[TableGen] Avoid leaking TreePatternNodes by using shared_ptr.

By using std::shared_ptr for TreePatternNode, we can avoid leaking them.

Reviewers: craig.topper, dsanders, stoklund, tstellar, zturner

Reviewed By: dsanders

Differential Revision: https://reviews.llvm.org/D47463

llvm-svn: 333591

1 files changed, 165 insertions, 172 deletions

diff --git a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
index 875e6baff4a..730d336ce94 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -1564,7 +1564,7 @@ bool TreePatternNode::hasProperTypeByHwMode() const {
   for (const TypeSetByHwMode &S : Types)
     if (!S.isDefaultOnly())
       return true;
-  for (TreePatternNode *C : Children)
+  for (const TreePatternNodePtr &C : Children)
     if (C->hasProperTypeByHwMode())
       return true;
   return false;
@@ -1574,7 +1574,7 @@ bool TreePatternNode::hasPossibleType() const {
   for (const TypeSetByHwMode &S : Types)
     if (!S.isPossible())
       return false;
-  for (TreePatternNode *C : Children)
+  for (const TreePatternNodePtr &C : Children)
     if (!C->hasPossibleType())
       return false;
   return true;
@@ -1587,7 +1587,7 @@ bool TreePatternNode::setDefaultMode(unsigned Mode) {
     if (S.get(DefaultMode).empty())
       return false;
   }
-  for (TreePatternNode *C : Children)
+  for (const TreePatternNodePtr &C : Children)
     if (!C->setDefaultMode(Mode))
       return false;
   return true;
@@ -1644,13 +1644,6 @@ MVT::SimpleValueType SDNodeInfo::getKnownType(unsigned ResNo) const {
 // TreePatternNode implementation
 //
 
-TreePatternNode::~TreePatternNode() {
-#if 0 // FIXME: implement refcounted tree nodes!
-  for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
-    delete getChild(i);
-#endif
-}
-
 static unsigned GetNumNodeResults(Record *Operator, CodeGenDAGPatterns &CDP) {
   if (Operator->getName() == "set" ||
       Operator->getName() == "implicit")
@@ -1783,16 +1776,17 @@ bool TreePatternNode::isIsomorphicTo(const TreePatternNode *N,
 
 /// clone - Make a copy of this tree and all of its children.
 ///
-TreePatternNode *TreePatternNode::clone() const {
-  TreePatternNode *New;
+TreePatternNodePtr TreePatternNode::clone() const {
+  TreePatternNodePtr New;
   if (isLeaf()) {
-    New = new TreePatternNode(getLeafValue(), getNumTypes());
+    New = std::make_shared<TreePatternNode>(getLeafValue(), getNumTypes());
   } else {
-    std::vector<TreePatternNode*> CChildren;
+    std::vector<TreePatternNodePtr> 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, getNumTypes());
+    New = std::make_shared<TreePatternNode>(getOperator(), CChildren,
+                                            getNumTypes());
   }
   New->setName(getName());
   New->Types = Types;
@@ -1813,8 +1807,8 @@ void TreePatternNode::RemoveAllTypes() {
 
 /// SubstituteFormalArguments - Replace the formal arguments in this tree
 /// with actual values specified by ArgMap.
-void TreePatternNode::
-SubstituteFormalArguments(std::map<std::string, TreePatternNode*> &ArgMap) {
+void TreePatternNode::SubstituteFormalArguments(
+    std::map<std::string, TreePatternNodePtr> &ArgMap) {
   if (isLeaf()) return;
 
   for (unsigned i = 0, e = getNumChildren(); i != e; ++i) {
@@ -1826,7 +1820,7 @@ SubstituteFormalArguments(std::map<std::string, TreePatternNode*> &ArgMap) {
       if (isa<UnsetInit>(Val) || (isa<DefInit>(Val) &&
           cast<DefInit>(Val)->getDef()->getName() == "node")) {
         // We found a use of a formal argument, replace it with its value.
-        TreePatternNode *NewChild = ArgMap[Child->getName()];
+        TreePatternNodePtr NewChild = ArgMap[Child->getName()];
         assert(NewChild && "Couldn't find formal argument!");
         assert((Child->getPredicateFns().empty() ||
                 NewChild->getPredicateFns() == Child->getPredicateFns()) &&
@@ -1843,19 +1837,20 @@ SubstituteFormalArguments(std::map<std::string, TreePatternNode*> &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) {
+TreePatternNodePtr TreePatternNode::InlinePatternFragments(TreePatternNodePtr T,
+                                                           TreePattern &TP) {
   if (TP.hasError())
     return nullptr;
 
   if (isLeaf())
-     return this;  // nothing to do.
+    return T; // nothing to do.
   Record *Op = getOperator();
 
   if (!Op->isSubClassOf("PatFrag")) {
     // Just recursively inline children nodes.
     for (unsigned i = 0, e = getNumChildren(); i != e; ++i) {
-      TreePatternNode *Child = getChild(i);
-      TreePatternNode *NewChild = Child->InlinePatternFragments(TP);
+      TreePatternNodePtr Child = getChildShared(i);
+      TreePatternNodePtr NewChild = Child->InlinePatternFragments(Child, TP);
 
       assert((Child->getPredicateFns().empty() ||
               NewChild->getPredicateFns() == Child->getPredicateFns()) &&
@@ -1863,7 +1858,7 @@ TreePatternNode *TreePatternNode::InlinePatternFragments(TreePattern &TP) {
 
       setChild(i, NewChild);
     }
-    return this;
+    return T;
   }
 
   // Otherwise, we found a reference to a fragment.  First, look up its
@@ -1874,10 +1869,10 @@ TreePatternNode *TreePatternNode::InlinePatternFragments(TreePattern &TP) {
   if (Frag->getNumArgs() != Children.size()) {
     TP.error("'" + Op->getName() + "' fragment requires " +
              Twine(Frag->getNumArgs()) + " operands!");
-    return nullptr;
+    return {nullptr};
   }
 
