this;  // nothing to do.
+  Record *Op = getOperator();
+  
+  if (!Op->isSubClassOf("PatFrag")) {
+    // Just recursively inline children nodes.
+    for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
+      setChild(i, getChild(i)->InlinePatternFragments(TP));
+    return this;
+  }
+
+  // Otherwise, we found a reference to a fragment.  First, look up its
+  // TreePattern record.
+  TreePattern *Frag = TP.getDAGISelEmitter().getPatternFragment(Op);
+  
+  // Verify that we are passing the right number of operands.
+  if (Frag->getNumArgs() != Children.size())
+    TP.error("'" + Op->getName() + "' fragment requires " +
+             utostr(Frag->getNumArgs()) + " operands!");
+
+  TreePatternNode *FragTree = Frag->getOnlyTree()->clone();
+
+  // Resolve formal arguments to their actual value.
+  if (Frag->getNumArgs()) {
+    // Compute the map of formal to actual arguments.
+    std::map<std::string, TreePatternNode*> ArgMap;
+    for (unsigned i = 0, e = Frag->getNumArgs(); i != e; ++i)
+      ArgMap[Frag->getArgName(i)] = getChild(i)->InlinePatternFragments(TP);
+  
+    FragTree->SubstituteFormalArguments(ArgMap);
+  }
+  
+  FragTree->setName(getName());
+  FragTree->UpdateNodeType(getExtTypes(), TP);
+  
+  // Get a new copy of this fragment to stitch into here.
+  //delete this;    // FIXME: implement refcounting!
+  return FragTree;
+}
+
+/// getImplicitType - Check to see if the specified record has an implicit
+/// type which should be applied to it.  This infer the type of register
+/// references from the register file information, for example.
+///
+static std::vector<unsigned char> getImplicitType(Record *R, bool NotRegisters,
+                                      TreePattern &TP) {
+  // Some common return values
+  std::vector<unsigned char> Unknown(1, MVT::isUnknown);
+  std::vector<unsigned char> Other(1, MVT::Other);
+
+  // Check to see if this is a register or a register class...
+  if (R->isSubClassOf("RegisterClass")) {
+    if (NotRegisters) 
+      return Unknown;
+    const CodeGenRegisterClass &RC = 
+      TP.getDAGISelEmitter().getTargetInfo().getRegisterClass(R);
+    return ConvertVTs(RC.getValueTypes());
+  } else if (R->isSubClassOf("PatFrag")) {
+    // Pattern fragment types will be resolved when they are inlined.
+    return Unknown;
+  } else if (R->isSubClassOf("Register")) {
+    if (NotRegisters) 
+      return Unknown;
+    const CodeGenTarget &T = TP.getDAGISelEmitter().getTargetInfo();
+    return T.getRegisterVTs(R);
+  } else if (R->isSubClassOf("ValueType") || R->isSubClassOf("CondCode")) {
+    // Using a VTSDNode or CondCodeSDNode.
+    return Other;
+  } else if (R->isSubClassOf("ComplexPattern")) {
+    if (NotRegisters) 
+      return Unknown;
+    std::vector<unsigned char>
+    ComplexPat(1, TP.getDAGISelEmitter().getComplexPattern(R).getValueType());
+    return ComplexPat;
+  } else if (R->getName() == "ptr_rc") {
+    Other[0] = MVT::iPTR;
+    return Other;
+  } else if (R->getName() == "node" || R->getName() == "srcvalue" ||
+             R->getName() == "zero_reg") {
+    // Placeholder.
+    return Unknown;
+  }
+  
+  TP.error("Unknown node flavor used in pattern: " + R->getName());
+  return Other;
+}
+
+/// ApplyTypeConstraints - Apply all of the type constraints relevent to
+/// this node and its children in the tree.  This returns true if it makes a
+/// change, false otherwise.  If a type contradiction is found, throw an
+/// exception.
+bool TreePatternNode::ApplyTypeConstraints(TreePattern &TP, bool NotRegisters) {
+  DAGISelEmitter &ISE = TP.getDAGISelEmitter();
+  if (isLeaf()) {
+    if (DefInit *DI = dynamic_cast<DefInit*>(getLeafValue())) {
+      // If it's a regclass or something else known, include the type.
+      return UpdateNodeType(getImplicitType(DI->getDef(), NotRegisters, TP),TP);
+    } else if (IntInit *II = dynamic_cast<IntInit*>(getLeafValue())) {
+      // Int inits are always integers. :)
+      bool MadeChange = UpdateNodeType(MVT::isInt, TP);
+      
+      if (hasTypeSet()) {
+        // At some point, it may make sense for this tree pattern to have
+        // multiple types.  Assert here that it does not, so we revisit this
+        // code when appropriate.
+        assert(getExtTypes().size() >= 1 && "TreePattern doesn't have a type!");
+        MVT::ValueType VT = getTypeNum(0);
+        for (unsigned i = 1, e = getExtTypes().size(); i != e; ++i)
+          assert(getTypeNum(i) == VT && "TreePattern has too many types!");
+        
+        VT = getTypeNum(0);
+        if (VT != MVT::iPTR) {
+          unsigned Size = MVT::getSizeInBits(VT);
+          // Make sure that the value is representable for this type.
+          if (Size < 32) {
+            int Val = (II->getValue() << (32-Size)) >> (32-Size);
+            if (Val != II->getValue())
+              TP.error("Sign-extended integer value '" + itostr(II->getValue())+
+                       "' is out of range for type '" + 
+                       getEnumName(getTypeNum(0)) + "'!");
+          }
+        }
+      }
+      
+      return MadeChange;
+    }
+    return false;
+  }
+  
+  // special handling for set, which isn't really an SDNode.
+  if (getOperator()->getName() == "set") {
+    assert (getNumChildren() == 2 && "Only handle 2 operand set's for now!");
+    bool MadeChange = getChild(0)->ApplyTypeConstraints(TP, NotRegisters);
+    MadeChange |= getChild(1)->ApplyTypeConstraints(TP, NotRegisters);
+    
+    // Types of operands must match.
+    MadeChange |= getChild(0)->UpdateNodeType(getChild(1)->getExtTypes(), TP);
+    MadeChange |= getChild(1)->UpdateNodeType(getChild(0)->getExtTypes(), TP);
+    MadeChange |= UpdateNodeType(MVT::isVoid, TP);
+    return MadeChange;
+  } else if (getOperator() == ISE.get_intrinsic_void_sdnode() ||
+             getOperator() == ISE.get_intrinsic_w_chain_sdnode() ||
+             getOperator() == ISE.get_intrinsic_wo_chain_sdnode()) {
+    unsigned IID = 
+    dynamic_cast<IntInit*>(getChild(0)->getLeafValue())->getValue();
+    const CodeGenIntrinsic &Int = ISE.getIntrinsicInfo(IID);
+    bool MadeChange = false;
+    
+    // Apply the result type to the node.
+    MadeChange = UpdateNodeType(Int.ArgVTs[0], TP);
+    
+    if (getNumChildren() != Int.ArgVTs.size())
+      TP.error("Intrinsic '" + Int.Name + "' expects " +
+               utostr(Int.ArgVTs.size()-1) + " operands, not " +
+               utostr(getNumChildren()-1) + " operands!");
+
+    // Apply type info to the intrinsic ID.
+    MadeChange |= getChild(0)->UpdateNodeType(MVT::iPTR, TP);
+    
+    for (unsigned i = 1, e = getNumChildren(); i != e; ++i) {
+      MVT::ValueType OpVT = Int.ArgVTs[i];
+      MadeChange |= getChild(i)->UpdateNodeType(OpVT, TP);
+      MadeChange |= getChild(i)->ApplyTypeConstraints(TP, NotRegisters);
+    }
+    return MadeChange;
+  } else if (getOperator()->isSubClassOf("SDNode")) {
+    const SDNodeInfo &NI = ISE.getSDNodeInfo(getOperator());
+    
+    bool MadeChange = NI.ApplyTypeConstraints(this, TP);
+    for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
+      MadeChange |= getChild(i)->ApplyTypeConstraints(TP, NotRegisters);
+    // Branch, etc. do not produce results and top-level forms in instr pattern
+    // must have void types.
+    if (NI.getNumResults() == 0)
+      MadeChange |= UpdateNodeType(MVT::isVoid, TP);
+    
+    // If this is a vector_shuffle operation, apply types to the build_vector
+    // operation.  The types of the integers don't matter, but this ensures they
+    // won't get checked.
+    if (getOperator()->getName() == "vector_shuffle" &&
+        getChild(2)->getOperator()->getName() == "build_vector") {
+      TreePatternNode *BV = getChild(2);
+      const std::vector<MVT::ValueType> &LegalVTs
+        = ISE.getTargetInfo().getLegalValueTypes();
+      MVT::ValueType LegalIntVT = MVT::Other;
+      for (unsigned i = 0, e = LegalVTs.size(); i != e; ++i)
+        if (MVT::isInteger(LegalVTs[i]) && !MVT::isVector(LegalVTs[i])) {
+          LegalIntVT = LegalVTs[i];
+          break;
+        }
+      assert(LegalIntVT != MVT::Other && "No legal integer VT?");
+            
+      for (unsigned i = 0, e = BV->getNumChildren(); i != e; ++i)
+        MadeChange |= BV->getChild(i)->UpdateNodeType(LegalIntVT, TP);
+    }
+    return MadeChange;  
+  } else if (getOperator()->isSubClassOf("Instruction")) {
+    const DAGInstruction &Inst = ISE.getInstruction(getOperator());
+    bool MadeChange = false;
+    unsigned NumResults = Inst.getNumResults();
+    
+    assert(NumResults <= 1 &&
+           "Only supports zero or one result instrs!");
+
+    CodeGenInstruction &InstInfo =
+      ISE.getTargetInfo().getInstruction(getOperator()->getName());
+    // Apply the result type to the node
+    if (NumResults == 0 || InstInfo.noResults) { // FIXME: temporary hack.
+      MadeChange = UpdateNodeType(MVT::isVoid, TP);
+    } else {
+      Record *ResultNode = Inst.getResult(0);
+      
+      if (ResultNode->getName() == "ptr_rc") {
+        std::vector<unsigned char> VT;
+        VT.push_back(MVT::iPTR);
+        MadeChange = UpdateNodeType(VT, TP);
+      } else {
+        assert(ResultNode->isSubClassOf("RegisterClass") &&
+               "Operands should be register classes!");
+
+        const CodeGenRegisterClass &RC = 
+          ISE.getTargetInfo().getRegisterClass(ResultNode);
+        MadeChange = UpdateNodeType(ConvertVTs(RC.getValueTypes()), TP);
+      }
+    }
+
+    unsigned ChildNo = 0;
+    for (unsigned i = 0, e = Inst.getNumOperands(); i != e; ++i) {
+      Record *OperandNode = Inst.getOperand(i);
+      
+      // If the instruction expects a predicate or optional def operand, we
+      // codegen this by setting the operand to it's default value if it has a
+      // non-empty DefaultOps field.
+      if ((OperandNode->isSubClassOf("PredicateOperand") ||
+           OperandNode->isSubClassOf("OptionalDefOperand")) &&
+          !ISE.getDefaultOperand(OperandNode).DefaultOps.empty())
+        continue;
+       
+      // Verify that we didn't run out of provided operands.
+      if (ChildNo >= getNumChildren())
+        TP.error("Instruction '" + getOperator()->getName() +
+                 "' expects more operands than were provided.");
+      
+      MVT::ValueType VT;
+      TreePatternNode *Child = getChild(ChildNo++);
+      if (OperandNode->isSubClassOf("RegisterClass")) {
+        const CodeGenRegisterClass &RC = 
+          ISE.getTargetInfo().getRegisterClass(OperandNode);
+        MadeChange |= Child->UpdateNodeType(ConvertVTs(RC.getValueTypes()), TP);
+      } else if (OperandNode->isSubClassOf("Operand")) {
+        VT = getValueType(OperandNode->getValueAsDef("Type"));
+        MadeChange |= Child->UpdateNodeType(VT, TP);
+      } else if (OperandNode->getName() == "ptr_rc") {
+        MadeChange |= Child->UpdateNodeType(MVT::iPTR, TP);
+      } else {
+        assert(0 && "Unknown operand type!");
+        abort();
+      }
+      MadeChange |= Child->ApplyTypeConstraints(TP, NotRegisters);
+    }
+    
+    if (ChildNo != getNumChildren())
+      TP.error("Instruction '" + getOperator()->getName() +
+               "' was provided too many operands!");
+    
+    return MadeChange;
+  } else {
+    assert(getOperator()->isSubClassOf("SDNodeXForm") && "Unknown node type!");
+    
+    // Node transforms always take one operand.
+    if (getNumChildren() != 1)
+      TP.error("Node transform '" + getOperator()->getName() +
+               "' requires one operand!");
+
+    // If either the output or input of the xform does not have exact
+    // type info. We assume they must be the same. Otherwise, it is perfectly
+    // legal to transform from one type to a completely different type.
+    if (!hasTypeSet() || !getChild(0)->hasTypeSet()) {
+      bool MadeChange = UpdateNodeType(getChild(0)->getExtTypes(), TP);
+      MadeChange |= getChild(0)->UpdateNodeType(getExtTypes(), TP);
+      return MadeChange;
+    }
+    return false;
+  }
+}
+
+/// OnlyOnRHSOfCommutative - Return true if this value is only allowed on the
+/// RHS of a commutative operation, not the on LHS.
+static bool OnlyOnRHSOfCommutative(TreePatternNode *N) {
+  if (!N->isLeaf() && N->getOperator()->getName() == "imm")
+    return true;
+  if (N->isLeaf() && dynamic_cast<IntInit*>(N->getLeafValue()))
+    return true;
+  return false;
+}
+
+
+/// canPatternMatch - If it is impossible for this pattern to match on this
+/// target, fill in Reason and return false.  Otherwise, return true.  This is
+/// used as a santity check for .td files (to prevent people from writing stuff
+/// that can never possibly work), and to prevent the pattern permuter from
+/// generating stuff that is useless.
+bool TreePatternNode::canPatternMatch(std::string &Reason, DAGISelEmitter &ISE){
+  if (isLeaf()) return true;
+
+  for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
+    if (!getChild(i)->canPatternMatch(Reason, ISE))
+      return false;
+
+  // If this is an intrinsic, handle cases that would make it not match.  For
+  // example, if an operand is required to be an immediate.
+  if (getOperator()->isSubClassOf("Intrinsic")) {
+    // TODO:
+    return true;
+  }
+  
+  // If this node is a commutative operator, check that the LHS isn't an
+  // immediate.
+  const SDNodeInfo &NodeInfo = ISE.getSDNodeInfo(getOperator());
+  if (NodeInfo.hasProperty(SDNPCommutative)) {
+    // Scan all of the operands of the node and make sure that only the last one
+    // is a constant node, unless the RHS also is.
+    if (!OnlyOnRHSOfCommutative(getChild(getNumChildren()-1))) {
+      for (unsigned i = 0, e = getNumChildren()-1; i != e; ++i)
+        if (OnlyOnRHSOfCommutative(getChild(i))) {
+          Reason="Immediate value must be on the RHS of commutative operators!";
+          return false;
+        }
+    }
+  }
+  
+  return true;
+}
+
+//===----------------------------------------------------------------------===//
+// TreePattern implementation
+//
+
+TreePattern::TreePattern(Record *TheRec, ListInit *RawPat, bool isInput,
+                         DAGISelEmitter &ise) : TheRecord(TheRec), ISE(ise) {
+   isInputPattern = isInput;
+   for (unsigned i = 0, e = RawPat->getSize(); i != e; ++i)
+     Trees.push_back(ParseTreePattern((DagInit*)RawPat->getElement(i)));
+}
+
+TreePattern::TreePattern(Record *TheRec, DagInit *Pat, bool isInput,
+                         DAGISelEmitter &ise) : TheRecord(TheRec), ISE(ise) {
+  isInputPattern = isInput;
+  Trees.push_back(ParseTreePattern(Pat));
+}
+
+TreePattern::TreePattern(Record *TheRec, TreePatternNode *Pat, bool isInput,
+                         DAGISelEmitter &ise) : TheRecord(TheRec), ISE(ise) {
+  isInputPattern = isInput;
+  Trees.push_back(Pat);
+}
+
+
+
+void TreePattern::error(const std::string &Msg) const {
+  dump();
+  throw "In " + TheRecord->getName() + ": " + Msg;
+}
+
+TreePatternNode *TreePattern::ParseTreePattern(DagInit *Dag) {
+  DefInit *OpDef = dynamic_cast<DefInit*>(Dag->getOperator());
+  if (!OpDef) error("Pattern has unexpected operator type!");
+  Record *Operator = OpDef->getDef();
+  
+  if (Operator->isSubClassOf("ValueType")) {
+    // If the operator is a ValueType, then this must be "type cast" of a leaf
+    // node.
+    if (Dag->getNumArgs() != 1)
+      error("Type cast only takes one operand!");
+    
+    Init *Arg = Dag->getArg(0);
+    TreePatternNode *New;
+    if (DefInit *DI = dynamic_cast<DefInit*>(Arg)) {
+      Record *R = DI->getDef();
+      if (R->isSubClassOf("SDNode") || R->isSubClassOf("PatFrag")) {
+        Dag->setArg(0, new DagInit(DI,
+                                std::vector<std::pair<Init*, std::string> >()));
+        return ParseTreePattern(Dag);
+      }
+      New = new TreePatternNode(DI);
+    } else if (DagInit *DI = dynamic_cast<DagInit*>(Arg)) {
+      New = ParseTreePattern(DI);
+    } else if (IntInit *II = dynamic_cast<IntInit*>(Arg)) {
+      New = new TreePatternNode(II);
+      if (!Dag->getArgName(0).empty())
+        error("Constant int argument should not have a name!");
+    } else if (BitsInit *BI = dynamic_cast<BitsInit*>(Arg)) {
+      // Turn this into an IntInit.
+      Init *II = BI->convertInitializerTo(new IntRecTy());
+      if (II == 0 || !dynamic_cast<IntInit*>(II))
+        error("Bits value must be constants!");
+      
+      New = new TreePatternNode(dynamic_cast<IntInit*>(II));
+      if (!Dag->getArgName(0).empty())
+        error("Constant int argument should not have a name!");
+    } else {
+      Arg->dump();
+      error("Unknown leaf value for tree pattern!");
+      return 0;
+    }
+    
+    // Apply the type cast.
+    New->UpdateNodeType(getValueType(Operator), *this);
+    New->setName(Dag->getArgName(0));
+    return New;
+  }
+  
+  // Verify that this is something that makes sense for an operator.
+  if (!Operator->isSubClassOf("PatFrag") && !Operator->isSubClassOf("SDNode") &&
+      !Operator->isSubClassOf("Instruction") && 
+      !Operator->isSubClassOf("SDNodeXForm") &&
+      !Operator->isSubClassOf("Intrinsic") &&
+      Operator->getName() != "set")
+    error("Unrecognized node '" + Operator->getName() + "'!");
+  
+  //  Check to see if this is something that is illegal in an input pattern.
+  if (isInputPattern && (Operator->isSubClassOf("Instruction") ||
+                         Operator->isSubClassOf("SDNodeXForm")))
+    error("Cannot use '" + Operator->getName() + "' in an input pattern!");
+  
+  std::vector<TreePatternNode*> Children;
+  
+  for (unsigned i = 0, e = Dag->getNumArgs(); i != e; ++i) {
+    Init *Arg = Dag->getArg(i);
+    if (DagInit *DI = dynamic_cast<DagInit*>(Arg)) {
+      Children.push_back(ParseTreePattern(DI));
+      if (Children.back()->getName().empty())
+        Children.back()->setName(Dag->getArgName(i));
+    } else if (DefInit *DefI = dynamic_cast<DefInit*>(Arg)) {
+      Record *R = DefI->getDef();
+      // Direct reference to a leaf DagNode or PatFrag?  Turn it into a
+      // TreePatternNode if its own.
