Simplified large object allocation strategy.

src/heap.cc

 // Copyright 2012 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 5335 matching lines @@
 template
 MaybeObject* Heap::AllocateInternalizedStringImpl<false>(
     Vector<const char>, int, uint32_t);
 
 
 MaybeObject* Heap::AllocateRawOneByteString(int length,
                                             PretenureFlag pretenure) {
   if (length < 0 || length > SeqOneByteString::kMaxLength) {
     return Failure::OutOfMemoryException(0xb);
   }
 

[Michael Starzinger, 2013/07/22 19:27:50]

nit: Let's drop this empty new-line for consistency.

[Hannes Payer (out of office), 2013/07/23 20:00:51]

Done.

   int size = SeqOneByteString::SizeFor(length);
   ASSERT(size <= SeqOneByteString::kMaxSize);
 

[Michael Starzinger, 2013/07/22 19:27:50]

nit: Let's drop this empty new-line for consistency.

[Hannes Payer (out of office), 2013/07/23 20:00:51]

Done.

   AllocationSpace space = (pretenure == TENURED) ? OLD_DATA_SPACE : NEW_SPACE;
   AllocationSpace retry_space = OLD_DATA_SPACE;
 
-  if (space == NEW_SPACE) {
-    if (size > kMaxObjectSizeInNewSpace) {
-      // Allocate in large object space, retry space will be ignored.
-      space = LO_SPACE;
-    } else if (size > Page::kMaxNonCodeHeapObjectSize) {
-      // Allocate in new space, retry in large object space.
-      retry_space = LO_SPACE;
-    }
-  } else if (space == OLD_DATA_SPACE &&
-             size > Page::kMaxNonCodeHeapObjectSize) {
+  if (size > Page::kMaxNonCodeHeapObjectSize) {
+    // Allocate in large object space, retry space will be ignored.
     space = LO_SPACE;
   }
+
   Object* result;
   { MaybeObject* maybe_result = AllocateRaw(size, space, retry_space);
     if (!maybe_result->ToObject(&result)) return maybe_result;
   }
 
   // Partially initialize the object.
   HeapObject::cast(result)->set_map_no_write_barrier(ascii_string_map());
   String::cast(result)->set_length(length);
   String::cast(result)->set_hash_field(String::kEmptyHashField);
   ASSERT_EQ(size, HeapObject::cast(result)->Size());
 
   return result;
 }
 
 
 MaybeObject* Heap::AllocateRawTwoByteString(int length,
                                             PretenureFlag pretenure) {
   if (length < 0 || length > SeqTwoByteString::kMaxLength) {
     return Failure::OutOfMemoryException(0xc);
   }
   int size = SeqTwoByteString::SizeFor(length);
   ASSERT(size <= SeqTwoByteString::kMaxSize);
   AllocationSpace space = (pretenure == TENURED) ? OLD_DATA_SPACE : NEW_SPACE;
   AllocationSpace retry_space = OLD_DATA_SPACE;
 
-  if (space == NEW_SPACE) {
-    if (size > kMaxObjectSizeInNewSpace) {
-      // Allocate in large object space, retry space will be ignored.
-      space = LO_SPACE;
-    } else if (size > Page::kMaxNonCodeHeapObjectSize) {
-      // Allocate in new space, retry in large object space.
-      retry_space = LO_SPACE;
-    }
-  } else if (space == OLD_DATA_SPACE &&
-             size > Page::kMaxNonCodeHeapObjectSize) {
+  if (size > Page::kMaxNonCodeHeapObjectSize) {
+    // Allocate in large object space, retry space will be ignored.
     space = LO_SPACE;
   }
+
   Object* result;
   { MaybeObject* maybe_result = AllocateRaw(size, space, retry_space);
     if (!maybe_result->ToObject(&result)) return maybe_result;
   }
 
   // Partially initialize the object.
   HeapObject::cast(result)->set_map_no_write_barrier(string_map());
   String::cast(result)->set_length(length);
   String::cast(result)->set_hash_field(String::kEmptyHashField);
   ASSERT_EQ(size, HeapObject::cast(result)->Size());
@@ skipping 53 matching lines @@
 
 MaybeObject* Heap::AllocateRawFixedArray(int length) {
   if (length < 0 || length > FixedArray::kMaxLength) {
     return Failure::OutOfMemoryException(0xd);
   }
   ASSERT(length > 0);
   // Use the general function if we're forced to always allocate.
   if (always_allocate()) return AllocateFixedArray(length, TENURED);
   // Allocate the raw data for a fixed array.
   int size = FixedArray::SizeFor(length);
-  return size <= kMaxObjectSizeInNewSpace
+  return size <= Page::kMaxNonCodeHeapObjectSize
       ? new_space_.AllocateRaw(size)
       : lo_space_->AllocateRaw(size, NOT_EXECUTABLE);
 }
 
