clang  6.0.0svn
ASTDiff.cpp
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1 //===- ASTDiff.cpp - AST differencing implementation-----------*- C++ -*- -===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains definitons for the AST differencing interface.
11 //
12 //===----------------------------------------------------------------------===//
13 
15 
17 #include "clang/Lex/Lexer.h"
18 #include "llvm/ADT/PriorityQueue.h"
19 
20 #include <limits>
21 #include <memory>
22 #include <unordered_set>
23 
24 using namespace llvm;
25 using namespace clang;
26 
27 namespace clang {
28 namespace diff {
29 
30 namespace {
31 /// Maps nodes of the left tree to ones on the right, and vice versa.
32 class Mapping {
33 public:
34  Mapping() = default;
35  Mapping(Mapping &&Other) = default;
36  Mapping &operator=(Mapping &&Other) = default;
37 
38  Mapping(size_t Size) {
39  SrcToDst = llvm::make_unique<NodeId[]>(Size);
40  DstToSrc = llvm::make_unique<NodeId[]>(Size);
41  }
42 
43  void link(NodeId Src, NodeId Dst) {
44  SrcToDst[Src] = Dst, DstToSrc[Dst] = Src;
45  }
46 
47  NodeId getDst(NodeId Src) const { return SrcToDst[Src]; }
48  NodeId getSrc(NodeId Dst) const { return DstToSrc[Dst]; }
49  bool hasSrc(NodeId Src) const { return getDst(Src).isValid(); }
50  bool hasDst(NodeId Dst) const { return getSrc(Dst).isValid(); }
51 
52 private:
53  std::unique_ptr<NodeId[]> SrcToDst, DstToSrc;
54 };
55 } // end anonymous namespace
56 
58 public:
60  Mapping TheMapping;
61 
63  const ComparisonOptions &Options);
64 
65  /// Matches nodes one-by-one based on their similarity.
66  void computeMapping();
67 
68  // Compute Change for each node based on similarity.
69  void computeChangeKinds(Mapping &M);
70 
71  NodeId getMapped(const std::unique_ptr<SyntaxTree::Impl> &Tree,
72  NodeId Id) const {
73  if (&*Tree == &T1)
74  return TheMapping.getDst(Id);
75  assert(&*Tree == &T2 && "Invalid tree.");
76  return TheMapping.getSrc(Id);
77  }
78 
79 private:
80  // Returns true if the two subtrees are identical.
81  bool identical(NodeId Id1, NodeId Id2) const;
82 
83  // Returns false if the nodes must not be mached.
84  bool isMatchingPossible(NodeId Id1, NodeId Id2) const;
85 
86  // Returns true if the nodes' parents are matched.
87  bool haveSameParents(const Mapping &M, NodeId Id1, NodeId Id2) const;
88 
89  // Uses an optimal albeit slow algorithm to compute a mapping between two
90  // subtrees, but only if both have fewer nodes than MaxSize.
91  void addOptimalMapping(Mapping &M, NodeId Id1, NodeId Id2) const;
92 
93  // Computes the ratio of common descendants between the two nodes.
94  // Descendants are only considered to be equal when they are mapped in M.
95  double getJaccardSimilarity(const Mapping &M, NodeId Id1, NodeId Id2) const;
96 
97  // Returns the node that has the highest degree of similarity.
98  NodeId findCandidate(const Mapping &M, NodeId Id1) const;
99 
100  // Returns a mapping of identical subtrees.
101  Mapping matchTopDown() const;
102 
103  // Tries to match any yet unmapped nodes, in a bottom-up fashion.
104  void matchBottomUp(Mapping &M) const;
105 
106  const ComparisonOptions &Options;
107 
108  friend class ZhangShashaMatcher;
109 };
110 
111 /// Represents the AST of a TranslationUnit.
113 public:
115  /// Constructs a tree from an AST node.
116  Impl(SyntaxTree *Parent, Decl *N, ASTContext &AST);
117  Impl(SyntaxTree *Parent, Stmt *N, ASTContext &AST);
118  template <class T>
119  Impl(SyntaxTree *Parent,
120  typename std::enable_if<std::is_base_of<Stmt, T>::value, T>::type *Node,
121  ASTContext &AST)
122  : Impl(Parent, dyn_cast<Stmt>(Node), AST) {}
123  template <class T>
124  Impl(SyntaxTree *Parent,
125  typename std::enable_if<std::is_base_of<Decl, T>::value, T>::type *Node,
126  ASTContext &AST)
127  : Impl(Parent, dyn_cast<Decl>(Node), AST) {}
128 
132  /// Nodes in preorder.
133  std::vector<Node> Nodes;
134  std::vector<NodeId> Leaves;
135  // Maps preorder indices to postorder ones.
136  std::vector<int> PostorderIds;
137  std::vector<NodeId> NodesBfs;
138 
139  int getSize() const { return Nodes.size(); }
140  NodeId getRootId() const { return 0; }
141  PreorderIterator begin() const { return getRootId(); }
142  PreorderIterator end() const { return getSize(); }
143 
144  const Node &getNode(NodeId Id) const { return Nodes[Id]; }
145  Node &getMutableNode(NodeId Id) { return Nodes[Id]; }
146  bool isValidNodeId(NodeId Id) const { return Id >= 0 && Id < getSize(); }
147  void addNode(Node &N) { Nodes.push_back(N); }
148  int getNumberOfDescendants(NodeId Id) const;
149  bool isInSubtree(NodeId Id, NodeId SubtreeRoot) const;
150  int findPositionInParent(NodeId Id, bool Shifted = false) const;
151 
152  std::string getRelativeName(const NamedDecl *ND,
153  const DeclContext *Context) const;
154  std::string getRelativeName(const NamedDecl *ND) const;
155 
156  std::string getNodeValue(NodeId Id) const;
157  std::string getNodeValue(const Node &Node) const;
158  std::string getDeclValue(const Decl *D) const;
159  std::string getStmtValue(const Stmt *S) const;
160 
161 private:
162  void initTree();
163  void setLeftMostDescendants();
164 };
165 
166 static bool isSpecializedNodeExcluded(const Decl *D) { return D->isImplicit(); }
167 static bool isSpecializedNodeExcluded(const Stmt *S) { return false; }
169  return !I->isWritten();
170 }
171 
172 template <class T>
173 static bool isNodeExcluded(const SourceManager &SrcMgr, T *N) {
174  if (!N)
175  return true;
176  SourceLocation SLoc = N->getSourceRange().getBegin();
177  if (SLoc.isValid()) {
178  // Ignore everything from other files.
179  if (!SrcMgr.isInMainFile(SLoc))
180  return true;
181  // Ignore macros.