+      if (R->isSubClassOf("SDNode") || R->isSubClassOf("PatFrag")) {
+        Dag->setArg(i, new DagInit(DefI,
+                              std::vector<std::pair<Init*, std::string> >()));
+        --i;  // Revisit this node...
+      } else {
+        TreePatternNode *Node = new TreePatternNode(DefI);
+        Node->setName(Dag->getArgName(i));
+        Children.push_back(Node);
+        
+        // Input argument?
+        if (R->getName() == "node") {
+          if (Dag->getArgName(i).empty())
+            error("'node' argument requires a name to match with operand list");
+          Args.push_back(Dag->getArgName(i));
+        }
+      }
+    } else if (IntInit *II = dynamic_cast<IntInit*>(Arg)) {
+      TreePatternNode *Node = new TreePatternNode(II);
+      if (!Dag->getArgName(i).empty())
+        error("Constant int argument should not have a name!");
+      Children.push_back(Node);
+    } else if (BitsInit *BI = dynamic_cast<BitsInit*>(Arg)) {
+      // Turn this into an IntInit.
+      Init *II = BI->convertInitializerTo(new IntRecTy());
+      if (II == 0 || !dynamic_cast<IntInit*>(II))
+        error("Bits value must be constants!");
+      
+      TreePatternNode *Node = new TreePatternNode(dynamic_cast<IntInit*>(II));
+      if (!Dag->getArgName(i).empty())
+        error("Constant int argument should not have a name!");
+      Children.push_back(Node);
+    } else {
+      cerr << '"';
+      Arg->dump();
+      cerr << "\": ";
+      error("Unknown leaf value for tree pattern!");
+    }
+  }
+  
+  // If the operator is an intrinsic, then this is just syntactic sugar for for
+  // (intrinsic_* <number>, ..children..).  Pick the right intrinsic node, and 
+  // convert the intrinsic name to a number.
+  if (Operator->isSubClassOf("Intrinsic")) {
+    const CodeGenIntrinsic &Int = getDAGISelEmitter().getIntrinsic(Operator);
+    unsigned IID = getDAGISelEmitter().getIntrinsicID(Operator)+1;
+
+    // If this intrinsic returns void, it must have side-effects and thus a
+    // chain.
+    if (Int.ArgVTs[0] == MVT::isVoid) {
+      Operator = getDAGISelEmitter().get_intrinsic_void_sdnode();
+    } else if (Int.ModRef != CodeGenIntrinsic::NoMem) {
+      // Has side-effects, requires chain.
+      Operator = getDAGISelEmitter().get_intrinsic_w_chain_sdnode();
+    } else {
+      // Otherwise, no chain.
+      Operator = getDAGISelEmitter().get_intrinsic_wo_chain_sdnode();
+    }
+    
+    TreePatternNode *IIDNode = new TreePatternNode(new IntInit(IID));
+    Children.insert(Children.begin(), IIDNode);
+  }
+  
+  return new TreePatternNode(Operator, Children);
+}
+
+/// InferAllTypes - Infer/propagate as many types throughout the expression
+/// patterns as possible.  Return true if all types are infered, false
+/// otherwise.  Throw an exception if a type contradiction is found.
+bool TreePattern::InferAllTypes() {
+  bool MadeChange = true;
+  while (MadeChange) {
+    MadeChange = false;
+    for (unsigned i = 0, e = Trees.size(); i != e; ++i)
+      MadeChange |= Trees[i]->ApplyTypeConstraints(*this, false);
+  }
+  
+  bool HasUnresolvedTypes = false;
+  for (unsigned i = 0, e = Trees.size(); i != e; ++i)
+    HasUnresolvedTypes |= Trees[i]->ContainsUnresolvedType();
+  return !HasUnresolvedTypes;
+}
+
+void TreePattern::print(std::ostream &OS) const {
+  OS << getRecord()->getName();
+  if (!Args.empty()) {
+    OS << "(" << Args[0];
+    for (unsigned i = 1, e = Args.size(); i != e; ++i)
+      OS << ", " << Args[i];
+    OS << ")";
+  }
+  OS << ": ";
+  
+  if (Trees.size() > 1)
+    OS << "[\n";
+  for (unsigned i = 0, e = Trees.size(); i != e; ++i) {
+    OS << "\t";
+    Trees[i]->print(OS);
+    OS << "\n";
+  }
+
+  if (Trees.size() > 1)
+    OS << "]\n";
+}
+
+void TreePattern::dump() const { print(*cerr.stream()); }
+
+
+
+//===----------------------------------------------------------------------===//
+// DAGISelEmitter implementation
+//
+
+// Parse all of the SDNode definitions for the target, populating SDNodes.
+void DAGISelEmitter::ParseNodeInfo() {
+  std::vector<Record*> Nodes = Records.getAllDerivedDefinitions("SDNode");
+  while (!Nodes.empty()) {
+    SDNodes.insert(std::make_pair(Nodes.back(), Nodes.back()));
+    Nodes.pop_back();
+  }
+
+  // Get the buildin intrinsic nodes.
+  intrinsic_void_sdnode     = getSDNodeNamed("intrinsic_void");
+  intrinsic_w_chain_sdnode  = getSDNodeNamed("intrinsic_w_chain");
+  intrinsic_wo_chain_sdnode = getSDNodeNamed("intrinsic_wo_chain");
+}
+
+/// ParseNodeTransforms - Parse all SDNodeXForm instances into the SDNodeXForms
+/// map, and emit them to the file as functions.
+void DAGISelEmitter::ParseNodeTransforms(std::ostream &OS) {
+  OS << "\n// Node transformations.\n";
+  std::vector<Record*> Xforms = Records.getAllDerivedDefinitions("SDNodeXForm");
+  while (!Xforms.empty()) {
+    Record *XFormNode = Xforms.back();
+    Record *SDNode = XFormNode->getValueAsDef("Opcode");
+    std::string Code = XFormNode->getValueAsCode("XFormFunction");
+    SDNodeXForms.insert(std::make_pair(XFormNode,
+                                       std::make_pair(SDNode, Code)));
+
+    if (!Code.empty()) {
+      std::string ClassName = getSDNodeInfo(SDNode).getSDClassName();
+      const char *C2 = ClassName == "SDNode" ? "N" : "inN";
+
+      OS << "inline SDOperand Transform_" << XFormNode->getName()
+         << "(SDNode *" << C2 << ") {\n";
+      if (ClassName != "SDNode")
+        OS << "  " << ClassName << " *N = cast<" << ClassName << ">(inN);\n";
+      OS << Code << "\n}\n";
+    }
+
+    Xforms.pop_back();
+  }
+}
+
+void DAGISelEmitter::ParseComplexPatterns() {
+  std::vector<Record*> AMs = Records.getAllDerivedDefinitions("ComplexPattern");
+  while (!AMs.empty()) {
+    ComplexPatterns.insert(std::make_pair(AMs.back(), AMs.back()));
+    AMs.pop_back();
+  }
+}
+
+
+/// ParsePatternFragments - Parse all of the PatFrag definitions in the .td
+/// file, building up the PatternFragments map.  After we've collected them all,
+/// inline fragments together as necessary, so that there are no references left
+/// inside a pattern fragment to a pattern fragment.
+///
+/// This also emits all of the predicate functions to the output file.
+///
+void DAGISelEmitter::ParsePatternFragments(std::ostream &OS) {
+  std::vector<Record*> Fragments = Records.getAllDerivedDefinitions("PatFrag");
+  
+  // First step, parse all of the fragments and emit predicate functions.
+  OS << "\n// Predicate functions.\n";
+  for (unsigned i = 0, e = Fragments.size(); i != e; ++i) {
+    DagInit *Tree = Fragments[i]->getValueAsDag("Fragment");
+    TreePattern *P = new TreePattern(Fragments[i], Tree, true, *this);
+    PatternFragments[Fragments[i]] = P;
+    
+    // Validate the argument list, converting it to map, to discard duplicates.
+    std::vector<std::string> &Args = P->getArgList();
+    std::set<std::string> OperandsMap(Args.begin(), Args.end());
+    
+    if (OperandsMap.count(""))
+      P->error("Cannot have unnamed 'node' values in pattern fragment!");
+    
+    // Parse the operands list.
+    DagInit *OpsList = Fragments[i]->getValueAsDag("Operands");
+    DefInit *OpsOp = dynamic_cast<DefInit*>(OpsList->getOperator());
+    if (!OpsOp || OpsOp->getDef()->getName() != "ops")
+      P->error("Operands list should start with '(ops ... '!");
+    
+    // Copy over the arguments.       
+    Args.clear();
+    for (unsigned j = 0, e = OpsList->getNumArgs(); j != e; ++j) {
+      if (!dynamic_cast<DefInit*>(OpsList->getArg(j)) ||
+          static_cast<DefInit*>(OpsList->getArg(j))->
+          getDef()->getName() != "node")
+        P->error("Operands list should all be 'node' values.");
+      if (OpsList->getArgName(j).empty())
+        P->error("Operands list should have names for each operand!");
+      if (!OperandsMap.count(OpsList->getArgName(j)))
+        P->error("'" + OpsList->getArgName(j) +
+                 "' does not occur in pattern or was multiply specified!");
+      OperandsMap.erase(OpsList->getArgName(j));
+      Args.push_back(OpsList->getArgName(j));
+    }
+    
+    if (!OperandsMap.empty())
+      P->error("Operands list does not contain an entry for operand '" +
+               *OperandsMap.begin() + "'!");
+
+    // If there is a code init for this fragment, emit the predicate code and
+    // keep track of the fact that this fragment uses it.
+    std::string Code = Fragments[i]->getValueAsCode("Predicate");
+    if (!Code.empty()) {
+      if (P->getOnlyTree()->isLeaf())
+        OS << "inline bool Predicate_" << Fragments[i]->getName()
+           << "(SDNode *N) {\n";
+      else {
+        std::string ClassName =
+          getSDNodeInfo(P->getOnlyTree()->getOperator()).getSDClassName();
+        const char *C2 = ClassName == "SDNode" ? "N" : "inN";
+      
+        OS << "inline bool Predicate_" << Fragments[i]->getName()
+           << "(SDNode *" << C2 << ") {\n";
+        if (ClassName != "SDNode")
+          OS << "  " << ClassName << " *N = cast<" << ClassName << ">(inN);\n";
+      }
+      OS << Code << "\n}\n";
+      P->getOnlyTree()->setPredicateFn("Predicate_"+Fragments[i]->getName());
+    }
+    
+    // If there is a node transformation corresponding to this, keep track of
+    // it.
+    Record *Transform = Fragments[i]->getValueAsDef("OperandTransform");
+    if (!getSDNodeTransform(Transform).second.empty())    // not noop xform?
+      P->getOnlyTree()->setTransformFn(Transform);
+  }
+  
+  OS << "\n\n";
+
+  // Now that we've parsed all of the tree fragments, do a closure on them so
+  // that there are not references to PatFrags left inside of them.
+  for (std::map<Record*, TreePattern*>::iterator I = PatternFragments.begin(),
+       E = PatternFragments.end(); I != E; ++I) {
+    TreePattern *ThePat = I->second;
+    ThePat->InlinePatternFragments();
+        
+    // Infer as many types as possible.  Don't worry about it if we don't infer
+    // all of them, some may depend on the inputs of the pattern.
+    try {
+      ThePat->InferAllTypes();
+    } catch (...) {
+      // If this pattern fragment is not supported by this target (no types can
+      // satisfy its constraints), just ignore it.  If the bogus pattern is
+      // actually used by instructions, the type consistency error will be
+      // reported there.
+    }
+    
+    // If debugging, print out the pattern fragment result.
+    DEBUG(ThePat->dump());
+  }
+}
+
+void DAGISelEmitter::ParseDefaultOperands() {
+  std::vector<Record*> DefaultOps[2];
+  DefaultOps[0] = Records.getAllDerivedDefinitions("PredicateOperand");
+  DefaultOps[1] = Records.getAllDerivedDefinitions("OptionalDefOperand");
+
+  // Find some SDNode.
+  assert(!SDNodes.empty() && "No SDNodes parsed?");
+  Init *SomeSDNode = new DefInit(SDNodes.begin()->first);
+  
+  for (unsigned iter = 0; iter != 2; ++iter) {
+    for (unsigned i = 0, e = DefaultOps[iter].size(); i != e; ++i) {
+      DagInit *DefaultInfo = DefaultOps[iter][i]->getValueAsDag("DefaultOps");
+    
+      // Clone the DefaultInfo dag node, changing the operator from 'ops' to
+      // SomeSDnode so that we can parse this.
+      std::vector<std::pair<Init*, std::string> > Ops;
+      for (unsigned op = 0, e = DefaultInfo->getNumArgs(); op != e; ++op)
+        Ops.push_back(std::make_pair(DefaultInfo->getArg(op),
+                                     DefaultInfo->getArgName(op)));
+      DagInit *DI = new DagInit(SomeSDNode, Ops);
+    
+      // Create a TreePattern to parse this.
+      TreePattern P(DefaultOps[iter][i], DI, false, *this);
+      assert(P.getNumTrees() == 1 && "This ctor can only produce one tree!");
+
+      // Copy the operands over into a DAGDefaultOperand.
+      DAGDefaultOperand DefaultOpInfo;
+    
+      TreePatternNode *T = P.getTree(0);
+      for (unsigned op = 0, e = T->getNumChildren(); op != e; ++op) {
+        TreePatternNode *TPN = T->getChild(op);
+        while (TPN->ApplyTypeConstraints(P, false))
+          /* Resolve all types */;
+      
+        if (TPN->ContainsUnresolvedType())
+          if (iter == 0)
+            throw "Value #" + utostr(i) + " of PredicateOperand '" +
+              DefaultOps[iter][i]->getName() + "' doesn't have a concrete type!";
+          else
+            throw "Value #" + utostr(i) + " of OptionalDefOperand '" +
+              DefaultOps[iter][i]->getName() + "' doesn't have a concrete type!";
+      
+        DefaultOpInfo.DefaultOps.push_back(TPN);
+      }
+
+      // Insert it into the DefaultOperands map so we can find it later.
+      DefaultOperands[DefaultOps[iter][i]] = DefaultOpInfo;
+    }
+  }
+}
+
+/// HandleUse - Given "Pat" a leaf in the pattern, check to see if it is an
+/// instruction input.  Return true if this is a real use.
+static bool HandleUse(TreePattern *I, TreePatternNode *Pat,
+                      std::map<std::string, TreePatternNode*> &InstInputs,
+                      std::vector<Record*> &InstImpInputs) {
+  // No name -> not interesting.
+  if (Pat->getName().empty()) {
+    if (Pat->isLeaf()) {
+      DefInit *DI = dynamic_cast<DefInit*>(Pat->getLeafValue());
+      if (DI && DI->getDef()->isSubClassOf("RegisterClass"))
+        I->error("Input " + DI->getDef()->getName() + " must be named!");
+      else if (DI && DI->getDef()->isSubClassOf("Register")) 
+        InstImpInputs.push_back(DI->getDef());
+    }
+    return false;
+  }
+
+  Record *Rec;
+  if (Pat->isLeaf()) {
+    DefInit *DI = dynamic_cast<DefInit*>(Pat->getLeafValue());
+    if (!DI) I->error("Input $" + Pat->getName() + " must be an identifier!");
+    Rec = DI->getDef();
+  } else {
+    assert(Pat->getNumChildren() == 0 && "can't be a use with children!");
+    Rec = Pat->getOperator();
+  }
+
+  // SRCVALUE nodes are ignored.
+  if (Rec->getName() == "srcvalue")
+    return false;
+
+  TreePatternNode *&Slot = InstInputs[Pat->getName()];
+  if (!Slot) {
+    Slot = Pat;
+  } else {
+    Record *SlotRec;
+    if (Slot->isLeaf()) {
+      SlotRec = dynamic_cast<DefInit*>(Slot->getLeafValue())->getDef();
+    } else {
+      assert(Slot->getNumChildren() == 0 && "can't be a use with children!");
+      SlotRec = Slot->getOperator();
+    }
+    
+    // Ensure that the inputs agree if we've already seen this input.
+    if (Rec != SlotRec)
+      I->error("All $" + Pat->getName() + " inputs must agree with each other");
+    if (Slot->getExtTypes() != Pat->getExtTypes())
+      I->error("All $" + Pat->getName() + " inputs must agree with each other");
+  }
+  return true;
+}
+
+/// FindPatternInputsAndOutputs - Scan the specified TreePatternNode (which is
+/// part of "I", the instruction), computing the set of inputs and outputs of
+/// the pattern.  Report errors if we see anything naughty.
+void DAGISelEmitter::
+FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
+                            std::map<std::string, TreePatternNode*> &InstInputs,
+                            std::map<std::string, TreePatternNode*>&InstResults,
+                            std::vector<Record*> &InstImpInputs,
+                            std::vector<Record*> &InstImpResults) {
+  if (Pat->isLeaf()) {
+    bool isUse = HandleUse(I, Pat, InstInputs, InstImpInputs);
+    if (!isUse && Pat->getTransformFn())
+      I->error("Cannot specify a transform function for a non-input value!");
+    return;
+  } else if (Pat->getOperator()->getName() != "set") {
+    // If this is not a set, verify that the children nodes are not void typed,
+    // and recurse.
+    for (unsigned i = 0, e = Pat->getNumChildren(); i != e; ++i) {
+      if (Pat->getChild(i)->getExtTypeNum(0) == MVT::isVoid)
+        I->error("Cannot have void nodes inside of patterns!");
+      FindPatternInputsAndOutputs(I, Pat->getChild(i), InstInputs, InstResults,
+                                  InstImpInputs, InstImpResults);
+    }
+    
+    // If this is a non-leaf node with no children, treat it basically as if
+    // it were a leaf.  This handles nodes like (imm).
+    bool isUse = false;
+    if (Pat->getNumChildren() == 0)
+      isUse = HandleUse(I, Pat, InstInputs, InstImpInputs);
+    
+    if (!isUse && Pat->getTransformFn())
+      I->error("Cannot specify a transform function for a non-input value!");
+    return;
+  } 
+  
+  // Otherwise, this is a set, validate and collect instruction results.
+  if (Pat->getNumChildren() == 0)
+    I->error("set requires operands!");
+  else if (Pat->getNumChildren() & 1)
+    I->error("set requires an even number of operands");
+  
+  if (Pat->getTransformFn())
+    I->error("Cannot specify a transform function on a set node!");
+  
+  // Check the set destinations.
+  unsigned NumValues = Pat->getNumChildren()/2;
+  for (unsigned i = 0; i != NumValues; ++i) {
+    TreePatternNode *Dest = Pat->getChild(i);
+    if (!Dest->isLeaf())
+      I->error("set destination should be a register!");
+    
+    DefInit *Val = dynamic_cast<DefInit*>(Dest->getLeafValue());
+    if (!Val)
+      I->error("set destination should be a register!");
+
+    if (Val->getDef()->isSubClassOf("RegisterClass") ||
+        Val->getDef()->getName() == "ptr_rc") {
+      if (Dest->getName().empty())
+        I->error("set destination must have a name!");
+      if (InstResults.count(Dest->getName()))
+        I->error("cannot set '" + Dest->getName() +"' multiple times");
+      InstResults[Dest->getName()] = Dest;
+    } else if (Val->getDef()->isSubClassOf("Register")) {
+      InstImpResults.push_back(Val->getDef());
+    } else {
+      I->error("set destination should be a register!");
+    }
+    
+    // Verify and collect info from the computation.