-  TreePatternNode *FragTree = Frag->getOnlyTree()->clone();
+  TreePatternNodePtr FragTree = Frag->getOnlyTree()->clone();
 
   TreePredicateFn PredFn(Frag);
   if (!PredFn.isAlwaysTrue())
@@ -1886,9 +1881,11 @@ TreePatternNode *TreePatternNode::InlinePatternFragments(TreePattern &TP) {
   // 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);
+    std::map<std::string, TreePatternNodePtr> ArgMap;
+    for (unsigned i = 0, e = Frag->getNumArgs(); i != e; ++i) {
+      TreePatternNodePtr Child = getChildShared(i);
+      ArgMap[Frag->getArgName(i)] = Child->InlinePatternFragments(Child, TP);
+    }
 
     FragTree->SubstituteFormalArguments(ArgMap);
   }
@@ -1901,12 +1898,9 @@ TreePatternNode *TreePatternNode::InlinePatternFragments(TreePattern &TP) {
   for (const TreePredicateFn &Pred : getPredicateFns())
     FragTree->addPredicateFn(Pred);
 
-  // Get a new copy of this fragment to stitch into here.
-  //delete this;    // FIXME: implement refcounting!
-
   // The fragment we inlined could have recursive inlining that is needed.  See
   // if there are any pattern fragments in it and inline them as needed.
-  return FragTree->InlinePatternFragments(TP);
+  return FragTree->InlinePatternFragments(FragTree, TP);
 }
 
 /// getImplicitType - Check to see if the specified record has an implicit
@@ -2508,10 +2502,10 @@ TreePattern::TreePattern(Record *TheRec, DagInit *Pat, bool isInput,
   Trees.push_back(ParseTreePattern(Pat, ""));
 }
 
-TreePattern::TreePattern(Record *TheRec, TreePatternNode *Pat, bool isInput,
-                         CodeGenDAGPatterns &cdp) : TheRecord(TheRec), CDP(cdp),
-                         isInputPattern(isInput), HasError(false),
-                         Infer(*this) {
+TreePattern::TreePattern(Record *TheRec, TreePatternNodePtr Pat, bool isInput,
+                         CodeGenDAGPatterns &cdp)
+    : TheRecord(TheRec), CDP(cdp), isInputPattern(isInput), HasError(false),
+      Infer(*this) {
   Trees.push_back(Pat);
 }
 
@@ -2524,8 +2518,8 @@ void TreePattern::error(const Twine &Msg) {
 }
 
 void TreePattern::ComputeNamedNodes() {
-  for (TreePatternNode *Tree : Trees)
-    ComputeNamedNodes(Tree);
+  for (TreePatternNodePtr &Tree : Trees)
+    ComputeNamedNodes(Tree.get());
 }
 
 void TreePattern::ComputeNamedNodes(TreePatternNode *N) {
@@ -2536,8 +2530,8 @@ void TreePattern::ComputeNamedNodes(TreePatternNode *N) {
     ComputeNamedNodes(N->getChild(i));
 }
 
-
-TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
+TreePatternNodePtr TreePattern::ParseTreePattern(Init *TheInit,
+                                                 StringRef OpName) {
   if (DefInit *DI = dyn_cast<DefInit>(TheInit)) {
     Record *R = DI->getDef();
 
@@ -2551,7 +2545,7 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
         OpName);
 
     // Input argument?
-    TreePatternNode *Res = new TreePatternNode(DI, 1);
+    TreePatternNodePtr Res = std::make_shared<TreePatternNode>(DI, 1);
     if (R->getName() == "node" && !OpName.empty()) {
       if (OpName.empty())
         error("'node' argument requires a name to match with operand list");
@@ -2566,7 +2560,7 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
   if (isa<UnsetInit>(TheInit)) {
     if (OpName.empty())
       error("'?' argument requires a name to match with operand list");
-    TreePatternNode *Res = new TreePatternNode(TheInit, 1);
+    TreePatternNodePtr Res = std::make_shared<TreePatternNode>(TheInit, 1);
     Args.push_back(OpName);
     Res->setName(OpName);
     return Res;
@@ -2575,7 +2569,7 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
   if (IntInit *II = dyn_cast<IntInit>(TheInit)) {
     if (!OpName.empty())
       error("Constant int argument should not have a name!");
-    return new TreePatternNode(II, 1);
+    return std::make_shared<TreePatternNode>(II, 1);
   }
 
   if (BitsInit *BI = dyn_cast<BitsInit>(TheInit)) {
@@ -2601,8 +2595,8 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
     if (Dag->getNumArgs() != 1)
       error("Type cast only takes one operand!");
 
-    TreePatternNode *New = ParseTreePattern(Dag->getArg(0),
-                                            Dag->getArgNameStr(0));
+    TreePatternNodePtr New =
+        ParseTreePattern(Dag->getArg(0), Dag->getArgNameStr(0));
 
