Make Failure inherit from MaybeObject instead of Object.

src/ia32/stub-cache-ia32.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 789 matching lines @@
   }
 
   // Return the value (register eax).
   __ ret(0);
 }
 
 
 // Generate code to check that a global property cell is empty. Create
 // the property cell at compilation time if no cell exists for the
 // property.
-static Object* GenerateCheckPropertyCell(MacroAssembler* masm,
-                                         GlobalObject* global,
-                                         String* name,
-                                         Register scratch,
-                                         Label* miss) {
-  Object* probe = global->EnsurePropertyCell(name);
-  if (probe->IsFailure()) return probe;
+MUST_USE_RESULT static MaybeObject* GenerateCheckPropertyCell(
+    MacroAssembler* masm,
+    GlobalObject* global,
+    String* name,
+    Register scratch,
+    Label* miss) {
+  Object* probe;
+  { MaybeObject* maybe_probe = global->EnsurePropertyCell(name);
+    if (!maybe_probe->ToObject(&probe)) return maybe_probe;
+  }
   JSGlobalPropertyCell* cell = JSGlobalPropertyCell::cast(probe);
   ASSERT(cell->value()->IsTheHole());
   __ mov(scratch, Immediate(Handle<Object>(cell)));
   __ cmp(FieldOperand(scratch, JSGlobalPropertyCell::kValueOffset),
          Immediate(Factory::the_hole_value()));
   __ j(not_equal, miss, not_taken);
   return cell;
 }
 
 
 // Calls GenerateCheckPropertyCell for each global object in the prototype chain
 // from object to (but not including) holder.
-static Object* GenerateCheckPropertyCells(MacroAssembler* masm,
-                                          JSObject* object,
-                                          JSObject* holder,
-                                          String* name,
-                                          Register scratch,
-                                          Label* miss) {
+MUST_USE_RESULT static MaybeObject* GenerateCheckPropertyCells(
+    MacroAssembler* masm,
+    JSObject* object,
+    JSObject* holder,
+    String* name,
+    Register scratch,
+    Label* miss) {
   JSObject* current = object;
   while (current != holder) {
     if (current->IsGlobalObject()) {
-      Object* cell = GenerateCheckPropertyCell(masm,
-                                               GlobalObject::cast(current),
-                                               name,
-                                               scratch,
-                                               miss);
-      if (cell->IsFailure()) {
-        return cell;
-      }
+      // Returns a cell or a failure.
+      MaybeObject* result = GenerateCheckPropertyCell(
+          masm,
+          GlobalObject::cast(current),
+          name,
+          scratch,
+          miss);
+      if (result->IsFailure()) return t;
     }
     ASSERT(current->IsJSObject());
     current = JSObject::cast(current->GetPrototype());
   }
   return NULL;
 }
 
 
 #undef __
 #define __ ACCESS_MASM(masm())
@@ skipping 29 matching lines @@
     // Only global objects and objects that do not require access
     // checks are allowed in stubs.
     ASSERT(current->IsJSGlobalProxy() || !current->IsAccessCheckNeeded());
 
     ASSERT(current->GetPrototype()->IsJSObject());
     JSObject* prototype = JSObject::cast(current->GetPrototype());
     if (!current->HasFastProperties() &&
         !current->IsJSGlobalObject() &&
         !current->IsJSGlobalProxy()) {
       if (!name->IsSymbol()) {
-        Object* lookup_result = Heap::LookupSymbol(name);
-        if (lookup_result->IsFailure()) {
+        MaybeObject* maybe_lookup_result = Heap::LookupSymbol(name);
+        Object* lookup_result = NULL;  // Initialization to please compiler.
+        if (!maybe_lookup_result->ToObject(&lookup_result)) {
           set_failure(Failure::cast(lookup_result));
           return reg;
-        } else {
-          name = String::cast(lookup_result);
         }
+        name = String::cast(lookup_result);
       }
       ASSERT(current->property_dictionary()->FindEntry(name) ==
              StringDictionary::kNotFound);
 