+    FindPatternInputsAndOutputs(I, Pat->getChild(i+NumValues),
+                                InstInputs, InstResults,
+                                InstImpInputs, InstImpResults);
+  }
+}
+
+/// ParseInstructions - Parse all of the instructions, inlining and resolving
+/// any fragments involved.  This populates the Instructions list with fully
+/// resolved instructions.
+void DAGISelEmitter::ParseInstructions() {
+  std::vector<Record*> Instrs = Records.getAllDerivedDefinitions("Instruction");
+  
+  for (unsigned i = 0, e = Instrs.size(); i != e; ++i) {
+    ListInit *LI = 0;
+    
+    if (dynamic_cast<ListInit*>(Instrs[i]->getValueInit("Pattern")))
+      LI = Instrs[i]->getValueAsListInit("Pattern");
+    
+    // If there is no pattern, only collect minimal information about the
+    // instruction for its operand list.  We have to assume that there is one
+    // result, as we have no detailed info.
+    if (!LI || LI->getSize() == 0) {
+      std::vector<Record*> Results;
+      std::vector<Record*> Operands;
+      
+      CodeGenInstruction &InstInfo =Target.getInstruction(Instrs[i]->getName());
+
+      if (InstInfo.OperandList.size() != 0) {
+        // FIXME: temporary hack...
+        if (InstInfo.noResults) {
+          // These produce no results
+          for (unsigned j = 0, e = InstInfo.OperandList.size(); j < e; ++j)
+            Operands.push_back(InstInfo.OperandList[j].Rec);
+        } else {
+          // Assume the first operand is the result.
+          Results.push_back(InstInfo.OperandList[0].Rec);
+      
+          // The rest are inputs.
+          for (unsigned j = 1, e = InstInfo.OperandList.size(); j < e; ++j)
+            Operands.push_back(InstInfo.OperandList[j].Rec);
+        }
+      }
+      
+      // Create and insert the instruction.
+      std::vector<Record*> ImpResults;
+      std::vector<Record*> ImpOperands;
+      Instructions.insert(std::make_pair(Instrs[i], 
+                          DAGInstruction(0, Results, Operands, ImpResults,
+                                         ImpOperands)));
+      continue;  // no pattern.
+    }
+    
+    // Parse the instruction.
+    TreePattern *I = new TreePattern(Instrs[i], LI, true, *this);
+    // Inline pattern fragments into it.
+    I->InlinePatternFragments();
+    
+    // Infer as many types as possible.  If we cannot infer all of them, we can
+    // never do anything with this instruction pattern: report it to the user.
+    if (!I->InferAllTypes())
+      I->error("Could not infer all types in pattern!");
+    
+    // InstInputs - Keep track of all of the inputs of the instruction, along 
+    // with the record they are declared as.
+    std::map<std::string, TreePatternNode*> InstInputs;
+    
+    // InstResults - Keep track of all the virtual registers that are 'set'
+    // in the instruction, including what reg class they are.
+    std::map<std::string, TreePatternNode*> InstResults;
+
+    std::vector<Record*> InstImpInputs;
+    std::vector<Record*> InstImpResults;
+    
+    // Verify that the top-level forms in the instruction are of void type, and
+    // fill in the InstResults map.
+    for (unsigned j = 0, e = I->getNumTrees(); j != e; ++j) {
+      TreePatternNode *Pat = I->getTree(j);
+      if (Pat->getExtTypeNum(0) != MVT::isVoid)
+        I->error("Top-level forms in instruction pattern should have"
+                 " void types");
+
+      // Find inputs and outputs, and verify the structure of the uses/defs.
+      FindPatternInputsAndOutputs(I, Pat, InstInputs, InstResults,
+                                  InstImpInputs, InstImpResults);
+    }
+
+    // Now that we have inputs and outputs of the pattern, inspect the operands
+    // list for the instruction.  This determines the order that operands are
+    // added to the machine instruction the node corresponds to.
+    unsigned NumResults = InstResults.size();
+
+    // Parse the operands list from the (ops) list, validating it.
+    assert(I->getArgList().empty() && "Args list should still be empty here!");
+    CodeGenInstruction &CGI = Target.getInstruction(Instrs[i]->getName());
+
+    // Check that all of the results occur first in the list.
+    std::vector<Record*> Results;
+    TreePatternNode *Res0Node = NULL;
+    for (unsigned i = 0; i != NumResults; ++i) {
+      if (i == CGI.OperandList.size())
+        I->error("'" + InstResults.begin()->first +
+                 "' set but does not appear in operand list!");
+      const std::string &OpName = CGI.OperandList[i].Name;
+      
+      // Check that it exists in InstResults.
+      TreePatternNode *RNode = InstResults[OpName];
+      if (RNode == 0)
+        I->error("Operand $" + OpName + " does not exist in operand list!");
+        
+      if (i == 0)
+        Res0Node = RNode;
+      Record *R = dynamic_cast<DefInit*>(RNode->getLeafValue())->getDef();
+      if (R == 0)
+        I->error("Operand $" + OpName + " should be a set destination: all "
+                 "outputs must occur before inputs in operand list!");
+      
+      if (CGI.OperandList[i].Rec != R)
+        I->error("Operand $" + OpName + " class mismatch!");
+      
+      // Remember the return type.
+      Results.push_back(CGI.OperandList[i].Rec);
+      
+      // Okay, this one checks out.
+      InstResults.erase(OpName);
+    }
+
+    // Loop over the inputs next.  Make a copy of InstInputs so we can destroy
+    // the copy while we're checking the inputs.
+    std::map<std::string, TreePatternNode*> InstInputsCheck(InstInputs);
+
+    std::vector<TreePatternNode*> ResultNodeOperands;
+    std::vector<Record*> Operands;
+    for (unsigned i = NumResults, e = CGI.OperandList.size(); i != e; ++i) {
+      CodeGenInstruction::OperandInfo &Op = CGI.OperandList[i];
+      const std::string &OpName = Op.Name;
+      if (OpName.empty())
+        I->error("Operand #" + utostr(i) + " in operands list has no name!");
+
+      if (!InstInputsCheck.count(OpName)) {
+        // If this is an predicate operand or optional def operand with an
+        // DefaultOps set filled in, we can ignore this.  When we codegen it,
+        // we will do so as always executed.
+        if (Op.Rec->isSubClassOf("PredicateOperand") ||
+            Op.Rec->isSubClassOf("OptionalDefOperand")) {
+          // Does it have a non-empty DefaultOps field?  If so, ignore this
+          // operand.
+          if (!getDefaultOperand(Op.Rec).DefaultOps.empty())
+            continue;
+        }
+        I->error("Operand $" + OpName +
+                 " does not appear in the instruction pattern");
+      }
+      TreePatternNode *InVal = InstInputsCheck[OpName];
+      InstInputsCheck.erase(OpName);   // It occurred, remove from map.
+      
+      if (InVal->isLeaf() &&
+          dynamic_cast<DefInit*>(InVal->getLeafValue())) {
+        Record *InRec = static_cast<DefInit*>(InVal->getLeafValue())->getDef();
+        if (Op.Rec != InRec && !InRec->isSubClassOf("ComplexPattern"))
+          I->error("Operand $" + OpName + "'s register class disagrees"
+                   " between the operand and pattern");
+      }
+      Operands.push_back(Op.Rec);
+      
+      // Construct the result for the dest-pattern operand list.
+      TreePatternNode *OpNode = InVal->clone();
+      
+      // No predicate is useful on the result.
+      OpNode->setPredicateFn("");
+      
+      // Promote the xform function to be an explicit node if set.
+      if (Record *Xform = OpNode->getTransformFn()) {
+        OpNode->setTransformFn(0);
+        std::vector<TreePatternNode*> Children;
+        Children.push_back(OpNode);
+        OpNode = new TreePatternNode(Xform, Children);
+      }
+      
+      ResultNodeOperands.push_back(OpNode);
+    }
+    
+    if (!InstInputsCheck.empty())
+      I->error("Input operand $" + InstInputsCheck.begin()->first +
+               " occurs in pattern but not in operands list!");
+
+    TreePatternNode *ResultPattern =
+      new TreePatternNode(I->getRecord(), ResultNodeOperands);
+    // Copy fully inferred output node type to instruction result pattern.
+    if (NumResults > 0)
+      ResultPattern->setTypes(Res0Node->getExtTypes());
+
+    // Create and insert the instruction.
+    DAGInstruction TheInst(I, Results, Operands, InstImpResults, InstImpInputs);
+    Instructions.insert(std::make_pair(I->getRecord(), TheInst));
+
+    // Use a temporary tree pattern to infer all types and make sure that the
+    // constructed result is correct.  This depends on the instruction already
+    // being inserted into the Instructions map.
+    TreePattern Temp(I->getRecord(), ResultPattern, false, *this);
+    Temp.InferAllTypes();
+
+    DAGInstruction &TheInsertedInst = Instructions.find(I->getRecord())->second;
+    TheInsertedInst.setResultPattern(Temp.getOnlyTree());
+    
+    DEBUG(I->dump());
+  }
+   
+  // If we can, convert the instructions to be patterns that are matched!
+  for (std::map<Record*, DAGInstruction>::iterator II = Instructions.begin(),
+       E = Instructions.end(); II != E; ++II) {
+    DAGInstruction &TheInst = II->second;
+    TreePattern *I = TheInst.getPattern();
+    if (I == 0) continue;  // No pattern.
+
+    if (I->getNumTrees() != 1) {
+      cerr << "CANNOT HANDLE: " << I->getRecord()->getName() << " yet!";
+      continue;
+    }
+    TreePatternNode *Pattern = I->getTree(0);
+    TreePatternNode *SrcPattern;
+    if (Pattern->getOperator()->getName() == "set") {
+      if (Pattern->getNumChildren() != 2)
+        continue;  // Not a set of a single value (not handled so far)
+
+      SrcPattern = Pattern->getChild(1)->clone();    
+    } else{
+      // Not a set (store or something?)
+      SrcPattern = Pattern;
+    }
+    
+    std::string Reason;
+    if (!SrcPattern->canPatternMatch(Reason, *this))
+      I->error("Instruction can never match: " + Reason);
+    
+    Record *Instr = II->first;
+    TreePatternNode *DstPattern = TheInst.getResultPattern();
+    PatternsToMatch.
+      push_back(PatternToMatch(Instr->getValueAsListInit("Predicates"),
+                               SrcPattern, DstPattern,
+                               Instr->getValueAsInt("AddedComplexity")));
+  }
+}
+
+void DAGISelEmitter::ParsePatterns() {
+  std::vector<Record*> Patterns = Records.getAllDerivedDefinitions("Pattern");
+
+  for (unsigned i = 0, e = Patterns.size(); i != e; ++i) {
+    DagInit *Tree = Patterns[i]->getValueAsDag("PatternToMatch");
+    TreePattern *Pattern = new TreePattern(Patterns[i], Tree, true, *this);
+
+    // Inline pattern fragments into it.
+    Pattern->InlinePatternFragments();
+    
+    ListInit *LI = Patterns[i]->getValueAsListInit("ResultInstrs");
+    if (LI->getSize() == 0) continue;  // no pattern.
+    
+    // Parse the instruction.
+    TreePattern *Result = new TreePattern(Patterns[i], LI, false, *this);
+    
+    // Inline pattern fragments into it.
+    Result->InlinePatternFragments();
+
+    if (Result->getNumTrees() != 1)
+      Result->error("Cannot handle instructions producing instructions "
+                    "with temporaries yet!");
+    
+    bool IterateInference;
+    bool InferredAllPatternTypes, InferredAllResultTypes;
+    do {
+      // Infer as many types as possible.  If we cannot infer all of them, we
+      // can never do anything with this pattern: report it to the user.
+      InferredAllPatternTypes = Pattern->InferAllTypes();
+      
+      // Infer as many types as possible.  If we cannot infer all of them, we
+      // can never do anything with this pattern: report it to the user.
+      InferredAllResultTypes = Result->InferAllTypes();
+
+      // Apply the type of the result to the source pattern.  This helps us
+      // resolve cases where the input type is known to be a pointer type (which
+      // is considered resolved), but the result knows it needs to be 32- or
+      // 64-bits.  Infer the other way for good measure.
+      IterateInference = Pattern->getOnlyTree()->
+        UpdateNodeType(Result->getOnlyTree()->getExtTypes(), *Result);
+      IterateInference |= Result->getOnlyTree()->
+        UpdateNodeType(Pattern->getOnlyTree()->getExtTypes(), *Result);
+    } while (IterateInference);
+
+    // Verify that we inferred enough types that we can do something with the
+    // pattern and result.  If these fire the user has to add type casts.
+    if (!InferredAllPatternTypes)
+      Pattern->error("Could not infer all types in pattern!");
+    if (!InferredAllResultTypes)
+      Result->error("Could not infer all types in pattern result!");
+    
+    // Validate that the input pattern is correct.
+    {
+      std::map<std::string, TreePatternNode*> InstInputs;
+      std::map<std::string, TreePatternNode*> InstResults;
+      std::vector<Record*> InstImpInputs;
+      std::vector<Record*> InstImpResults;
+      FindPatternInputsAndOutputs(Pattern, Pattern->getOnlyTree(),
+                                  InstInputs, InstResults,
+                                  InstImpInputs, InstImpResults);
+    }
+
+    // Promote the xform function to be an explicit node if set.
+    std::vector<TreePatternNode*> ResultNodeOperands;
+    TreePatternNode *DstPattern = Result->getOnlyTree();
+    for (unsigned ii = 0, ee = DstPattern->getNumChildren(); ii != ee; ++ii) {
+      TreePatternNode *OpNode = DstPattern->getChild(ii);
+      if (Record *Xform = OpNode->getTransformFn()) {
+        OpNode->setTransformFn(0);
+        std::vector<TreePatternNode*> Children;
+        Children.push_back(OpNode);
+        OpNode = new TreePatternNode(Xform, Children);
+      }
+      ResultNodeOperands.push_back(OpNode);
+    }
+    DstPattern = Result->getOnlyTree();
+    if (!DstPattern->isLeaf())
+      DstPattern = new TreePatternNode(DstPattern->getOperator(),
+                                       ResultNodeOperands);
+    DstPattern->setTypes(Result->getOnlyTree()->getExtTypes());
+    TreePattern Temp(Result->getRecord(), DstPattern, false, *this);
+    Temp.InferAllTypes();
+
+    std::string Reason;
+    if (!Pattern->getOnlyTree()->canPatternMatch(Reason, *this))
+      Pattern->error("Pattern can never match: " + Reason);
+    
+    PatternsToMatch.
+      push_back(PatternToMatch(Patterns[i]->getValueAsListInit("Predicates"),
+                               Pattern->getOnlyTree(),
+                               Temp.getOnlyTree(),
+                               Patterns[i]->getValueAsInt("AddedComplexity")));
+  }
+}
+
+/// CombineChildVariants - Given a bunch of permutations of each child of the
+/// 'operator' node, put them together in all possible ways.
+static void CombineChildVariants(TreePatternNode *Orig, 
+               const std::vector<std::vector<TreePatternNode*> > &ChildVariants,
+                                 std::vector<TreePatternNode*> &OutVariants,
+                                 DAGISelEmitter &ISE) {
+  // Make sure that each operand has at least one variant to choose from.
+  for (unsigned i = 0, e = ChildVariants.size(); i != e; ++i)
+    if (ChildVariants[i].empty())
+      return;
+        
+  // The end result is an all-pairs construction of the resultant pattern.
+  std::vector<unsigned> Idxs;
+  Idxs.resize(ChildVariants.size());
+  bool NotDone = true;
+  while (NotDone) {
+    // Create the variant and add it to the output list.
+    std::vector<TreePatternNode*> NewChildren;
+    for (unsigned i = 0, e = ChildVariants.size(); i != e; ++i)
+      NewChildren.push_back(ChildVariants[i][Idxs[i]]);
+    TreePatternNode *R = new TreePatternNode(Orig->getOperator(), NewChildren);
+    
+    // Copy over properties.
+    R->setName(Orig->getName());
+    R->setPredicateFn(Orig->getPredicateFn());
+    R->setTransformFn(Orig->getTransformFn());
+    R->setTypes(Orig->getExtTypes());
+    
+    // If this pattern cannot every match, do not include it as a variant.
+    std::string ErrString;
+    if (!R->canPatternMatch(ErrString, ISE)) {
+      delete R;
+    } else {
+      bool AlreadyExists = false;
+      
+      // Scan to see if this pattern has already been emitted.  We can get
+      // duplication due to things like commuting:
+      //   (and GPRC:$a, GPRC:$b) -> (and GPRC:$b, GPRC:$a)
+      // which are the same pattern.  Ignore the dups.
+      for (unsigned i = 0, e = OutVariants.size(); i != e; ++i)
+        if (R->isIsomorphicTo(OutVariants[i])) {
+          AlreadyExists = true;
+          break;
+        }
+      
+      if (AlreadyExists)
+        delete R;
+      else
+        OutVariants.push_back(R);
+    }
+    
+    // Increment indices to the next permutation.
+    NotDone = false;
+    // Look for something we can increment without causing a wrap-around.
+    for (unsigned IdxsIdx = 0; IdxsIdx != Idxs.size(); ++IdxsIdx) {
+      if (++Idxs[IdxsIdx] < ChildVariants[IdxsIdx].size()) {
+        NotDone = true;   // Found something to increment.
+        break;
+      }
+      Idxs[IdxsIdx] = 0;
+    }
+  }
+}
+
+/// CombineChildVariants - A helper function for binary operators.
+///
+static void CombineChildVariants(TreePatternNode *Orig, 
+                                 const std::vector<TreePatternNode*> &LHS,
+                                 const std::vector<TreePatternNode*> &RHS,
+                                 std::vector<TreePatternNode*> &OutVariants,
+                                 DAGISelEmitter &ISE) {
+  std::vector<std::vector<TreePatternNode*> > ChildVariants;
+  ChildVariants.push_back(LHS);
+  ChildVariants.push_back(RHS);
+  CombineChildVariants(Orig, ChildVariants, OutVariants, ISE);
+}  
+
+
+static void GatherChildrenOfAssociativeOpcode(TreePatternNode *N,
+                                     std::vector<TreePatternNode *> &Children) {
+  assert(N->getNumChildren()==2 &&"Associative but doesn't have 2 children!");
+  Record *Operator = N->getOperator();
+  
+  // Only permit raw nodes.
+  if (!N->getName().empty() || !N->getPredicateFn().empty() ||
+      N->getTransformFn()) {
+    Children.push_back(N);
+    return;
+  }
+
+  if (N->getChild(0)->isLeaf() || N->getChild(0)->getOperator() != Operator)
+    Children.push_back(N->getChild(0));
+  else
+    GatherChildrenOfAssociativeOpcode(N->getChild(0), Children);
+
+  if (N->getChild(1)->isLeaf() || N->getChild(1)->getOperator() != Operator)
+    Children.push_back(N->getChild(1));
+  else
+    GatherChildrenOfAssociativeOpcode(N->getChild(1), Children);
+}
+
+/// GenerateVariantsOf - Given a pattern N, generate all permutations we can of
+/// the (potentially recursive) pattern by using algebraic laws.
+///
+static void GenerateVariantsOf(TreePatternNode *N,
+                               std::vector<TreePatternNode*> &OutVariants,
+                               DAGISelEmitter &ISE) {
+  // We cannot permute leaves.
+  if (N->isLeaf()) {
+    OutVariants.push_back(N);
+    return;
+  }
+
+  // Look up interesting info about the node.
