[runtime] Implement %_ToLength via ToLengthStub.

src/code-stubs.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_CODE_STUBS_H_
 #define V8_CODE_STUBS_H_
 
 #include "src/allocation.h"
 #include "src/assembler.h"
 #include "src/codegen.h"
@@ skipping 34 matching lines @@
   V(ProfileEntryHook)                       \
   V(RecordWrite)                            \
   V(RegExpExec)                             \
   V(StoreArrayLiteralElement)               \
   V(StoreBufferOverflow)                    \
   V(StoreElement)                           \
   V(StringCompare)                          \
   V(StubFailureTrampoline)                  \
   V(SubString)                              \
   V(ToNumber)                               \
+  V(ToLength)                               \
   V(ToString)                               \
   V(ToObject)                               \
   V(VectorStoreICTrampoline)                \
   V(VectorKeyedStoreICTrampoline)           \
   V(VectorStoreIC)                          \
   V(VectorKeyedStoreIC)                     \
   /* HydrogenCodeStubs */                   \
   V(AllocateHeapNumber)                     \
   V(AllocateInNewSpace)                     \
   V(ArrayNArgumentsConstructor)             \
@@ skipping 3004 matching lines @@
 
 class ToNumberStub final : public PlatformCodeStub {
  public:
   explicit ToNumberStub(Isolate* isolate) : PlatformCodeStub(isolate) {}
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(ToNumber);
   DEFINE_PLATFORM_CODE_STUB(ToNumber, PlatformCodeStub);
 };
 
 
+class ToLengthStub final : public PlatformCodeStub {
+ public:
+  explicit ToLengthStub(Isolate* isolate) : PlatformCodeStub(isolate) {}
+
+  DEFINE_CALL_INTERFACE_DESCRIPTOR(ToLength);
+  DEFINE_PLATFORM_CODE_STUB(ToLength, PlatformCodeStub);
+};
+
+
 class ToStringStub final : public PlatformCodeStub {
  public:
   explicit ToStringStub(Isolate* isolate) : PlatformCodeStub(isolate) {}
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(ToString);
   DEFINE_PLATFORM_CODE_STUB(ToString, PlatformCodeStub);
 };
 
 
 class ToObjectStub final : public HydrogenCodeStub {
@@ skipping 20 matching lines @@
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 
 extern Representation RepresentationFromType(Type* type);
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODE_STUBS_H_