182  if (SLoc != SrcMgr.getSpellingLoc(SLoc))
183  return true;
184  }
185  return isSpecializedNodeExcluded(N);
186 }
187 
188 namespace {
189 // Sets Height, Parent and Children for each node.
190 struct PreorderVisitor : public RecursiveASTVisitor<PreorderVisitor> {
191  int Id = 0, Depth = 0;
192  NodeId Parent;
193  SyntaxTree::Impl &Tree;
194 
195  PreorderVisitor(SyntaxTree::Impl &Tree) : Tree(Tree) {}
196 
197  template <class T> std::tuple<NodeId, NodeId> PreTraverse(T *ASTNode) {
198  NodeId MyId = Id;
199  Tree.Nodes.emplace_back();
200  Node &N = Tree.getMutableNode(MyId);
201  N.Parent = Parent;
202  N.Depth = Depth;
203  N.ASTNode = DynTypedNode::create(*ASTNode);
204  assert(!N.ASTNode.getNodeKind().isNone() &&
205  "Expected nodes to have a valid kind.");
206  if (Parent.isValid()) {
207  Node &P = Tree.getMutableNode(Parent);
208  P.Children.push_back(MyId);
209  }
210  Parent = MyId;
211  ++Id;
212  ++Depth;
213  return std::make_tuple(MyId, Tree.getNode(MyId).Parent);
214  }
215  void PostTraverse(std::tuple<NodeId, NodeId> State) {
216  NodeId MyId, PreviousParent;
217  std::tie(MyId, PreviousParent) = State;
218  assert(MyId.isValid() && "Expecting to only traverse valid nodes.");
219  Parent = PreviousParent;
220  --Depth;
221  Node &N = Tree.getMutableNode(MyId);
222  N.RightMostDescendant = Id - 1;
223  assert(N.RightMostDescendant >= 0 &&
224  N.RightMostDescendant < Tree.getSize() &&
225  "Rightmost descendant must be a valid tree node.");
226  if (N.isLeaf())
227  Tree.Leaves.push_back(MyId);
228  N.Height = 1;
229  for (NodeId Child : N.Children)
230  N.Height = std::max(N.Height, 1 + Tree.getNode(Child).Height);
231  }
232  bool TraverseDecl(Decl *D) {
233  if (isNodeExcluded(Tree.AST.getSourceManager(), D))
234  return true;
235  auto SavedState = PreTraverse(D);
237  PostTraverse(SavedState);
238  return true;
239  }
240  bool TraverseStmt(Stmt *S) {
241  if (S)
242  S = S->IgnoreImplicit();
243  if (isNodeExcluded(Tree.AST.getSourceManager(), S))
244  return true;
245  auto SavedState = PreTraverse(S);
247  PostTraverse(SavedState);
248  return true;
249  }
250  bool TraverseType(QualType T) { return true; }
251  bool TraverseConstructorInitializer(CXXCtorInitializer *Init) {
252  if (isNodeExcluded(Tree.AST.getSourceManager(), Init))
253  return true;
254  auto SavedState = PreTraverse(Init);
256  PostTraverse(SavedState);
257  return true;
258  }
259 };
260 } // end anonymous namespace
261 
262 SyntaxTree::Impl::Impl(SyntaxTree *Parent, ASTContext &AST)
263  : Parent(Parent), AST(AST), TypePP(AST.getLangOpts()) {
265 }
266 
268  : Impl(Parent, AST) {
269  PreorderVisitor PreorderWalker(*this);
270  PreorderWalker.TraverseDecl(N);
271  initTree();
272 }
273 
275  : Impl(Parent, AST) {
276  PreorderVisitor PreorderWalker(*this);
277  PreorderWalker.TraverseStmt(N);
278  initTree();
279 }
280 
281 static std::vector<NodeId> getSubtreePostorder(const SyntaxTree::Impl &Tree,
282  NodeId Root) {
283  std::vector<NodeId> Postorder;
284  std::function<void(NodeId)> Traverse = [&](NodeId Id) {
285  const Node &N = Tree.getNode(Id);
286  for (NodeId Child : N.Children)
287  Traverse(Child);
288  Postorder.push_back(Id);
289  };
290  Traverse(Root);
291  return Postorder;
292 }
293 
294 static std::vector<NodeId> getSubtreeBfs(const SyntaxTree::Impl &Tree,
295  NodeId Root) {
296  std::vector<NodeId> Ids;
297  size_t Expanded = 0;
298  Ids.push_back(Root);
299  while (Expanded < Ids.size())
300  for (NodeId Child : Tree.getNode(Ids[Expanded++]).Children)
301  Ids.push_back(Child);
302  return Ids;
303 }
304 
305 void SyntaxTree::Impl::initTree() {
306  setLeftMostDescendants();
307  int PostorderId = 0;
308  PostorderIds.resize(getSize());
309  std::function<void(NodeId)> PostorderTraverse = [&](NodeId Id) {
310  for (NodeId Child : getNode(Id).Children)
311  PostorderTraverse(Child);
312  PostorderIds[Id] = PostorderId;
313  ++PostorderId;
314  };
315  PostorderTraverse(getRootId());
316  NodesBfs = getSubtreeBfs(*this, getRootId());
317 }
318 
319 void SyntaxTree::Impl::setLeftMostDescendants() {
320  for (NodeId Leaf : Leaves) {
321  getMutableNode(Leaf).LeftMostDescendant = Leaf;
322  NodeId Parent, Cur = Leaf;
323  while ((Parent = getNode(Cur).Parent).isValid() &&
324  getNode(Parent).Children[0] == Cur) {
325  Cur = Parent;
327  }
328  }
329 }
330 
332  return getNode(Id).RightMostDescendant - Id + 1;
333 }
334 
335 bool SyntaxTree::Impl::isInSubtree(NodeId Id, NodeId SubtreeRoot) const {
336  return Id >= SubtreeRoot && Id <= getNode(SubtreeRoot).RightMostDescendant;
337 }
338 
340  NodeId Parent = getNode(Id).Parent;
341  if (Parent.isInvalid())
342  return 0;
343  const auto &Siblings = getNode(Parent).Children;
344  int Position = 0;
345  for (size_t I = 0, E = Siblings.size(); I < E; ++I) {
346  if (Shifted)
347  Position += getNode(Siblings[I]).Shift;
348  if (Siblings[I] == Id) {
349  Position += I;
350  return Position;
351  }
352  }
353  llvm_unreachable("Node not found in parent's children.");
354 }
355 
356 // Returns the qualified name of ND. If it is subordinate to Context,
357 // then the prefix of the latter is removed from the returned value.