     // Apply the type cast.
     assert(New->getNumTypes() == 1 && "FIXME: Unhandled");
@@ -2650,7 +2644,7 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
       error("Cannot use '" + Operator->getName() + "' in an output pattern!");
   }
 
-  std::vector<TreePatternNode*> Children;
+  std::vector<TreePatternNodePtr> Children;
 
   // Parse all the operands.
   for (unsigned i = 0, e = Dag->getNumArgs(); i != e; ++i)
@@ -2677,13 +2671,14 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
     else // Otherwise, no chain.
       Operator = getDAGPatterns().get_intrinsic_wo_chain_sdnode();
 
-    TreePatternNode *IIDNode = new TreePatternNode(IntInit::get(IID), 1);
+    TreePatternNodePtr IIDNode =
+        std::make_shared<TreePatternNode>(IntInit::get(IID), 1);
     Children.insert(Children.begin(), IIDNode);
   }
 
   if (Operator->isSubClassOf("ComplexPattern")) {
     for (unsigned i = 0; i < Children.size(); ++i) {
-      TreePatternNode *Child = Children[i];
+      TreePatternNodePtr Child = Children[i];
 
       if (Child->getName().empty())
         error("All arguments to a ComplexPattern must be named");
@@ -2702,7 +2697,8 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
     }
   }
 
-  TreePatternNode *Result = new TreePatternNode(Operator, Children, NumResults);
+  TreePatternNodePtr Result =
+      std::make_shared<TreePatternNode>(Operator, Children, NumResults);
   Result->setName(OpName);
 
   if (Dag->getName()) {
@@ -2718,7 +2714,7 @@ TreePatternNode *TreePattern::ParseTreePattern(Init *TheInit, StringRef OpName){
 /// more type generic things and have useless type casts fold away.
 ///
 /// This returns true if any change is made.
-static bool SimplifyTree(TreePatternNode *&N) {
+static bool SimplifyTree(TreePatternNodePtr &N) {
   if (N->isLeaf())
     return false;
 
@@ -2728,7 +2724,7 @@ static bool SimplifyTree(TreePatternNode *&N) {
       N->getExtType(0).isValueTypeByHwMode(false) &&
       N->getExtType(0) == N->getChild(0)->getExtType(0) &&
       N->getName().empty()) {
-    N = N->getChild(0);
+    N = N->getChildShared(0);
     SimplifyTree(N);
     return true;
   }
@@ -2736,7 +2732,7 @@ static bool SimplifyTree(TreePatternNode *&N) {
   // Walk all children.
   bool MadeChange = false;
   for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i) {
-    TreePatternNode *Child = N->getChild(i);
+    TreePatternNodePtr Child = N->getChildShared(i);
     MadeChange |= SimplifyTree(Child);
     N->setChild(i, Child);
   }
@@ -2756,7 +2752,7 @@ InferAllTypes(const StringMap<SmallVector<TreePatternNode*,1> > *InNamedTypes) {
   bool MadeChange = true;
   while (MadeChange) {
     MadeChange = false;
-    for (TreePatternNode *&Tree : Trees) {
+    for (TreePatternNodePtr &Tree : Trees) {
       MadeChange |= Tree->ApplyTypeConstraints(*this, false);
       MadeChange |= SimplifyTree(Tree);
     }
@@ -2784,7 +2780,7 @@ InferAllTypes(const StringMap<SmallVector<TreePatternNode*,1> > *InNamedTypes) {
           // changing the type of the input register in this case.  This allows
           // us to match things like:
           //  def : Pat<(v1i64 (bitconvert(v2i32 DPR:$src))), (v1i64 DPR:$src)>;
-          if (Node == Trees[0] && Node->isLeaf()) {
+          if (Node == Trees[0].get() && Node->isLeaf()) {
             DefInit *DI = dyn_cast<DefInit>(Node->getLeafValue());
             if (DI && (DI->getDef()->isSubClassOf("RegisterClass") ||
                        DI->getDef()->isSubClassOf("RegisterOperand")))
@@ -2815,7 +2811,7 @@ InferAllTypes(const StringMap<SmallVector<TreePatternNode*,1> > *InNamedTypes) {
   }
 
   bool HasUnresolvedTypes = false;
-  for (const TreePatternNode *Tree : Trees)
+  for (const TreePatternNodePtr &Tree : Trees)
     HasUnresolvedTypes |= Tree->ContainsUnresolvedType(*this);
   return !HasUnresolvedTypes;
 }
@@ -2832,7 +2828,7 @@ void TreePattern::print(raw_ostream &OS) const {
 
   if (Trees.size() > 1)
     OS << "[\n";
-  for (const TreePatternNode *Tree : Trees) {
+  for (const TreePatternNodePtr &Tree : Trees) {
     OS << "\t";
     Tree->print(OS);
     OS << "\n";
@@ -3048,9 +3044,9 @@ void CodeGenDAGPatterns::ParseDefaultOperands() {
     // Copy the operands over into a DAGDefaultOperand.
     DAGDefaultOperand DefaultOpInfo;
 
-    TreePatternNode *T = P.getTree(0);
+    const TreePatternNodePtr &T = P.getTree(0);
     for (unsigned op = 0, e = T->getNumChildren(); op != e; ++op) {
-      TreePatternNode *TPN = T->getChild(op);
+      TreePatternNodePtr TPN = T->getChildShared(op);
       while (TPN->ApplyTypeConstraints(P, false))
         /* Resolve all types */;
 
