Migrate StringLengthStub to TF builtin

Bug: 
Change-Id: I58ce9a0f42dfa81c8e8affa2377c5cc0d08a35e2
Reviewed-on: https://chromium-review.googlesource.com/691714
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48222}

src/builtins/builtins-definitions.h

@@ -213,6 +213,7 @@ namespace internal {
   ASM(LoadIC_Getter_ForDeopt)                                                  \
   TFH(LoadIC_Miss, LoadWithVector)                                             \
   TFH(LoadIC_Slow, LoadWithVector)                                             \
+  TFH(LoadIC_StringLength, LoadWithVector)                                     \
   TFH(LoadIC_Uninitialized, LoadWithVector)                                    \
   TFH(StoreIC_Miss, StoreWithVector)                                           \
   ASM(StoreIC_Setter_ForDeopt)                                                 \

src/builtins/builtins-handler-gen.cc

@@ -13,6 +13,13 @@
 namespace v8 {
 namespace internal {
 
+TF_BUILTIN(LoadIC_StringLength, CodeStubAssembler) {
+  Node* value = Parameter(Descriptor::kReceiver);
+  Node* string = LoadJSValueValue(value);
+  Node* result = LoadStringLength(string);
+  Return(result);
+}
+
 TF_BUILTIN(KeyedLoadIC_IndexedString, CodeStubAssembler) {
   Node* receiver = Parameter(Descriptor::kReceiver);
   Node* index = Parameter(Descriptor::kName);

src/code-stubs.cc

@@ -339,14 +339,6 @@ TF_STUB(ElementsTransitionAndStoreStub, CodeStubAssembler) {
   }
 }
 
-// TODO(ishell): move to builtins-handler-gen.
-TF_STUB(StringLengthStub, CodeStubAssembler) {
-  Node* value = Parameter(Descriptor::kReceiver);
-  Node* string = LoadJSValueValue(value);
-  Node* result = LoadStringLength(string);
-  Return(result);
-}
-
 TF_STUB(TransitionElementsKindStub, CodeStubAssembler) {
   Node* context = Parameter(Descriptor::kContext);
   Node* object = Parameter(Descriptor::kObject);

src/code-stubs.h

@@ -47,7 +47,6 @@ class Node;
   V(ArrayNoArgumentConstructor)               \
   V(ArraySingleArgumentConstructor)           \
   V(ArrayNArgumentsConstructor)               \
-  V(StringLength)                             \
   V(InternalArrayNoArgumentConstructor)       \
   V(InternalArraySingleArgumentConstructor)   \
   V(ElementsTransitionAndStore)               \
@@ -462,14 +461,6 @@ class TurboFanCodeStub : public CodeStub {
 namespace v8 {
 namespace internal {
 
-class StringLengthStub : public TurboFanCodeStub {
- public:
-  explicit StringLengthStub(Isolate* isolate) : TurboFanCodeStub(isolate) {}
-
-  DEFINE_CALL_INTERFACE_DESCRIPTOR(LoadWithVector);
-  DEFINE_TURBOFAN_CODE_STUB(StringLength, TurboFanCodeStub);
-};
-
 class StoreInterceptorStub : public TurboFanCodeStub {
  public:
   explicit StoreInterceptorStub(Isolate* isolate) : TurboFanCodeStub(isolate) {}

src/counters.h

@@ -867,7 +867,7 @@ class RuntimeCallTimer final {
   V(LoadIC_NonReceiver)                          \
   V(LoadIC_Premonomorphic)                       \
   V(LoadIC_SlowStub)                             \
-  V(LoadIC_StringLengthStub)                     \
+  V(LoadIC_StringLength)                         \
   V(StoreIC_HandlerCacheHit_Accessor)            \
   V(StoreIC_NonReceiver)                         \
   V(StoreIC_Premonomorphic)                      \

src/ic/ic.cc

@@ -719,9 +719,8 @@ Handle<Object> LoadIC::GetMapIndependentHandler(LookupIterator* lookup) {
 
   if (receiver->IsStringWrapper() &&
       *lookup->name() == isolate()->heap()->length_string()) {
-    TRACE_HANDLER_STATS(isolate(), LoadIC_StringLengthStub);
-    StringLengthStub string_length_stub(isolate());
-    return string_length_stub.GetCode();
+    TRACE_HANDLER_STATS(isolate(), LoadIC_StringLength);
+    return BUILTIN_CODE(isolate(), LoadIC_StringLength);
   }
 
   // Use specialized code for getting prototype of functions.

test/cctest/compiler/test-run-stubs.cc

@@ -108,8 +108,7 @@ TEST(RunStringLengthStub) {
   Isolate* isolate = scope.main_isolate();
   Zone* zone = scope.main_zone();
 
-  StringLengthStub stub(isolate);
-  StubTester tester(isolate, zone, &stub);
+  StubTester tester(isolate, zone, Builtins::kLoadIC_StringLength);
 
   // Actuall call through to the stub, verifying its result.
   const char* testString = "Und das Lamm schrie HURZ!";