Reland "Allocation site support for monomorphic StringAdds in BinaryOps".

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index 900385240da4631d21be27f6b3a2402d68b4d999..e366e88b481f6be5ca022d6719cd72d8845404df 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -247,6 +247,28 @@ void BinaryOpICStub::GenerateAheadOfTime(Isolate* isolate,
 }
 
 
+// static
+void BinaryOpICWithAllocationSiteStub::GenerateAheadOfTime(Isolate* isolate) {
+  // Generate special versions of the stub.
+  BinaryOpIC::State::GenerateAheadOfTime(isolate, &GenerateAheadOfTime);
+}
+
+
+void BinaryOpICWithAllocationSiteStub::PrintState(StringStream* stream) {
+  state_.Print(stream);
+}
+
+
+// static
+void BinaryOpICWithAllocationSiteStub::GenerateAheadOfTime(
+    Isolate* isolate, const BinaryOpIC::State& state) {
+  if (state.CouldCreateAllocationMementos()) {
+    BinaryOpICWithAllocationSiteStub stub(state);
+    stub.GetCode(isolate);
+  }
+}
+
+
 void NewStringAddStub::PrintBaseName(StringStream* stream) {
   stream->Add("NewStringAddStub");
   if ((flags() & STRING_ADD_CHECK_BOTH) == STRING_ADD_CHECK_BOTH) {