@@ -3069,8 +3065,8 @@ void CodeGenDAGPatterns::ParseDefaultOperands() {
 
 /// 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) {
+static bool HandleUse(TreePattern *I, TreePatternNodePtr Pat,
+                      std::map<std::string, TreePatternNodePtr> &InstInputs) {
   // No name -> not interesting.
   if (Pat->getName().empty()) {
     if (Pat->isLeaf()) {
@@ -3095,7 +3091,7 @@ static bool HandleUse(TreePattern *I, TreePatternNode *Pat,
   if (Rec->getName() == "srcvalue")
     return false;
 
-  TreePatternNode *&Slot = InstInputs[Pat->getName()];
+  TreePatternNodePtr &Slot = InstInputs[Pat->getName()];
   if (!Slot) {
     Slot = Pat;
     return true;
@@ -3119,11 +3115,11 @@ static bool HandleUse(TreePattern *I, TreePatternNode *Pat,
 /// 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 CodeGenDAGPatterns::
-FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
-                            std::map<std::string, TreePatternNode*> &InstInputs,
-                            std::map<std::string, TreePatternNode*>&InstResults,
-                            std::vector<Record*> &InstImpResults) {
+void CodeGenDAGPatterns::FindPatternInputsAndOutputs(
+    TreePattern *I, TreePatternNodePtr Pat,
+    std::map<std::string, TreePatternNodePtr> &InstInputs,
+    std::map<std::string, TreePatternNodePtr> &InstResults,
+    std::vector<Record *> &InstImpResults) {
   if (Pat->isLeaf()) {
     bool isUse = HandleUse(I, Pat, InstInputs);
     if (!isUse && Pat->getTransformFn())
@@ -3151,8 +3147,8 @@ FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
     for (unsigned i = 0, e = Pat->getNumChildren(); i != e; ++i) {
       if (Pat->getChild(i)->getNumTypes() == 0)
         I->error("Cannot have void nodes inside of patterns!");
-      FindPatternInputsAndOutputs(I, Pat->getChild(i), InstInputs, InstResults,
-                                  InstImpResults);
+      FindPatternInputsAndOutputs(I, Pat->getChildShared(i), InstInputs,
+                                  InstResults, InstImpResults);
     }
 
     // If this is a non-leaf node with no children, treat it basically as if
@@ -3174,7 +3170,7 @@ FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
   // Check the set destinations.
   unsigned NumDests = Pat->getNumChildren()-1;
   for (unsigned i = 0; i != NumDests; ++i) {
-    TreePatternNode *Dest = Pat->getChild(i);
+    TreePatternNodePtr Dest = Pat->getChildShared(i);
     if (!Dest->isLeaf())
       I->error("set destination should be a register!");
 
@@ -3201,8 +3197,8 @@ FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
   }
 
   // Verify and collect info from the computation.
-  FindPatternInputsAndOutputs(I, Pat->getChild(NumDests),
-                              InstInputs, InstResults, InstImpResults);
+  FindPatternInputsAndOutputs(I, Pat->getChildShared(NumDests), InstInputs,
+                              InstResults, InstImpResults);
 }
 
 //===----------------------------------------------------------------------===//
@@ -3224,7 +3220,7 @@ public:
 
   void Analyze(const TreePattern *Pat) {
     // Assume only the first tree is the pattern. The others are clobber nodes.
-    AnalyzeNode(Pat->getTree(0));
+    AnalyzeNode(Pat->getTree(0).get());
   }
 
   void Analyze(const PatternToMatch &Pat) {
@@ -3436,11 +3432,11 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
 
   // 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;
+  std::map<std::string, TreePatternNodePtr> 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::map<std::string, TreePatternNodePtr> InstResults;
 
   std::vector<Record*> InstImpResults;
 
@@ -3449,7 +3445,7 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
   SmallString<32> TypesString;
   for (unsigned j = 0, e = I->getNumTrees(); j != e; ++j) {
     TypesString.clear();
-    TreePatternNode *Pat = I->getTree(j);
+    TreePatternNodePtr Pat = I->getTree(j);
     if (Pat->getNumTypes() != 0) {
       raw_svector_ostream OS(TypesString);
       for (unsigned k = 0, ke = Pat->getNumTypes(); k != ke; ++k) {
@@ -3477,7 +3473,7 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
 
   // Check that all of the results occur first in the list.
   std::vector<Record*> Results;
-  SmallVector<TreePatternNode *, 2> ResNodes;
+  SmallVector<TreePatternNodePtr, 2> ResNodes;
   for (unsigned i = 0; i != NumResults; ++i) {
     if (i == CGI.Operands.size())
       I->error("'" + InstResults.begin()->first +
@@ -3485,7 +3481,7 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
     const std::string &OpName = CGI.Operands[i].Name;
 
     // Check that it exists in InstResults.
-    TreePatternNode *RNode = InstResults[OpName];
+    TreePatternNodePtr RNode = InstResults[OpName];
     if (!RNode)
       I->error("Operand $" + OpName + " does not exist in operand list!");
 
@@ -3508,9 +3504,9 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
 
   // 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::map<std::string, TreePatternNodePtr> InstInputsCheck(InstInputs);
 