       GenerateDictionaryNegativeLookup(masm(),
                                        miss,
                                        reg,
                                        name,
                                        scratch1,
                                        scratch2);
@@ skipping 56 matching lines @@
 
   // Perform security check for access to the global object.
   ASSERT(holder->IsJSGlobalProxy() || !holder->IsAccessCheckNeeded());
   if (holder->IsJSGlobalProxy()) {
     __ CheckAccessGlobalProxy(reg, scratch1, miss);
   };
 
   // If we've skipped any global objects, it's not enough to verify
   // that their maps haven't changed.  We also need to check that the
   // property cell for the property is still empty.
-  Object* result = GenerateCheckPropertyCells(masm(),
-                                              object,
-                                              holder,
-                                              name,
-                                              scratch1,
-                                              miss);
+  MaybeObject* result = GenerateCheckPropertyCells(masm(),
+                                                   object,
+                                                   holder,
+                                                   name,
+                                                   scratch1,
+                                                   miss);
   if (result->IsFailure()) set_failure(Failure::cast(result));
 
   // Return the register containing the holder.
   return reg;
 }
 
 
 void StubCompiler::GenerateLoadField(JSObject* object,
                                      JSObject* holder,
                                      Register receiver,
@@ skipping 63 matching lines @@
 
   // Do call through the api.
   ASSERT_EQ(5, ApiGetterEntryStub::kStackSpace);
   Address getter_address = v8::ToCData<Address>(callback->getter());
   ApiFunction fun(getter_address);
   ApiGetterEntryStub stub(callback_handle, &fun);
   // Emitting a stub call may try to allocate (if the code is not
   // already generated).  Do not allow the assembler to perform a
   // garbage collection but instead return the allocation failure
   // object.
-  Object* result = masm()->TryCallStub(&stub);
-  if (result->IsFailure()) {
-    *failure = Failure::cast(result);
-    return false;
+  Object* result = NULL;  // Initialization to please compiler.
+  { MaybeObject* try_call_result = masm()->TryCallStub(&stub);
+    if (!try_call_result->ToObject(&result)) {
+      *failure = Failure::cast(result);
+      return false;
+    }
   }
   __ LeaveInternalFrame();
 
   __ ret(0);
   return true;
 }
 
 
 void StubCompiler::GenerateLoadConstant(JSObject* object,
                                         JSObject* holder,
@@ skipping 214 matching lines @@
     __ cmp(FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset),
            Immediate(Handle<SharedFunctionInfo>(function->shared())));
     __ j(not_equal, miss, not_taken);
   } else {
     __ cmp(Operand(edi), Immediate(Handle<JSFunction>(function)));
     __ j(not_equal, miss, not_taken);
   }
 }
 
 
-Object* CallStubCompiler::GenerateMissBranch() {
-  Object* obj = StubCache::ComputeCallMiss(arguments().immediate(), kind_);
-  if (obj->IsFailure()) return obj;
+MaybeObject* CallStubCompiler::GenerateMissBranch() {
+  Object* obj;
+  { MaybeObject* maybe_obj =
+        StubCache::ComputeCallMiss(arguments().immediate(), kind_);
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
   __ jmp(Handle<Code>(Code::cast(obj)), RelocInfo::CODE_TARGET);
   return obj;
 }
 
 
-Object* CallStubCompiler::CompileCallField(JSObject* object,
-                                           JSObject* holder,
-                                           int index,
-                                           String* name) {
+MUST_USE_RESULT MaybeObject* CallStubCompiler::CompileCallField(
+    JSObject* object,
+    JSObject* holder,
+    int index,
+    String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
   Label miss;
 
   GenerateNameCheck(name, &miss);
@@ skipping 23 matching lines @@
   if (object->IsGlobalObject()) {
     __ mov(edx, FieldOperand(edx, GlobalObject::kGlobalReceiverOffset));
     __ mov(Operand(esp, (argc + 1) * kPointerSize), edx);
   }
 
   // Invoke the function.
   __ InvokeFunction(edi, arguments(), JUMP_FUNCTION);
 
   // Handle call cache miss.
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(FIELD, name);
 }
 