358 std::string
360  const DeclContext *Context) const {
361  std::string Val = ND->getQualifiedNameAsString();
362  std::string ContextPrefix;
363  if (!Context)
364  return Val;
365  if (auto *Namespace = dyn_cast<NamespaceDecl>(Context))
366  ContextPrefix = Namespace->getQualifiedNameAsString();
367  else if (auto *Record = dyn_cast<RecordDecl>(Context))
368  ContextPrefix = Record->getQualifiedNameAsString();
369  else if (AST.getLangOpts().CPlusPlus11)
370  if (auto *Tag = dyn_cast<TagDecl>(Context))
371  ContextPrefix = Tag->getQualifiedNameAsString();
372  // Strip the qualifier, if Val refers to somthing in the current scope.
373  // But leave one leading ':' in place, so that we know that this is a
374  // relative path.
375  if (!ContextPrefix.empty() && StringRef(Val).startswith(ContextPrefix))
376  Val = Val.substr(ContextPrefix.size() + 1);
377  return Val;
378 }
379 
380 std::string SyntaxTree::Impl::getRelativeName(const NamedDecl *ND) const {
381  return getRelativeName(ND, ND->getDeclContext());
382 }
383 
385  const Stmt *S) {
386  while (S) {
387  const auto &Parents = AST.getParents(*S);
388  if (Parents.empty())
389  return nullptr;
390  const auto &P = Parents[0];
391  if (const auto *D = P.get<Decl>())
392  return D->getDeclContext();
393  S = P.get<Stmt>();
394  }
395  return nullptr;
396 }
397 
398 static std::string getInitializerValue(const CXXCtorInitializer *Init,
399  const PrintingPolicy &TypePP) {
400  if (Init->isAnyMemberInitializer())
401  return Init->getAnyMember()->getName();
402  if (Init->isBaseInitializer())
403  return QualType(Init->getBaseClass(), 0).getAsString(TypePP);
404  if (Init->isDelegatingInitializer())
405  return Init->getTypeSourceInfo()->getType().getAsString(TypePP);
406  llvm_unreachable("Unknown initializer type");
407 }
408 
410  return getNodeValue(getNode(Id));
411 }
412 
413 std::string SyntaxTree::Impl::getNodeValue(const Node &N) const {
414  const DynTypedNode &DTN = N.ASTNode;
415  if (auto *S = DTN.get<Stmt>())
416  return getStmtValue(S);
417  if (auto *D = DTN.get<Decl>())
418  return getDeclValue(D);
419  if (auto *Init = DTN.get<CXXCtorInitializer>())
420  return getInitializerValue(Init, TypePP);
421  llvm_unreachable("Fatal: unhandled AST node.\n");
422 }
423 
424 std::string SyntaxTree::Impl::getDeclValue(const Decl *D) const {
425  std::string Value;
426  if (auto *V = dyn_cast<ValueDecl>(D))
427  return getRelativeName(V) + "(" + V->getType().getAsString(TypePP) + ")";
428  if (auto *N = dyn_cast<NamedDecl>(D))
429  Value += getRelativeName(N) + ";";
430  if (auto *T = dyn_cast<TypedefNameDecl>(D))
431  return Value + T->getUnderlyingType().getAsString(TypePP) + ";";
432  if (auto *T = dyn_cast<TypeDecl>(D))
433  if (T->getTypeForDecl())
434  Value +=
435  T->getTypeForDecl()->getCanonicalTypeInternal().getAsString(TypePP) +
436  ";";
437  if (auto *U = dyn_cast<UsingDirectiveDecl>(D))
438  return U->getNominatedNamespace()->getName();
439  if (auto *A = dyn_cast<AccessSpecDecl>(D)) {
440  CharSourceRange Range(A->getSourceRange(), false);
441  return Lexer::getSourceText(Range, AST.getSourceManager(),
442  AST.getLangOpts());
443  }
444  return Value;
445 }
446 
447 std::string SyntaxTree::Impl::getStmtValue(const Stmt *S) const {
448  if (auto *U = dyn_cast<UnaryOperator>(S))
449  return UnaryOperator::getOpcodeStr(U->getOpcode());
450  if (auto *B = dyn_cast<BinaryOperator>(S))
451  return B->getOpcodeStr();
452  if (auto *M = dyn_cast<MemberExpr>(S))
453  return getRelativeName(M->getMemberDecl());
454  if (auto *I = dyn_cast<IntegerLiteral>(S)) {
455  SmallString<256> Str;
456  I->getValue().toString(Str, /*Radix=*/10, /*Signed=*/false);
457  return Str.str();
458  }
459  if (auto *F = dyn_cast<FloatingLiteral>(S)) {
460  SmallString<256> Str;
461  F->getValue().toString(Str);
462  return Str.str();
463  }
464  if (auto *D = dyn_cast<DeclRefExpr>(S))
465  return getRelativeName(D->getDecl(), getEnclosingDeclContext(AST, S));
466  if (auto *String = dyn_cast<StringLiteral>(S))
467  return String->getString();
468  if (auto *B = dyn_cast<CXXBoolLiteralExpr>(S))
469  return B->getValue() ? "true" : "false";
470  return "";
471 }
472 
473 /// Identifies a node in a subtree by its postorder offset, starting at 1.
474 struct SNodeId {
475  int Id = 0;
476 
477  explicit SNodeId(int Id) : Id(Id) {}
478  explicit SNodeId() = default;
479 
480  operator int() const { return Id; }
481  SNodeId &operator++() { return ++Id, *this; }
482  SNodeId &operator--() { return --Id, *this; }
483  SNodeId operator+(int Other) const { return SNodeId(Id + Other); }
484 };
485 
486 class Subtree {
487 private:
488  /// The parent tree.
489  const SyntaxTree::Impl &Tree;
490  /// Maps SNodeIds to original ids.
491  std::vector<NodeId> RootIds;
492  /// Maps subtree nodes to their leftmost descendants wtihin the subtree.
493  std::vector<SNodeId> LeftMostDescendants;
494 
495 public:
496  std::vector<SNodeId> KeyRoots;
497 
498  Subtree(const SyntaxTree::Impl &Tree, NodeId SubtreeRoot) : Tree(Tree) {
499  RootIds = getSubtreePostorder(Tree, SubtreeRoot);
500  int NumLeaves = setLeftMostDescendants();
501  computeKeyRoots(NumLeaves);
502  }
503  int getSize() const { return RootIds.size(); }
505  assert(Id > 0 && Id <= getSize() && "Invalid subtree node index.");
506  return RootIds[Id - 1];
507  }
508  const Node &getNode(SNodeId Id) const {
509  return Tree.getNode(getIdInRoot(Id));
510  }
512  assert(Id > 0 && Id <= getSize() && "Invalid subtree node index.");
513  return LeftMostDescendants[Id - 1];
514  }
515  /// Returns the postorder index of the leftmost descendant in the subtree.