-  std::vector<TreePatternNode*> ResultNodeOperands;
+  std::vector<TreePatternNodePtr> ResultNodeOperands;
   std::vector<Record*> Operands;
   for (unsigned i = NumResults, e = CGI.Operands.size(); i != e; ++i) {
     CGIOperandList::OperandInfo &Op = CGI.Operands[i];
@@ -3530,7 +3526,7 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
       I->error("Operand $" + OpName +
                " does not appear in the instruction pattern");
     }
-    TreePatternNode *InVal = InstInputsCheck[OpName];
+    TreePatternNodePtr InVal = InstInputsCheck[OpName];
     InstInputsCheck.erase(OpName);   // It occurred, remove from map.
 
     if (InVal->isLeaf() && isa<DefInit>(InVal->getLeafValue())) {
@@ -3542,7 +3538,7 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
     Operands.push_back(Op.Rec);
 
     // Construct the result for the dest-pattern operand list.
-    TreePatternNode *OpNode = InVal->clone();
+    TreePatternNodePtr OpNode = InVal->clone();
 
     // No predicate is useful on the result.
     OpNode->clearPredicateFns();
@@ -3550,9 +3546,10 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
     // Promote the xform function to be an explicit node if set.
     if (Record *Xform = OpNode->getTransformFn()) {
       OpNode->setTransformFn(nullptr);
-      std::vector<TreePatternNode*> Children;
+      std::vector<TreePatternNodePtr> Children;
       Children.push_back(OpNode);
-      OpNode = new TreePatternNode(Xform, Children, OpNode->getNumTypes());
+      OpNode = std::make_shared<TreePatternNode>(Xform, Children,
+                                                 OpNode->getNumTypes());
     }
 
     ResultNodeOperands.push_back(OpNode);
@@ -3562,9 +3559,9 @@ const DAGInstruction &CodeGenDAGPatterns::parseInstructionPattern(
     I->error("Input operand $" + InstInputsCheck.begin()->first +
              " occurs in pattern but not in operands list!");
 
-  TreePatternNode *ResultPattern =
-    new TreePatternNode(I->getRecord(), ResultNodeOperands,
-                        GetNumNodeResults(I->getRecord(), *this));
+  TreePatternNodePtr ResultPattern = std::make_shared<TreePatternNode>(
+      I->getRecord(), ResultNodeOperands,
+      GetNumNodeResults(I->getRecord(), *this));
   // Copy fully inferred output node types to instruction result pattern.
   for (unsigned i = 0; i != NumResults; ++i) {
     assert(ResNodes[i]->getNumTypes() == 1 && "FIXME: Unhandled");
@@ -3646,8 +3643,8 @@ void CodeGenDAGPatterns::ParseInstructions() {
       PatternRewriter(I);
     // FIXME: Assume only the first tree is the pattern. The others are clobber
     // nodes.
-    TreePatternNode *Pattern = I->getTree(0);
-    TreePatternNode *SrcPattern;
+    TreePatternNodePtr Pattern = I->getTree(0);
+    TreePatternNodePtr SrcPattern;
     if (Pattern->getOperator()->getName() == "set") {
       SrcPattern = Pattern->getChild(Pattern->getNumChildren()-1)->clone();
     } else{
@@ -3666,10 +3663,9 @@ void CodeGenDAGPatterns::ParseInstructions() {
   }
 }
 
+typedef std::pair<TreePatternNode *, unsigned> NameRecord;
 
-typedef std::pair<const TreePatternNode*, unsigned> NameRecord;
-
-static void FindNames(const TreePatternNode *P,
+static void FindNames(TreePatternNode *P,
                       std::map<std::string, NameRecord> &Names,
                       TreePattern *PatternTop) {
   if (!P->getName().empty()) {
@@ -3929,10 +3925,10 @@ void CodeGenDAGPatterns::ParsePatterns() {
     if (hasNullFragReference(Tree))
       continue;
 
-    TreePattern *Pattern = new TreePattern(CurPattern, Tree, true, *this);
+    TreePattern Pattern(CurPattern, Tree, true, *this);
 
     // Inline pattern fragments into it.
-    Pattern->InlinePatternFragments();
+    Pattern.InlinePatternFragments();
 
     ListInit *LI = CurPattern->getValueAsListInit("ResultInstrs");
     if (LI->empty()) continue;  // no pattern.
@@ -3953,12 +3949,12 @@ void CodeGenDAGPatterns::ParsePatterns() {
       // 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(&Pattern->getNamedNodesMap());
+          Pattern.InferAllTypes(&Pattern.getNamedNodesMap());
 
       // 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(&Pattern->getNamedNodesMap());
+          Result.InferAllTypes(&Pattern.getNamedNodesMap());
 
       IterateInference = false;
 
@@ -3967,12 +3963,12 @@ void CodeGenDAGPatterns::ParsePatterns() {
       // is considered resolved), but the result knows it needs to be 32- or
       // 64-bits.  Infer the other way for good measure.
       for (unsigned i = 0, e = std::min(Result.getTree(0)->getNumTypes(),
-                                        Pattern->getTree(0)->getNumTypes());
+                                        Pattern.getTree(0)->getNumTypes());
            i != e; ++i) {
-        IterateInference = Pattern->getTree(0)->UpdateNodeType(
+        IterateInference = Pattern.getTree(0)->UpdateNodeType(
             i, Result.getTree(0)->getExtType(i), Result);
         IterateInference |= Result.getTree(0)->UpdateNodeType(
-            i, Pattern->getTree(0)->getExtType(i), Result);
+            i, Pattern.getTree(0)->getExtType(i), Result);
       }
 
