diff --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html --- a/clang/docs/LibASTMatchersReference.html +++ b/clang/docs/LibASTMatchersReference.html @@ -5728,6 +5728,19 @@ +Matcher<Expr>ignoringElidableMoveConstructorCallast_matchers::Matcher<Expr> InnerMatcher +
Matches expressions that match InnerMatcher after any elidable constructor are stripped off.
+
+Example matches the entire D1 = ... (matcher = cxxOperatorCallExpr(hasArgument(1, callExpr(hasArgument(0, ignoringElidableMoveConstructorCall(ignoringParenImpCasts(callExpr())))))))
+struct H {};
+template<typename T> H B(T A);
+void f() {
+  H D1;
+  D1 = B(B(1));
+}
+
+ + Matcher<Expr>ignoringImpCastsMatcher<Expr> InnerMatcher
Matches expressions that match InnerMatcher after any implicit casts
 are stripped off.
diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -6452,6 +6452,31 @@
   return false;
 }
 
+/// Matches expressions that match InnerMatcher after any elidable constructor are stripped off.
+///
+/// Example matches the entire D1 = ... (matcher = cxxOperatorCallExpr(hasArgument(1, callExpr(hasArgument(0, ignoringElidableMoveConstructorCall(ignoringParenImpCasts(callExpr())))))))
+/// \code
+/// struct H {};
+/// template H B(T A);
+/// void f() {
+///   H D1;
+///   D1 = B(B(1));
+/// }
+/// \endcode
+AST_MATCHER_P(Expr, ignoringElidableMoveConstructorCall,
+              ast_matchers::internal::Matcher, InnerMatcher) {
+  if (const auto* cxx_construct_expr = dyn_cast(&Node)) {
+    if (cxx_construct_expr->isElidable()) {
+      if (const auto* materialize_temp = dyn_cast(
+              cxx_construct_expr->getArg(0))) {
+        return InnerMatcher.matches(*materialize_temp, Finder, Builder);
+      }
+      return InnerMatcher.matches(*cxx_construct_expr, Finder, Builder);
+    }
+  }
+  return InnerMatcher.matches(Node, Finder, Builder);
+}
+
 //----------------------------------------------------------------------------//
 // OpenMP handling.
 //----------------------------------------------------------------------------//
diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -320,6 +320,7 @@
   REGISTER_MATCHER(hasUnqualifiedDesugaredType);
   REGISTER_MATCHER(hasValueType);
   REGISTER_MATCHER(ifStmt);
+  REGISTER_MATCHER(ignoringElidableMoveConstructorCall);
   REGISTER_MATCHER(ignoringImpCasts);
   REGISTER_MATCHER(ignoringImplicit);
   REGISTER_MATCHER(ignoringParenCasts);
diff --git a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
--- a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
@@ -566,6 +566,71 @@
                                        llvm::make_unique>("x")));
 }
 
+TEST(Matcher, IgnoresElidableConstructors) {
+  StatementMatcher matcher = cxxOperatorCallExpr(
+    hasArgument(1, callExpr(hasArgument(0, 
+                                        ignoringElidableMoveConstructorCall(
+                                          ignoringParenImpCasts(expr().bind("c")))))));
+
+  EXPECT_TRUE(matchAndVerifyResultTrue(
+    "struct H {};"
+    "template H B(T A);"
+    "void f(){"
+    "H D1;"
+    "D1=B(B(1));"
+    "}"
+    , matcher, llvm::make_unique>("c")));
+
+  EXPECT_TRUE(matchAndVerifyResultTrue(
+    "struct H {};"
+    "template H B(T A);"
+    "void f(){"
+    "H D1;"
+    "D1=B(1);"
+    "}"
+    , matcher, llvm::make_unique>("c")));
+}
+
+TEST(Matcher, IgnoresElidableInReturn) {
+  auto matcher = expr(ignoringElidableMoveConstructorCall(declRefExpr()));
+
+  EXPECT_TRUE(matches(
+    "struct H{};"
+    "H f(){"
+    "H g;"
+    "return g;"
+    "}"
+    , matcher));
+
+  EXPECT_FALSE(matches(
+    "struct H{};"
+    "H f(){"
+    "return H();"
+    "}"
+    , matcher
+  ));
+}
+
+TEST(Matcher, IgnoreElidableConstructorDoesNotMatchConstructors) {
+  auto matcher = varDecl(hasInitializer(ignoringElidableMoveConstructorCall(cxxConstructExpr())));
+  EXPECT_TRUE(matches(
+    "struct H {};"
+    "void f(){"
+    "H D;"
+    "}"
+  , matcher));
+
+};
+
+TEST(Matcher, IgnoresElidableDoesNotPreventMatches) {
+  auto matcher = expr(ignoringElidableMoveConstructorCall(integerLiteral()));
+  EXPECT_TRUE(matches(
+    "void f(){"
+    "int D = 10;"
+    "}"
+  , matcher));
+}
+
 TEST(Matcher, BindTheSameNameInAlternatives) {
   StatementMatcher matcher = anyOf(
     binaryOperator(hasOperatorName("+"),