+  const SDNodeInfo &NodeInfo = ISE.getSDNodeInfo(N->getOperator());
+
+  // If this node is associative, reassociate.
+  if (NodeInfo.hasProperty(SDNPAssociative)) {
+    // Reassociate by pulling together all of the linked operators 
+    std::vector<TreePatternNode*> MaximalChildren;
+    GatherChildrenOfAssociativeOpcode(N, MaximalChildren);
+
+    // Only handle child sizes of 3.  Otherwise we'll end up trying too many
+    // permutations.
+    if (MaximalChildren.size() == 3) {
+      // Find the variants of all of our maximal children.
+      std::vector<TreePatternNode*> AVariants, BVariants, CVariants;
+      GenerateVariantsOf(MaximalChildren[0], AVariants, ISE);
+      GenerateVariantsOf(MaximalChildren[1], BVariants, ISE);
+      GenerateVariantsOf(MaximalChildren[2], CVariants, ISE);
+      
+      // There are only two ways we can permute the tree:
+      //   (A op B) op C    and    A op (B op C)
+      // Within these forms, we can also permute A/B/C.
+      
+      // Generate legal pair permutations of A/B/C.
+      std::vector<TreePatternNode*> ABVariants;
+      std::vector<TreePatternNode*> BAVariants;
+      std::vector<TreePatternNode*> ACVariants;
+      std::vector<TreePatternNode*> CAVariants;
+      std::vector<TreePatternNode*> BCVariants;
+      std::vector<TreePatternNode*> CBVariants;
+      CombineChildVariants(N, AVariants, BVariants, ABVariants, ISE);
+      CombineChildVariants(N, BVariants, AVariants, BAVariants, ISE);
+      CombineChildVariants(N, AVariants, CVariants, ACVariants, ISE);
+      CombineChildVariants(N, CVariants, AVariants, CAVariants, ISE);
+      CombineChildVariants(N, BVariants, CVariants, BCVariants, ISE);
+      CombineChildVariants(N, CVariants, BVariants, CBVariants, ISE);
+
+      // Combine those into the result: (x op x) op x
+      CombineChildVariants(N, ABVariants, CVariants, OutVariants, ISE);
+      CombineChildVariants(N, BAVariants, CVariants, OutVariants, ISE);
+      CombineChildVariants(N, ACVariants, BVariants, OutVariants, ISE);
+      CombineChildVariants(N, CAVariants, BVariants, OutVariants, ISE);
+      CombineChildVariants(N, BCVariants, AVariants, OutVariants, ISE);
+      CombineChildVariants(N, CBVariants, AVariants, OutVariants, ISE);
+
+      // Combine those into the result: x op (x op x)
+      CombineChildVariants(N, CVariants, ABVariants, OutVariants, ISE);
+      CombineChildVariants(N, CVariants, BAVariants, OutVariants, ISE);
+      CombineChildVariants(N, BVariants, ACVariants, OutVariants, ISE);
+      CombineChildVariants(N, BVariants, CAVariants, OutVariants, ISE);
+      CombineChildVariants(N, AVariants, BCVariants, OutVariants, ISE);
+      CombineChildVariants(N, AVariants, CBVariants, OutVariants, ISE);
+      return;
+    }
+  }
+  
+  // Compute permutations of all children.
+  std::vector<std::vector<TreePatternNode*> > ChildVariants;
+  ChildVariants.resize(N->getNumChildren());
+  for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
+    GenerateVariantsOf(N->getChild(i), ChildVariants[i], ISE);
+
+  // Build all permutations based on how the children were formed.
+  CombineChildVariants(N, ChildVariants, OutVariants, ISE);
+
+  // If this node is commutative, consider the commuted order.
+  if (NodeInfo.hasProperty(SDNPCommutative)) {
+    assert(N->getNumChildren()==2 &&"Commutative but doesn't have 2 children!");
+    // Don't count children which are actually register references.
+    unsigned NC = 0;
+    for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i) {
+      TreePatternNode *Child = N->getChild(i);
+      if (Child->isLeaf())
+        if (DefInit *DI = dynamic_cast<DefInit*>(Child->getLeafValue())) {
+          Record *RR = DI->getDef();
+          if (RR->isSubClassOf("Register"))
+            continue;
+        }
+      NC++;
+    }
+    // Consider the commuted order.
+    if (NC == 2)
+      CombineChildVariants(N, ChildVariants[1], ChildVariants[0],
+                           OutVariants, ISE);
+  }
+}
+
+
+// GenerateVariants - Generate variants.  For example, commutative patterns can
+// match multiple ways.  Add them to PatternsToMatch as well.
+void DAGISelEmitter::GenerateVariants() {
+  
+  DOUT << "Generating instruction variants.\n";
+  
+  // Loop over all of the patterns we've collected, checking to see if we can
+  // generate variants of the instruction, through the exploitation of
+  // identities.  This permits the target to provide agressive matching without
+  // the .td file having to contain tons of variants of instructions.
+  //
+  // Note that this loop adds new patterns to the PatternsToMatch list, but we
+  // intentionally do not reconsider these.  Any variants of added patterns have
+  // already been added.
+  //
+  for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i) {
+    std::vector<TreePatternNode*> Variants;
+    GenerateVariantsOf(PatternsToMatch[i].getSrcPattern(), Variants, *this);
+
+    assert(!Variants.empty() && "Must create at least original variant!");
+    Variants.erase(Variants.begin());  // Remove the original pattern.
+
+    if (Variants.empty())  // No variants for this pattern.
+      continue;
+
+    DOUT << "FOUND VARIANTS OF: ";
+    DEBUG(PatternsToMatch[i].getSrcPattern()->dump());
+    DOUT << "\n";
+
+    for (unsigned v = 0, e = Variants.size(); v != e; ++v) {
+      TreePatternNode *Variant = Variants[v];
+
+      DOUT << "  VAR#" << v <<  ": ";
+      DEBUG(Variant->dump());
+      DOUT << "\n";
+      
+      // Scan to see if an instruction or explicit pattern already matches this.
+      bool AlreadyExists = false;
+      for (unsigned p = 0, e = PatternsToMatch.size(); p != e; ++p) {
+        // Check to see if this variant already exists.
+        if (Variant->isIsomorphicTo(PatternsToMatch[p].getSrcPattern())) {
+          DOUT << "  *** ALREADY EXISTS, ignoring variant.\n";
+          AlreadyExists = true;
+          break;
+        }
+      }
+      // If we already have it, ignore the variant.
+      if (AlreadyExists) continue;
+
+      // Otherwise, add it to the list of patterns we have.
+      PatternsToMatch.
+        push_back(PatternToMatch(PatternsToMatch[i].getPredicates(),
+                                 Variant, PatternsToMatch[i].getDstPattern(),
+                                 PatternsToMatch[i].getAddedComplexity()));
+    }
+
+    DOUT << "\n";
+  }
+}
+
+// NodeIsComplexPattern - return true if N is a leaf node and a subclass of
+// ComplexPattern.
+static bool NodeIsComplexPattern(TreePatternNode *N)
+{
+  return (N->isLeaf() &&
+          dynamic_cast<DefInit*>(N->getLeafValue()) &&
+          static_cast<DefInit*>(N->getLeafValue())->getDef()->
+          isSubClassOf("ComplexPattern"));
+}
+
+// NodeGetComplexPattern - return the pointer to the ComplexPattern if N
+// is a leaf node and a subclass of ComplexPattern, else it returns NULL.
+static const ComplexPattern *NodeGetComplexPattern(TreePatternNode *N,
+                                                   DAGISelEmitter &ISE)
+{
+  if (N->isLeaf() &&
+      dynamic_cast<DefInit*>(N->getLeafValue()) &&
+      static_cast<DefInit*>(N->getLeafValue())->getDef()->
+      isSubClassOf("ComplexPattern")) {
+    return &ISE.getComplexPattern(static_cast<DefInit*>(N->getLeafValue())
+                                  ->getDef());
+  }
+  return NULL;
+}
+
+/// getPatternSize - Return the 'size' of this pattern.  We want to match large
+/// patterns before small ones.  This is used to determine the size of a
+/// pattern.
+static unsigned getPatternSize(TreePatternNode *P, DAGISelEmitter &ISE) {
+  assert((isExtIntegerInVTs(P->getExtTypes()) || 
+          isExtFloatingPointInVTs(P->getExtTypes()) ||
+          P->getExtTypeNum(0) == MVT::isVoid ||
+          P->getExtTypeNum(0) == MVT::Flag ||
+          P->getExtTypeNum(0) == MVT::iPTR) && 
+         "Not a valid pattern node to size!");
+  unsigned Size = 3;  // The node itself.
+  // If the root node is a ConstantSDNode, increases its size.
+  // e.g. (set R32:$dst, 0).
+  if (P->isLeaf() && dynamic_cast<IntInit*>(P->getLeafValue()))
+    Size += 2;
+
+  // FIXME: This is a hack to statically increase the priority of patterns
+  // which maps a sub-dag to a complex pattern. e.g. favors LEA over ADD.
+  // Later we can allow complexity / cost for each pattern to be (optionally)
+  // specified. To get best possible pattern match we'll need to dynamically
+  // calculate the complexity of all patterns a dag can potentially map to.
+  const ComplexPattern *AM = NodeGetComplexPattern(P, ISE);
+  if (AM)
+    Size += AM->getNumOperands() * 3;
+
+  // If this node has some predicate function that must match, it adds to the
+  // complexity of this node.
+  if (!P->getPredicateFn().empty())
+    ++Size;
+  
+  // Count children in the count if they are also nodes.
+  for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i) {
+    TreePatternNode *Child = P->getChild(i);
+    if (!Child->isLeaf() && Child->getExtTypeNum(0) != MVT::Other)
+      Size += getPatternSize(Child, ISE);
+    else if (Child->isLeaf()) {
+      if (dynamic_cast<IntInit*>(Child->getLeafValue())) 
+        Size += 5;  // Matches a ConstantSDNode (+3) and a specific value (+2).
+      else if (NodeIsComplexPattern(Child))
+        Size += getPatternSize(Child, ISE);
+      else if (!Child->getPredicateFn().empty())
+        ++Size;
+    }
+  }
+  
+  return Size;
+}
+
+/// getResultPatternCost - Compute the number of instructions for this pattern.
+/// This is a temporary hack.  We should really include the instruction
+/// latencies in this calculation.
+static unsigned getResultPatternCost(TreePatternNode *P, DAGISelEmitter &ISE) {
+  if (P->isLeaf()) return 0;
+  
+  unsigned Cost = 0;
+  Record *Op = P->getOperator();
+  if (Op->isSubClassOf("Instruction")) {
+    Cost++;
+    CodeGenInstruction &II = ISE.getTargetInfo().getInstruction(Op->getName());
+    if (II.usesCustomDAGSchedInserter)
+      Cost += 10;
+  }
+  for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i)
+    Cost += getResultPatternCost(P->getChild(i), ISE);
+  return Cost;
+}
+
+/// getResultPatternCodeSize - Compute the code size of instructions for this
+/// pattern.
+static unsigned getResultPatternSize(TreePatternNode *P, DAGISelEmitter &ISE) {
+  if (P->isLeaf()) return 0;
+
+  unsigned Cost = 0;
+  Record *Op = P->getOperator();
+  if (Op->isSubClassOf("Instruction")) {
+    Cost += Op->getValueAsInt("CodeSize");
+  }
+  for (unsigned i = 0, e = P->getNumChildren(); i != e; ++i)
+    Cost += getResultPatternSize(P->getChild(i), ISE);
+  return Cost;
+}
+
+// PatternSortingPredicate - return true if we prefer to match LHS before RHS.
+// In particular, we want to match maximal patterns first and lowest cost within
+// a particular complexity first.
+struct PatternSortingPredicate {
+  PatternSortingPredicate(DAGISelEmitter &ise) : ISE(ise) {};
+  DAGISelEmitter &ISE;
+
+  bool operator()(PatternToMatch *LHS,
+                  PatternToMatch *RHS) {
+    unsigned LHSSize = getPatternSize(LHS->getSrcPattern(), ISE);
+    unsigned RHSSize = getPatternSize(RHS->getSrcPattern(), ISE);
+    LHSSize += LHS->getAddedComplexity();
+    RHSSize += RHS->getAddedComplexity();
+    if (LHSSize > RHSSize) return true;   // LHS -> bigger -> less cost
+    if (LHSSize < RHSSize) return false;
+    
+    // If the patterns have equal complexity, compare generated instruction cost
+    unsigned LHSCost = getResultPatternCost(LHS->getDstPattern(), ISE);
+    unsigned RHSCost = getResultPatternCost(RHS->getDstPattern(), ISE);
+    if (LHSCost < RHSCost) return true;
+    if (LHSCost > RHSCost) return false;
+
+    return getResultPatternSize(LHS->getDstPattern(), ISE) <
+      getResultPatternSize(RHS->getDstPattern(), ISE);
+  }
+};
+
+/// getRegisterValueType - Look up and return the first ValueType of specified 
+/// RegisterClass record
+static MVT::ValueType getRegisterValueType(Record *R, const CodeGenTarget &T) {
+  if (const CodeGenRegisterClass *RC = T.getRegisterClassForRegister(R))
+    return RC->getValueTypeNum(0);
+  return MVT::Other;
+}
+
+
+/// RemoveAllTypes - A quick recursive walk over a pattern which removes all
+/// type information from it.
+static void RemoveAllTypes(TreePatternNode *N) {
+  N->removeTypes();
+  if (!N->isLeaf())
+    for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
+      RemoveAllTypes(N->getChild(i));
+}
+
+Record *DAGISelEmitter::getSDNodeNamed(const std::string &Name) const {
+  Record *N = Records.getDef(Name);
+  if (!N || !N->isSubClassOf("SDNode")) {
+    cerr << "Error getting SDNode '" << Name << "'!\n";
+    exit(1);
+  }
+  return N;
+}
+
+/// NodeHasProperty - return true if TreePatternNode has the specified
+/// property.
+static bool NodeHasProperty(TreePatternNode *N, SDNP Property,
+                            DAGISelEmitter &ISE)
+{
+  if (N->isLeaf()) {
+    const ComplexPattern *CP = NodeGetComplexPattern(N, ISE);
+    if (CP)
+      return CP->hasProperty(Property);
+    return false;
+  }
+  Record *Operator = N->getOperator();
+  if (!Operator->isSubClassOf("SDNode")) return false;
+
+  const SDNodeInfo &NodeInfo = ISE.getSDNodeInfo(Operator);
+  return NodeInfo.hasProperty(Property);
+}
+
+static bool PatternHasProperty(TreePatternNode *N, SDNP Property,
+                               DAGISelEmitter &ISE)
+{
+  if (NodeHasProperty(N, Property, ISE))
+    return true;
+
+  for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i) {
+    TreePatternNode *Child = N->getChild(i);
+    if (PatternHasProperty(Child, Property, ISE))
+      return true;
+  }
+
+  return false;
+}
+
+class PatternCodeEmitter {
+private:
+  DAGISelEmitter &ISE;
+
+  // Predicates.
+  ListInit *Predicates;
+  // Pattern cost.
+  unsigned Cost;
+  // Instruction selector pattern.
+  TreePatternNode *Pattern;
+  // Matched instruction.
+  TreePatternNode *Instruction;
+  
+  // Node to name mapping
+  std::map<std::string, std::string> VariableMap;
+  // Node to operator mapping
+  std::map<std::string, Record*> OperatorMap;
+  // Names of all the folded nodes which produce chains.
+  std::vector<std::pair<std::string, unsigned> > FoldedChains;
+  // Original input chain(s).
+  std::vector<std::pair<std::string, std::string> > OrigChains;
+  std::set<std::string> Duplicates;
+
+  /// GeneratedCode - This is the buffer that we emit code to.  The first int
+  /// indicates whether this is an exit predicate (something that should be
+  /// tested, and if true, the match fails) [when 1], or normal code to emit
+  /// [when 0], or initialization code to emit [when 2].
+  std::vector<std::pair<unsigned, std::string> > &GeneratedCode;
+  /// GeneratedDecl - This is the set of all SDOperand declarations needed for
+  /// the set of patterns for each top-level opcode.
+  std::set<std::string> &GeneratedDecl;
+  /// TargetOpcodes - The target specific opcodes used by the resulting
+  /// instructions.
+  std::vector<std::string> &TargetOpcodes;
+  std::vector<std::string> &TargetVTs;
+
+  std::string ChainName;
+  unsigned TmpNo;
+  unsigned OpcNo;
+  unsigned VTNo;
+  
+  void emitCheck(const std::string &S) {
+    if (!S.empty())
+      GeneratedCode.push_back(std::make_pair(1, S));
+  }
+  void emitCode(const std::string &S) {
+    if (!S.empty())
+      GeneratedCode.push_back(std::make_pair(0, S));
+  }
+  void emitInit(const std::string &S) {
+    if (!S.empty())
+      GeneratedCode.push_back(std::make_pair(2, S));
+  }
+  void emitDecl(const std::string &S) {
+    assert(!S.empty() && "Invalid declaration");
+    GeneratedDecl.insert(S);
+  }
+  void emitOpcode(const std::string &Opc) {
+    TargetOpcodes.push_back(Opc);
+    OpcNo++;
+  }
+  void emitVT(const std::string &VT) {
+    TargetVTs.push_back(VT);
+    VTNo++;
+  }
+public:
+  PatternCodeEmitter(DAGISelEmitter &ise, ListInit *preds,
+                     TreePatternNode *pattern, TreePatternNode *instr,
+                     std::vector<std::pair<unsigned, std::string> > &gc,
+                     std::set<std::string> &gd,
+                     std::vector<std::string> &to,
+                     std::vector<std::string> &tv)
+  : ISE(ise), Predicates(preds), Pattern(pattern), Instruction(instr),
+    GeneratedCode(gc), GeneratedDecl(gd),
+    TargetOpcodes(to), TargetVTs(tv),
+    TmpNo(0), OpcNo(0), VTNo(0) {}
+
+  /// EmitMatchCode - Emit a matcher for N, going to the label for PatternNo
+  /// if the match fails. At this point, we already know that the opcode for N
+  /// matches, and the SDNode for the result has the RootName specified name.
+  void EmitMatchCode(TreePatternNode *N, TreePatternNode *P,
+                     const std::string &RootName, const std::string &ChainSuffix,
+                     bool &FoundChain) {
+    bool isRoot = (P == NULL);
+    // Emit instruction predicates. Each predicate is just a string for now.
+    if (isRoot) {
+      std::string PredicateCheck;
+      for (unsigned i = 0, e = Predicates->getSize(); i != e; ++i) {
+        if (DefInit *Pred = dynamic_cast<DefInit*>(Predicates->getElement(i))) {
+          Record *Def = Pred->getDef();
+          if (!Def->isSubClassOf("Predicate")) {
+#ifndef NDEBUG
+            Def->dump();
+#endif
+            assert(0 && "Unknown predicate type!");
+          }
+          if (!PredicateCheck.empty())
+            PredicateCheck += " && ";
+          PredicateCheck += "(" + Def->getValueAsString("CondString") + ")";
+        }
+      }
+      
+      emitCheck(PredicateCheck);
+    }
+
+    if (N->isLeaf()) {
+      if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) {
+        emitCheck("cast<ConstantSDNode>(" + RootName +
+                  ")->getSignExtended() == " + itostr(II->getValue()));
+        return;
+      } else if (!NodeIsComplexPattern(N)) {
+        assert(0 && "Cannot match this as a leaf value!");
+        abort();
+      }
+    }
+  
+    // If this node has a name associated with it, capture it in VariableMap. If
+    // we already saw this in the pattern, emit code to verify dagness.