       // If our iteration has converged and the input pattern's types are fully
@@ -3987,45 +3983,45 @@ void CodeGenDAGPatterns::ParsePatterns() {
       if (!IterateInference && InferredAllPatternTypes &&
           !InferredAllResultTypes)
         IterateInference =
-            ForceArbitraryInstResultType(Result.getTree(0), Result);
+            ForceArbitraryInstResultType(Result.getTree(0).get(), 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!");
+      Pattern.error("Could not infer all types in pattern!");
     if (!InferredAllResultTypes) {
-      Pattern->dump();
+      Pattern.dump();
       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::map<std::string, TreePatternNodePtr> InstInputs;
+    std::map<std::string, TreePatternNodePtr> InstResults;
     std::vector<Record*> InstImpResults;
-    for (unsigned j = 0, ee = Pattern->getNumTrees(); j != ee; ++j)
-      FindPatternInputsAndOutputs(Pattern, Pattern->getTree(j),
-                                  InstInputs, InstResults,
-                                  InstImpResults);
+    for (unsigned j = 0, ee = Pattern.getNumTrees(); j != ee; ++j)
+      FindPatternInputsAndOutputs(&Pattern, Pattern.getTree(j), InstInputs,
+                                  InstResults, InstImpResults);
 
     // Promote the xform function to be an explicit node if set.
-    TreePatternNode *DstPattern = Result.getOnlyTree();
-    std::vector<TreePatternNode*> ResultNodeOperands;
+    TreePatternNodePtr DstPattern = Result.getOnlyTree();
+    std::vector<TreePatternNodePtr> ResultNodeOperands;
     for (unsigned ii = 0, ee = DstPattern->getNumChildren(); ii != ee; ++ii) {
-      TreePatternNode *OpNode = DstPattern->getChild(ii);
+      TreePatternNodePtr OpNode = DstPattern->getChildShared(ii);
       if (Record *Xform = OpNode->getTransformFn()) {
         OpNode->setTransformFn(nullptr);
-        std::vector<TreePatternNode*> Children;
+        std::vector<TreePatternNodePtr> Children;
         Children.push_back(OpNode);
-        OpNode = new TreePatternNode(Xform, Children, OpNode->getNumTypes());
+        OpNode = std::make_shared<TreePatternNode>(Xform, Children,
+                                                   OpNode->getNumTypes());
       }
       ResultNodeOperands.push_back(OpNode);
     }
     DstPattern = Result.getOnlyTree();
     if (!DstPattern->isLeaf())
-      DstPattern = new TreePatternNode(DstPattern->getOperator(),
-                                       ResultNodeOperands,
-                                       DstPattern->getNumTypes());
+      DstPattern = std::make_shared<TreePatternNode>(DstPattern->getOperator(),
+                                                     ResultNodeOperands,
+                                                     DstPattern->getNumTypes());
 
     for (unsigned i = 0, e = Result.getOnlyTree()->getNumTypes(); i != e; ++i)
       DstPattern->setType(i, Result.getOnlyTree()->getExtType(i));
@@ -4040,18 +4036,17 @@ void CodeGenDAGPatterns::ParsePatterns() {
     // that register class does not accept that type, the type inference
     // will lead to a contradiction, which is not an error however, but
     // a sign that this pattern will simply never match.
-    if (Pattern->getTree(0)->hasPossibleType() &&
+    if (Pattern.getTree(0)->hasPossibleType() &&
         Temp.getOnlyTree()->hasPossibleType()) {
       ListInit *Preds = CurPattern->getValueAsListInit("Predicates");
       int Complexity = CurPattern->getValueAsInt("AddedComplexity");
       if (PatternRewriter)
-        PatternRewriter(Pattern);
-      AddPatternToMatch(
-          Pattern,
-          PatternToMatch(
-              CurPattern, makePredList(Preds), Pattern->getTree(0),
-              Temp.getOnlyTree(), std::move(InstImpResults), Complexity,
-              CurPattern->getID()));
+        PatternRewriter(&Pattern);
+      AddPatternToMatch(&Pattern,
+                        PatternToMatch(CurPattern, makePredList(Preds),
+                                       Pattern.getTree(0), Temp.getOnlyTree(),
+                                       std::move(InstImpResults), Complexity,
+                                       CurPattern->getID()));
     }
   }
 }
@@ -4071,12 +4066,10 @@ void CodeGenDAGPatterns::ExpandHwModeBasedTypes() {
   std::vector<PatternToMatch> Copy = PatternsToMatch;
   PatternsToMatch.clear();
 
-  auto AppendPattern = [this,&ModeChecks](PatternToMatch &P, unsigned Mode) {
-    TreePatternNode *NewSrc = P.SrcPattern->clone();
-    TreePatternNode *NewDst = P.DstPattern->clone();
+  auto AppendPattern = [this, &ModeChecks](PatternToMatch &P, unsigned Mode) {
+    TreePatternNodePtr NewSrc = P.SrcPattern->clone();
+    TreePatternNodePtr NewDst = P.DstPattern->clone();
     if (!NewSrc->setDefaultMode(Mode) || !NewDst->setDefaultMode(Mode)) {
-      delete NewSrc;
-      delete NewDst;
       return;
     }
 