517  return Tree.PostorderIds[getIdInRoot(SNodeId(1))];
518  }
519  std::string getNodeValue(SNodeId Id) const {
520  return Tree.getNodeValue(getIdInRoot(Id));
521  }
522 
523 private:
524  /// Returns the number of leafs in the subtree.
525  int setLeftMostDescendants() {
526  int NumLeaves = 0;
527  LeftMostDescendants.resize(getSize());
528  for (int I = 0; I < getSize(); ++I) {
529  SNodeId SI(I + 1);
530  const Node &N = getNode(SI);
531  NumLeaves += N.isLeaf();
532  assert(I == Tree.PostorderIds[getIdInRoot(SI)] - getPostorderOffset() &&
533  "Postorder traversal in subtree should correspond to traversal in "
534  "the root tree by a constant offset.");
535  LeftMostDescendants[I] = SNodeId(Tree.PostorderIds[N.LeftMostDescendant] -
536  getPostorderOffset());
537  }
538  return NumLeaves;
539  }
540  void computeKeyRoots(int Leaves) {
541  KeyRoots.resize(Leaves);
542  std::unordered_set<int> Visited;
543  int K = Leaves - 1;
544  for (SNodeId I(getSize()); I > 0; --I) {
545  SNodeId LeftDesc = getLeftMostDescendant(I);
546  if (Visited.count(LeftDesc))
547  continue;
548  assert(K >= 0 && "K should be non-negative");
549  KeyRoots[K] = I;
550  Visited.insert(LeftDesc);
551  --K;
552  }
553  }
554 };
555 
556 /// Implementation of Zhang and Shasha's Algorithm for tree edit distance.
557 /// Computes an optimal mapping between two trees using only insertion,
558 /// deletion and update as edit actions (similar to the Levenshtein distance).
560  const ASTDiff::Impl &DiffImpl;
561  Subtree S1;
562  Subtree S2;
563  std::unique_ptr<std::unique_ptr<double[]>[]> TreeDist, ForestDist;
564 
565 public:
567  const SyntaxTree::Impl &T2, NodeId Id1, NodeId Id2)
568  : DiffImpl(DiffImpl), S1(T1, Id1), S2(T2, Id2) {
569  TreeDist = llvm::make_unique<std::unique_ptr<double[]>[]>(
570  size_t(S1.getSize()) + 1);
571  ForestDist = llvm::make_unique<std::unique_ptr<double[]>[]>(
572  size_t(S1.getSize()) + 1);
573  for (int I = 0, E = S1.getSize() + 1; I < E; ++I) {
574  TreeDist[I] = llvm::make_unique<double[]>(size_t(S2.getSize()) + 1);
575  ForestDist[I] = llvm::make_unique<double[]>(size_t(S2.getSize()) + 1);
576  }
577  }
578 
579  std::vector<std::pair<NodeId, NodeId>> getMatchingNodes() {
580  std::vector<std::pair<NodeId, NodeId>> Matches;
581  std::vector<std::pair<SNodeId, SNodeId>> TreePairs;
582 
583  computeTreeDist();
584 
585  bool RootNodePair = true;
586 
587  TreePairs.emplace_back(SNodeId(S1.getSize()), SNodeId(S2.getSize()));
588 
589  while (!TreePairs.empty()) {
590  SNodeId LastRow, LastCol, FirstRow, FirstCol, Row, Col;
591  std::tie(LastRow, LastCol) = TreePairs.back();
592  TreePairs.pop_back();
593 
594  if (!RootNodePair) {
595  computeForestDist(LastRow, LastCol);
596  }
597 
598  RootNodePair = false;
599 
600  FirstRow = S1.getLeftMostDescendant(LastRow);
601  FirstCol = S2.getLeftMostDescendant(LastCol);
602 
603  Row = LastRow;
604  Col = LastCol;
605 
606  while (Row > FirstRow || Col > FirstCol) {
607  if (Row > FirstRow &&
608  ForestDist[Row - 1][Col] + 1 == ForestDist[Row][Col]) {
609  --Row;
610  } else if (Col > FirstCol &&
611  ForestDist[Row][Col - 1] + 1 == ForestDist[Row][Col]) {
612  --Col;
613  } else {
614  SNodeId LMD1 = S1.getLeftMostDescendant(Row);
615  SNodeId LMD2 = S2.getLeftMostDescendant(Col);
616  if (LMD1 == S1.getLeftMostDescendant(LastRow) &&
617  LMD2 == S2.getLeftMostDescendant(LastCol)) {
618  NodeId Id1 = S1.getIdInRoot(Row);
619  NodeId Id2 = S2.getIdInRoot(Col);
620  assert(DiffImpl.isMatchingPossible(Id1, Id2) &&
621  "These nodes must not be matched.");
622  Matches.emplace_back(Id1, Id2);
623  --Row;
624  --Col;
625  } else {
626  TreePairs.emplace_back(Row, Col);
627  Row = LMD1;
628  Col = LMD2;
629  }
630  }
631  }
632  }
633  return Matches;
634  }
635 
636 private:
637  /// We use a simple cost model for edit actions, which seems good enough.
638  /// Simple cost model for edit actions. This seems to make the matching
639  /// algorithm perform reasonably well.
640  /// The values range between 0 and 1, or infinity if this edit action should
641  /// always be avoided.
