clang  3.7.0
ASTMatchersInternal.cpp
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1 //===--- ASTMatchersInternal.cpp - Structural query framework -------------===//
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 // Implements the base layer of the matcher framework.
11 //
12 //===----------------------------------------------------------------------===//
13 
16 #include "llvm/ADT/SmallString.h"
17 #include "llvm/Support/ManagedStatic.h"
18 
19 namespace clang {
20 namespace ast_matchers {
21 namespace internal {
22 
23 bool NotUnaryOperator(const ast_type_traits::DynTypedNode &DynNode,
24  ASTMatchFinder *Finder, BoundNodesTreeBuilder *Builder,
25  ArrayRef<DynTypedMatcher> InnerMatchers);
26 
27 bool AllOfVariadicOperator(const ast_type_traits::DynTypedNode &DynNode,
28  ASTMatchFinder *Finder,
29  BoundNodesTreeBuilder *Builder,
30  ArrayRef<DynTypedMatcher> InnerMatchers);
31 
32 bool EachOfVariadicOperator(const ast_type_traits::DynTypedNode &DynNode,
33  ASTMatchFinder *Finder,
34  BoundNodesTreeBuilder *Builder,
35  ArrayRef<DynTypedMatcher> InnerMatchers);
36 
37 bool AnyOfVariadicOperator(const ast_type_traits::DynTypedNode &DynNode,
38  ASTMatchFinder *Finder,
39  BoundNodesTreeBuilder *Builder,
40  ArrayRef<DynTypedMatcher> InnerMatchers);
41 
42 
43 void BoundNodesTreeBuilder::visitMatches(Visitor *ResultVisitor) {
44  if (Bindings.empty())
45  Bindings.push_back(BoundNodesMap());
46  for (BoundNodesMap &Binding : Bindings) {
47  ResultVisitor->visitMatch(BoundNodes(Binding));
48  }
49 }
50 
51 namespace {
52 
53 typedef bool (*VariadicOperatorFunction)(
54  const ast_type_traits::DynTypedNode &DynNode, ASTMatchFinder *Finder,
55  BoundNodesTreeBuilder *Builder, ArrayRef<DynTypedMatcher> InnerMatchers);
56 
57 template <VariadicOperatorFunction Func>
58 class VariadicMatcher : public DynMatcherInterface {
59 public:
60  VariadicMatcher(std::vector<DynTypedMatcher> InnerMatchers)
61  : InnerMatchers(std::move(InnerMatchers)) {}
62 
63  bool dynMatches(const ast_type_traits::DynTypedNode &DynNode,
64  ASTMatchFinder *Finder,
65  BoundNodesTreeBuilder *Builder) const override {
66  return Func(DynNode, Finder, Builder, InnerMatchers);
67  }
68 
69 private:
70  std::vector<DynTypedMatcher> InnerMatchers;
71 };
72 
73 class IdDynMatcher : public DynMatcherInterface {
74  public:
75  IdDynMatcher(StringRef ID,
76  const IntrusiveRefCntPtr<DynMatcherInterface> &InnerMatcher)
77  : ID(ID), InnerMatcher(InnerMatcher) {}
78 
79  bool dynMatches(const ast_type_traits::DynTypedNode &DynNode,
80  ASTMatchFinder *Finder,
81  BoundNodesTreeBuilder *Builder) const override {
82  bool Result = InnerMatcher->dynMatches(DynNode, Finder, Builder);
83  if (Result) Builder->setBinding(ID, DynNode);
84  return Result;
85  }
86 
87  private:
88  const std::string ID;
89  const IntrusiveRefCntPtr<DynMatcherInterface> InnerMatcher;
90 };
91 
92 /// \brief A matcher that always returns true.
93 ///
94 /// We only ever need one instance of this matcher, so we create a global one
95 /// and reuse it to reduce the overhead of the matcher and increase the chance
96 /// of cache hits.
