Use mutable heapnumbers to store doubles in fields.

src/ia32/ic-ia32.cc

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 //
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@@ skipping 458 matching lines @@
   GenerateKeyedLoadReceiverCheck(
       masm, edx, eax, Map::kHasNamedInterceptor, &slow);
 
   // If the receiver is a fast-case object, check the keyed lookup
   // cache. Otherwise probe the dictionary.
   __ mov(ebx, FieldOperand(edx, JSObject::kPropertiesOffset));
   __ cmp(FieldOperand(ebx, HeapObject::kMapOffset),
          Immediate(isolate->factory()->hash_table_map()));
   __ j(equal, &probe_dictionary);
 
+  __ jmp(&slow);

[danno, 2013/05/07 15:25:29]

You should remove this.

   // The receiver's map is still in eax, compute the keyed lookup cache hash
   // based on 32 bits of the map pointer and the string hash.
   if (FLAG_debug_code) {
     __ cmp(eax, FieldOperand(edx, HeapObject::kMapOffset));
     __ Check(equal, "Map is no longer in eax.");
   }
   __ mov(ebx, eax);  // Keep the map around for later.
   __ shr(eax, KeyedLookupCache::kMapHashShift);
   __ mov(edi, FieldOperand(ecx, String::kHashFieldOffset));
   __ shr(edi, String::kHashShift);
@@ skipping 1034 matching lines @@
 
   // Do tail-call to runtime routine.
   ExternalReference ref = miss_mode == MISS_FORCE_GENERIC
       ? ExternalReference(IC_Utility(kKeyedStoreIC_MissForceGeneric),
                           masm->isolate())
       : ExternalReference(IC_Utility(kKeyedStoreIC_Miss), masm->isolate());
   __ TailCallExternalReference(ref, 3, 1);
 }
 
 
+void StoreIC::GenerateSlow(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- eax    : value
+  //  -- ecx    : key
+  //  -- edx    : receiver
+  //  -- esp[0] : return address
+  // -----------------------------------
+
+  __ pop(ebx);
+  __ push(edx);
+  __ push(ecx);
+  __ push(eax);
+  __ push(ebx);   // return address
+
+  // Do tail-call to runtime routine.
+  ExternalReference ref(IC_Utility(kStoreIC_Slow), masm->isolate());
+  __ TailCallExternalReference(ref, 3, 1);
+}
+
+
 void KeyedStoreIC::GenerateSlow(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
 
   __ pop(ebx);
   __ push(edx);
@@ skipping 129 matching lines @@
   Condition cc = (check == ENABLE_INLINED_SMI_CHECK)
       ? (*jmp_address == Assembler::kJncShortOpcode ? not_zero : zero)
       : (*jmp_address == Assembler::kJnzShortOpcode ? not_carry : carry);
   *jmp_address = static_cast<byte>(Assembler::kJccShortPrefix | cc);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32