642  static constexpr double DeletionCost = 1;
643  static constexpr double InsertionCost = 1;
644 
645  double getUpdateCost(SNodeId Id1, SNodeId Id2) {
646  if (!DiffImpl.isMatchingPossible(S1.getIdInRoot(Id1), S2.getIdInRoot(Id2)))
648  return S1.getNodeValue(Id1) != S2.getNodeValue(Id2);
649  }
650 
651  void computeTreeDist() {
652  for (SNodeId Id1 : S1.KeyRoots)
653  for (SNodeId Id2 : S2.KeyRoots)
654  computeForestDist(Id1, Id2);
655  }
656 
657  void computeForestDist(SNodeId Id1, SNodeId Id2) {
658  assert(Id1 > 0 && Id2 > 0 && "Expecting offsets greater than 0.");
659  SNodeId LMD1 = S1.getLeftMostDescendant(Id1);
660  SNodeId LMD2 = S2.getLeftMostDescendant(Id2);
661 
662  ForestDist[LMD1][LMD2] = 0;
663  for (SNodeId D1 = LMD1 + 1; D1 <= Id1; ++D1) {
664  ForestDist[D1][LMD2] = ForestDist[D1 - 1][LMD2] + DeletionCost;
665  for (SNodeId D2 = LMD2 + 1; D2 <= Id2; ++D2) {
666  ForestDist[LMD1][D2] = ForestDist[LMD1][D2 - 1] + InsertionCost;
667  SNodeId DLMD1 = S1.getLeftMostDescendant(D1);
668  SNodeId DLMD2 = S2.getLeftMostDescendant(D2);
669  if (DLMD1 == LMD1 && DLMD2 == LMD2) {
670  double UpdateCost = getUpdateCost(D1, D2);
671  ForestDist[D1][D2] =
672  std::min({ForestDist[D1 - 1][D2] + DeletionCost,
673  ForestDist[D1][D2 - 1] + InsertionCost,
674  ForestDist[D1 - 1][D2 - 1] + UpdateCost});
675  TreeDist[D1][D2] = ForestDist[D1][D2];
676  } else {
677  ForestDist[D1][D2] =
678  std::min({ForestDist[D1 - 1][D2] + DeletionCost,
679  ForestDist[D1][D2 - 1] + InsertionCost,
680  ForestDist[DLMD1][DLMD2] + TreeDist[D1][D2]});
681  }
682  }
683  }
684  }
685 };
686 
688  return ASTNode.getNodeKind();
689 }
690 
691 StringRef Node::getTypeLabel() const { return getType().asStringRef(); }
692 
694  if (auto *ND = ASTNode.get<NamedDecl>()) {
695  if (ND->getDeclName().isIdentifier())
696  return ND->getQualifiedNameAsString();
697  }
698  return llvm::None;
699 }
700 
702  if (auto *ND = ASTNode.get<NamedDecl>()) {
703  if (ND->getDeclName().isIdentifier())
704  return ND->getName();
705  }
706  return llvm::None;
707 }
708 
709 namespace {
710 // Compares nodes by their depth.
711 struct HeightLess {
712  const SyntaxTree::Impl &Tree;
713  HeightLess(const SyntaxTree::Impl &Tree) : Tree(Tree) {}
714  bool operator()(NodeId Id1, NodeId Id2) const {
715  return Tree.getNode(Id1).Height < Tree.getNode(Id2).Height;
716  }
717 };
718 } // end anonymous namespace
719 
720 namespace {
721 // Priority queue for nodes, sorted descendingly by their height.
722 class PriorityList {
723  const SyntaxTree::Impl &Tree;
724  HeightLess Cmp;
725  std::vector<NodeId> Container;
726  PriorityQueue<NodeId, std::vector<NodeId>, HeightLess> List;
727 
728 public:
729  PriorityList(const SyntaxTree::Impl &Tree)
730  : Tree(Tree), Cmp(Tree), List(Cmp, Container) {}
731 
732  void push(NodeId id) { List.push(id); }
733 
734  std::vector<NodeId> pop() {
735  int Max = peekMax();
736  std::vector<NodeId> Result;
737  if (Max == 0)
738  return Result;
739  while (peekMax() == Max) {
740  Result.push_back(List.top());
741  List.pop();
742  }
743  // TODO this is here to get a stable output, not a good heuristic
744  std::sort(Result.begin(), Result.end());
745  return Result;
746  }
747  int peekMax() const {
748  if (List.empty())
749  return 0;
750  return Tree.getNode(List.top()).Height;
751  }
752  void open(NodeId Id) {
753  for (NodeId Child : Tree.getNode(Id).Children)
754  push(Child);
755  }
756 };
757 } // end anonymous namespace
758 
759 bool ASTDiff::Impl::identical(NodeId Id1, NodeId Id2) const {
760  const Node &N1 = T1.getNode(Id1);
761  const Node &N2 = T2.getNode(Id2);
762  if (N1.Children.size() != N2.Children.size() ||
763  !isMatchingPossible(Id1, Id2) ||
764  T1.getNodeValue(Id1) != T2.getNodeValue(Id2))
765  return false;
766  for (size_t Id = 0, E = N1.Children.size(); Id < E; ++Id)
767  if (!identical(N1.Children[Id], N2.Children[Id]))
768  return false;
769  return true;
770 }
771 
772 bool ASTDiff::Impl::isMatchingPossible(NodeId Id1, NodeId Id2) const {
773  return Options.isMatchingAllowed(T1.getNode(Id1), T2.getNode(Id2));
774 }
775 
776 bool ASTDiff::Impl::haveSameParents(const Mapping &M, NodeId Id1,
777  NodeId Id2) const {
778  NodeId P1 = T1.getNode(Id1).Parent;
779  NodeId P2 = T2.getNode(Id2).Parent;
780  return (P1.isInvalid() && P2.isInvalid()) ||
781  (P1.isValid() && P2.isValid() && M.getDst(P1) == P2);
782 }
783 
784 void ASTDiff::Impl::addOptimalMapping(Mapping &M, NodeId Id1,
785  NodeId Id2) const {
786  if (std::max(T1.getNumberOfDescendants(Id1), T2.getNumberOfDescendants(Id2)) >
787  Options.MaxSize)
788  return;
789  ZhangShashaMatcher Matcher(*this, T1, T2, Id1, Id2);
790  std::vector<std::pair<NodeId, NodeId>> R = Matcher.getMatchingNodes();
791  for (const auto Tuple : R) {
792  NodeId Src = Tuple.first;
793  NodeId Dst = Tuple.second;
794  if (!M.hasSrc(Src) && !M.hasDst(Dst))
795  M.link(Src, Dst);
796  }
797 }
798 
799 double ASTDiff::Impl::getJaccardSimilarity(const Mapping &M, NodeId Id1,
800  NodeId Id2) const {
801  int CommonDescendants = 0;
802  const Node &N1 = T1.getNode(Id1);
803  // Count the common descendants, excluding the subtree root.
804  for (NodeId Src = Id1 + 1; Src <= N1.RightMostDescendant; ++Src) {
805  NodeId Dst = M.getDst(Src);
806  CommonDescendants += int(Dst.isValid() && T2.isInSubtree(Dst, Id2));
807  }
808  // We need to subtract 1 to get the number of descendants excluding the root.
809  double Denominator = T1.getNumberOfDescendants(Id1) - 1 +
810  T2.getNumberOfDescendants(Id2) - 1 - CommonDescendants;
811  // CommonDescendants is less than the size of one subtree.
