Make Failure inherit from MaybeObject instead of Object.

src/heap-inl.h

 // Copyright 2006-2008 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 22 matching lines @@
 #include "v8-counters.h"
 
 namespace v8 {
 namespace internal {
 
 int Heap::MaxObjectSizeInPagedSpace() {
   return Page::kMaxHeapObjectSize;
 }
 
 
-Object* Heap::AllocateSymbol(Vector<const char> str,
-                             int chars,
-                             uint32_t hash_field) {
+MaybeObject* Heap::AllocateSymbol(Vector<const char> str,
+                                  int chars,
+                                  uint32_t hash_field) {
   unibrow::Utf8InputBuffer<> buffer(str.start(),
                                     static_cast<unsigned>(str.length()));
   return AllocateInternalSymbol(&buffer, chars, hash_field);
 }
 
 
-Object* Heap::CopyFixedArray(FixedArray* src) {
+MaybeObject* Heap::CopyFixedArray(FixedArray* src) {
   return CopyFixedArrayWithMap(src, src->map());
 }
 
 
-Object* Heap::AllocateRaw(int size_in_bytes,
-                          AllocationSpace space,
-                          AllocationSpace retry_space) {
+MaybeObject* Heap::AllocateRaw(int size_in_bytes,
+                               AllocationSpace space,
+                               AllocationSpace retry_space) {
   ASSERT(allocation_allowed_ && gc_state_ == NOT_IN_GC);
   ASSERT(space != NEW_SPACE ||
          retry_space == OLD_POINTER_SPACE ||
          retry_space == OLD_DATA_SPACE ||
          retry_space == LO_SPACE);
 #ifdef DEBUG
   if (FLAG_gc_interval >= 0 &&
       !disallow_allocation_failure_ &&
       Heap::allocation_timeout_-- <= 0) {
     return Failure::RetryAfterGC(space);
   }
   Counters::objs_since_last_full.Increment();
   Counters::objs_since_last_young.Increment();
 #endif
-  Object* result;
+  MaybeObject* result;
   if (NEW_SPACE == space) {
     result = new_space_.AllocateRaw(size_in_bytes);
     if (always_allocate() && result->IsFailure()) {
       space = retry_space;
     } else {
       return result;
     }
   }
 
   if (OLD_POINTER_SPACE == space) {
     result = old_pointer_space_->AllocateRaw(size_in_bytes);
   } else if (OLD_DATA_SPACE == space) {
     result = old_data_space_->AllocateRaw(size_in_bytes);
   } else if (CODE_SPACE == space) {
     result = code_space_->AllocateRaw(size_in_bytes);
   } else if (LO_SPACE == space) {
     result = lo_space_->AllocateRaw(size_in_bytes);
   } else if (CELL_SPACE == space) {
     result = cell_space_->AllocateRaw(size_in_bytes);
   } else {
     ASSERT(MAP_SPACE == space);
     result = map_space_->AllocateRaw(size_in_bytes);
   }
   if (result->IsFailure()) old_gen_exhausted_ = true;
   return result;
 }
 
 
-Object* Heap::NumberFromInt32(int32_t value) {
+MaybeObject* Heap::NumberFromInt32(int32_t value) {
   if (Smi::IsValid(value)) return Smi::FromInt(value);
   // Bypass NumberFromDouble to avoid various redundant checks.
   return AllocateHeapNumber(FastI2D(value));
 }
 
 
-Object* Heap::NumberFromUint32(uint32_t value) {
+MaybeObject* Heap::NumberFromUint32(uint32_t value) {
   if ((int32_t)value >= 0 && Smi::IsValid((int32_t)value)) {
     return Smi::FromInt((int32_t)value);
   }
   // Bypass NumberFromDouble to avoid various redundant checks.
   return AllocateHeapNumber(FastUI2D(value));
 }
 
 
 void Heap::FinalizeExternalString(String* string) {
   ASSERT(string->IsExternalString());
   v8::String::ExternalStringResourceBase** resource_addr =
       reinterpret_cast<v8::String::ExternalStringResourceBase**>(
           reinterpret_cast<byte*>(string) +
           ExternalString::kResourceOffset -
           kHeapObjectTag);
 
   // Dispose of the C++ object if it has not already been disposed.
   if (*resource_addr != NULL) {
     (*resource_addr)->Dispose();
   }
 
   // Clear the resource pointer in the string.
   *resource_addr = NULL;
 }
 
 
-Object* Heap::AllocateRawMap() {
+MaybeObject* Heap::AllocateRawMap() {
 #ifdef DEBUG
   Counters::objs_since_last_full.Increment();
   Counters::objs_since_last_young.Increment();
 #endif
-  Object* result = map_space_->AllocateRaw(Map::kSize);
+  MaybeObject* result = map_space_->AllocateRaw(Map::kSize);
   if (result->IsFailure()) old_gen_exhausted_ = true;
 #ifdef DEBUG
   if (!result->IsFailure()) {
     // Maps have their own alignment.
     CHECK((reinterpret_cast<intptr_t>(result) & kMapAlignmentMask) ==
           static_cast<intptr_t>(kHeapObjectTag));
   }
 #endif
   return result;
 }
 
