[ASTMatchers] New forEachOverriden matcher.

Matches methods overridden by the given method.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@274531 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 47 insertions, 0 deletions

diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index 93a0b48133..2efef57c4f 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -825,6 +825,9 @@ public:
   overridden_methods_end(const CXXMethodDecl *Method) const;
 
   unsigned overridden_methods_size(const CXXMethodDecl *Method) const;
+  typedef llvm::iterator_range<overridden_cxx_method_iterator>
+      overridden_method_range;
+  overridden_method_range overridden_methods(const CXXMethodDecl *Method) const;
 
   /// \brief Note that the given C++ \p Method overrides the given \p
   /// Overridden method.
diff --git a/include/clang/AST/DeclCXX.h b/include/clang/AST/DeclCXX.h
index a8f00cb327..66acfee60d 100644
--- a/include/clang/AST/DeclCXX.h
+++ b/include/clang/AST/DeclCXX.h
@@ -16,6 +16,7 @@
 #ifndef LLVM_CLANG_AST_DECLCXX_H
 #define LLVM_CLANG_AST_DECLCXX_H
 
+#include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTUnresolvedSet.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/Decl.h"
@@ -1829,6 +1830,8 @@ public:
   method_iterator begin_overridden_methods() const;
   method_iterator end_overridden_methods() const;
   unsigned size_overridden_methods() const;
+  typedef ASTContext::overridden_method_range overridden_method_range;
+  overridden_method_range overridden_methods() const;
 
   /// Returns the parent of this method declaration, which
   /// is the class in which this method is defined.
diff --git a/include/clang/ASTMatchers/ASTMatchers.h b/include/clang/ASTMatchers/ASTMatchers.h
index 23d2f84f67..5ba154d335 100644
--- a/include/clang/ASTMatchers/ASTMatchers.h
+++ b/include/clang/ASTMatchers/ASTMatchers.h
@@ -3809,6 +3809,47 @@ AST_MATCHER_P(CXXMethodDecl, ofClass,
           InnerMatcher.matches(*Parent, Finder, Builder));
 }
 
+/// \brief Matches each method overriden by the given method. This matcher may
+/// produce multiple matches.
+///
+/// Given
+/// \code
+///   class A { virtual void f(); };
+///   class B : public A { void f(); };
+///   class C : public B { void f(); };
+/// \endcode
+/// cxxMethodDecl(ofClass(hasName("C")),
+///               forEachOverridden(cxxMethodDecl().bind("b"))).bind("d")
+///   matches once, with "b" binding "A::f" and "d" binding "C::f" (Note
+///   that B::f is not overridden by C::f).
+///
+/// The check can produce multiple matches in case of multiple inheritance, e.g.
+/// \code
+///   class A1 { virtual void f(); };
+///   class A2 { virtual void f(); };
+///   class C : public A1, public A2 { void f(); };
+/// \endcode
+/// cxxMethodDecl(ofClass(hasName("C")),
+///               forEachOverridden(cxxMethodDecl().bind("b"))).bind("d")
+///   matches twice, once with "b" binding "A1::f" and "d" binding "C::f", and
+///   once with "b" binding "A2::f" and "d" binding "C::f".
+AST_MATCHER_P(CXXMethodDecl, forEachOverridden,
+              internal::Matcher<CXXMethodDecl>, InnerMatcher) {
+  BoundNodesTreeBuilder Result;
+  bool Matched = false;
+  for (const auto *Overridden : Node.overridden_methods()) {
+    BoundNodesTreeBuilder OverriddenBuilder(*Builder);
+    const bool OverriddenMatched =
+        InnerMatcher.matches(*Overridden, Finder, &OverriddenBuilder);
+    if (OverriddenMatched) {
+      Matched = true;
+      Result.addMatch(OverriddenBuilder);
+    }
+  }
+  *Builder = std::move(Result);
+  return Matched;
+}
+
 /// \brief Matches if the given method declaration is virtual.
 ///
 /// Given