 
-Object* CallStubCompiler::CompileArrayPushCall(Object* object,
-                                               JSObject* holder,
-                                               JSGlobalPropertyCell* cell,
-                                               JSFunction* function,
-                                               String* name) {
+MaybeObject* CallStubCompiler::CompileArrayPushCall(Object* object,
+                                                    JSObject* holder,
+                                                    JSGlobalPropertyCell* cell,
+                                                    JSFunction* function,
+                                                    String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   // If object is not an array, bail out to regular call.
   if (!object->IsJSArray() || cell != NULL) return Heap::undefined_value();
@@ skipping 117 matching lines @@
       __ ret((argc + 1) * kPointerSize);
     }
 
     __ bind(&call_builtin);
     __ TailCallExternalReference(ExternalReference(Builtins::c_ArrayPush),
                                  argc + 1,
                                  1);
   }
 
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
-Object* CallStubCompiler::CompileArrayPopCall(Object* object,
-                                              JSObject* holder,
-                                              JSGlobalPropertyCell* cell,
-                                              JSFunction* function,
-                                              String* name) {
+MaybeObject* CallStubCompiler::CompileArrayPopCall(Object* object,
+                                                   JSObject* holder,
+                                                   JSGlobalPropertyCell* cell,
+                                                   JSFunction* function,
+                                                   String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   // If object is not an array, bail out to regular call.
   if (!object->IsJSArray() || cell != NULL) return Heap::undefined_value();
@@ skipping 48 matching lines @@
   __ bind(&return_undefined);
   __ mov(eax, Immediate(Factory::undefined_value()));
   __ ret((argc + 1) * kPointerSize);
 
   __ bind(&call_builtin);
   __ TailCallExternalReference(ExternalReference(Builtins::c_ArrayPop),
                                argc + 1,
                                1);
 
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
-Object* CallStubCompiler::CompileStringCharCodeAtCall(
+MaybeObject* CallStubCompiler::CompileStringCharCodeAtCall(
     Object* object,
     JSObject* holder,
     JSGlobalPropertyCell* cell,
     JSFunction* function,
     String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : function name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
@@ skipping 41 matching lines @@
   __ ret((argc + 1) * kPointerSize);
 
   ICRuntimeCallHelper call_helper;
   char_code_at_generator.GenerateSlow(masm(), call_helper);
 
   __ bind(&index_out_of_range);
   __ Set(eax, Immediate(Factory::nan_value()));
   __ ret((argc + 1) * kPointerSize);
 
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
-Object* CallStubCompiler::CompileStringCharAtCall(Object* object,
-                                                  JSObject* holder,
-                                                  JSGlobalPropertyCell* cell,
-                                                  JSFunction* function,
-                                                  String* name) {
+MaybeObject* CallStubCompiler::CompileStringCharAtCall(
+    Object* object,
+    JSObject* holder,
+    JSGlobalPropertyCell* cell,
+    JSFunction* function,
+    String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : function name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   // If object is not a string, bail out to regular call.
   if (!object->IsString() || cell != NULL) return Heap::undefined_value();
@@ skipping 39 matching lines @@
   __ ret((argc + 1) * kPointerSize);
 
   ICRuntimeCallHelper call_helper;
   char_at_generator.GenerateSlow(masm(), call_helper);
 
   __ bind(&index_out_of_range);
   __ Set(eax, Immediate(Factory::empty_string()));
   __ ret((argc + 1) * kPointerSize);
 
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
-Object* CallStubCompiler::CompileStringFromCharCodeCall(
+MaybeObject* CallStubCompiler::CompileStringFromCharCodeCall(
     Object* object,
     JSObject* holder,
     JSGlobalPropertyCell* cell,
     JSFunction* function,
     String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : function name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
@@ skipping 44 matching lines @@
   ICRuntimeCallHelper call_helper;
   char_from_code_generator.GenerateSlow(masm(), call_helper);
 
   // Tail call the full function. We do not have to patch the receiver
   // because the function makes no use of it.
   __ bind(&slow);
   __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
 
   __ bind(&miss);
   // ecx: function name.
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return (cell == NULL) ? GetCode(function) : GetCode(NORMAL, name);
 }
 
