Replace push_back(Constructor(foo)) with emplace_back(foo) for non-trivial types

If the type isn't trivially moveable emplace can skip a potentially
expensive move. It also saves a couple of characters.


Call sites were found with the ASTMatcher + some semi-automated cleanup.

memberCallExpr(
    argumentCountIs(1), callee(methodDecl(hasName("push_back"))),
    on(hasType(recordDecl(has(namedDecl(hasName("emplace_back")))))),
    hasArgument(0, bindTemporaryExpr(
                       hasType(recordDecl(hasNonTrivialDestructor())),
                       has(constructExpr()))),
    unless(isInTemplateInstantiation()))

No functional change intended.

llvm-svn: 238601

2 files changed, 9 insertions, 9 deletions

diff --git a/clang/lib/ASTMatchers/ASTMatchFinder.cpp b/clang/lib/ASTMatchers/ASTMatchFinder.cpp
index c5f3063fb4f..e3b666ef42a 100644
--- a/clang/lib/ASTMatchers/ASTMatchFinder.cpp
+++ b/clang/lib/ASTMatchers/ASTMatchFinder.cpp
@@ -912,37 +912,37 @@ MatchFinder::~MatchFinder() {}
 
 void MatchFinder::addMatcher(const DeclarationMatcher &NodeMatch,
                              MatchCallback *Action) {
-  Matchers.DeclOrStmt.push_back(std::make_pair(NodeMatch, Action));
+  Matchers.DeclOrStmt.emplace_back(NodeMatch, Action);
   Matchers.AllCallbacks.push_back(Action);
 }
 
 void MatchFinder::addMatcher(const TypeMatcher &NodeMatch,
                              MatchCallback *Action) {
-  Matchers.Type.push_back(std::make_pair(NodeMatch, Action));
+  Matchers.Type.emplace_back(NodeMatch, Action);
   Matchers.AllCallbacks.push_back(Action);
 }
 
 void MatchFinder::addMatcher(const StatementMatcher &NodeMatch,
                              MatchCallback *Action) {
-  Matchers.DeclOrStmt.push_back(std::make_pair(NodeMatch, Action));
+  Matchers.DeclOrStmt.emplace_back(NodeMatch, Action);
   Matchers.AllCallbacks.push_back(Action);
 }
 
 void MatchFinder::addMatcher(const NestedNameSpecifierMatcher &NodeMatch,
                              MatchCallback *Action) {
-  Matchers.NestedNameSpecifier.push_back(std::make_pair(NodeMatch, Action));
+  Matchers.NestedNameSpecifier.emplace_back(NodeMatch, Action);
   Matchers.AllCallbacks.push_back(Action);
 }
 
 void MatchFinder::addMatcher(const NestedNameSpecifierLocMatcher &NodeMatch,
                              MatchCallback *Action) {
-  Matchers.NestedNameSpecifierLoc.push_back(std::make_pair(NodeMatch, Action));
+  Matchers.NestedNameSpecifierLoc.emplace_back(NodeMatch, Action);
   Matchers.AllCallbacks.push_back(Action);
 }
 
 void MatchFinder::addMatcher(const TypeLocMatcher &NodeMatch,
                              MatchCallback *Action) {
-  Matchers.TypeLoc.push_back(std::make_pair(NodeMatch, Action));
+  Matchers.TypeLoc.emplace_back(NodeMatch, Action);
   Matchers.AllCallbacks.push_back(Action);
 }
 
diff --git a/clang/lib/ASTMatchers/Dynamic/Diagnostics.cpp b/clang/lib/ASTMatchers/Dynamic/Diagnostics.cpp
index f6d34494dec..72f127185ef 100644
--- a/clang/lib/ASTMatchers/Dynamic/Diagnostics.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Diagnostics.cpp
@@ -14,7 +14,7 @@ namespace ast_matchers {
 namespace dynamic {
 Diagnostics::ArgStream Diagnostics::pushContextFrame(ContextType Type,
                                                      SourceRange Range) {
-  ContextStack.push_back(ContextFrame());
+  ContextStack.emplace_back();
   ContextFrame& data = ContextStack.back();
   data.Type = Type;
   data.Range = Range;
@@ -65,10 +65,10 @@ Diagnostics::ArgStream &Diagnostics::ArgStream::operator<<(const Twine &Arg) {
 
 Diagnostics::ArgStream Diagnostics::addError(const SourceRange &Range,
                                              ErrorType Error) {
-  Errors.push_back(ErrorContent());
+  Errors.emplace_back();
   ErrorContent &Last = Errors.back();
   Last.ContextStack = ContextStack;
-  Last.Messages.push_back(ErrorContent::Message());
+  Last.Messages.emplace_back();
   Last.Messages.back().Range = Range;
   Last.Messages.back().Type = Error;
   return ArgStream(&Last.Messages.back().Args);