 
 MaybeObject* Heap::CopyFixedArrayWithMap(FixedArray* src, Map* map) {
   int len = src->length();
   Object* obj;
   { MaybeObject* maybe_obj = AllocateRawFixedArray(len);
     if (!maybe_obj->ToObject(&obj)) return maybe_obj;
@@ skipping 50 matching lines @@
   ASSERT(!InNewSpace(undefined_value()));
   MemsetPointer(array->data_start(), undefined_value(), length);
   return result;
 }
 
 
 MaybeObject* Heap::AllocateRawFixedArray(int length, PretenureFlag pretenure) {
   if (length < 0 || length > FixedArray::kMaxLength) {
     return Failure::OutOfMemoryException(0xe);
   }
 

[Michael Starzinger, 2013/07/22 19:27:50]

nit: Let's drop this empty new-line for consistency.

[Hannes Payer (out of office), 2013/07/23 20:00:51]

Done.

+  int size = FixedArray::SizeFor(length);
   AllocationSpace space =
       (pretenure == TENURED) ? OLD_POINTER_SPACE : NEW_SPACE;
-  int size = FixedArray::SizeFor(length);
-  if (space == NEW_SPACE && size > kMaxObjectSizeInNewSpace) {
-    // Too big for new space.
-    space = LO_SPACE;
-  } else if (space == OLD_POINTER_SPACE &&
-             size > Page::kMaxNonCodeHeapObjectSize) {
-    // Too big for old pointer space.
+  AllocationSpace retry_space = OLD_POINTER_SPACE;
+
+  if (size > Page::kMaxNonCodeHeapObjectSize) {
+    // Allocate in large object space, retry space will be ignored.
     space = LO_SPACE;
   }
 
-  AllocationSpace retry_space =
-      (size <= Page::kMaxNonCodeHeapObjectSize) ? OLD_POINTER_SPACE : LO_SPACE;
-
   return AllocateRaw(size, space, retry_space);
 }
 
 
 MUST_USE_RESULT static MaybeObject* AllocateFixedArrayWithFiller(
     Heap* heap,
     int length,
     PretenureFlag pretenure,
     Object* filler) {
   ASSERT(length >= 0);
@@ skipping 97 matching lines @@
   elements->set_length(length);
   return elements;
 }
 
 
 MaybeObject* Heap::AllocateRawFixedDoubleArray(int length,
                                                PretenureFlag pretenure) {
   if (length < 0 || length > FixedDoubleArray::kMaxLength) {
     return Failure::OutOfMemoryException(0xf);
   }
 

[Michael Starzinger, 2013/07/22 19:27:50]

nit: Let's drop this empty new-line for consistency.

[Hannes Payer (out of office), 2013/07/23 20:00:51]

Done.

   AllocationSpace space =
       (pretenure == TENURED) ? OLD_DATA_SPACE : NEW_SPACE;

[Michael Starzinger, 2013/07/22 19:27:50]

nit: Should fit into one line.

[Hannes Payer (out of office), 2013/07/23 20:00:51]

Done.

+  AllocationSpace retry_space = OLD_DATA_SPACE;
+
   int size = FixedDoubleArray::SizeFor(length);

[Michael Starzinger, 2013/07/22 19:27:50]

nit: Let's move this line (i.e. the size calculation) to before the assignment
of "space" for consistency.

[Hannes Payer (out of office), 2013/07/23 20:00:51]

Done.

 
 #ifndef V8_HOST_ARCH_64_BIT
   size += kPointerSize;
 #endif
 
-  if (space == NEW_SPACE && size > kMaxObjectSizeInNewSpace) {
-    // Too big for new space.
-    space = LO_SPACE;
-  } else if (space == OLD_DATA_SPACE &&
-             size > Page::kMaxNonCodeHeapObjectSize) {
-    // Too big for old data space.
+  if (size > Page::kMaxNonCodeHeapObjectSize) {
+    // Allocate in large object space, retry space will be ignored.
     space = LO_SPACE;
   }
 
-  AllocationSpace retry_space =
-      (size <= Page::kMaxNonCodeHeapObjectSize) ? OLD_DATA_SPACE : LO_SPACE;
-
   HeapObject* object;
   { MaybeObject* maybe_object = AllocateRaw(size, space, retry_space);
     if (!maybe_object->To<HeapObject>(&object)) return maybe_object;
   }
 
   return EnsureDoubleAligned(this, object, size);
 }
 
 
 MaybeObject* Heap::AllocateHashTable(int length, PretenureFlag pretenure) {
@@ skipping 2455 matching lines @@
   if (FLAG_parallel_recompilation) {
     heap_->relocation_mutex_->Lock();
 #ifdef DEBUG
     heap_->relocation_mutex_locked_by_optimizer_thread_ =
         heap_->isolate()->optimizing_compiler_thread()->IsOptimizerThread();
 #endif  // DEBUG
   }
 }
 
 } }  // namespace v8::internal