Use weak cell in monomorphic KeyedStore IC.

src/mips/macro-assembler-mips.cc

 // 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.
 
 #include <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS
 
@@ skipping 3980 matching lines @@
                               SmiCheckType smi_check_type) {
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, fail);
   }
   Label success;
   CompareMapAndBranch(obj, scratch, map, &success, ne, fail);
   bind(&success);
 }
 
 
-void MacroAssembler::DispatchMap(Register obj,
-                                 Register scratch,
-                                 Handle<Map> map,
-                                 Handle<Code> success,
-                                 SmiCheckType smi_check_type) {
+void MacroAssembler::DispatchWeakMap(Register obj, Register scratch1,
+                                     Register scratch2, Handle<WeakCell> cell,
+                                     Handle<Code> success,
+                                     SmiCheckType smi_check_type) {
   Label fail;
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, &fail);
   }
-  lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
-  Jump(success, RelocInfo::CODE_TARGET, eq, scratch, Operand(map));
+  lw(scratch1, FieldMemOperand(obj, HeapObject::kMapOffset));
+  GetWeakValue(scratch2, cell);
+  Jump(success, RelocInfo::CODE_TARGET, eq, scratch1, Operand(scratch2));
   bind(&fail);
 }
 
 
 void MacroAssembler::CheckMap(Register obj,
                               Register scratch,
                               Heap::RootListIndex index,
                               Label* fail,
                               SmiCheckType smi_check_type) {
   if (smi_check_type == DO_SMI_CHECK) {
@@ skipping 2248 matching lines @@
   }
   if (mag.shift > 0) sra(result, result, mag.shift);
   srl(at, dividend, 31);
   Addu(result, result, Operand(at));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS