Use weak cell in monomorphic KeyedStore IC.

src/arm64/macro-assembler-arm64.h

 // Copyright 2013 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_ARM64_MACRO_ASSEMBLER_ARM64_H_
 #define V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
 
 #include <vector>
 
 #include "src/bailout-reason.h"
@@ skipping 1460 matching lines @@
                 Label* fail,
                 SmiCheckType smi_check_type);
 
   // As above, but the map of the object is already loaded into obj_map, and is
   // preserved.
   void CheckMap(Register obj_map,
                 Handle<Map> map,
                 Label* fail,
                 SmiCheckType smi_check_type);
 
-  // Check if the map of an object is equal to a specified map and branch to a
-  // specified target if equal. Skip the smi check if not required (object is
-  // known to be a heap object)
-  void DispatchMap(Register obj,
-                   Register scratch,
-                   Handle<Map> map,
-                   Handle<Code> success,
-                   SmiCheckType smi_check_type);
+  // Check if the map of an object is equal to a specified weak map and branch
+  // to a specified target if equal. Skip the smi check if not required
+  // (object is known to be a heap object)
+  void DispatchWeakMap(Register obj, Register scratch1, Register scratch2,
+                       Handle<WeakCell> cell, Handle<Code> success,
+                       SmiCheckType smi_check_type);
 
   // Compare the given value and the value of weak cell.
   void CmpWeakValue(Register value, Handle<WeakCell> cell, Register scratch);
 
   // Load the value of the weak cell in the value register. Branch to the given
   // miss label if the weak cell was cleared.
   void LoadWeakValue(Register value, Handle<WeakCell> cell, Label* miss);
 
   // Test the bitfield of the heap object map with mask and set the condition
   // flags. The object register is preserved.
@@ skipping 834 matching lines @@
 #error "Unsupported option"
 #define CODE_COVERAGE_STRINGIFY(x) #x
 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 #endif  // V8_ARM64_MACRO_ASSEMBLER_ARM64_H_