97 class TrueMatcherImpl : public DynMatcherInterface {
98 public:
99  TrueMatcherImpl() {
100  Retain(); // Reference count will never become zero.
101  }
102  bool dynMatches(const ast_type_traits::DynTypedNode &, ASTMatchFinder *,
103  BoundNodesTreeBuilder *) const override {
104  return true;
105  }
106 };
107 static llvm::ManagedStatic<TrueMatcherImpl> TrueMatcherInstance;
108 
109 } // namespace
110 
111 DynTypedMatcher DynTypedMatcher::constructVariadic(
112  DynTypedMatcher::VariadicOperator Op,
113  std::vector<DynTypedMatcher> InnerMatchers) {
114  assert(InnerMatchers.size() > 0 && "Array must not be empty.");
115  assert(std::all_of(InnerMatchers.begin(), InnerMatchers.end(),
116  [&InnerMatchers](const DynTypedMatcher &M) {
117  return InnerMatchers[0].canConvertTo(M.SupportedKind);
118  }) &&
119  "SupportedKind must be convertible to a common type!");
120 
121  auto SupportedKind = InnerMatchers[0].SupportedKind;
122  // We must relax the restrict kind here.
123  // The different operators might deal differently with a mismatch.
124  // Make it the same as SupportedKind, since that is the broadest type we are
125  // allowed to accept.
126  auto RestrictKind = SupportedKind;
127 
128  switch (Op) {
129  case VO_AllOf:
130  // In the case of allOf() we must pass all the checks, so making
131  // RestrictKind the most restrictive can save us time. This way we reject
132  // invalid types earlier and we can elide the kind checks inside the
133  // matcher.
134  for (auto &IM : InnerMatchers) {
136  RestrictKind, IM.RestrictKind);
137  }
138  return DynTypedMatcher(
139  SupportedKind, RestrictKind,
140  new VariadicMatcher<AllOfVariadicOperator>(std::move(InnerMatchers)));
141 
142  case VO_AnyOf:
143  return DynTypedMatcher(
144  SupportedKind, RestrictKind,
145  new VariadicMatcher<AnyOfVariadicOperator>(std::move(InnerMatchers)));
146 
147  case VO_EachOf:
148  return DynTypedMatcher(
149  SupportedKind, RestrictKind,
150  new VariadicMatcher<EachOfVariadicOperator>(std::move(InnerMatchers)));
151 
152  case VO_UnaryNot:
153  // FIXME: Implement the Not operator to take a single matcher instead of a
154  // vector.
155  return DynTypedMatcher(
156  SupportedKind, RestrictKind,
157  new VariadicMatcher<NotUnaryOperator>(std::move(InnerMatchers)));
158  }
159  llvm_unreachable("Invalid Op value.");
160 }
161 
162 DynTypedMatcher DynTypedMatcher::trueMatcher(
163  ast_type_traits::ASTNodeKind NodeKind) {
164  return DynTypedMatcher(NodeKind, NodeKind, &*TrueMatcherInstance);
165 }
166 
167 bool DynTypedMatcher::canMatchNodesOfKind(
168  ast_type_traits::ASTNodeKind Kind) const {
169  return RestrictKind.isBaseOf(Kind);
170 }
171 
172 DynTypedMatcher DynTypedMatcher::dynCastTo(
173  const ast_type_traits::ASTNodeKind Kind) const {
174  auto Copy = *this;
175  Copy.SupportedKind = Kind;
176  Copy.RestrictKind =
178  return Copy;
179 }
180 
181 bool DynTypedMatcher::matches(const ast_type_traits::DynTypedNode &DynNode,
182  ASTMatchFinder *Finder,
183  BoundNodesTreeBuilder *Builder) const {
184  if (RestrictKind.isBaseOf(DynNode.getNodeKind()) &&
185  Implementation->dynMatches(DynNode, Finder, Builder)) {
186  return true;
187  }
188  // Delete all bindings when a matcher does not match.
189  // This prevents unexpected exposure of bound nodes in unmatches
190  // branches of the match tree.
191  Builder->removeBindings([](const BoundNodesMap &) { return true; });
192  return false;
193 }
194 
195 bool DynTypedMatcher::matchesNoKindCheck(
196  const ast_type_traits::DynTypedNode &DynNode, ASTMatchFinder *Finder,
197  BoundNodesTreeBuilder *Builder) const {
198  assert(RestrictKind.isBaseOf(DynNode.getNodeKind()));
199  if (Implementation->dynMatches(DynNode, Finder, Builder)) {
200  return true;
201  }
202  // Delete all bindings when a matcher does not match.
203  // This prevents unexpected exposure of bound nodes in unmatches
204  // branches of the match tree.
205  Builder->removeBindings([](const BoundNodesMap &) { return true; });
206  return false;
207 }
208 
209 llvm::Optional<DynTypedMatcher> DynTypedMatcher::tryBind(StringRef ID) const {
210  if (!AllowBind) return llvm::None;
211  auto Result = *this;
212  Result.Implementation = new IdDynMatcher(ID, Result.Implementation);
213  return Result;
214 }
215 
216 bool DynTypedMatcher::canConvertTo(ast_type_traits::ASTNodeKind To) const {
217  const auto From = getSupportedKind();
218  auto QualKind = ast_type_traits::ASTNodeKind::getFromNodeKind<QualType>();
219  auto TypeKind = ast_type_traits::ASTNodeKind::getFromNodeKind<Type>();
220  /// Mimic the implicit conversions of Matcher<>.
221  /// - From Matcher<Type> to Matcher<QualType>
222  if (From.isSame(TypeKind) && To.isSame(QualKind)) return true;
223  /// - From Matcher<Base> to Matcher<Derived>
224  return From.isBaseOf(To);
225 }
226 
227 void BoundNodesTreeBuilder::addMatch(const BoundNodesTreeBuilder &Other) {
228  Bindings.append(Other.Bindings.begin(), Other.Bindings.end());
229 }
230 
232  ASTMatchFinder *Finder, BoundNodesTreeBuilder *Builder,
233  ArrayRef<DynTypedMatcher> InnerMatchers) {
234  if (InnerMatchers.size() != 1)
235  return false;
236 
237  // The 'unless' matcher will always discard the result:
238  // If the inner matcher doesn't match, unless returns true,
239  // but the inner matcher cannot have bound anything.
240  // If the inner matcher matches, the result is false, and
241  // any possible binding will be discarded.
242  // We still need to hand in all the bound nodes up to this
243  // point so the inner matcher can depend on bound nodes,
244  // and we need to actively discard the bound nodes, otherwise
245  // the inner matcher will reset the bound nodes if it doesn't
246  // match, but this would be inversed by 'unless'.
247  BoundNodesTreeBuilder Discard(*Builder);
248  return !InnerMatchers[0].matches(DynNode, Finder, &Discard);
249 }
250 
252  ASTMatchFinder *Finder,
253  BoundNodesTreeBuilder *Builder,
254  ArrayRef<DynTypedMatcher> InnerMatchers) {
255  // allOf leads to one matcher for each alternative in the first
256  // matcher combined with each alternative in the second matcher.
257  // Thus, we can reuse the same Builder.
258  for (const DynTypedMatcher &InnerMatcher : InnerMatchers) {
259  if (!InnerMatcher.matchesNoKindCheck(DynNode, Finder, Builder))
260  return false;
261  }
262  return true;
263 }
264 
266  ASTMatchFinder *Finder,
267  BoundNodesTreeBuilder *Builder,
268  ArrayRef<DynTypedMatcher> InnerMatchers) {
269  BoundNodesTreeBuilder Result;
270  bool Matched = false;
271  for (const DynTypedMatcher &InnerMatcher : InnerMatchers) {
272  BoundNodesTreeBuilder BuilderInner(*Builder);
273  if (InnerMatcher.matches(DynNode, Finder, &BuilderInner)) {
274  Matched = true;
275  Result.addMatch(BuilderInner);
276  }
277  }
278  *Builder = std::move(Result);
279  return Matched;
280 }
281 
283  ASTMatchFinder *Finder,
284  BoundNodesTreeBuilder *Builder,
285  ArrayRef<DynTypedMatcher> InnerMatchers) {
286  for (const DynTypedMatcher &InnerMatcher : InnerMatchers) {
287  BoundNodesTreeBuilder Result = *Builder;
288  if (InnerMatcher.matches(DynNode, Finder, &Result)) {
289  *Builder = std::move(Result);
290  return true;
291  }
292  }
293  return false;
294 }
295 
296 HasNameMatcher::HasNameMatcher(StringRef NameRef)
297  : UseUnqualifiedMatch(NameRef.find("::") == NameRef.npos), Name(NameRef) {
298  assert(!Name.empty());
299 }
300 
301 bool HasNameMatcher::matchesNodeUnqualified(const NamedDecl &Node) const {
302  assert(UseUnqualifiedMatch);
303  if (Node.getIdentifier()) {
304  // Simple name.
