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

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
index 623dbc9f42c..a87f8504bfb 100644
--- a/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
+++ b/llvm/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
@@ -636,7 +636,7 @@ void PromoteMem2Reg::run() {
   // and inserting the phi nodes we marked as necessary
   //
   std::vector<RenamePassData> RenamePassWorkList;
-  RenamePassWorkList.push_back(RenamePassData(F.begin(), nullptr, Values));
+  RenamePassWorkList.emplace_back(F.begin(), nullptr, std::move(Values));
   do {
     RenamePassData RPD;
     RPD.swap(RenamePassWorkList.back());
@@ -973,7 +973,7 @@ NextIteration:
 
   for (; I != E; ++I)
     if (VisitedSuccs.insert(*I).second)
-      Worklist.push_back(RenamePassData(*I, Pred, IncomingVals));
+      Worklist.emplace_back(*I, Pred, IncomingVals);
 
   goto NextIteration;
 }