@@ -4089,7 +4082,7 @@ void CodeGenDAGPatterns::ExpandHwModeBasedTypes() {
   };
 
   for (PatternToMatch &P : Copy) {
-    TreePatternNode *SrcP = nullptr, *DstP = nullptr;
+    TreePatternNodePtr SrcP = nullptr, DstP = nullptr;
     if (P.SrcPattern->hasProperTypeByHwMode())
       SrcP = P.SrcPattern;
     if (P.DstPattern->hasProperTypeByHwMode())
@@ -4101,9 +4094,9 @@ void CodeGenDAGPatterns::ExpandHwModeBasedTypes() {
 
     std::set<unsigned> Modes;
     if (SrcP)
-      collectModes(Modes, SrcP);
+      collectModes(Modes, SrcP.get());
     if (DstP)
-      collectModes(Modes, DstP);
+      collectModes(Modes, DstP.get());
 
     // The predicate for the default mode needs to be constructed for each
     // pattern separately.
@@ -4185,11 +4178,11 @@ static void DumpDepVars(MultipleUseVarSet &DepVars) {
 
 /// 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,
-                                 CodeGenDAGPatterns &CDP,
-                                 const MultipleUseVarSet &DepVars) {
+static void CombineChildVariants(
+    TreePatternNodePtr Orig,
+    const std::vector<std::vector<TreePatternNodePtr>> &ChildVariants,
+    std::vector<TreePatternNodePtr> &OutVariants, CodeGenDAGPatterns &CDP,
+    const MultipleUseVarSet &DepVars) {
   // Make sure that each operand has at least one variant to choose from.
   for (const auto &Variants : ChildVariants)
     if (Variants.empty())
@@ -4210,10 +4203,10 @@ static void CombineChildVariants(TreePatternNode *Orig,
     });
 #endif
     // Create the variant and add it to the output list.
-    std::vector<TreePatternNode*> NewChildren;
+    std::vector<TreePatternNodePtr> NewChildren;
     for (unsigned i = 0, e = ChildVariants.size(); i != e; ++i)
       NewChildren.push_back(ChildVariants[i][Idxs[i]]);
-    auto R = llvm::make_unique<TreePatternNode>(
+    TreePatternNodePtr R = std::make_shared<TreePatternNode>(
         Orig->getOperator(), NewChildren, Orig->getNumTypes());
 
     // Copy over properties.
@@ -4230,10 +4223,10 @@ static void CombineChildVariants(TreePatternNode *Orig,
     //   (and GPRC:$a, GPRC:$b) -> (and GPRC:$b, GPRC:$a)
     // which are the same pattern.  Ignore the dups.
     if (R->canPatternMatch(ErrString, CDP) &&
-        none_of(OutVariants, [&](TreePatternNode *Variant) {
-          return R->isIsomorphicTo(Variant, DepVars);
+        none_of(OutVariants, [&](TreePatternNodePtr Variant) {
+          return R->isIsomorphicTo(Variant.get(), DepVars);
         }))
-      OutVariants.push_back(R.release());
+      OutVariants.push_back(R);
 
     // Increment indices to the next permutation by incrementing the
     // indices from last index backward, e.g., generate the sequence
@@ -4251,21 +4244,21 @@ static void CombineChildVariants(TreePatternNode *Orig,
 
 /// 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,
+static void CombineChildVariants(TreePatternNodePtr Orig,
+                                 const std::vector<TreePatternNodePtr> &LHS,
+                                 const std::vector<TreePatternNodePtr> &RHS,
+                                 std::vector<TreePatternNodePtr> &OutVariants,
                                  CodeGenDAGPatterns &CDP,
                                  const MultipleUseVarSet &DepVars) {
-  std::vector<std::vector<TreePatternNode*> > ChildVariants;
+  std::vector<std::vector<TreePatternNodePtr>> ChildVariants;
   ChildVariants.push_back(LHS);
   ChildVariants.push_back(RHS);
   CombineChildVariants(Orig, ChildVariants, OutVariants, CDP, DepVars);
 }
 
-
-static void GatherChildrenOfAssociativeOpcode(TreePatternNode *N,
-                                     std::vector<TreePatternNode *> &Children) {
+static void
+GatherChildrenOfAssociativeOpcode(TreePatternNodePtr N,
+                                  std::vector<TreePatternNodePtr> &Children) {
   assert(N->getNumChildren()==2 &&"Associative but doesn't have 2 children!");
   Record *Operator = N->getOperator();
 
@@ -4277,21 +4270,21 @@ static void GatherChildrenOfAssociativeOpcode(TreePatternNode *N,
   }
 
   if (N->getChild(0)->isLeaf() || N->getChild(0)->getOperator() != Operator)
-    Children.push_back(N->getChild(0));
+    Children.push_back(N->getChildShared(0));
   else
-    GatherChildrenOfAssociativeOpcode(N->getChild(0), Children);
+    GatherChildrenOfAssociativeOpcode(N->getChildShared(0), Children);
 