812  assert(Denominator >= 0 && "Expected non-negative denominator.");
813  if (Denominator == 0)
814  return 0;
815  return CommonDescendants / Denominator;
816 }
817 
818 NodeId ASTDiff::Impl::findCandidate(const Mapping &M, NodeId Id1) const {
819  NodeId Candidate;
820  double HighestSimilarity = 0.0;
821  for (NodeId Id2 : T2) {
822  if (!isMatchingPossible(Id1, Id2))
823  continue;
824  if (M.hasDst(Id2))
825  continue;
826  double Similarity = getJaccardSimilarity(M, Id1, Id2);
827  if (Similarity >= Options.MinSimilarity && Similarity > HighestSimilarity) {
828  HighestSimilarity = Similarity;
829  Candidate = Id2;
830  }
831  }
832  return Candidate;
833 }
834 
835 void ASTDiff::Impl::matchBottomUp(Mapping &M) const {
836  std::vector<NodeId> Postorder = getSubtreePostorder(T1, T1.getRootId());
837  for (NodeId Id1 : Postorder) {
838  if (Id1 == T1.getRootId() && !M.hasSrc(T1.getRootId()) &&
839  !M.hasDst(T2.getRootId())) {
840  if (isMatchingPossible(T1.getRootId(), T2.getRootId())) {
841  M.link(T1.getRootId(), T2.getRootId());
842  addOptimalMapping(M, T1.getRootId(), T2.getRootId());
843  }
844  break;
845  }
846  bool Matched = M.hasSrc(Id1);
847  const Node &N1 = T1.getNode(Id1);
848  bool MatchedChildren =
849  std::any_of(N1.Children.begin(), N1.Children.end(),
850  [&](NodeId Child) { return M.hasSrc(Child); });
851  if (Matched || !MatchedChildren)
852  continue;
853  NodeId Id2 = findCandidate(M, Id1);
854  if (Id2.isValid()) {
855  M.link(Id1, Id2);
856  addOptimalMapping(M, Id1, Id2);
857  }
858  }
859 }
860 
861 Mapping ASTDiff::Impl::matchTopDown() const {
862  PriorityList L1(T1);
863  PriorityList L2(T2);
864 
865  Mapping M(T1.getSize() + T2.getSize());
866 
867  L1.push(T1.getRootId());
868  L2.push(T2.getRootId());
869 
870  int Max1, Max2;
871  while (std::min(Max1 = L1.peekMax(), Max2 = L2.peekMax()) >
872  Options.MinHeight) {
873  if (Max1 > Max2) {
874  for (NodeId Id : L1.pop())
875  L1.open(Id);
876  continue;
877  }
878  if (Max2 > Max1) {
879  for (NodeId Id : L2.pop())
880  L2.open(Id);
881  continue;
882  }
883  std::vector<NodeId> H1, H2;
884  H1 = L1.pop();
885  H2 = L2.pop();
886  for (NodeId Id1 : H1) {
887  for (NodeId Id2 : H2) {
888  if (identical(Id1, Id2) && !M.hasSrc(Id1) && !M.hasDst(Id2)) {
889  for (int I = 0, E = T1.getNumberOfDescendants(Id1); I < E; ++I)
890  M.link(Id1 + I, Id2 + I);
891  }
892  }
893  }
894  for (NodeId Id1 : H1) {
895  if (!M.hasSrc(Id1))
896  L1.open(Id1);
897  }
898  for (NodeId Id2 : H2) {
899  if (!M.hasDst(Id2))
900  L2.open(Id2);
901  }
902  }
903  return M;
904 }
905 
907  const ComparisonOptions &Options)
908  : T1(T1), T2(T2), Options(Options) {
909  computeMapping();
911 }
912 
914  TheMapping = matchTopDown();
915  if (Options.StopAfterTopDown)
916  return;
917  matchBottomUp(TheMapping);
918 }
919 
921  for (NodeId Id1 : T1) {
922  if (!M.hasSrc(Id1)) {
923  T1.getMutableNode(Id1).Change = Delete;
924  T1.getMutableNode(Id1).Shift -= 1;
925  }
926  }
927  for (NodeId Id2 : T2) {
928  if (!M.hasDst(Id2)) {
929  T2.getMutableNode(Id2).Change = Insert;
930  T2.getMutableNode(Id2).Shift -= 1;
931  }
932  }
933  for (NodeId Id1 : T1.NodesBfs) {
934  NodeId Id2 = M.getDst(Id1);
935  if (Id2.isInvalid())
936  continue;
937  if (!haveSameParents(M, Id1, Id2) ||
938  T1.findPositionInParent(Id1, true) !=
939  T2.findPositionInParent(Id2, true)) {
940  T1.getMutableNode(Id1).Shift -= 1;
941  T2.getMutableNode(Id2).Shift -= 1;
942  }
943  }
944  for (NodeId Id2 : T2.NodesBfs) {
945  NodeId Id1 = M.getSrc(Id2);
946  if (Id1.isInvalid())
947  continue;
948  Node &N1 = T1.getMutableNode(Id1);
949  Node &N2 = T2.getMutableNode(Id2);
950  if (Id1.isInvalid())
951  continue;
952  if (!haveSameParents(M, Id1, Id2) ||
953  T1.findPositionInParent(Id1, true) !=
954  T2.findPositionInParent(Id2, true)) {
955  N1.Change = N2.Change = Move;
956  }
957  if (T1.getNodeValue(Id1) != T2.getNodeValue(Id2)) {
958  N1.Change = N2.Change = (N1.Change == Move ? UpdateMove : Update);
959  }
960  }
961 }
962 
964  const ComparisonOptions &Options)
965  : DiffImpl(llvm::make_unique<Impl>(*T1.TreeImpl, *T2.TreeImpl, Options)) {}
966 
967 ASTDiff::~ASTDiff() = default;
968 
969 NodeId ASTDiff::getMapped(const SyntaxTree &SourceTree, NodeId Id) const {
970  return DiffImpl->getMapped(SourceTree.TreeImpl, Id);
971 }
972 
974  : TreeImpl(llvm::make_unique<SyntaxTree::Impl>(
975  this, AST.getTranslationUnitDecl(), AST)) {}
976 
977 SyntaxTree::~SyntaxTree() = default;
978 
979 const ASTContext &SyntaxTree::getASTContext() const { return TreeImpl->AST; }
980 
982  return TreeImpl->getNode(Id);
983 }
984 
985 int SyntaxTree::getSize() const { return TreeImpl->getSize(); }
986 NodeId SyntaxTree::getRootId() const { return TreeImpl->getRootId(); }
988  return TreeImpl->begin();
989 }
991 
993  return TreeImpl->findPositionInParent(Id);
994 }
995 
996 std::pair<unsigned, unsigned>
998  const SourceManager &SrcMgr = TreeImpl->AST.getSourceManager();
999  SourceRange Range = N.ASTNode.getSourceRange();
1000  SourceLocation BeginLoc = Range.getBegin();
1002  Range.getEnd(), /*Offset=*/0, SrcMgr, TreeImpl->AST.getLangOpts());
1003  if (auto *ThisExpr = N.ASTNode.get<CXXThisExpr>()) {
1004  if (ThisExpr->isImplicit())
1005  EndLoc = BeginLoc;
1006  }
1007  unsigned Begin = SrcMgr.getFileOffset(SrcMgr.getExpansionLoc(BeginLoc));
1008  unsigned End = SrcMgr.getFileOffset(SrcMgr.getExpansionLoc(EndLoc));
1009  return {Begin, End};
1010 }
1011 
1012 std::string SyntaxTree::getNodeValue(NodeId Id) const {
1013  return TreeImpl->getNodeValue(Id);
1014 }
1015 
1016 std::string SyntaxTree::getNodeValue(const Node &N) const {
1017  return TreeImpl->getNodeValue(N);
1018 }
1019 
1020 } // end namespace diff
1021 } // end namespace clang
bool isBaseInitializer() const
Determine whether this initializer is initializing a base class.