305  return Name == Node.getName();
306  }
307  if (Node.getDeclName()) {
308  // Name needs to be constructed.
309  llvm::SmallString<128> NodeName;
310  llvm::raw_svector_ostream OS(NodeName);
311  Node.printName(OS);
312  return Name == OS.str();
313  }
314  return false;
315 }
316 
317 bool HasNameMatcher::matchesNodeFull(const NamedDecl &Node) const {
318  llvm::SmallString<128> NodeName = StringRef("::");
319  llvm::raw_svector_ostream OS(NodeName);
320  Node.printQualifiedName(OS);
321  const StringRef FullName = OS.str();
322  const StringRef Pattern = Name;
323 
324  if (Pattern.startswith("::"))
325  return FullName == Pattern;
326 
327  return FullName.endswith(Pattern) &&
328  FullName.drop_back(Pattern.size()).endswith("::");
329 }
330 
331 bool HasNameMatcher::matchesNode(const NamedDecl &Node) const {
332  // FIXME: There is still room for improvement, but it would require copying a
333  // lot of the logic from NamedDecl::printQualifiedName(). The benchmarks do
334  // not show like that extra complexity is needed right now.
335  if (UseUnqualifiedMatch) {
336  assert(matchesNodeUnqualified(Node) == matchesNodeFull(Node));
337  return matchesNodeUnqualified(Node);
338  }
339  return matchesNodeFull(Node);
340 }
341 
342 } // end namespace internal
343 } // end namespace ast_matchers
344 } // end namespace clang
StringRef getName() const
Definition: Decl.h:168
IdentifierInfo * getIdentifier() const
Definition: Decl.h:163
bool AnyOfVariadicOperator(const ast_type_traits::DynTypedNode &DynNode, ASTMatchFinder *Finder, BoundNodesTreeBuilder *Builder, ArrayRef< DynTypedMatcher > InnerMatchers)
bool NotUnaryOperator(const ast_type_traits::DynTypedNode &DynNode, ASTMatchFinder *Finder, BoundNodesTreeBuilder *Builder, ArrayRef< DynTypedMatcher > InnerMatchers)
std::vector< DynTypedMatcher > InnerMatchers
const IntrusiveRefCntPtr< DynMatcherInterface > InnerMatcher
bool EachOfVariadicOperator(const ast_type_traits::DynTypedNode &DynNode, ASTMatchFinder *Finder, BoundNodesTreeBuilder *Builder, ArrayRef< DynTypedMatcher > InnerMatchers)
bool AllOfVariadicOperator(const ast_type_traits::DynTypedNode &DynNode, ASTMatchFinder *Finder, BoundNodesTreeBuilder *Builder, ArrayRef< DynTypedMatcher > InnerMatchers)
#define bool
Definition: stdbool.h:31
static ASTNodeKind getMostDerivedType(ASTNodeKind Kind1, ASTNodeKind Kind2)
Return the most derived type between Kind1 and Kind2.
DeclarationName getDeclName() const
Definition: Decl.h:189
The result type of a method or function.
ASTMatchFinder *const Finder
Kind
const std::string ID
void printName(raw_ostream &os) const
Definition: Decl.h:185
BoundNodesTreeBuilder BoundNodes
ast_type_traits::DynTypedNode Node
A dynamically typed AST node container.
BoundNodesTreeBuilder *const Builder
bool matches(const til::SExpr *E1, const til::SExpr *E2)