 
-Object* CallStubCompiler::CompileMathFloorCall(Object* object,
-                                               JSObject* holder,
-                                               JSGlobalPropertyCell* cell,
-                                               JSFunction* function,
-                                               String* name) {
+MaybeObject* CallStubCompiler::CompileMathFloorCall(Object* object,
+                                                    JSObject* holder,
+                                                    JSGlobalPropertyCell* cell,
+                                                    JSFunction* function,
+                                                    String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   if (!CpuFeatures::IsSupported(SSE2)) return Heap::undefined_value();
   CpuFeatures::Scope use_sse2(SSE2);
@@ skipping 92 matching lines @@
   __ mov(eax, Operand(esp, 1 * kPointerSize));
   __ ret(2 * kPointerSize);
 
   // Tail call the full function. We do not have to patch the receiver
   // because the function makes no use of it.
   __ bind(&slow);
   __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
 
   __ bind(&miss);
   // ecx: function name.
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return (cell == NULL) ? GetCode(function) : GetCode(NORMAL, name);
 }
 
 
-Object* CallStubCompiler::CompileMathAbsCall(Object* object,
-                                             JSObject* holder,
-                                             JSGlobalPropertyCell* cell,
-                                             JSFunction* function,
-                                             String* name) {
+MaybeObject* CallStubCompiler::CompileMathAbsCall(Object* object,
+                                                  JSObject* holder,
+                                                  JSGlobalPropertyCell* cell,
+                                                  JSFunction* function,
+                                                  String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   const int argc = arguments().immediate();
 
@@ skipping 70 matching lines @@
   __ mov(FieldOperand(eax, HeapNumber::kMantissaOffset), ecx);
   __ ret(2 * kPointerSize);
 
   // Tail call the full function. We do not have to patch the receiver
   // because the function makes no use of it.
   __ bind(&slow);
   __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
 
   __ bind(&miss);
   // ecx: function name.
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return (cell == NULL) ? GetCode(function) : GetCode(NORMAL, name);
 }
 
 
-Object* CallStubCompiler::CompileCallConstant(Object* object,
-                                              JSObject* holder,
-                                              JSFunction* function,
-                                              String* name,
-                                              CheckType check) {
+MaybeObject* CallStubCompiler::CompileCallConstant(Object* object,
+                                                   JSObject* holder,
+                                                   JSFunction* function,
+                                                   String* name,
+                                                   CheckType check) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   SharedFunctionInfo* function_info = function->shared();
   if (function_info->HasCustomCallGenerator()) {
     const int id = function_info->custom_call_generator_id();
-    Object* result = CompileCustomCall(
+    MaybeObject* maybe_result = CompileCustomCall(
         id, object, holder, NULL, function, name);
+    Object* result;
+    if (!maybe_result->ToObject(&result)) return maybe_result;
     // undefined means bail out to regular compiler.
     if (!result->IsUndefined()) return result;
   }
 
   Label miss_in_smi_check;
 
   GenerateNameCheck(name, &miss_in_smi_check);
 
   // Get the receiver from the stack.
   const int argc = arguments().immediate();
@@ skipping 107 matching lines @@
   } else {
     __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
   }
 
   // Handle call cache miss.
   __ bind(&miss);
   if (depth != kInvalidProtoDepth) {
     FreeSpaceForFastApiCall(masm(), eax);
   }
   __ bind(&miss_in_smi_check);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
-Object* CallStubCompiler::CompileCallInterceptor(JSObject* object,
-                                                 JSObject* holder,
-                                                 String* name) {
+MaybeObject* CallStubCompiler::CompileCallInterceptor(JSObject* object,
+                                                      JSObject* holder,
+                                                      String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
   Label miss;
 
   GenerateNameCheck(name, &miss);
@@ skipping 34 matching lines @@
     __ mov(edx, FieldOperand(edx, GlobalObject::kGlobalReceiverOffset));
     __ mov(Operand(esp, (argc + 1) * kPointerSize), edx);
   }
 
   // Invoke the function.
   __ mov(edi, eax);
   __ InvokeFunction(edi, arguments(), JUMP_FUNCTION);
 
   // Handle load cache miss.
   __ bind(&miss);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(INTERCEPTOR, name);
 }
 
 
-Object* CallStubCompiler::CompileCallGlobal(JSObject* object,
-                                            GlobalObject* holder,
-                                            JSGlobalPropertyCell* cell,
-                                            JSFunction* function,
-                                            String* name) {
+MaybeObject* CallStubCompiler::CompileCallGlobal(JSObject* object,
+                                                 GlobalObject* holder,
+                                                 JSGlobalPropertyCell* cell,
+                                                 JSFunction* function,
+                                                 String* name) {
   // ----------- S t a t e -------------
   //  -- ecx                 : name
   //  -- esp[0]              : return address
   //  -- esp[(argc - n) * 4] : arg[n] (zero-based)
   //  -- ...
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
   SharedFunctionInfo* function_info = function->shared();
   if (function_info->HasCustomCallGenerator()) {
     const int id = function_info->custom_call_generator_id();
-    Object* result = CompileCustomCall(
+    MaybeObject* maybe_result = CompileCustomCall(
         id, object, holder, cell, function, name);
+    Object* result;
+    if (!maybe_result->ToObject(&result)) return maybe_result;
     // undefined means bail out to regular compiler.
     if (!result->IsUndefined()) return result;
   }
 
   Label miss;
 
   GenerateNameCheck(name, &miss);
 
   // Get the number of arguments.
   const int argc = arguments().immediate();
@@ skipping 15 matching lines @@
   __ IncrementCounter(&Counters::call_global_inline, 1);
   ASSERT(function->is_compiled());
   Handle<Code> code(function->code());
   ParameterCount expected(function->shared()->formal_parameter_count());
   __ InvokeCode(code, expected, arguments(),
                 RelocInfo::CODE_TARGET, JUMP_FUNCTION);
 
   // Handle call cache miss.
   __ bind(&miss);
   __ IncrementCounter(&Counters::call_global_inline_miss, 1);
-  Object* obj = GenerateMissBranch();
-  if (obj->IsFailure()) return obj;
+  Object* obj;
+  { MaybeObject* maybe_obj = GenerateMissBranch();
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
 
   // Return the generated code.
   return GetCode(NORMAL, name);
 }
 
 
-Object* StoreStubCompiler::CompileStoreField(JSObject* object,
-                                             int index,
-                                             Map* transition,
-                                             String* name) {
+MaybeObject* StoreStubCompiler::CompileStoreField(JSObject* object,
+                                                  int index,
+                                                  Map* transition,
+                                                  String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : name
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   // Generate store field code.  Trashes the name register.
   GenerateStoreField(masm(),
                      object,
                      index,
                      transition,
                      edx, ecx, ebx,
                      &miss);
 
   // Handle store cache miss.
   __ bind(&miss);
   __ mov(ecx, Immediate(Handle<String>(name)));  // restore name
   Handle<Code> ic(Builtins::builtin(Builtins::StoreIC_Miss));
   __ jmp(ic, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
   return GetCode(transition == NULL ? FIELD : MAP_TRANSITION, name);
 }
 
 
-Object* StoreStubCompiler::CompileStoreCallback(JSObject* object,
-                                                AccessorInfo* callback,
-                                                String* name) {
+MaybeObject* StoreStubCompiler::CompileStoreCallback(JSObject* object,
+                                                     AccessorInfo* callback,
+                                                     String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : name
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   // Check that the object isn't a smi.
   __ test(edx, Immediate(kSmiTagMask));
@@ skipping 28 matching lines @@
   // Handle store cache miss.
   __ bind(&miss);
   Handle<Code> ic(Builtins::builtin(Builtins::StoreIC_Miss));
   __ jmp(ic, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
   return GetCode(CALLBACKS, name);
 }
 
 
-Object* StoreStubCompiler::CompileStoreInterceptor(JSObject* receiver,
-                                                   String* name) {
+MaybeObject* StoreStubCompiler::CompileStoreInterceptor(JSObject* receiver,
+                                                        String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : name
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   // Check that the object isn't a smi.
   __ test(edx, Immediate(kSmiTagMask));
@@ skipping 27 matching lines @@
   // Handle store cache miss.
   __ bind(&miss);
   Handle<Code> ic(Builtins::builtin(Builtins::StoreIC_Miss));
   __ jmp(ic, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
   return GetCode(INTERCEPTOR, name);
 }
 
 
-Object* StoreStubCompiler::CompileStoreGlobal(GlobalObject* object,
-                                              JSGlobalPropertyCell* cell,
-                                              String* name) {
+MaybeObject* StoreStubCompiler::CompileStoreGlobal(GlobalObject* object,
+                                                   JSGlobalPropertyCell* cell,
+                                                   String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : name
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   // Check that the map of the global has not changed.
   __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
@@ skipping 12 matching lines @@
   __ bind(&miss);
   __ IncrementCounter(&Counters::named_store_global_inline_miss, 1);
   Handle<Code> ic(Builtins::builtin(Builtins::StoreIC_Miss));
   __ jmp(ic, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
   return GetCode(NORMAL, name);
 }
 
 
-Object* KeyedStoreStubCompiler::CompileStoreField(JSObject* object,
-                                                  int index,
-                                                  Map* transition,
-                                                  String* name) {
+MaybeObject* KeyedStoreStubCompiler::CompileStoreField(JSObject* object,
+                                                       int index,
+                                                       Map* transition,
+                                                       String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_store_field, 1);
 
@@ skipping 13 matching lines @@
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_store_field, 1);
   Handle<Code> ic(Builtins::builtin(Builtins::KeyedStoreIC_Miss));
   __ jmp(ic, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
   return GetCode(transition == NULL ? FIELD : MAP_TRANSITION, name);
 }
 
 
-Object* LoadStubCompiler::CompileLoadNonexistent(String* name,
-                                                 JSObject* object,
-                                                 JSObject* last) {
+MaybeObject* LoadStubCompiler::CompileLoadNonexistent(String* name,
+                                                      JSObject* object,
+                                                      JSObject* last) {
   // ----------- S t a t e -------------
   //  -- eax    : receiver
   //  -- ecx    : name
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   // Check that the receiver isn't a smi.
   __ test(eax, Immediate(kSmiTagMask));
   __ j(zero, &miss, not_taken);
 
   ASSERT(last->IsGlobalObject() || last->HasFastProperties());
 
   // Check the maps of the full prototype chain. Also check that
   // global property cells up to (but not including) the last object
   // in the prototype chain are empty.
   CheckPrototypes(object, eax, last, ebx, edx, edi, name, &miss);
 
   // If the last object in the prototype chain is a global object,
   // check that the global property cell is empty.
   if (last->IsGlobalObject()) {
-    Object* cell = GenerateCheckPropertyCell(masm(),
-                                             GlobalObject::cast(last),
-                                             name,
-                                             edx,
-                                             &miss);
+    MaybeObject* cell = GenerateCheckPropertyCell(masm(),
+                                                  GlobalObject::cast(last),
+                                                  name,
+                                                  edx,
+                                                  &miss);
     if (cell->IsFailure()) {
       miss.Unuse();
       return cell;
     }
   }
 
   // Return undefined if maps of the full prototype chain are still the
   // same and no global property with this name contains a value.
   __ mov(eax, Factory::undefined_value());
   __ ret(0);
 
   __ bind(&miss);
   GenerateLoadMiss(masm(), Code::LOAD_IC);
 
   // Return the generated code.
   return GetCode(NONEXISTENT, Heap::empty_string());
 }
 
 
-Object* LoadStubCompiler::CompileLoadField(JSObject* object,
-                                           JSObject* holder,
-                                           int index,
-                                           String* name) {
+MaybeObject* LoadStubCompiler::CompileLoadField(JSObject* object,
+                                                JSObject* holder,
+                                                int index,
+                                                String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : receiver
   //  -- ecx    : name
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   GenerateLoadField(object, holder, eax, ebx, edx, edi, index, name, &miss);
   __ bind(&miss);
   GenerateLoadMiss(masm(), Code::LOAD_IC);
 
   // Return the generated code.
   return GetCode(FIELD, name);
 }
 
 
-Object* LoadStubCompiler::CompileLoadCallback(String* name,
-                                              JSObject* object,
-                                              JSObject* holder,
-                                              AccessorInfo* callback) {
+MaybeObject* LoadStubCompiler::CompileLoadCallback(String* name,
+                                                   JSObject* object,
+                                                   JSObject* holder,
+                                                   AccessorInfo* callback) {
   // ----------- S t a t e -------------
   //  -- eax    : receiver
   //  -- ecx    : name
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   Failure* failure = Failure::InternalError();
   bool success = GenerateLoadCallback(object, holder, eax, ecx, ebx, edx, edi,
                                       callback, name, &miss, &failure);
   if (!success) {
     miss.Unuse();
     return failure;
   }
 
   __ bind(&miss);
   GenerateLoadMiss(masm(), Code::LOAD_IC);
 
   // Return the generated code.
   return GetCode(CALLBACKS, name);
 }
 
 
-Object* LoadStubCompiler::CompileLoadConstant(JSObject* object,
-                                              JSObject* holder,
-                                              Object* value,
-                                              String* name) {
+MaybeObject* LoadStubCompiler::CompileLoadConstant(JSObject* object,
+                                                   JSObject* holder,
+                                                   Object* value,
+                                                   String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : receiver
   //  -- ecx    : name
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   GenerateLoadConstant(object, holder, eax, ebx, edx, edi, value, name, &miss);
   __ bind(&miss);
   GenerateLoadMiss(masm(), Code::LOAD_IC);
 
   // Return the generated code.
   return GetCode(CONSTANT_FUNCTION, name);
 }
 
 
-Object* LoadStubCompiler::CompileLoadInterceptor(JSObject* receiver,
-                                                 JSObject* holder,
-                                                 String* name) {
+MaybeObject* LoadStubCompiler::CompileLoadInterceptor(JSObject* receiver,
+                                                      JSObject* holder,
+                                                      String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : receiver
   //  -- ecx    : name
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   LookupResult lookup;
   LookupPostInterceptor(holder, name, &lookup);
 
@@ skipping 11 matching lines @@
                           &miss);
 
   __ bind(&miss);
   GenerateLoadMiss(masm(), Code::LOAD_IC);
 
   // Return the generated code.
   return GetCode(INTERCEPTOR, name);
 }
 
 
-Object* LoadStubCompiler::CompileLoadGlobal(JSObject* object,
-                                            GlobalObject* holder,
-                                            JSGlobalPropertyCell* cell,
-                                            String* name,
-                                            bool is_dont_delete) {
+MaybeObject* LoadStubCompiler::CompileLoadGlobal(JSObject* object,
+                                                 GlobalObject* holder,
+                                                 JSGlobalPropertyCell* cell,
+                                                 String* name,
+                                                 bool is_dont_delete) {
   // ----------- S t a t e -------------
   //  -- eax    : receiver
   //  -- ecx    : name
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   // If the object is the holder then we know that it's a global
   // object which can only happen for contextual loads. In this case,
   // the receiver cannot be a smi.
@@ skipping 24 matching lines @@
 
   __ bind(&miss);
   __ IncrementCounter(&Counters::named_load_global_stub_miss, 1);
   GenerateLoadMiss(masm(), Code::LOAD_IC);
 
   // Return the generated code.
   return GetCode(NORMAL, name);
 }
 
 
-Object* KeyedLoadStubCompiler::CompileLoadField(String* name,
-                                                JSObject* receiver,
-                                                JSObject* holder,
-                                                int index) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadField(String* name,
+                                                     JSObject* receiver,
+                                                     JSObject* holder,
+                                                     int index) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_field, 1);
 
   // Check that the name has not changed.
   __ cmp(Operand(eax), Immediate(Handle<String>(name)));
   __ j(not_equal, &miss, not_taken);
 
   GenerateLoadField(receiver, holder, edx, ebx, ecx, edi, index, name, &miss);
 
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_load_field, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(FIELD, name);
 }
 
