Use a WeakCell in the CallIC type vector.

src/interface-descriptors.h

 // Copyright 2014 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_CALL_INTERFACE_DESCRIPTOR_H_
 #define V8_CALL_INTERFACE_DESCRIPTOR_H_
 
 #include "src/assembler.h"
 #include "src/macro-assembler.h"
 
@@ skipping 10 matching lines @@
   V(Instanceof)                               \
   V(VectorLoadICTrampoline)                   \
   V(VectorLoadIC)                             \
   V(FastNewClosure)                           \
   V(FastNewContext)                           \
   V(ToNumber)                                 \
   V(NumberToString)                           \
   V(FastCloneShallowArray)                    \
   V(FastCloneShallowObject)                   \
   V(CreateAllocationSite)                     \
+  V(CreateWeakCell)                           \
   V(CallFunction)                             \
   V(CallFunctionWithFeedback)                 \
   V(CallFunctionWithFeedbackAndVector)        \
   V(CallConstruct)                            \
   V(RegExpConstructResult)                    \
   V(TransitionElementsKind)                   \
   V(AllocateHeapNumber)                       \
   V(ArrayConstructorConstantArgCount)         \
   V(ArrayConstructor)                         \
   V(InternalArrayConstructorConstantArgCount) \
@@ skipping 270 matching lines @@
   DECLARE_DESCRIPTOR(FastCloneShallowObjectDescriptor, CallInterfaceDescriptor)
 };
 
 
 class CreateAllocationSiteDescriptor : public CallInterfaceDescriptor {
  public:
   DECLARE_DESCRIPTOR(CreateAllocationSiteDescriptor, CallInterfaceDescriptor)
 };
 
 
+class CreateWeakCellDescriptor : public CallInterfaceDescriptor {
+ public:
+  enum ParameterIndices {
+    kVectorIndex,
+    kSlotIndex,
+    kValueIndex,
+    kParameterCount
+  };
+
+  DECLARE_DESCRIPTOR(CreateWeakCellDescriptor, CallInterfaceDescriptor)
+};
+
+
 class CallFunctionDescriptor : public CallInterfaceDescriptor {
  public:
   DECLARE_DESCRIPTOR(CallFunctionDescriptor, CallInterfaceDescriptor)
 };
 
 
 class CallFunctionWithFeedbackDescriptor : public CallInterfaceDescriptor {
  public:
   DECLARE_DESCRIPTOR(CallFunctionWithFeedbackDescriptor,
                      CallInterfaceDescriptor)
@@ skipping 186 matching lines @@
 }  // namespace v8::internal
 
 
 #if V8_TARGET_ARCH_ARM64
 #include "src/arm64/interface-descriptors-arm64.h"
 #elif V8_TARGET_ARCH_ARM
 #include "src/arm/interface-descriptors-arm.h"
 #endif
 
 #endif  // V8_CALL_INTERFACE_DESCRIPTOR_H_