+    if (!N->getName().empty()) {
+      std::string &VarMapEntry = VariableMap[N->getName()];
+      if (VarMapEntry.empty()) {
+        VarMapEntry = RootName;
+      } else {
+        // If we get here, this is a second reference to a specific name.  Since
+        // we already have checked that the first reference is valid, we don't
+        // have to recursively match it, just check that it's the same as the
+        // previously named thing.
+        emitCheck(VarMapEntry + " == " + RootName);
+        return;
+      }
+
+      if (!N->isLeaf())
+        OperatorMap[N->getName()] = N->getOperator();
+    }
+
+
+    // Emit code to load the child nodes and match their contents recursively.
+    unsigned OpNo = 0;
+    bool NodeHasChain = NodeHasProperty   (N, SDNPHasChain, ISE);
+    bool HasChain     = PatternHasProperty(N, SDNPHasChain, ISE);
+    bool EmittedUseCheck = false;
+    if (HasChain) {
+      if (NodeHasChain)
+        OpNo = 1;
+      if (!isRoot) {
+        // Multiple uses of actual result?
+        emitCheck(RootName + ".hasOneUse()");
+        EmittedUseCheck = true;
+        if (NodeHasChain) {
+          // If the immediate use can somehow reach this node through another
+          // path, then can't fold it either or it will create a cycle.
+          // e.g. In the following diagram, XX can reach ld through YY. If
+          // ld is folded into XX, then YY is both a predecessor and a successor
+          // of XX.
+          //
+          //         [ld]
+          //         ^  ^
+          //         |  |
+          //        /   \---
+          //      /        [YY]
+          //      |         ^
+          //     [XX]-------|
+          bool NeedCheck = false;
+          if (P != Pattern)
+            NeedCheck = true;
+          else {
+            const SDNodeInfo &PInfo = ISE.getSDNodeInfo(P->getOperator());
+            NeedCheck =
+              P->getOperator() == ISE.get_intrinsic_void_sdnode() ||
+              P->getOperator() == ISE.get_intrinsic_w_chain_sdnode() ||
+              P->getOperator() == ISE.get_intrinsic_wo_chain_sdnode() ||
+              PInfo.getNumOperands() > 1 ||
+              PInfo.hasProperty(SDNPHasChain) ||
+              PInfo.hasProperty(SDNPInFlag) ||
+              PInfo.hasProperty(SDNPOptInFlag);
+          }
+
+          if (NeedCheck) {
+            std::string ParentName(RootName.begin(), RootName.end()-1);
+            emitCheck("CanBeFoldedBy(" + RootName + ".Val, " + ParentName +
+                      ".Val, N.Val)");
+          }
+        }
+      }
+
+      if (NodeHasChain) {
+        if (FoundChain) {
+          emitCheck("(" + ChainName + ".Val == " + RootName + ".Val || "
+                    "IsChainCompatible(" + ChainName + ".Val, " +
+                    RootName + ".Val))");
+          OrigChains.push_back(std::make_pair(ChainName, RootName));
+        } else
+          FoundChain = true;
+        ChainName = "Chain" + ChainSuffix;
+        emitInit("SDOperand " + ChainName + " = " + RootName +
+                 ".getOperand(0);");
+      }
+    }
+
+    // Don't fold any node which reads or writes a flag and has multiple uses.
+    // FIXME: We really need to separate the concepts of flag and "glue". Those
+    // real flag results, e.g. X86CMP output, can have multiple uses.
+    // FIXME: If the optional incoming flag does not exist. Then it is ok to
+    // fold it.
+    if (!isRoot &&
+        (PatternHasProperty(N, SDNPInFlag, ISE) ||
+         PatternHasProperty(N, SDNPOptInFlag, ISE) ||
+         PatternHasProperty(N, SDNPOutFlag, ISE))) {
+      if (!EmittedUseCheck) {
+        // Multiple uses of actual result?
+        emitCheck(RootName + ".hasOneUse()");
+      }
+    }
+
+    // If there is a node predicate for this, emit the call.
+    if (!N->getPredicateFn().empty())
+      emitCheck(N->getPredicateFn() + "(" + RootName + ".Val)");
+
+    
+    // If this is an 'and R, 1234' where the operation is AND/OR and the RHS is
+    // a constant without a predicate fn that has more that one bit set, handle
+    // this as a special case.  This is usually for targets that have special
+    // handling of certain large constants (e.g. alpha with it's 8/16/32-bit
+    // handling stuff).  Using these instructions is often far more efficient
+    // than materializing the constant.  Unfortunately, both the instcombiner
+    // and the dag combiner can often infer that bits are dead, and thus drop
+    // them from the mask in the dag.  For example, it might turn 'AND X, 255'
+    // into 'AND X, 254' if it knows the low bit is set.  Emit code that checks
+    // to handle this.
+    if (!N->isLeaf() && 
+        (N->getOperator()->getName() == "and" || 
+         N->getOperator()->getName() == "or") &&
+        N->getChild(1)->isLeaf() &&
+        N->getChild(1)->getPredicateFn().empty()) {
+      if (IntInit *II = dynamic_cast<IntInit*>(N->getChild(1)->getLeafValue())) {
+        if (!isPowerOf2_32(II->getValue())) {  // Don't bother with single bits.
+          emitInit("SDOperand " + RootName + "0" + " = " +
+                   RootName + ".getOperand(" + utostr(0) + ");");
+          emitInit("SDOperand " + RootName + "1" + " = " +
+                   RootName + ".getOperand(" + utostr(1) + ");");
+
+          emitCheck("isa<ConstantSDNode>(" + RootName + "1)");
+          const char *MaskPredicate = N->getOperator()->getName() == "or"
+            ? "CheckOrMask(" : "CheckAndMask(";
+          emitCheck(MaskPredicate + RootName + "0, cast<ConstantSDNode>(" +
+                    RootName + "1), " + itostr(II->getValue()) + ")");
+          
+          EmitChildMatchCode(N->getChild(0), N, RootName + utostr(0),
+                             ChainSuffix + utostr(0), FoundChain);
+          return;
+        }
+      }
+    }
+    
+    for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i, ++OpNo) {
+      emitInit("SDOperand " + RootName + utostr(OpNo) + " = " +
+               RootName + ".getOperand(" +utostr(OpNo) + ");");
+
+      EmitChildMatchCode(N->getChild(i), N, RootName + utostr(OpNo),
+                         ChainSuffix + utostr(OpNo), FoundChain);
+    }
+
+    // Handle cases when root is a complex pattern.
+    const ComplexPattern *CP;
+    if (isRoot && N->isLeaf() && (CP = NodeGetComplexPattern(N, ISE))) {
+      std::string Fn = CP->getSelectFunc();
+      unsigned NumOps = CP->getNumOperands();
+      for (unsigned i = 0; i < NumOps; ++i) {
+        emitDecl("CPTmp" + utostr(i));
+        emitCode("SDOperand CPTmp" + utostr(i) + ";");
+      }
+      if (CP->hasProperty(SDNPHasChain)) {
+        emitDecl("CPInChain");
+        emitDecl("Chain" + ChainSuffix);
+        emitCode("SDOperand CPInChain;");
+        emitCode("SDOperand Chain" + ChainSuffix + ";");
+      }
+
+      std::string Code = Fn + "(" + RootName + ", " + RootName;
+      for (unsigned i = 0; i < NumOps; i++)
+        Code += ", CPTmp" + utostr(i);
+      if (CP->hasProperty(SDNPHasChain)) {
+        ChainName = "Chain" + ChainSuffix;
+        Code += ", CPInChain, Chain" + ChainSuffix;
+      }
+      emitCheck(Code + ")");
+    }
+  }
+
+  void EmitChildMatchCode(TreePatternNode *Child, TreePatternNode *Parent,
+                          const std::string &RootName,
+                          const std::string &ChainSuffix, bool &FoundChain) {
+    if (!Child->isLeaf()) {
+      // If it's not a leaf, recursively match.
+      const SDNodeInfo &CInfo = ISE.getSDNodeInfo(Child->getOperator());
+      emitCheck(RootName + ".getOpcode() == " +
+                CInfo.getEnumName());
+      EmitMatchCode(Child, Parent, RootName, ChainSuffix, FoundChain);
+      if (NodeHasProperty(Child, SDNPHasChain, ISE))
+        FoldedChains.push_back(std::make_pair(RootName, CInfo.getNumResults()));
+    } else {
+      // If this child has a name associated with it, capture it in VarMap. If
+      // we already saw this in the pattern, emit code to verify dagness.
+      if (!Child->getName().empty()) {
+        std::string &VarMapEntry = VariableMap[Child->getName()];
+        if (VarMapEntry.empty()) {
+          VarMapEntry = RootName;
+        } else {
+          // If we get here, this is a second reference to a specific name.
+          // Since we already have checked that the first reference is valid,
+          // we don't have to recursively match it, just check that it's the
+          // same as the previously named thing.
+          emitCheck(VarMapEntry + " == " + RootName);
+          Duplicates.insert(RootName);
+          return;
+        }
+      }
+      
+      // Handle leaves of various types.
+      if (DefInit *DI = dynamic_cast<DefInit*>(Child->getLeafValue())) {
+        Record *LeafRec = DI->getDef();
+        if (LeafRec->isSubClassOf("RegisterClass") || 
+            LeafRec->getName() == "ptr_rc") {
+          // Handle register references.  Nothing to do here.
+        } else if (LeafRec->isSubClassOf("Register")) {
+          // Handle register references.
+        } else if (LeafRec->isSubClassOf("ComplexPattern")) {
+          // Handle complex pattern.
+          const ComplexPattern *CP = NodeGetComplexPattern(Child, ISE);
+          std::string Fn = CP->getSelectFunc();
+          unsigned NumOps = CP->getNumOperands();
+          for (unsigned i = 0; i < NumOps; ++i) {
+            emitDecl("CPTmp" + utostr(i));
+            emitCode("SDOperand CPTmp" + utostr(i) + ";");
+          }
+          if (CP->hasProperty(SDNPHasChain)) {
+            const SDNodeInfo &PInfo = ISE.getSDNodeInfo(Parent->getOperator());
+            FoldedChains.push_back(std::make_pair("CPInChain",
+                                                  PInfo.getNumResults()));
+            ChainName = "Chain" + ChainSuffix;
+            emitDecl("CPInChain");
+            emitDecl(ChainName);
+            emitCode("SDOperand CPInChain;");
+            emitCode("SDOperand " + ChainName + ";");
+          }
+          
+          std::string Code = Fn + "(N, ";
+          if (CP->hasProperty(SDNPHasChain)) {
+            std::string ParentName(RootName.begin(), RootName.end()-1);
+            Code += ParentName + ", ";
+          }
+          Code += RootName;
+          for (unsigned i = 0; i < NumOps; i++)
+            Code += ", CPTmp" + utostr(i);
+          if (CP->hasProperty(SDNPHasChain))
+            Code += ", CPInChain, Chain" + ChainSuffix;
+          emitCheck(Code + ")");
+        } else if (LeafRec->getName() == "srcvalue") {
+          // Place holder for SRCVALUE nodes. Nothing to do here.
+        } else if (LeafRec->isSubClassOf("ValueType")) {
+          // Make sure this is the specified value type.
+          emitCheck("cast<VTSDNode>(" + RootName +
+                    ")->getVT() == MVT::" + LeafRec->getName());
+        } else if (LeafRec->isSubClassOf("CondCode")) {
+          // Make sure this is the specified cond code.
+          emitCheck("cast<CondCodeSDNode>(" + RootName +
+                    ")->get() == ISD::" + LeafRec->getName());
+        } else {
+#ifndef NDEBUG
+          Child->dump();
+          cerr << " ";
+#endif
+          assert(0 && "Unknown leaf type!");
+        }
+        
+        // If there is a node predicate for this, emit the call.
+        if (!Child->getPredicateFn().empty())
+          emitCheck(Child->getPredicateFn() + "(" + RootName +
+                    ".Val)");
+      } else if (IntInit *II =
+                 dynamic_cast<IntInit*>(Child->getLeafValue())) {
+        emitCheck("isa<ConstantSDNode>(" + RootName + ")");
+        unsigned CTmp = TmpNo++;
+        emitCode("int64_t CN"+utostr(CTmp)+" = cast<ConstantSDNode>("+
+                 RootName + ")->getSignExtended();");
+        
+        emitCheck("CN" + utostr(CTmp) + " == " +itostr(II->getValue()));
+      } else {
+#ifndef NDEBUG
+        Child->dump();
+#endif
+        assert(0 && "Unknown leaf type!");
+      }
+    }
+  }
+
+  /// EmitResultCode - Emit the action for a pattern.  Now that it has matched
+  /// we actually have to build a DAG!
+  std::vector<std::string>
+  EmitResultCode(TreePatternNode *N, bool RetSelected,
+                 bool InFlagDecled, bool ResNodeDecled,
+                 bool LikeLeaf = false, bool isRoot = false) {
+    // List of arguments of getTargetNode() or SelectNodeTo().
+    std::vector<std::string> NodeOps;
+    // This is something selected from the pattern we matched.
+    if (!N->getName().empty()) {
+      std::string &Val = VariableMap[N->getName()];
+      assert(!Val.empty() &&
+             "Variable referenced but not defined and not caught earlier!");
+      if (Val[0] == 'T' && Val[1] == 'm' && Val[2] == 'p') {
+        // Already selected this operand, just return the tmpval.
+        NodeOps.push_back(Val);
+        return NodeOps;
+      }
+
+      const ComplexPattern *CP;
+      unsigned ResNo = TmpNo++;
+      if (!N->isLeaf() && N->getOperator()->getName() == "imm") {
+        assert(N->getExtTypes().size() == 1 && "Multiple types not handled!");
+        std::string CastType;
+        switch (N->getTypeNum(0)) {
+        default:
+          cerr << "Cannot handle " << getEnumName(N->getTypeNum(0))
+               << " type as an immediate constant. Aborting\n";
+          abort();
+        case MVT::i1:  CastType = "bool"; break;
+        case MVT::i8:  CastType = "unsigned char"; break;
+        case MVT::i16: CastType = "unsigned short"; break;
+        case MVT::i32: CastType = "unsigned"; break;
+        case MVT::i64: CastType = "uint64_t"; break;
+        }
+        emitCode("SDOperand Tmp" + utostr(ResNo) + 
+                 " = CurDAG->getTargetConstant(((" + CastType +
+                 ") cast<ConstantSDNode>(" + Val + ")->getValue()), " +
+                 getEnumName(N->getTypeNum(0)) + ");");
+        NodeOps.push_back("Tmp" + utostr(ResNo));
+        // Add Tmp<ResNo> to VariableMap, so that we don't multiply select this
+        // value if used multiple times by this pattern result.
+        Val = "Tmp"+utostr(ResNo);
+      } else if (!N->isLeaf() && N->getOperator()->getName() == "texternalsym"){
+        Record *Op = OperatorMap[N->getName()];
+        // Transform ExternalSymbol to TargetExternalSymbol
+        if (Op && Op->getName() == "externalsym") {
+          emitCode("SDOperand Tmp" + utostr(ResNo) + " = CurDAG->getTarget"
+                   "ExternalSymbol(cast<ExternalSymbolSDNode>(" +
+                   Val + ")->getSymbol(), " +
+                   getEnumName(N->getTypeNum(0)) + ");");
+          NodeOps.push_back("Tmp" + utostr(ResNo));
+          // Add Tmp<ResNo> to VariableMap, so that we don't multiply select
+          // this value if used multiple times by this pattern result.
+          Val = "Tmp"+utostr(ResNo);
+        } else {
+          NodeOps.push_back(Val);
+        }
+      } else if (!N->isLeaf() && (N->getOperator()->getName() == "tglobaladdr"
+                 || N->getOperator()->getName() == "tglobaltlsaddr")) {
+        Record *Op = OperatorMap[N->getName()];
+        // Transform GlobalAddress to TargetGlobalAddress
+        if (Op && (Op->getName() == "globaladdr" ||
+                   Op->getName() == "globaltlsaddr")) {
+          emitCode("SDOperand Tmp" + utostr(ResNo) + " = CurDAG->getTarget"
+                   "GlobalAddress(cast<GlobalAddressSDNode>(" + Val +
+                   ")->getGlobal(), " + getEnumName(N->getTypeNum(0)) +
+                   ");");
+          NodeOps.push_back("Tmp" + utostr(ResNo));
+          // Add Tmp<ResNo> to VariableMap, so that we don't multiply select
+          // this value if used multiple times by this pattern result.
+          Val = "Tmp"+utostr(ResNo);
+        } else {
+          NodeOps.push_back(Val);
+        }
+      } else if (!N->isLeaf() && N->getOperator()->getName() == "texternalsym"){
+        NodeOps.push_back(Val);
+        // Add Tmp<ResNo> to VariableMap, so that we don't multiply select this
+        // value if used multiple times by this pattern result.
+        Val = "Tmp"+utostr(ResNo);
+      } else if (!N->isLeaf() && N->getOperator()->getName() == "tconstpool") {
+        NodeOps.push_back(Val);
+        // Add Tmp<ResNo> to VariableMap, so that we don't multiply select this
+        // value if used multiple times by this pattern result.
+        Val = "Tmp"+utostr(ResNo);
+      } else if (N->isLeaf() && (CP = NodeGetComplexPattern(N, ISE))) {
+        for (unsigned i = 0; i < CP->getNumOperands(); ++i) {
+          emitCode("AddToISelQueue(CPTmp" + utostr(i) + ");");
+          NodeOps.push_back("CPTmp" + utostr(i));
+        }
+      } else {
+        // This node, probably wrapped in a SDNodeXForm, behaves like a leaf
+        // node even if it isn't one. Don't select it.
+        if (!LikeLeaf) {
+          emitCode("AddToISelQueue(" + Val + ");");
+          if (isRoot && N->isLeaf()) {
+            emitCode("ReplaceUses(N, " + Val + ");");
+            emitCode("return NULL;");
+          }
+        }
+        NodeOps.push_back(Val);
+      }
+      return NodeOps;
+    }
+    if (N->isLeaf()) {
+      // If this is an explicit register reference, handle it.