 
-Object* KeyedLoadStubCompiler::CompileLoadCallback(String* name,
-                                                   JSObject* receiver,
-                                                   JSObject* holder,
-                                                   AccessorInfo* callback) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadCallback(
+    String* name,
+    JSObject* receiver,
+    JSObject* holder,
+    AccessorInfo* callback) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_callback, 1);
 
   // Check that the name has not changed.
@@ skipping 11 matching lines @@
   __ bind(&miss);
 
   __ DecrementCounter(&Counters::keyed_load_callback, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(CALLBACKS, name);
 }
 
 
-Object* KeyedLoadStubCompiler::CompileLoadConstant(String* name,
-                                                   JSObject* receiver,
-                                                   JSObject* holder,
-                                                   Object* value) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadConstant(String* name,
+                                                        JSObject* receiver,
+                                                        JSObject* holder,
+                                                        Object* value) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_constant_function, 1);
 
   // Check that the name has not changed.
   __ cmp(Operand(eax), Immediate(Handle<String>(name)));
   __ j(not_equal, &miss, not_taken);
 
   GenerateLoadConstant(receiver, holder, edx, ebx, ecx, edi,
                        value, name, &miss);
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_load_constant_function, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(CONSTANT_FUNCTION, name);
 }
 
 
-Object* KeyedLoadStubCompiler::CompileLoadInterceptor(JSObject* receiver,
-                                                      JSObject* holder,
-                                                      String* name) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadInterceptor(JSObject* receiver,
+                                                           JSObject* holder,
+                                                           String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_interceptor, 1);
 
   // Check that the name has not changed.
@@ skipping 14 matching lines @@
                           &miss);
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_load_interceptor, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(INTERCEPTOR, name);
 }
 
 
-
-
-Object* KeyedLoadStubCompiler::CompileLoadArrayLength(String* name) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadArrayLength(String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_array_length, 1);
 
   // Check that the name has not changed.
   __ cmp(Operand(eax), Immediate(Handle<String>(name)));
   __ j(not_equal, &miss, not_taken);
 
   GenerateLoadArrayLength(masm(), edx, ecx, &miss);
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_load_array_length, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(CALLBACKS, name);
 }
 
 
-Object* KeyedLoadStubCompiler::CompileLoadStringLength(String* name) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadStringLength(String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_string_length, 1);
 
   // Check that the name has not changed.
   __ cmp(Operand(eax), Immediate(Handle<String>(name)));
   __ j(not_equal, &miss, not_taken);
 
   GenerateLoadStringLength(masm(), edx, ecx, ebx, &miss);
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_load_string_length, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(CALLBACKS, name);
 }
 
 
-Object* KeyedLoadStubCompiler::CompileLoadFunctionPrototype(String* name) {
+MaybeObject* KeyedLoadStubCompiler::CompileLoadFunctionPrototype(String* name) {
   // ----------- S t a t e -------------
   //  -- eax    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   __ IncrementCounter(&Counters::keyed_load_function_prototype, 1);
 
   // Check that the name has not changed.
   __ cmp(Operand(eax), Immediate(Handle<String>(name)));
   __ j(not_equal, &miss, not_taken);
 
   GenerateLoadFunctionPrototype(masm(), edx, ecx, ebx, &miss);
   __ bind(&miss);
   __ DecrementCounter(&Counters::keyed_load_function_prototype, 1);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
   return GetCode(CALLBACKS, name);
 }
 
 
 // Specialized stub for constructing objects from functions which only have only
 // simple assignments of the form this.x = ...; in their body.
-Object* ConstructStubCompiler::CompileConstructStub(
+MaybeObject* ConstructStubCompiler::CompileConstructStub(
     SharedFunctionInfo* shared) {
   // ----------- S t a t e -------------
   //  -- eax : argc
   //  -- edi : constructor
   //  -- esp[0] : return address
   //  -- esp[4] : last argument
   // -----------------------------------
   Label generic_stub_call;
 #ifdef ENABLE_DEBUGGER_SUPPORT
   // Check to see whether there are any break points in the function code. If
@@ skipping 119 matching lines @@
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32