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: 238602
diff --git a/llvm/tools/llvm-pdbdump/LinePrinter.h b/llvm/tools/llvm-pdbdump/LinePrinter.h
index c2a3ab6..b985e93 100644
--- a/llvm/tools/llvm-pdbdump/LinePrinter.h
+++ b/llvm/tools/llvm-pdbdump/LinePrinter.h
@@ -41,7 +41,7 @@
   void SetFilters(std::list<Regex> &List, Iter Begin, Iter End) {
     List.clear();
     for (; Begin != End; ++Begin)
-      List.push_back(StringRef(*Begin));
+      List.emplace_back(StringRef(*Begin));
   }
 
   raw_ostream &OS;