+      if (DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue())) {
+        unsigned ResNo = TmpNo++;
+        if (DI->getDef()->isSubClassOf("Register")) {
+          emitCode("SDOperand Tmp" + utostr(ResNo) + " = CurDAG->getRegister(" +
+                   ISE.getQualifiedName(DI->getDef()) + ", " +
+                   getEnumName(N->getTypeNum(0)) + ");");
+          NodeOps.push_back("Tmp" + utostr(ResNo));
+          return NodeOps;
+        } else if (DI->getDef()->getName() == "zero_reg") {
+          emitCode("SDOperand Tmp" + utostr(ResNo) +
+                   " = CurDAG->getRegister(0, " +
+                   getEnumName(N->getTypeNum(0)) + ");");
+          NodeOps.push_back("Tmp" + utostr(ResNo));
+          return NodeOps;
+        }
+      } else if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) {
+        unsigned ResNo = TmpNo++;
+        assert(N->getExtTypes().size() == 1 && "Multiple types not handled!");
+        emitCode("SDOperand Tmp" + utostr(ResNo) + 
+                 " = CurDAG->getTargetConstant(" + itostr(II->getValue()) +
+                 ", " + getEnumName(N->getTypeNum(0)) + ");");
+        NodeOps.push_back("Tmp" + utostr(ResNo));
+        return NodeOps;
+      }
+    
+#ifndef NDEBUG
+      N->dump();
+#endif
+      assert(0 && "Unknown leaf type!");
+      return NodeOps;
+    }
+
+    Record *Op = N->getOperator();
+    if (Op->isSubClassOf("Instruction")) {
+      const CodeGenTarget &CGT = ISE.getTargetInfo();
+      CodeGenInstruction &II = CGT.getInstruction(Op->getName());
+      const DAGInstruction &Inst = ISE.getInstruction(Op);
+      TreePattern *InstPat = Inst.getPattern();
+      TreePatternNode *InstPatNode =
+        isRoot ? (InstPat ? InstPat->getOnlyTree() : Pattern)
+               : (InstPat ? InstPat->getOnlyTree() : NULL);
+      if (InstPatNode && InstPatNode->getOperator()->getName() == "set") {
+        InstPatNode = InstPatNode->getChild(1);
+      }
+      bool HasVarOps     = isRoot && II.hasVariableNumberOfOperands;
+      bool HasImpInputs  = isRoot && Inst.getNumImpOperands() > 0;
+      bool HasImpResults = isRoot && Inst.getNumImpResults() > 0;
+      bool NodeHasOptInFlag = isRoot &&
+        PatternHasProperty(Pattern, SDNPOptInFlag, ISE);
+      bool NodeHasInFlag  = isRoot &&
+        PatternHasProperty(Pattern, SDNPInFlag, ISE);
+      bool NodeHasOutFlag = HasImpResults || (isRoot &&
+        PatternHasProperty(Pattern, SDNPOutFlag, ISE));
+      bool NodeHasChain = InstPatNode &&
+        PatternHasProperty(InstPatNode, SDNPHasChain, ISE);
+      bool InputHasChain = isRoot &&
+        NodeHasProperty(Pattern, SDNPHasChain, ISE);
+      unsigned NumResults = Inst.getNumResults();    
+
+      if (NodeHasOptInFlag) {
+        emitCode("bool HasInFlag = "
+           "(N.getOperand(N.getNumOperands()-1).getValueType() == MVT::Flag);");
+      }
+      if (HasVarOps)
+        emitCode("SmallVector<SDOperand, 8> Ops" + utostr(OpcNo) + ";");
+
+      // How many results is this pattern expected to produce?
+      unsigned PatResults = 0;
+      for (unsigned i = 0, e = Pattern->getExtTypes().size(); i != e; i++) {
+        MVT::ValueType VT = Pattern->getTypeNum(i);
+        if (VT != MVT::isVoid && VT != MVT::Flag)
+          PatResults++;
+      }
+
+      if (OrigChains.size() > 0) {
+        // The original input chain is being ignored. If it is not just
+        // pointing to the op that's being folded, we should create a
+        // TokenFactor with it and the chain of the folded op as the new chain.
+        // We could potentially be doing multiple levels of folding, in that
+        // case, the TokenFactor can have more operands.
+        emitCode("SmallVector<SDOperand, 8> InChains;");
+        for (unsigned i = 0, e = OrigChains.size(); i < e; ++i) {
+          emitCode("if (" + OrigChains[i].first + ".Val != " +
+                   OrigChains[i].second + ".Val) {");
+          emitCode("  AddToISelQueue(" + OrigChains[i].first + ");");
+          emitCode("  InChains.push_back(" + OrigChains[i].first + ");");
+          emitCode("}");
+        }
+        emitCode("AddToISelQueue(" + ChainName + ");");
+        emitCode("InChains.push_back(" + ChainName + ");");
+        emitCode(ChainName + " = CurDAG->getNode(ISD::TokenFactor, MVT::Other, "
+                 "&InChains[0], InChains.size());");
+      }
+
+      // 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.
+      std::vector<std::string> AllOps;
+      unsigned NumEAInputs = 0; // # of synthesized 'execute always' inputs.
+      for (unsigned ChildNo = 0, InstOpNo = NumResults;
+           InstOpNo != II.OperandList.size(); ++InstOpNo) {
+        std::vector<std::string> Ops;
+        
+        // If this is a normal operand or a predicate operand without
+        // 'execute always', emit it.
+        Record *OperandNode = II.OperandList[InstOpNo].Rec;
+        if ((!OperandNode->isSubClassOf("PredicateOperand") &&
+             !OperandNode->isSubClassOf("OptionalDefOperand")) ||
+            ISE.getDefaultOperand(OperandNode).DefaultOps.empty()) {
+          Ops = EmitResultCode(N->getChild(ChildNo), RetSelected, 
+                               InFlagDecled, ResNodeDecled);
+          AllOps.insert(AllOps.end(), Ops.begin(), Ops.end());
+          ++ChildNo;
+        } else {
+          // Otherwise, this is a predicate or optional def operand, emit the
+          // 'default ops' operands.
+          const DAGDefaultOperand &DefaultOp =
+            ISE.getDefaultOperand(II.OperandList[InstOpNo].Rec);
+          for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i) {
+            Ops = EmitResultCode(DefaultOp.DefaultOps[i], RetSelected, 
+                                 InFlagDecled, ResNodeDecled);
+            AllOps.insert(AllOps.end(), Ops.begin(), Ops.end());
+            NumEAInputs += Ops.size();
+          }
+        }
+      }
+
+      // Emit all the chain and CopyToReg stuff.
+      bool ChainEmitted = NodeHasChain;
+      if (NodeHasChain)
+        emitCode("AddToISelQueue(" + ChainName + ");");
+      if (NodeHasInFlag || HasImpInputs)
+        EmitInFlagSelectCode(Pattern, "N", ChainEmitted,
+                             InFlagDecled, ResNodeDecled, true);
+      if (NodeHasOptInFlag || NodeHasInFlag || HasImpInputs) {
+        if (!InFlagDecled) {
+          emitCode("SDOperand InFlag(0, 0);");
+          InFlagDecled = true;
+        }
+        if (NodeHasOptInFlag) {
+          emitCode("if (HasInFlag) {");
+          emitCode("  InFlag = N.getOperand(N.getNumOperands()-1);");
+          emitCode("  AddToISelQueue(InFlag);");
+          emitCode("}");
+        }
+      }
+
+      unsigned ResNo = TmpNo++;
+      if (!isRoot || InputHasChain || NodeHasChain || NodeHasOutFlag ||
+          NodeHasOptInFlag) {
+        std::string Code;
+        std::string Code2;
+        std::string NodeName;
+        if (!isRoot) {
+          NodeName = "Tmp" + utostr(ResNo);
+          Code2 = "SDOperand " + NodeName + " = SDOperand(";
+        } else {
+          NodeName = "ResNode";
+          if (!ResNodeDecled) {
+            Code2 = "SDNode *" + NodeName + " = ";
+            ResNodeDecled = true;
+          } else
+            Code2 = NodeName + " = ";
+        }
+
+        Code = "CurDAG->getTargetNode(Opc" + utostr(OpcNo);
+        unsigned OpsNo = OpcNo;
+        emitOpcode(II.Namespace + "::" + II.TheDef->getName());
+
+        // Output order: results, chain, flags
+        // Result types.
+        if (NumResults > 0 && N->getTypeNum(0) != MVT::isVoid) {
+          Code += ", VT" + utostr(VTNo);
+          emitVT(getEnumName(N->getTypeNum(0)));
+        }
+        if (NodeHasChain)
+          Code += ", MVT::Other";
+        if (NodeHasOutFlag)
+          Code += ", MVT::Flag";
+
+        // Figure out how many fixed inputs the node has.  This is important to
+        // know which inputs are the variable ones if present.
+        unsigned NumInputs = AllOps.size();
+        NumInputs += NodeHasChain;
+        
+        // Inputs.
+        if (HasVarOps) {
+          for (unsigned i = 0, e = AllOps.size(); i != e; ++i)
+            emitCode("Ops" + utostr(OpsNo) + ".push_back(" + AllOps[i] + ");");
+          AllOps.clear();
+        }
+
+        if (HasVarOps) {
+          // Figure out whether any operands at the end of the op list are not
+          // part of the variable section.
+          std::string EndAdjust;
+          if (NodeHasInFlag || HasImpInputs)
+            EndAdjust = "-1";  // Always has one flag.
+          else if (NodeHasOptInFlag)
+            EndAdjust = "-(HasInFlag?1:0)"; // May have a flag.
+
+          emitCode("for (unsigned i = " + utostr(NumInputs - NumEAInputs) +
+                   ", e = N.getNumOperands()" + EndAdjust + "; i != e; ++i) {");
+
+          emitCode("  AddToISelQueue(N.getOperand(i));");
+          emitCode("  Ops" + utostr(OpsNo) + ".push_back(N.getOperand(i));");
+          emitCode("}");
+        }
+
+        if (NodeHasChain) {
+          if (HasVarOps)
+            emitCode("Ops" + utostr(OpsNo) + ".push_back(" + ChainName + ");");
+          else
+            AllOps.push_back(ChainName);
+        }
+
+        if (HasVarOps) {
+          if (NodeHasInFlag || HasImpInputs)
+            emitCode("Ops" + utostr(OpsNo) + ".push_back(InFlag);");
+          else if (NodeHasOptInFlag) {
+            emitCode("if (HasInFlag)");
+            emitCode("  Ops" + utostr(OpsNo) + ".push_back(InFlag);");
+          }
+          Code += ", &Ops" + utostr(OpsNo) + "[0], Ops" + utostr(OpsNo) +
+            ".size()";
+        } else if (NodeHasInFlag || NodeHasOptInFlag || HasImpInputs)
+            AllOps.push_back("InFlag");
+
+        unsigned NumOps = AllOps.size();
+        if (NumOps) {
+          if (!NodeHasOptInFlag && NumOps < 4) {
+            for (unsigned i = 0; i != NumOps; ++i)
+              Code += ", " + AllOps[i];
+          } else {
+            std::string OpsCode = "SDOperand Ops" + utostr(OpsNo) + "[] = { ";
+            for (unsigned i = 0; i != NumOps; ++i) {
+              OpsCode += AllOps[i];
+              if (i != NumOps-1)
+                OpsCode += ", ";
+            }
+            emitCode(OpsCode + " };");
+            Code += ", Ops" + utostr(OpsNo) + ", ";
+            if (NodeHasOptInFlag) {
+              Code += "HasInFlag ? ";
+              Code += utostr(NumOps) + " : " + utostr(NumOps-1);
+            } else
+              Code += utostr(NumOps);
+          }
+        }
+            
+        if (!isRoot)
+          Code += "), 0";
+        emitCode(Code2 + Code + ");");
+
+        if (NodeHasChain)
+          // Remember which op produces the chain.
+          if (!isRoot)
+            emitCode(ChainName + " = SDOperand(" + NodeName +
+                     ".Val, " + utostr(PatResults) + ");");
+          else
+            emitCode(ChainName + " = SDOperand(" + NodeName +
+                     ", " + utostr(PatResults) + ");");
+
+        if (!isRoot) {
+          NodeOps.push_back("Tmp" + utostr(ResNo));
+          return NodeOps;
+        }
+
+        bool NeedReplace = false;
+        if (NodeHasOutFlag) {
+          if (!InFlagDecled) {
+            emitCode("SDOperand InFlag = SDOperand(ResNode, " + 
+                     utostr(NumResults + (unsigned)NodeHasChain) + ");");
+            InFlagDecled = true;
+          } else
+            emitCode("InFlag = SDOperand(ResNode, " + 
+                     utostr(NumResults + (unsigned)NodeHasChain) + ");");
+        }
+
+        if (HasImpResults && EmitCopyFromRegs(N, ResNodeDecled, ChainEmitted)) {
+          emitCode("ReplaceUses(SDOperand(N.Val, 0), SDOperand(ResNode, 0));");
+          NumResults = 1;
+        }
+
+        if (FoldedChains.size() > 0) {
+          std::string Code;
+          for (unsigned j = 0, e = FoldedChains.size(); j < e; j++)
+            emitCode("ReplaceUses(SDOperand(" +
+                     FoldedChains[j].first + ".Val, " + 
+                     utostr(FoldedChains[j].second) + "), SDOperand(ResNode, " +
+                     utostr(NumResults) + "));");
+          NeedReplace = true;
+        }
+
+        if (NodeHasOutFlag) {
+          emitCode("ReplaceUses(SDOperand(N.Val, " +
+                   utostr(PatResults + (unsigned)InputHasChain) +"), InFlag);");
+          NeedReplace = true;
+        }
+
+        if (NeedReplace) {
+          for (unsigned i = 0; i < NumResults; i++)
+            emitCode("ReplaceUses(SDOperand(N.Val, " +
+                     utostr(i) + "), SDOperand(ResNode, " + utostr(i) + "));");
+          if (InputHasChain)
+            emitCode("ReplaceUses(SDOperand(N.Val, " + 
+                     utostr(PatResults) + "), SDOperand(" + ChainName + ".Val, "
+                     + ChainName + ".ResNo" + "));");
+        } else
+          RetSelected = true;
+
+        // User does not expect the instruction would produce a chain!
+        if ((!InputHasChain && NodeHasChain) && NodeHasOutFlag) {
+          ;
+        } else if (InputHasChain && !NodeHasChain) {
+          // One of the inner node produces a chain.
+          if (NodeHasOutFlag)
+	    emitCode("ReplaceUses(SDOperand(N.Val, " + utostr(PatResults+1) +
+		     "), SDOperand(ResNode, N.ResNo-1));");
+	  for (unsigned i = 0; i < PatResults; ++i)
+	    emitCode("ReplaceUses(SDOperand(N.Val, " + utostr(i) +
+		     "), SDOperand(ResNode, " + utostr(i) + "));");
+	  emitCode("ReplaceUses(SDOperand(N.Val, " + utostr(PatResults) +
+		   "), " + ChainName + ");");
+	  RetSelected = false;
+        }
+
+	if (RetSelected)
+	  emitCode("return ResNode;");
+	else
+	  emitCode("return NULL;");
+      } else {
+        std::string Code = "return CurDAG->SelectNodeTo(N.Val, Opc" +
+          utostr(OpcNo);
+        if (N->getTypeNum(0) != MVT::isVoid)
+          Code += ", VT" + utostr(VTNo);
+        if (NodeHasOutFlag)
+          Code += ", MVT::Flag";
+
+        if (NodeHasInFlag || NodeHasOptInFlag || HasImpInputs)
+          AllOps.push_back("InFlag");
+
+        unsigned NumOps = AllOps.size();
+        if (NumOps) {
+          if (!NodeHasOptInFlag && NumOps < 4) {
+            for (unsigned i = 0; i != NumOps; ++i)
+              Code += ", " + AllOps[i];
+          } else {
+            std::string OpsCode = "SDOperand Ops" + utostr(OpcNo) + "[] = { ";
+            for (unsigned i = 0; i != NumOps; ++i) {
+              OpsCode += AllOps[i];
+              if (i != NumOps-1)
+                OpsCode += ", ";
+            }
+            emitCode(OpsCode + " };");
+            Code += ", Ops" + utostr(OpcNo) + ", ";
+            Code += utostr(NumOps);
+          }
+        }
+        emitCode(Code + ");");
+        emitOpcode(II.Namespace + "::" + II.TheDef->getName());
+        if (N->getTypeNum(0) != MVT::isVoid)
+          emitVT(getEnumName(N->getTypeNum(0)));
+      }
+
+      return NodeOps;
+    } else if (Op->isSubClassOf("SDNodeXForm")) {
+      assert(N->getNumChildren() == 1 && "node xform should have one child!");
+      // PatLeaf node - the operand may or may not be a leaf node. But it should
+      // behave like one.
+      std::vector<std::string> Ops =
+        EmitResultCode(N->getChild(0), RetSelected, InFlagDecled,
+                       ResNodeDecled, true);
+      unsigned ResNo = TmpNo++;
+      emitCode("SDOperand Tmp" + utostr(ResNo) + " = Transform_" + Op->getName()
+               + "(" + Ops.back() + ".Val);");
+      NodeOps.push_back("Tmp" + utostr(ResNo));
+      if (isRoot)
+        emitCode("return Tmp" + utostr(ResNo) + ".Val;");
+      return NodeOps;
+    } else {
+      N->dump();
+      cerr << "\n";
+      throw std::string("Unknown node in result pattern!");
+    }
+  }
+
+  /// InsertOneTypeCheck - Insert a type-check for an unresolved type in 'Pat'
+  /// and add it to the tree. 'Pat' and 'Other' are isomorphic trees except that 
+  /// 'Pat' may be missing types.  If we find an unresolved type to add a check
+  /// for, this returns true otherwise false if Pat has all types.
+  bool InsertOneTypeCheck(TreePatternNode *Pat, TreePatternNode *Other,
+                          const std::string &Prefix, bool isRoot = false) {
+    // Did we find one?
+    if (Pat->getExtTypes() != Other->getExtTypes()) {
+      // Move a type over from 'other' to 'pat'.
+      Pat->setTypes(Other->getExtTypes());
+      // The top level node type is checked outside of the select function.
+      if (!isRoot)
+        emitCheck(Prefix + ".Val->getValueType(0) == " +
+                  getName(Pat->getTypeNum(0)));
+      return true;
+    }
+  
+    unsigned OpNo =
+      (unsigned) NodeHasProperty(Pat, SDNPHasChain, ISE);
+    for (unsigned i = 0, e = Pat->getNumChildren(); i != e; ++i, ++OpNo)
+      if (InsertOneTypeCheck(Pat->getChild(i), Other->getChild(i),
+                             Prefix + utostr(OpNo)))
+        return true;
+    return false;
+  }
+
+private:
+  /// EmitInFlagSelectCode - Emit the flag operands for the DAG that is
+  /// being built.
+  void EmitInFlagSelectCode(TreePatternNode *N, const std::string &RootName,
+                            bool &ChainEmitted, bool &InFlagDecled,
+                            bool &ResNodeDecled, bool isRoot = false) {
+    const CodeGenTarget &T = ISE.getTargetInfo();
+    unsigned OpNo =
+      (unsigned) NodeHasProperty(N, SDNPHasChain, ISE);
+    bool HasInFlag = NodeHasProperty(N, SDNPInFlag, ISE);
+    for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i, ++OpNo) {
+      TreePatternNode *Child = N->getChild(i);
+      if (!Child->isLeaf()) {
+        EmitInFlagSelectCode(Child, RootName + utostr(OpNo), ChainEmitted,
+                             InFlagDecled, ResNodeDecled);
+      } else {
+        if (DefInit *DI = dynamic_cast<DefInit*>(Child->getLeafValue())) {
+          if (!Child->getName().empty()) {
+            std::string Name = RootName + utostr(OpNo);
+            if (Duplicates.find(Name) != Duplicates.end())
+              // A duplicate! Do not emit a copy for this node.
+              continue;
+          }
+
+          Record *RR = DI->getDef();
+          if (RR->isSubClassOf("Register")) {
+            MVT::ValueType RVT = getRegisterValueType(RR, T);
+            if (RVT == MVT::Flag) {
+              if (!InFlagDecled) {
+                emitCode("SDOperand InFlag = " + RootName + utostr(OpNo) + ";");
+                InFlagDecled = true;
+              } else
+                emitCode("InFlag = " + RootName + utostr(OpNo) + ";");
+              emitCode("AddToISelQueue(InFlag);");
+            } else {
+              if (!ChainEmitted) {
+                emitCode("SDOperand Chain = CurDAG->getEntryNode();");
+                ChainName = "Chain";
+                ChainEmitted = true;
+              }
+              emitCode("AddToISelQueue(" + RootName + utostr(OpNo) + ");");
+              if (!InFlagDecled) {
+                emitCode("SDOperand InFlag(0, 0);");
+                InFlagDecled = true;
+              }
+              std::string Decl = (!ResNodeDecled) ? "SDNode *" : "";
+              emitCode(Decl + "ResNode = CurDAG->getCopyToReg(" + ChainName +
+                       ", " + ISE.getQualifiedName(RR) +
+                       ", " +  RootName + utostr(OpNo) + ", InFlag).Val;");
+              ResNodeDecled = true;
+              emitCode(ChainName + " = SDOperand(ResNode, 0);");
+              emitCode("InFlag = SDOperand(ResNode, 1);");
+            }
+          }
+        }
+      }
+    }
+
+    if (HasInFlag) {
+      if (!InFlagDecled) {
+        emitCode("SDOperand InFlag = " + RootName +
+               ".getOperand(" + utostr(OpNo) + ");");
+        InFlagDecled = true;
+      } else
+        emitCode("InFlag = " + RootName +
+               ".getOperand(" + utostr(OpNo) + ");");
+      emitCode("AddToISelQueue(InFlag);");
+    }
+  }
+
+  /// EmitCopyFromRegs - Emit code to copy result to physical registers
+  /// as specified by the instruction. It returns true if any copy is
+  /// emitted.