 
-Object* Heap::AllocateRawCell() {
+MaybeObject* Heap::AllocateRawCell() {
 #ifdef DEBUG
   Counters::objs_since_last_full.Increment();
   Counters::objs_since_last_young.Increment();
 #endif
-  Object* result = cell_space_->AllocateRaw(JSGlobalPropertyCell::kSize);
+  MaybeObject* result = cell_space_->AllocateRaw(JSGlobalPropertyCell::kSize);
   if (result->IsFailure()) old_gen_exhausted_ = true;
   return result;
 }
 
 
 bool Heap::InNewSpace(Object* object) {
   bool result = new_space_.Contains(object);
   ASSERT(!result ||                  // Either not in new space
          gc_state_ != NOT_IN_GC ||   // ... or in the middle of GC
          InToSpace(object));         // ... or in to-space (where we allocate).
@@ skipping 152 matching lines @@
   if (first_word.IsForwardingAddress()) {
     *p = first_word.ToForwardingAddress();
     return;
   }
 
   // Call the slow part of scavenge object.
   return ScavengeObjectSlow(p, object);
 }
 
 
-Object* Heap::PrepareForCompare(String* str) {
+MaybeObject* Heap::PrepareForCompare(String* str) {
   // Always flatten small strings and force flattening of long strings
   // after we have accumulated a certain amount we failed to flatten.
   static const int kMaxAlwaysFlattenLength = 32;
   static const int kFlattenLongThreshold = 16*KB;
 
   const int length = str->length();
-  Object* obj = str->TryFlatten();
+  MaybeObject* obj = str->TryFlatten();
   if (length <= kMaxAlwaysFlattenLength ||
       unflattened_strings_length_ >= kFlattenLongThreshold) {
     return obj;
   }
   if (obj->IsFailure()) {
     unflattened_strings_length_ += length;
   }
   return str;
 }
 
@@ skipping 33 matching lines @@
   if (FLAG_gc_greedy) v8::internal::Heap::GarbageCollectionGreedyCheck()
 #else
 #define GC_GREEDY_CHECK() { }
 #endif
 
 
 // Calls the FUNCTION_CALL function and retries it up to three times
 // to guarantee that any allocations performed during the call will
 // succeed if there's enough memory.
 
-// Warning: Do not use the identifiers __object__ or __scope__ in a
-// call to this macro.
+// Warning: Do not use the identifiers __object__, __maybe_object__ or
+// __scope__ in a call to this macro.
 
 #define CALL_AND_RETRY(FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY)         \
   do {                                                                    \
     GC_GREEDY_CHECK();                                                    \
-    Object* __object__ = FUNCTION_CALL;                                   \
-    if (!__object__->IsFailure()) RETURN_VALUE;                           \
-    if (__object__->IsOutOfMemoryFailure()) {                             \
+    MaybeObject* __maybe_object__ = FUNCTION_CALL;                        \
+    Object* __object__ = NULL;                                            \
+    if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE;            \
+    if (__maybe_object__->IsOutOfMemory()) {                              \
       v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_0", true);\
     }                                                                     \
-    if (!__object__->IsRetryAfterGC()) RETURN_EMPTY;                      \
-    Heap::CollectGarbage(Failure::cast(__object__)->allocation_space());  \
-    __object__ = FUNCTION_CALL;                                           \
-    if (!__object__->IsFailure()) RETURN_VALUE;                           \
-    if (__object__->IsOutOfMemoryFailure()) {                             \
+    if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY;                \
+    Heap::CollectGarbage(Failure::cast(__maybe_object__)->                \
+                             allocation_space());                         \
+    __maybe_object__ = FUNCTION_CALL;                                     \
+    if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE;            \
+    if (__maybe_object__->IsOutOfMemory()) {                              \
       v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_1", true);\
     }                                                                     \
-    if (!__object__->IsRetryAfterGC()) RETURN_EMPTY;                      \
+    if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY;                \
     Counters::gc_last_resort_from_handles.Increment();                    \
     Heap::CollectAllGarbage(false);                                       \
     {                                                                     \
       AlwaysAllocateScope __scope__;                                      \
-      __object__ = FUNCTION_CALL;                                         \
+      __maybe_object__ = FUNCTION_CALL;                                   \
     }                                                                     \
-    if (!__object__->IsFailure()) RETURN_VALUE;                           \
-    if (__object__->IsOutOfMemoryFailure() ||                             \
-        __object__->IsRetryAfterGC()) {                                   \
+    if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE;            \
+    if (__maybe_object__->IsOutOfMemory() ||                              \
+        __maybe_object__->IsRetryAfterGC()) {                             \
       /* TODO(1181417): Fix this. */                                      \
       v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_2", true);\
     }                                                                     \
     RETURN_EMPTY;                                                         \
   } while (false)
 
 
 #define CALL_HEAP_FUNCTION(FUNCTION_CALL, TYPE)                \
   CALL_AND_RETRY(FUNCTION_CALL,                                \
                  return Handle<TYPE>(TYPE::cast(__object__)),  \
@@ skipping 61 matching lines @@
 
 
 void ExternalStringTable::ShrinkNewStrings(int position) {
   new_space_strings_.Rewind(position);
   Verify();
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_INL_H_