   if (N->getChild(1)->isLeaf() || N->getChild(1)->getOperator() != Operator)
-    Children.push_back(N->getChild(1));
+    Children.push_back(N->getChildShared(1));
   else
-    GatherChildrenOfAssociativeOpcode(N->getChild(1), Children);
+    GatherChildrenOfAssociativeOpcode(N->getChildShared(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,
+static void GenerateVariantsOf(TreePatternNodePtr N,
+                               std::vector<TreePatternNodePtr> &OutVariants,
                                CodeGenDAGPatterns &CDP,
                                const MultipleUseVarSet &DepVars) {
   // We cannot permute leaves or ComplexPattern uses.
@@ -4306,14 +4299,14 @@ static void GenerateVariantsOf(TreePatternNode *N,
   // If this node is associative, re-associate.
   if (NodeInfo.hasProperty(SDNPAssociative)) {
     // Re-associate by pulling together all of the linked operators
-    std::vector<TreePatternNode*> MaximalChildren;
+    std::vector<TreePatternNodePtr> 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;
+      std::vector<TreePatternNodePtr> AVariants, BVariants, CVariants;
       GenerateVariantsOf(MaximalChildren[0], AVariants, CDP, DepVars);
       GenerateVariantsOf(MaximalChildren[1], BVariants, CDP, DepVars);
       GenerateVariantsOf(MaximalChildren[2], CVariants, CDP, DepVars);
@@ -4323,12 +4316,12 @@ static void GenerateVariantsOf(TreePatternNode *N,
       // 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;
+      std::vector<TreePatternNodePtr> ABVariants;
+      std::vector<TreePatternNodePtr> BAVariants;
+      std::vector<TreePatternNodePtr> ACVariants;
+      std::vector<TreePatternNodePtr> CAVariants;
+      std::vector<TreePatternNodePtr> BCVariants;
+      std::vector<TreePatternNodePtr> CBVariants;
       CombineChildVariants(N, AVariants, BVariants, ABVariants, CDP, DepVars);
       CombineChildVariants(N, BVariants, AVariants, BAVariants, CDP, DepVars);
       CombineChildVariants(N, AVariants, CVariants, ACVariants, CDP, DepVars);
@@ -4356,10 +4349,10 @@ static void GenerateVariantsOf(TreePatternNode *N,
   }
 
   // Compute permutations of all children.
-  std::vector<std::vector<TreePatternNode*> > ChildVariants;
+  std::vector<std::vector<TreePatternNodePtr>> ChildVariants;
   ChildVariants.resize(N->getNumChildren());
   for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i)
-    GenerateVariantsOf(N->getChild(i), ChildVariants[i], CDP, DepVars);
+    GenerateVariantsOf(N->getChildShared(i), ChildVariants[i], CDP, DepVars);
 
   // Build all permutations based on how the children were formed.
   CombineChildVariants(N, ChildVariants, OutVariants, CDP, DepVars);
@@ -4388,7 +4381,7 @@ static void GenerateVariantsOf(TreePatternNode *N,
       // after those.
       assert(NC >= 3 &&
              "Commutative intrinsic should have at least 3 children!");
-      std::vector<std::vector<TreePatternNode*> > Variants;
+      std::vector<std::vector<TreePatternNodePtr>> Variants;
       Variants.push_back(ChildVariants[0]); // Intrinsic id.
       Variants.push_back(ChildVariants[2]);
       Variants.push_back(ChildVariants[1]);
@@ -4396,7 +4389,7 @@ static void GenerateVariantsOf(TreePatternNode *N,
         Variants.push_back(ChildVariants[i]);
       CombineChildVariants(N, Variants, OutVariants, CDP, DepVars);
     } else if (NC == N->getNumChildren()) {
-      std::vector<std::vector<TreePatternNode*> > Variants;
+      std::vector<std::vector<TreePatternNodePtr>> Variants;
       Variants.push_back(ChildVariants[1]);
       Variants.push_back(ChildVariants[0]);
       for (unsigned i = 2; i != NC; ++i)
@@ -4423,13 +4416,13 @@ void CodeGenDAGPatterns::GenerateVariants() {
   //
   for (unsigned i = 0, e = PatternsToMatch.size(); i != e; ++i) {
     MultipleUseVarSet             DepVars;
-    std::vector<TreePatternNode*> Variants;
+    std::vector<TreePatternNodePtr> Variants;
     FindDepVars(PatternsToMatch[i].getSrcPattern(), DepVars);
     LLVM_DEBUG(errs() << "Dependent/multiply used variables: ");
     LLVM_DEBUG(DumpDepVars(DepVars));
     LLVM_DEBUG(errs() << "\n");
-    GenerateVariantsOf(PatternsToMatch[i].getSrcPattern(), Variants, *this,
-                       DepVars);
+    GenerateVariantsOf(PatternsToMatch[i].getSrcPatternShared(), Variants,
+                       *this, DepVars);
 
     assert(!Variants.empty() && "Must create at least original variant!");
     if (Variants.size() == 1)  // No additional variants for this pattern.
@@ -4439,7 +4432,7 @@ void CodeGenDAGPatterns::GenerateVariants() {
                PatternsToMatch[i].getSrcPattern()->dump(); errs() << "\n");
 
     for (unsigned v = 0, e = Variants.size(); v != e; ++v) {
-      TreePatternNode *Variant = Variants[v];
+      TreePatternNodePtr Variant = Variants[v];
 
       LLVM_DEBUG(errs() << "  VAR#" << v << ": "; Variant->dump();
                  errs() << "\n");
@@ -4465,7 +4458,7 @@ void CodeGenDAGPatterns::GenerateVariants() {
       // Otherwise, add it to the list of patterns we have.
       PatternsToMatch.push_back(PatternToMatch(
           PatternsToMatch[i].getSrcRecord(), PatternsToMatch[i].getPredicates(),
-          Variant, PatternsToMatch[i].getDstPattern(),
+          Variant, PatternsToMatch[i].getDstPatternShared(),
           PatternsToMatch[i].getDstRegs(),
           PatternsToMatch[i].getAddedComplexity(), Record::getNewUID()));
     }