[llvm-mca] Fix -Wpessimizing-move warnings introduced by r339923.

Reported by buildbot `clang-with-lto-ubuntu` ( build #9858 ).

llvm-svn: 339928

llvm/tools/llvm-mca/DispatchStage.cpp

@@ -126,7 +126,7 @@ llvm::Error DispatchStage::dispatch(InstRef IR) {
   // Notify listeners of the "instruction dispatched" event,
   // and move IR to the next stage.
   notifyInstructionDispatched(IR, RegisterFiles);
-  return std::move(moveToTheNextStage(IR));
+  return moveToTheNextStage(IR);
 }
 
 llvm::Error DispatchStage::cycleStart() {
@@ -148,7 +148,7 @@ bool DispatchStage::isAvailable(const InstRef &IR) const {
 
 llvm::Error DispatchStage::execute(InstRef &IR) {
   assert(canDispatch(IR) && "Cannot dispatch another instruction!");
-  return std::move(dispatch(IR));
+  return dispatch(IR);
 }
 
 #ifndef NDEBUG

llvm/tools/llvm-mca/ExecuteStage.cpp

@@ -170,7 +170,7 @@ Error ExecuteStage::execute(InstRef &IR) {
   if (IR.getInstruction()->isExecuted()) {
     notifyInstructionExecuted(IR);
     //FIXME: add a buffer of executed instructions.
-    return std::move(moveToTheNextStage(IR));
+    return moveToTheNextStage(IR);
   }
   return ErrorSuccess();
 }

llvm/tools/llvm-mca/Stage.h

@@ -69,7 +69,7 @@ public:
   /// successor stages.
   llvm::Error moveToTheNextStage(InstRef &IR) {
     assert(checkNextStage(IR) && "Next stage is not ready!");
-    return std::move(NextInSequence->execute(IR));
+    return NextInSequence->execute(IR);
   }
 
   /// Add a listener to receive callbacks during the execution of this stage.