Definition: DeclCXX.h:2238
llvm::Optional< std::string > getQualifiedIdentifier() const
Definition: ASTDiff.cpp:693
A (possibly-)qualified type.
Definition: Type.h:653
NodeId Parent
Definition: ASTDiff.h:39
__SIZE_TYPE__ size_t
The unsigned integer type of the result of the sizeof operator.
Definition: opencl-c.h:60
const Node & getNode(NodeId Id) const
Definition: ASTDiff.cpp:981
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:26
Stmt - This represents one statement.
Definition: Stmt.h:66
const T * get() const
Retrieve the stored node as type T.
NodeId getMapped(const SyntaxTree &SourceTree, NodeId Id) const
Definition: ASTDiff.cpp:969
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
bool isInSubtree(NodeId Id, NodeId SubtreeRoot) const
Definition: ASTDiff.cpp:335
ZhangShashaMatcher(const ASTDiff::Impl &DiffImpl, const SyntaxTree::Impl &T1, const SyntaxTree::Impl &T2, NodeId Id1, NodeId Id2)
Definition: ASTDiff.cpp:566
bool isWritten() const
Determine whether this initializer is explicitly written in the source code.
Definition: DeclCXX.h:2337
StringRef P
ast_type_traits::ASTNodeKind getType() const
Definition: ASTDiff.cpp:687
static std::vector< NodeId > getSubtreePostorder(const SyntaxTree::Impl &Tree, NodeId Root)
Definition: ASTDiff.cpp:281
Stmt * IgnoreImplicit()
Skip past any implicit AST nodes which might surround this statement, such as ExprWithCleanups or Imp...
Definition: Stmt.cpp:112
void computeChangeKinds(Mapping &M)
Definition: ASTDiff.cpp:920
void computeMapping()
Matches nodes one-by-one based on their similarity.
Definition: ASTDiff.cpp:913
llvm::Optional< StringRef > getIdentifier() const
Definition: ASTDiff.cpp:701
const Node & getNode(SNodeId Id) const
Definition: ASTDiff.cpp:508
std::vector< NodeId > NodesBfs
Definition: ASTDiff.cpp:137
PreorderIterator end() const
Definition: ASTDiff.cpp:142
bool isValid() const
std::vector< NodeId > Leaves
Definition: ASTDiff.cpp:134
Describes how types, statements, expressions, and declarations should be printed. ...
Definition: PrettyPrinter.h:38
NodeId getMapped(const std::unique_ptr< SyntaxTree::Impl > &Tree, NodeId Id) const
Definition: ASTDiff.cpp:71
bool isValidNodeId(NodeId Id) const
Definition: ASTDiff.cpp:146
std::vector< SNodeId > KeyRoots
Definition: ASTDiff.cpp:496
SNodeId operator+(int Other) const
Definition: ASTDiff.cpp:483
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:149
LineState State
TypeSourceInfo * getTypeSourceInfo() const
Returns the declarator information for a base class or delegating initializer.
Definition: DeclCXX.h:2299
DynTypedNodeList getParents(const NodeT &Node)
Returns the parents of the given node.
Definition: ASTContext.h:629
std::string getNodeValue(NodeId Id) const
Definition: ASTDiff.cpp:409
SyntaxTree::Impl & T2
Definition: ASTDiff.cpp:59
std::string getNodeValue(SNodeId Id) const
Definition: ASTDiff.cpp:519
Implementation of Zhang and Shasha&#39;s Algorithm for tree edit distance.
Definition: ASTDiff.cpp:559
Within a tree, this identifies a node by its preorder offset.
NodeId getPostorderOffset() const
Returns the postorder index of the leftmost descendant in the subtree.
Definition: ASTDiff.cpp:516
ast_type_traits::DynTypedNode ASTNode
Definition: ASTDiff.h:41
SourceLocation getExpansionLoc(SourceLocation Loc) const
Given a SourceLocation object Loc, return the expansion location referenced by the ID...
std::string getAsString() const
Definition: Type.h:979
SNodeId & operator++()
Definition: ASTDiff.cpp:481
std::string getNodeValue(NodeId Id) const
Serialize the node attributes to a string representation.
Definition: ASTDiff.cpp:1012
ChangeKind Change
Definition: ASTDiff.h:43
bool isAnyMemberInitializer() const
Definition: DeclCXX.h:2246
std::unique_ptr< Impl > TreeImpl
Definition: ASTDiff.h:100
SyntaxTree::Impl & T1
Definition: ASTDiff.cpp:59
SourceLocation getSpellingLoc(SourceLocation Loc) const
Given a SourceLocation object, return the spelling location referenced by the ID. ...
FieldDecl * getAnyMember() const
Definition: DeclCXX.h:2311
int findPositionInParent(NodeId Id) const
Definition: ASTDiff.cpp:992
A class that does preorder or postorder depth-first traversal on the entire Clang AST and visits each...
std::string getStmtValue(const Stmt *S) const
Definition: ASTDiff.cpp:447
Represents the this expression in C++.
Definition: ExprCXX.h:945
int getNumberOfDescendants(NodeId Id) const
Definition: ASTDiff.cpp:331
NodeId Parent
Definition: ASTDiff.cpp:192
Impl(SyntaxTree *Parent, ASTContext &AST)
Definition: ASTDiff.cpp:262
static std::string getInitializerValue(const CXXCtorInitializer *Init, const PrintingPolicy &TypePP)
Definition: ASTDiff.cpp:398
ASTDiff(SyntaxTree &Src, SyntaxTree &Dst, const ComparisonOptions &Options)
Definition: ASTDiff.cpp:963
bool isDelegatingInitializer() const
Determine whether this initializer is creating a delegating constructor.
Definition: DeclCXX.h:2266
Impl(SyntaxTree *Parent, typename std::enable_if< std::is_base_of< Decl, T >::value, T >::type *Node, ASTContext &AST)
Definition: ASTDiff.cpp:124
NodeId RightMostDescendant
Definition: ASTDiff.h:39
PreorderIterator end() const
Definition: ASTDiff.cpp:990
static StringRef getSourceText(CharSourceRange Range, const SourceManager &SM, const LangOptions &LangOpts, bool *Invalid=nullptr)
Returns a string for the source that the range encompasses.
