Refactor elements kind conversion.

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index f1b918b4fd75a5136b795b5e7398c4e9c510215d..b4374360c60ebbbe7ceb86a6cf0a6644eb4352ae 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -415,24 +415,29 @@ bool ToBooleanStub::Types::CanBeUndetectable() const {
 }
 
 
-void FastElementsConversionStub::Generate(MacroAssembler* masm) {
-  if (to_ == FAST_ELEMENTS) {
-    if (from_ == FAST_SMI_ONLY_ELEMENTS) {
-      GenerateSmiOnlyToObject(masm, strict_mode_);
-    } else if (from_ == FAST_DOUBLE_ELEMENTS) {
-      GenerateDoubleToObject(masm, strict_mode_);
+void ElementsTransitionAndStoreStub::Generate(MacroAssembler* masm) {
+  Label fail;
+  if (!FLAG_trace_elements_transitions) {
+    if (to_ == FAST_ELEMENTS) {
+      if (from_ == FAST_SMI_ONLY_ELEMENTS) {
+        ElementsTransitionGenerator::GenerateSmiOnlyToObject(masm);
+      } else if (from_ == FAST_DOUBLE_ELEMENTS) {
+        ElementsTransitionGenerator::GenerateDoubleToObject(masm, &fail);
+      } else {
+        UNREACHABLE();
+      }
+      KeyedStoreStubCompiler::GenerateStoreFastElement(masm,
+                                                       is_jsarray_,
+                                                       FAST_ELEMENTS);
+    } else if (from_ == FAST_SMI_ONLY_ELEMENTS && to_ == FAST_DOUBLE_ELEMENTS) {
+      ElementsTransitionGenerator::GenerateSmiOnlyToDouble(masm, &fail);
+      KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(masm, is_jsarray_);
     } else {
       UNREACHABLE();
     }
-    KeyedStoreStubCompiler::GenerateStoreFastElement(masm,
-                                                     is_jsarray_,
-                                                     FAST_ELEMENTS);
-  } else if (from_ == FAST_SMI_ONLY_ELEMENTS && to_ == FAST_DOUBLE_ELEMENTS) {
-    GenerateSmiOnlyToDouble(masm, strict_mode_);
-    KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(masm, is_jsarray_);
-  } else {
-    UNREACHABLE();
   }
+  masm->bind(&fail);
+  KeyedStoreIC::GenerateRuntimeSetProperty(masm, strict_mode_);
 }
 
 } }  // namespace v8::internal