+  bool EmitCopyFromRegs(TreePatternNode *N, bool &ResNodeDecled,
+                        bool &ChainEmitted) {
+    bool RetVal = false;
+    Record *Op = N->getOperator();
+    if (Op->isSubClassOf("Instruction")) {
+      const DAGInstruction &Inst = ISE.getInstruction(Op);
+      const CodeGenTarget &CGT = ISE.getTargetInfo();
+      unsigned NumImpResults  = Inst.getNumImpResults();
+      for (unsigned i = 0; i < NumImpResults; i++) {
+        Record *RR = Inst.getImpResult(i);
+        if (RR->isSubClassOf("Register")) {
+          MVT::ValueType RVT = getRegisterValueType(RR, CGT);
+          if (RVT != MVT::Flag) {
+            if (!ChainEmitted) {
+              emitCode("SDOperand Chain = CurDAG->getEntryNode();");
+              ChainEmitted = true;
+              ChainName = "Chain";
+            }
+            std::string Decl = (!ResNodeDecled) ? "SDNode *" : "";
+            emitCode(Decl + "ResNode = CurDAG->getCopyFromReg(" + ChainName +
+                     ", " + ISE.getQualifiedName(RR) + ", " + getEnumName(RVT) +
+                     ", InFlag).Val;");
+            ResNodeDecled = true;
+            emitCode(ChainName + " = SDOperand(ResNode, 1);");
+            emitCode("InFlag = SDOperand(ResNode, 2);");
+            RetVal = true;
+          }
+        }
+      }
+    }
+    return RetVal;
+  }
+};
+
+/// EmitCodeForPattern - Given a pattern to match, emit code to the specified
+/// stream to match the pattern, and generate the code for the match if it
+/// succeeds.  Returns true if the pattern is not guaranteed to match.
+void DAGISelEmitter::GenerateCodeForPattern(PatternToMatch &Pattern,
+                  std::vector<std::pair<unsigned, std::string> > &GeneratedCode,
+                                           std::set<std::string> &GeneratedDecl,
+                                        std::vector<std::string> &TargetOpcodes,
+                                          std::vector<std::string> &TargetVTs) {
+  PatternCodeEmitter Emitter(*this, Pattern.getPredicates(),
+                             Pattern.getSrcPattern(), Pattern.getDstPattern(),
+                             GeneratedCode, GeneratedDecl,
+                             TargetOpcodes, TargetVTs);
+
+  // Emit the matcher, capturing named arguments in VariableMap.
+  bool FoundChain = false;
+  Emitter.EmitMatchCode(Pattern.getSrcPattern(), NULL, "N", "", FoundChain);
+
+  // TP - Get *SOME* tree pattern, we don't care which.
+  TreePattern &TP = *PatternFragments.begin()->second;
+  
+  // At this point, we know that we structurally match the pattern, but the
+  // types of the nodes may not match.  Figure out the fewest number of type 
+  // comparisons we need to emit.  For example, if there is only one integer
+  // type supported by a target, there should be no type comparisons at all for
+  // integer patterns!
+  //
+  // To figure out the fewest number of type checks needed, clone the pattern,
+  // remove the types, then perform type inference on the pattern as a whole.
+  // If there are unresolved types, emit an explicit check for those types,
+  // apply the type to the tree, then rerun type inference.  Iterate until all
+  // types are resolved.
+  //
+  TreePatternNode *Pat = Pattern.getSrcPattern()->clone();
+  RemoveAllTypes(Pat);
+  
+  do {
+    // Resolve/propagate as many types as possible.
+    try {
+      bool MadeChange = true;
+      while (MadeChange)
+        MadeChange = Pat->ApplyTypeConstraints(TP,
+                                               true/*Ignore reg constraints*/);
+    } catch (...) {
+      assert(0 && "Error: could not find consistent types for something we"
+             " already decided was ok!");
+      abort();
+    }
+
+    // Insert a check for an unresolved type and add it to the tree.  If we find
+    // an unresolved type to add a check for, this returns true and we iterate,
+    // otherwise we are done.
+  } while (Emitter.InsertOneTypeCheck(Pat, Pattern.getSrcPattern(), "N", true));
+
+  Emitter.EmitResultCode(Pattern.getDstPattern(),
+                         false, false, false, false, true);
+  delete Pat;
+}
+
+/// EraseCodeLine - Erase one code line from all of the patterns.  If removing
+/// a line causes any of them to be empty, remove them and return true when
+/// done.
+static bool EraseCodeLine(std::vector<std::pair<PatternToMatch*, 
+                          std::vector<std::pair<unsigned, std::string> > > >
+                          &Patterns) {
+  bool ErasedPatterns = false;
+  for (unsigned i = 0, e = Patterns.size(); i != e; ++i) {
+    Patterns[i].second.pop_back();
+    if (Patterns[i].second.empty()) {
+      Patterns.erase(Patterns.begin()+i);
+      --i; --e;
+      ErasedPatterns = true;
+    }
+  }
+  return ErasedPatterns;
+}
+
+/// EmitPatterns - Emit code for at least one pattern, but try to group common
+/// code together between the patterns.
+void DAGISelEmitter::EmitPatterns(std::vector<std::pair<PatternToMatch*, 
+                              std::vector<std::pair<unsigned, std::string> > > >
+                                  &Patterns, unsigned Indent,
+                                  std::ostream &OS) {
+  typedef std::pair<unsigned, std::string> CodeLine;
+  typedef std::vector<CodeLine> CodeList;
+  typedef std::vector<std::pair<PatternToMatch*, CodeList> > PatternList;
+  
+  if (Patterns.empty()) return;
+  
+  // Figure out how many patterns share the next code line.  Explicitly copy
+  // FirstCodeLine so that we don't invalidate a reference when changing
+  // Patterns.
+  const CodeLine FirstCodeLine = Patterns.back().second.back();
+  unsigned LastMatch = Patterns.size()-1;
+  while (LastMatch != 0 && Patterns[LastMatch-1].second.back() == FirstCodeLine)
+    --LastMatch;
+  
+  // If not all patterns share this line, split the list into two pieces.  The
+  // first chunk will use this line, the second chunk won't.
+  if (LastMatch != 0) {
+    PatternList Shared(Patterns.begin()+LastMatch, Patterns.end());
+    PatternList Other(Patterns.begin(), Patterns.begin()+LastMatch);
+    
+    // FIXME: Emit braces?
+    if (Shared.size() == 1) {
+      PatternToMatch &Pattern = *Shared.back().first;
+      OS << "\n" << std::string(Indent, ' ') << "// Pattern: ";
+      Pattern.getSrcPattern()->print(OS);
+      OS << "\n" << std::string(Indent, ' ') << "// Emits: ";
+      Pattern.getDstPattern()->print(OS);
+      OS << "\n";
+      unsigned AddedComplexity = Pattern.getAddedComplexity();
+      OS << std::string(Indent, ' ') << "// Pattern complexity = "
+         << getPatternSize(Pattern.getSrcPattern(), *this) + AddedComplexity
+         << "  cost = "
+         << getResultPatternCost(Pattern.getDstPattern(), *this)
+         << "  size = "
+         << getResultPatternSize(Pattern.getDstPattern(), *this) << "\n";
+    }
+    if (FirstCodeLine.first != 1) {
+      OS << std::string(Indent, ' ') << "{\n";
+      Indent += 2;
+    }
+    EmitPatterns(Shared, Indent, OS);
+    if (FirstCodeLine.first != 1) {
+      Indent -= 2;
+      OS << std::string(Indent, ' ') << "}\n";
+    }
+    
+    if (Other.size() == 1) {
+      PatternToMatch &Pattern = *Other.back().first;
+      OS << "\n" << std::string(Indent, ' ') << "// Pattern: ";
+      Pattern.getSrcPattern()->print(OS);
+      OS << "\n" << std::string(Indent, ' ') << "// Emits: ";
+      Pattern.getDstPattern()->print(OS);
+      OS << "\n";
+      unsigned AddedComplexity = Pattern.getAddedComplexity();
+      OS << std::string(Indent, ' ') << "// Pattern complexity = "
+         << getPatternSize(Pattern.getSrcPattern(), *this) + AddedComplexity
+         << "  cost = "
+         << getResultPatternCost(Pattern.getDstPattern(), *this)
+         << "  size = "
+         << getResultPatternSize(Pattern.getDstPattern(), *this) << "\n";
+    }
+    EmitPatterns(Other, Indent, OS);
+    return;
+  }
+  
+  // Remove this code from all of the patterns that share it.
+  bool ErasedPatterns = EraseCodeLine(Patterns);
+  
+  bool isPredicate = FirstCodeLine.first == 1;
+  
+  // Otherwise, every pattern in the list has this line.  Emit it.
+  if (!isPredicate) {
+    // Normal code.
+    OS << std::string(Indent, ' ') << FirstCodeLine.second << "\n";
+  } else {
+    OS << std::string(Indent, ' ') << "if (" << FirstCodeLine.second;
+    
+    // If the next code line is another predicate, and if all of the pattern
+    // in this group share the same next line, emit it inline now.  Do this
+    // until we run out of common predicates.
+    while (!ErasedPatterns && Patterns.back().second.back().first == 1) {
+      // Check that all of fhe patterns in Patterns end with the same predicate.
+      bool AllEndWithSamePredicate = true;
+      for (unsigned i = 0, e = Patterns.size(); i != e; ++i)
+        if (Patterns[i].second.back() != Patterns.back().second.back()) {
+          AllEndWithSamePredicate = false;
+          break;
+        }
+      // If all of the predicates aren't the same, we can't share them.
+      if (!AllEndWithSamePredicate) break;
+      
+      // Otherwise we can.  Emit it shared now.
+      OS << " &&\n" << std::string(Indent+4, ' ')
+         << Patterns.back().second.back().second;
+      ErasedPatterns = EraseCodeLine(Patterns);
+    }
+    
+    OS << ") {\n";
+    Indent += 2;
+  }
+  
+  EmitPatterns(Patterns, Indent, OS);
+  
+  if (isPredicate)
+    OS << std::string(Indent-2, ' ') << "}\n";
+}
+
+static std::string getOpcodeName(Record *Op, DAGISelEmitter &ISE) {
+  const SDNodeInfo &OpcodeInfo = ISE.getSDNodeInfo(Op);
+  return OpcodeInfo.getEnumName();
+}
+
+static std::string getLegalCName(std::string OpName) {
+  std::string::size_type pos = OpName.find("::");
+  if (pos != std::string::npos)
+    OpName.replace(pos, 2, "_");
+  return OpName;
+}
+
+void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
+  // Get the namespace to insert instructions into.  Make sure not to pick up
+  // "TargetInstrInfo" by accidentally getting the namespace off the PHI
+  // instruction or something.
+  std::string InstNS;
+  for (CodeGenTarget::inst_iterator i = Target.inst_begin(),
+       e = Target.inst_end(); i != e; ++i) {
+    InstNS = i->second.Namespace;
+    if (InstNS != "TargetInstrInfo")
+      break;
+  }
+  
+  if (!InstNS.empty()) InstNS += "::";
+  
+  // Group the patterns by their top-level opcodes.
+  std::map<std::string, std::vector<PatternToMatch*> > PatternsByOpcode;
+  // All unique target node emission functions.
+  std::map<std::string, unsigned> EmitFunctions;
+  for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i) {
+    TreePatternNode *Node = PatternsToMatch[i].getSrcPattern();
+    if (!Node->isLeaf()) {
+      PatternsByOpcode[getOpcodeName(Node->getOperator(), *this)].
+        push_back(&PatternsToMatch[i]);
+    } else {
+      const ComplexPattern *CP;
+      if (dynamic_cast<IntInit*>(Node->getLeafValue())) {
+        PatternsByOpcode[getOpcodeName(getSDNodeNamed("imm"), *this)].
+          push_back(&PatternsToMatch[i]);
+      } else if ((CP = NodeGetComplexPattern(Node, *this))) {
+        std::vector<Record*> OpNodes = CP->getRootNodes();
+        for (unsigned j = 0, e = OpNodes.size(); j != e; j++) {
+          PatternsByOpcode[getOpcodeName(OpNodes[j], *this)]
+            .insert(PatternsByOpcode[getOpcodeName(OpNodes[j], *this)].begin(),
+                    &PatternsToMatch[i]);
+        }
+      } else {
+        cerr << "Unrecognized opcode '";
+        Node->dump();
+        cerr << "' on tree pattern '";
+        cerr << PatternsToMatch[i].getDstPattern()->getOperator()->getName();
+        cerr << "'!\n";
+        exit(1);
+      }
+    }
+  }
+
+  // For each opcode, there might be multiple select functions, one per
+  // ValueType of the node (or its first operand if it doesn't produce a
+  // non-chain result.
+  std::map<std::string, std::vector<std::string> > OpcodeVTMap;
+
+  // Emit one Select_* method for each top-level opcode.  We do this instead of
+  // emitting one giant switch statement to support compilers where this will
+  // result in the recursive functions taking less stack space.
+  for (std::map<std::string, std::vector<PatternToMatch*> >::iterator
+         PBOI = PatternsByOpcode.begin(), E = PatternsByOpcode.end();
+       PBOI != E; ++PBOI) {
+    const std::string &OpName = PBOI->first;
+    std::vector<PatternToMatch*> &PatternsOfOp = PBOI->second;
+    assert(!PatternsOfOp.empty() && "No patterns but map has entry?");
+
+    // We want to emit all of the matching code now.  However, we want to emit
+    // the matches in order of minimal cost.  Sort the patterns so the least
+    // cost one is at the start.
+    std::stable_sort(PatternsOfOp.begin(), PatternsOfOp.end(),
+                     PatternSortingPredicate(*this));
+
+    // Split them into groups by type.
+    std::map<MVT::ValueType, std::vector<PatternToMatch*> > PatternsByType;
+    for (unsigned i = 0, e = PatternsOfOp.size(); i != e; ++i) {
+      PatternToMatch *Pat = PatternsOfOp[i];
+      TreePatternNode *SrcPat = Pat->getSrcPattern();
+      MVT::ValueType VT = SrcPat->getTypeNum(0);
+      std::map<MVT::ValueType, std::vector<PatternToMatch*> >::iterator TI = 
+        PatternsByType.find(VT);
+      if (TI != PatternsByType.end())
+        TI->second.push_back(Pat);
+      else {
+        std::vector<PatternToMatch*> PVec;
+        PVec.push_back(Pat);
+        PatternsByType.insert(std::make_pair(VT, PVec));
+      }
+    }
+
+    for (std::map<MVT::ValueType, std::vector<PatternToMatch*> >::iterator
+           II = PatternsByType.begin(), EE = PatternsByType.end(); II != EE;
+         ++II) {
+      MVT::ValueType OpVT = II->first;
+      std::vector<PatternToMatch*> &Patterns = II->second;
+      typedef std::vector<std::pair<unsigned,std::string> > CodeList;
+      typedef std::vector<std::pair<unsigned,std::string> >::iterator CodeListI;
+    
+      std::vector<std::pair<PatternToMatch*, CodeList> > CodeForPatterns;
+      std::vector<std::vector<std::string> > PatternOpcodes;
+      std::vector<std::vector<std::string> > PatternVTs;
+      std::vector<std::set<std::string> > PatternDecls;
+      for (unsigned i = 0, e = Patterns.size(); i != e; ++i) {
+        CodeList GeneratedCode;
+        std::set<std::string> GeneratedDecl;
+        std::vector<std::string> TargetOpcodes;
+        std::vector<std::string> TargetVTs;
+        GenerateCodeForPattern(*Patterns[i], GeneratedCode, GeneratedDecl,
+                               TargetOpcodes, TargetVTs);
+        CodeForPatterns.push_back(std::make_pair(Patterns[i], GeneratedCode));
+        PatternDecls.push_back(GeneratedDecl);
+        PatternOpcodes.push_back(TargetOpcodes);
+        PatternVTs.push_back(TargetVTs);
+      }
+    
+      // Scan the code to see if all of the patterns are reachable and if it is
+      // possible that the last one might not match.
+      bool mightNotMatch = true;
+      for (unsigned i = 0, e = CodeForPatterns.size(); i != e; ++i) {
+        CodeList &GeneratedCode = CodeForPatterns[i].second;
+        mightNotMatch = false;
+
+        for (unsigned j = 0, e = GeneratedCode.size(); j != e; ++j) {
+          if (GeneratedCode[j].first == 1) { // predicate.
+            mightNotMatch = true;
+            break;
+          }
+        }
+      
+        // If this pattern definitely matches, and if it isn't the last one, the
+        // patterns after it CANNOT ever match.  Error out.
+        if (mightNotMatch == false && i != CodeForPatterns.size()-1) {
+          cerr << "Pattern '";
+          CodeForPatterns[i].first->getSrcPattern()->print(*cerr.stream());
+          cerr << "' is impossible to select!\n";
+          exit(1);
+        }
+      }
+
+      // Factor target node emission code (emitted by EmitResultCode) into
+      // separate functions. Uniquing and share them among all instruction
+      // selection routines.
+      for (unsigned i = 0, e = CodeForPatterns.size(); i != e; ++i) {
+        CodeList &GeneratedCode = CodeForPatterns[i].second;
+        std::vector<std::string> &TargetOpcodes = PatternOpcodes[i];
+        std::vector<std::string> &TargetVTs = PatternVTs[i];
+        std::set<std::string> Decls = PatternDecls[i];
+        std::vector<std::string> AddedInits;
+        int CodeSize = (int)GeneratedCode.size();
+        int LastPred = -1;
+        for (int j = CodeSize-1; j >= 0; --j) {
+          if (LastPred == -1 && GeneratedCode[j].first == 1)
+            LastPred = j;
+          else if (LastPred != -1 && GeneratedCode[j].first == 2)
+            AddedInits.push_back(GeneratedCode[j].second);
+        }
+
+        std::string CalleeCode = "(const SDOperand &N";
+        std::string CallerCode = "(N";
+        for (unsigned j = 0, e = TargetOpcodes.size(); j != e; ++j) {
+          CalleeCode += ", unsigned Opc" + utostr(j);
+          CallerCode += ", " + TargetOpcodes[j];
+        }
+        for (unsigned j = 0, e = TargetVTs.size(); j != e; ++j) {
+          CalleeCode += ", MVT::ValueType VT" + utostr(j);
+          CallerCode += ", " + TargetVTs[j];
+        }
+        for (std::set<std::string>::iterator
+               I = Decls.begin(), E = Decls.end(); I != E; ++I) {
+          std::string Name = *I;
+          CalleeCode += ", SDOperand &" + Name;
+          CallerCode += ", " + Name;
+        }
+        CallerCode += ");";
+        CalleeCode += ") ";
+        // Prevent emission routines from being inlined to reduce selection
+        // routines stack frame sizes.