Definition: Lexer.cpp:934
Identifies a node in a subtree by its postorder offset, starting at 1.
Definition: ASTDiff.cpp:474
static SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset, const SourceManager &SM, const LangOptions &LangOpts)
Computes the source location just past the end of the token at this source location.
Definition: Lexer.cpp:773
SourceLocation End
Represents a character-granular source range.
llvm::StringRef getAsString(SyncScope S)
Definition: SyncScope.h:51
int Id
Definition: ASTDiff.cpp:191
const FunctionProtoType * T
bool isImplicit() const
isImplicit - Indicates whether the declaration was implicitly generated by the implementation.
Definition: DeclBase.h:551
static std::vector< NodeId > getSubtreeBfs(const SyntaxTree::Impl &Tree, NodeId Root)
Definition: ASTDiff.cpp:294
PreorderIterator begin() const
Definition: ASTDiff.cpp:141
DeclContext * getDeclContext()
Definition: DeclBase.h:425
SourceLocation Begin
const ASTContext & getASTContext() const
Definition: ASTDiff.cpp:979
char __ovld __cnfn min(char x, char y)
Returns y if y < x, otherwise it returns x.
int Depth
Definition: ASTDiff.cpp:191
SourceRange getSourceRange() const
For nodes which represent textual entities in the source code, return their SourceRange.
SourceLocation getEnd() const
bool isLeaf() const
Definition: ASTDiff.h:47
unsigned getFileOffset(SourceLocation SpellingLoc) const
Returns the offset from the start of the file that the specified SourceLocation represents.
Encodes a location in the source.
PreorderIterator begin() const
Definition: ASTDiff.cpp:987
SyntaxTree(ASTContext &AST)
Constructs a tree from a translation unit.
Definition: ASTDiff.cpp:973
std::string getRelativeName(const NamedDecl *ND, const DeclContext *Context) const
Definition: ASTDiff.cpp:359
std::vector< int > PostorderIds
Definition: ASTDiff.cpp:136
StringRef getTypeLabel() const
Definition: ASTDiff.cpp:691
std::vector< Node > Nodes
Nodes in preorder.
Definition: ASTDiff.cpp:133
SyntaxTree objects represent subtrees of the AST.
Definition: ASTDiff.h:68
SmallVector< NodeId, 4 > Children
Definition: ASTDiff.h:42
Subtree(const SyntaxTree::Impl &Tree, NodeId SubtreeRoot)
Definition: ASTDiff.cpp:498
NodeId getIdInRoot(SNodeId Id) const
Definition: ASTDiff.cpp:504
bool isInMainFile(SourceLocation Loc) const
Returns whether the PresumedLoc for a given SourceLocation is in the main file.
int getSize() const
Definition: ASTDiff.cpp:503
ast_type_traits::DynTypedNode Node
NodeId getRootId() const
Definition: ASTDiff.cpp:986
static bool isNodeExcluded(const SourceManager &SrcMgr, T *N)
Definition: ASTDiff.cpp:173
Dataflow Directional Tag Classes.
bool isValid() const
Return true if this is a valid SourceLocation object.
std::pair< unsigned, unsigned > getSourceRangeOffsets(const Node &N) const
Definition: ASTDiff.cpp:997
DeclContext - This is used only as base class of specific decl types that can act as declaration cont...
Definition: DeclBase.h:1252
Node & getMutableNode(NodeId Id)
Definition: ASTDiff.cpp:145
int findPositionInParent(NodeId Id, bool Shifted=false) const
Definition: ASTDiff.cpp:339
std::unique_ptr< DiagnosticConsumer > create(StringRef OutputFile, DiagnosticOptions *Diags, bool MergeChildRecords=false)
Returns a DiagnosticConsumer that serializes diagnostics to a bitcode file.
const Type * getBaseClass() const
If this is a base class initializer, returns the type of the base class.
Definition: DeclCXX.cpp:2014
Represents the AST of a TranslationUnit.
Definition: ASTDiff.cpp:112
NodeId LeftMostDescendant
Definition: ASTDiff.h:39
Impl(SyntaxTree::Impl &T1, SyntaxTree::Impl &T2, const ComparisonOptions &Options)
Definition: ASTDiff.cpp:906
SyntaxTree::Impl & Tree
Definition: ASTDiff.cpp:193
A dynamically typed AST node container.
SNodeId getLeftMostDescendant(SNodeId Id) const
Definition: ASTDiff.cpp:511
QualType getCanonicalTypeInternal() const
Definition: Type.h:2109
Represents a C++ base or member initializer.
Definition: DeclCXX.h:2172
char __ovld __cnfn max(char x, char y)
Returns y if x < y, otherwise it returns x.
SourceManager & getSourceManager()
Definition: ASTContext.h:643
std::string getDeclValue(const Decl *D) const
Definition: ASTDiff.cpp:424
static const DeclContext * getEnclosingDeclContext(ASTContext &AST, const Stmt *S)
Definition: ASTDiff.cpp:384
std::vector< std::pair< NodeId, NodeId > > getMatchingNodes()
Definition: ASTDiff.cpp:579
bool isInvalid() const
StringRef getName() const
getName - Get the name of identifier for this declaration as a StringRef.
Definition: Decl.h:270
bool AnonymousTagLocations
When printing an anonymous tag name, also print the location of that entity (e.g., "enum <anonymous at t.h:10:5>").
std::string getQualifiedNameAsString() const
Definition: Decl.cpp:1471
const Node & getNode(NodeId Id) const
Definition: ASTDiff.cpp:144
A trivial tuple used to represent a source range.
static StringRef getOpcodeStr(Opcode Op)
getOpcodeStr - Turn an Opcode enum value into the punctuation char it corresponds to...
Definition: Expr.cpp:1116
NamedDecl - This represents a decl with a name.
Definition: Decl.h:245
Represents a Clang AST node, alongside some additional information.
Definition: ASTDiff.h:38
SourceLocation getBegin() const
const LangOptions & getLangOpts() const
Definition: ASTContext.h:688
SNodeId & operator--()
Definition: ASTDiff.cpp:482
This class handles loading and caching of source files into memory.
Impl(SyntaxTree *Parent, typename std::enable_if< std::is_base_of< Stmt, T >::value, T >::type *Node, ASTContext &AST)
Definition: ASTDiff.cpp:119
QualType getType() const
Return the type wrapped by this type source info.
Definition: Decl.h:97
static bool isSpecializedNodeExcluded(CXXCtorInitializer *I)
Definition: ASTDiff.cpp:168