+        CalleeCode += "DISABLE_INLINE ";
+        CalleeCode += "{\n";
+
+        for (std::vector<std::string>::const_reverse_iterator
+               I = AddedInits.rbegin(), E = AddedInits.rend(); I != E; ++I)
+          CalleeCode += "  " + *I + "\n";
+
+        for (int j = LastPred+1; j < CodeSize; ++j)
+          CalleeCode += "  " + GeneratedCode[j].second + "\n";
+        for (int j = LastPred+1; j < CodeSize; ++j)
+          GeneratedCode.pop_back();
+        CalleeCode += "}\n";
+
+        // Uniquing the emission routines.
+        unsigned EmitFuncNum;
+        std::map<std::string, unsigned>::iterator EFI =
+          EmitFunctions.find(CalleeCode);
+        if (EFI != EmitFunctions.end()) {
+          EmitFuncNum = EFI->second;
+        } else {
+          EmitFuncNum = EmitFunctions.size();
+          EmitFunctions.insert(std::make_pair(CalleeCode, EmitFuncNum));
+          OS << "SDNode *Emit_" << utostr(EmitFuncNum) << CalleeCode;
+        }
+
+        // Replace the emission code within selection routines with calls to the
+        // emission functions.
+        CallerCode = "return Emit_" + utostr(EmitFuncNum) + CallerCode;
+        GeneratedCode.push_back(std::make_pair(false, CallerCode));
+      }
+
+      // Print function.
+      std::string OpVTStr;
+      if (OpVT == MVT::iPTR) {
+        OpVTStr = "_iPTR";
+      } else if (OpVT == MVT::isVoid) {
+        // Nodes with a void result actually have a first result type of either
+        // Other (a chain) or Flag.  Since there is no one-to-one mapping from
+        // void to this case, we handle it specially here.
+      } else {
+        OpVTStr = "_" + getEnumName(OpVT).substr(5);  // Skip 'MVT::'
+      }
+      std::map<std::string, std::vector<std::string> >::iterator OpVTI =
+        OpcodeVTMap.find(OpName);
+      if (OpVTI == OpcodeVTMap.end()) {
+        std::vector<std::string> VTSet;
+        VTSet.push_back(OpVTStr);
+        OpcodeVTMap.insert(std::make_pair(OpName, VTSet));
+      } else
+        OpVTI->second.push_back(OpVTStr);
+
+      OS << "SDNode *Select_" << getLegalCName(OpName)
+         << OpVTStr << "(const SDOperand &N) {\n";    
+
+      // Loop through and reverse all of the CodeList vectors, as we will be
+      // accessing them from their logical front, but accessing the end of a
+      // vector is more efficient.
+      for (unsigned i = 0, e = CodeForPatterns.size(); i != e; ++i) {
+        CodeList &GeneratedCode = CodeForPatterns[i].second;
+        std::reverse(GeneratedCode.begin(), GeneratedCode.end());
+      }
+    
+      // Next, reverse the list of patterns itself for the same reason.
+      std::reverse(CodeForPatterns.begin(), CodeForPatterns.end());
+    
+      // Emit all of the patterns now, grouped together to share code.
+      EmitPatterns(CodeForPatterns, 2, OS);
+    
+      // If the last pattern has predicates (which could fail) emit code to
+      // catch the case where nothing handles a pattern.
+      if (mightNotMatch) {
+        OS << "  cerr << \"Cannot yet select: \";\n";
+        if (OpName != "ISD::INTRINSIC_W_CHAIN" &&
+            OpName != "ISD::INTRINSIC_WO_CHAIN" &&
+            OpName != "ISD::INTRINSIC_VOID") {
+          OS << "  N.Val->dump(CurDAG);\n";
+        } else {
+          OS << "  unsigned iid = cast<ConstantSDNode>(N.getOperand("
+            "N.getOperand(0).getValueType() == MVT::Other))->getValue();\n"
+             << "  cerr << \"intrinsic %\"<< "
+            "Intrinsic::getName((Intrinsic::ID)iid);\n";
+        }
+        OS << "  cerr << '\\n';\n"
+           << "  abort();\n"
+           << "  return NULL;\n";
+      }
+      OS << "}\n\n";
+    }
+  }
+  
+  // Emit boilerplate.
+  OS << "SDNode *Select_INLINEASM(SDOperand N) {\n"
+     << "  std::vector<SDOperand> Ops(N.Val->op_begin(), N.Val->op_end());\n"
+     << "  SelectInlineAsmMemoryOperands(Ops, *CurDAG);\n\n"
+    
+     << "  // Ensure that the asm operands are themselves selected.\n"
+     << "  for (unsigned j = 0, e = Ops.size(); j != e; ++j)\n"
+     << "    AddToISelQueue(Ops[j]);\n\n"
+    
+     << "  std::vector<MVT::ValueType> VTs;\n"
+     << "  VTs.push_back(MVT::Other);\n"
+     << "  VTs.push_back(MVT::Flag);\n"
+     << "  SDOperand New = CurDAG->getNode(ISD::INLINEASM, VTs, &Ops[0], "
+                 "Ops.size());\n"
+     << "  return New.Val;\n"
+     << "}\n\n";
+  
+  OS << "SDNode *Select_LABEL(const SDOperand &N) {\n"
+     << "  SDOperand Chain = N.getOperand(0);\n"
+     << "  SDOperand N1 = N.getOperand(1);\n"
+     << "  unsigned C = cast<ConstantSDNode>(N1)->getValue();\n"
+     << "  SDOperand Tmp = CurDAG->getTargetConstant(C, MVT::i32);\n"
+     << "  AddToISelQueue(Chain);\n"
+     << "  return CurDAG->getTargetNode(TargetInstrInfo::LABEL,\n"
+     << "                               MVT::Other, Tmp, Chain);\n"
+     << "}\n\n";
+
+  OS << "// The main instruction selector code.\n"
+     << "SDNode *SelectCode(SDOperand N) {\n"
+     << "  if (N.getOpcode() >= ISD::BUILTIN_OP_END &&\n"
+     << "      N.getOpcode() < (ISD::BUILTIN_OP_END+" << InstNS
+     << "INSTRUCTION_LIST_END)) {\n"
+     << "    return NULL;   // Already selected.\n"
+     << "  }\n\n"
+     << "  MVT::ValueType NVT = N.Val->getValueType(0);\n"
+     << "  switch (N.getOpcode()) {\n"
+     << "  default: break;\n"
+     << "  case ISD::EntryToken:       // These leaves remain the same.\n"
+     << "  case ISD::BasicBlock:\n"
+     << "  case ISD::Register:\n"
+     << "  case ISD::HANDLENODE:\n"
+     << "  case ISD::TargetConstant:\n"
+     << "  case ISD::TargetConstantPool:\n"
+     << "  case ISD::TargetFrameIndex:\n"
+     << "  case ISD::TargetExternalSymbol:\n"
+     << "  case ISD::TargetJumpTable:\n"
+     << "  case ISD::TargetGlobalTLSAddress:\n"
+     << "  case ISD::TargetGlobalAddress: {\n"
+     << "    return NULL;\n"
+     << "  }\n"
+     << "  case ISD::AssertSext:\n"
+     << "  case ISD::AssertZext: {\n"
+     << "    AddToISelQueue(N.getOperand(0));\n"
+     << "    ReplaceUses(N, N.getOperand(0));\n"
+     << "    return NULL;\n"
+     << "  }\n"
+     << "  case ISD::TokenFactor:\n"
+     << "  case ISD::CopyFromReg:\n"
+     << "  case ISD::CopyToReg: {\n"
+     << "    for (unsigned i = 0, e = N.getNumOperands(); i != e; ++i)\n"
+     << "      AddToISelQueue(N.getOperand(i));\n"
+     << "    return NULL;\n"
+     << "  }\n"
+     << "  case ISD::INLINEASM: return Select_INLINEASM(N);\n"
+     << "  case ISD::LABEL: return Select_LABEL(N);\n";
+
+    
+  // Loop over all of the case statements, emiting a call to each method we
+  // emitted above.
+  for (std::map<std::string, std::vector<PatternToMatch*> >::iterator
+         PBOI = PatternsByOpcode.begin(), E = PatternsByOpcode.end();
+       PBOI != E; ++PBOI) {
+    const std::string &OpName = PBOI->first;
+    // Potentially multiple versions of select for this opcode. One for each
+    // ValueType of the node (or its first true operand if it doesn't produce a
+    // result.
+    std::map<std::string, std::vector<std::string> >::iterator OpVTI =
+      OpcodeVTMap.find(OpName);
+    std::vector<std::string> &OpVTs = OpVTI->second;
+    OS << "  case " << OpName << ": {\n";
+    if (OpVTs.size() == 1) {
+      std::string &VTStr = OpVTs[0];
+      OS << "    return Select_" << getLegalCName(OpName)
+         << VTStr << "(N);\n";
+    } else {
+      // Keep track of whether we see a pattern that has an iPtr result.
+      bool HasPtrPattern = false;
+      bool HasDefaultPattern = false;
+      
+      OS << "    switch (NVT) {\n";
+      for (unsigned i = 0, e = OpVTs.size(); i < e; ++i) {
+        std::string &VTStr = OpVTs[i];
+        if (VTStr.empty()) {
+          HasDefaultPattern = true;
+          continue;
+        }
+
+        // If this is a match on iPTR: don't emit it directly, we need special
+        // code.
+        if (VTStr == "_iPTR") {
+          HasPtrPattern = true;
+          continue;
+        }
+        OS << "    case MVT::" << VTStr.substr(1) << ":\n"
+           << "      return Select_" << getLegalCName(OpName)
+           << VTStr << "(N);\n";
+      }
+      OS << "    default:\n";
+      
+      // If there is an iPTR result version of this pattern, emit it here.
+      if (HasPtrPattern) {
+        OS << "      if (NVT == TLI.getPointerTy())\n";
+        OS << "        return Select_" << getLegalCName(OpName) <<"_iPTR(N);\n";
+      }
+      if (HasDefaultPattern) {
+        OS << "      return Select_" << getLegalCName(OpName) << "(N);\n";
+      }
+      OS << "      break;\n";
+      OS << "    }\n";
+      OS << "    break;\n";
+    }
+    OS << "  }\n";
+  }
+
+  OS << "  } // end of big switch.\n\n"
+     << "  cerr << \"Cannot yet select: \";\n"
+     << "  if (N.getOpcode() != ISD::INTRINSIC_W_CHAIN &&\n"
+     << "      N.getOpcode() != ISD::INTRINSIC_WO_CHAIN &&\n"
+     << "      N.getOpcode() != ISD::INTRINSIC_VOID) {\n"
+     << "    N.Val->dump(CurDAG);\n"
+     << "  } else {\n"
+     << "    unsigned iid = cast<ConstantSDNode>(N.getOperand("
+               "N.getOperand(0).getValueType() == MVT::Other))->getValue();\n"
+     << "    cerr << \"intrinsic %\"<< "
+               "Intrinsic::getName((Intrinsic::ID)iid);\n"
+     << "  }\n"
+     << "  cerr << '\\n';\n"
+     << "  abort();\n"
+     << "  return NULL;\n"
+     << "}\n";
+}
+
+void DAGISelEmitter::run(std::ostream &OS) {
+  EmitSourceFileHeader("DAG Instruction Selector for the " + Target.getName() +
+                       " target", OS);
+  
+  OS << "// *** NOTE: This file is #included into the middle of the target\n"
+     << "// *** instruction selector class.  These functions are really "
+     << "methods.\n\n";
+  
+  OS << "#include \"llvm/Support/Compiler.h\"\n";
+
+  OS << "// Instruction selector priority queue:\n"
+     << "std::vector<SDNode*> ISelQueue;\n";
+  OS << "/// Keep track of nodes which have already been added to queue.\n"
+     << "unsigned char *ISelQueued;\n";
+  OS << "/// Keep track of nodes which have already been selected.\n"
+     << "unsigned char *ISelSelected;\n";
+  OS << "/// Dummy parameter to ReplaceAllUsesOfValueWith().\n"
+     << "std::vector<SDNode*> ISelKilled;\n\n";
+
+  OS << "/// IsChainCompatible - Returns true if Chain is Op or Chain does\n";
+  OS << "/// not reach Op.\n";
+  OS << "static bool IsChainCompatible(SDNode *Chain, SDNode *Op) {\n";
+  OS << "  if (Chain->getOpcode() == ISD::EntryToken)\n";
+  OS << "    return true;\n";
+  OS << "  else if (Chain->getOpcode() == ISD::TokenFactor)\n";
+  OS << "    return false;\n";
+  OS << "  else if (Chain->getNumOperands() > 0) {\n";
+  OS << "    SDOperand C0 = Chain->getOperand(0);\n";
+  OS << "    if (C0.getValueType() == MVT::Other)\n";
+  OS << "      return C0.Val != Op && IsChainCompatible(C0.Val, Op);\n";
+  OS << "  }\n";
+  OS << "  return true;\n";
+  OS << "}\n";
+
+  OS << "/// Sorting functions for the selection queue.\n"
+     << "struct isel_sort : public std::binary_function"
+     << "<SDNode*, SDNode*, bool> {\n"
+     << "  bool operator()(const SDNode* left, const SDNode* right) "
+     << "const {\n"
+     << "    return (left->getNodeId() > right->getNodeId());\n"
+     << "  }\n"
+     << "};\n\n";
+
+  OS << "inline void setQueued(int Id) {\n";
+  OS << "  ISelQueued[Id / 8] |= 1 << (Id % 8);\n";
+  OS << "}\n";
+  OS << "inline bool isQueued(int Id) {\n";
+  OS << "  return ISelQueued[Id / 8] & (1 << (Id % 8));\n";
+  OS << "}\n";
+  OS << "inline void setSelected(int Id) {\n";
+  OS << "  ISelSelected[Id / 8] |= 1 << (Id % 8);\n";
+  OS << "}\n";
+  OS << "inline bool isSelected(int Id) {\n";
+  OS << "  return ISelSelected[Id / 8] & (1 << (Id % 8));\n";
+  OS << "}\n\n";
+
+  OS << "void AddToISelQueue(SDOperand N) DISABLE_INLINE {\n";
+  OS << "  int Id = N.Val->getNodeId();\n";
+  OS << "  if (Id != -1 && !isQueued(Id)) {\n";
+  OS << "    ISelQueue.push_back(N.Val);\n";
+ OS << "    std::push_heap(ISelQueue.begin(), ISelQueue.end(), isel_sort());\n";
+  OS << "    setQueued(Id);\n";
+  OS << "  }\n";
+  OS << "}\n\n";
+
+  OS << "inline void RemoveKilled() {\n";
+OS << "  unsigned NumKilled = ISelKilled.size();\n";
+  OS << "  if (NumKilled) {\n";
+  OS << "    for (unsigned i = 0; i != NumKilled; ++i) {\n";
+  OS << "      SDNode *Temp = ISelKilled[i];\n";
+  OS << "      ISelQueue.erase(std::remove(ISelQueue.begin(), ISelQueue.end(), "
+     << "Temp), ISelQueue.end());\n";
+  OS << "    };\n";
+ OS << "    std::make_heap(ISelQueue.begin(), ISelQueue.end(), isel_sort());\n";
+  OS << "    ISelKilled.clear();\n";
+  OS << "  }\n";
+  OS << "}\n\n";
+
+  OS << "void ReplaceUses(SDOperand F, SDOperand T) DISABLE_INLINE {\n";
+  OS << "  CurDAG->ReplaceAllUsesOfValueWith(F, T, ISelKilled);\n";
+  OS << "  setSelected(F.Val->getNodeId());\n";
+  OS << "  RemoveKilled();\n";
+  OS << "}\n";
+  OS << "inline void ReplaceUses(SDNode *F, SDNode *T) {\n";
+  OS << "  CurDAG->ReplaceAllUsesWith(F, T, &ISelKilled);\n";
+  OS << "  setSelected(F->getNodeId());\n";
+  OS << "  RemoveKilled();\n";
+  OS << "}\n\n";
+
+  OS << "// SelectRoot - Top level entry to DAG isel.\n";
+  OS << "SDOperand SelectRoot(SDOperand Root) {\n";
+  OS << "  SelectRootInit();\n";
+  OS << "  unsigned NumBytes = (DAGSize + 7) / 8;\n";
+  OS << "  ISelQueued   = new unsigned char[NumBytes];\n";
+  OS << "  ISelSelected = new unsigned char[NumBytes];\n";
+  OS << "  memset(ISelQueued,   0, NumBytes);\n";
+  OS << "  memset(ISelSelected, 0, NumBytes);\n";
+  OS << "\n";
+  OS << "  // Create a dummy node (which is not added to allnodes), that adds\n"
+     << "  // a reference to the root node, preventing it from being deleted,\n"
+     << "  // and tracking any changes of the root.\n"
+     << "  HandleSDNode Dummy(CurDAG->getRoot());\n"
+     << "  ISelQueue.push_back(CurDAG->getRoot().Val);\n";
+  OS << "  while (!ISelQueue.empty()) {\n";
+  OS << "    SDNode *Node = ISelQueue.front();\n";
+  OS << "    std::pop_heap(ISelQueue.begin(), ISelQueue.end(), isel_sort());\n";
+  OS << "    ISelQueue.pop_back();\n";
+  OS << "    if (!isSelected(Node->getNodeId())) {\n";
+  OS << "      SDNode *ResNode = Select(SDOperand(Node, 0));\n";
+  OS << "      if (ResNode != Node) {\n";
+  OS << "        if (ResNode)\n";
+  OS << "          ReplaceUses(Node, ResNode);\n";
+  OS << "        if (Node->use_empty()) { // Don't delete EntryToken, etc.\n";
+  OS << "          CurDAG->RemoveDeadNode(Node, ISelKilled);\n";
+  OS << "          RemoveKilled();\n";
+  OS << "        }\n";
+  OS << "      }\n";
+  OS << "    }\n";
+  OS << "  }\n";
+  OS << "\n";
+  OS << "  delete[] ISelQueued;\n";
+  OS << "  ISelQueued = NULL;\n";
+  OS << "  delete[] ISelSelected;\n";
+  OS << "  ISelSelected = NULL;\n";
+  OS << "  return Dummy.getValue();\n";
+  OS << "}\n";
+  
+  Intrinsics = LoadIntrinsics(Records);
+  ParseNodeInfo();
+  ParseNodeTransforms(OS);
+  ParseComplexPatterns();
+  ParsePatternFragments(OS);
+  ParseDefaultOperands();
+  ParseInstructions();
+  ParsePatterns();
+  
+  // Generate variants.  For example, commutative patterns can match
+  // multiple ways.  Add them to PatternsToMatch as well.
+  GenerateVariants();
+
+  DOUT << "\n\nALL PATTERNS TO MATCH:\n\n";
+  for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i) {
+    DOUT << "PATTERN: ";   DEBUG(PatternsToMatch[i].getSrcPattern()->dump());
+    DOUT << "\nRESULT:  "; DEBUG(PatternsToMatch[i].getDstPattern()->dump());
+    DOUT << "\n";
+  }
+  
+  // At this point, we have full information about the 'Patterns' we need to
+  // parse, both implicitly from instructions as well as from explicit pattern
+  // definitions.  Emit the resultant instruction selector.
+  EmitInstructionSelector(OS);  
+  
+  for (std::map<Record*, TreePattern*>::iterator I = PatternFragments.begin(),
+       E = PatternFragments.end(); I != E; ++I)
+    delete I->second;
+  PatternFragments.clear();
+
+  Instructions.clear();
+}