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Use proper write barriers instead of RecordWrites when copying object elements.

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This CL brings us one step closer to untangle the runtime-gc dependency, i.e. RecordWrites should not be called from the runtime.

BUG=

Review URL: https://codereview.chromium.org/1456533002

Cr-Commit-Position: refs/heads/master@{#32074}
This commit is contained in:
hpayer 2015-11-18 01:46:24 -08:00 committed by Commit bot
parent 30d6a4deb2
commit 23bf71d706
1 changed files with 12 additions and 24 deletions
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36
src/elements.cc
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@ -136,20 +136,14 @@ void CopyObjectToObjectElements(FixedArrayBase* from_base,
FixedArray* to = FixedArray::cast(to_base);
DCHECK(IsFastSmiOrObjectElementsKind(from_kind));
DCHECK(IsFastSmiOrObjectElementsKind(to_kind));
Address to_address = to->address() + FixedArray::kHeaderSize;
Address from_address = from->address() + FixedArray::kHeaderSize;
CopyWords(reinterpret_cast<Object**>(to_address) + to_start,
reinterpret_cast<Object**>(from_address) + from_start,
static_cast<size_t>(copy_size));
if (IsFastObjectElementsKind(from_kind) &&
IsFastObjectElementsKind(to_kind)) {
Heap* heap = from->GetHeap();
if (!heap->InNewSpace(to)) {
heap->RecordWrites(to->address(),
to->OffsetOfElementAt(to_start),
copy_size);
}
heap->incremental_marking()->RecordWrites(to);
WriteBarrierMode write_barrier_mode =
(IsFastObjectElementsKind(from_kind) && IsFastObjectElementsKind(to_kind))
? UPDATE_WRITE_BARRIER
: SKIP_WRITE_BARRIER;
for (int i = 0; i < copy_size; i++) {
Object* value = from->get(from_start + i);
to->set(to_start + i, value, write_barrier_mode);
}
}
@ -160,7 +154,6 @@ static void CopyDictionaryToObjectElements(
DisallowHeapAllocation no_allocation;
SeededNumberDictionary* from = SeededNumberDictionary::cast(from_base);
int copy_size = raw_copy_size;
Heap* heap = from->GetHeap();
if (raw_copy_size < 0) {
DCHECK(raw_copy_size == ElementsAccessor::kCopyToEnd ||
raw_copy_size == ElementsAccessor::kCopyToEndAndInitializeToHole);
@ -183,24 +176,19 @@ static void CopyDictionaryToObjectElements(
if (to_start + copy_size > to_length) {
copy_size = to_length - to_start;
}
WriteBarrierMode write_barrier_mode = IsFastObjectElementsKind(to_kind)
? UPDATE_WRITE_BARRIER
: SKIP_WRITE_BARRIER;
for (int i = 0; i < copy_size; i++) {
int entry = from->FindEntry(i + from_start);
if (entry != SeededNumberDictionary::kNotFound) {
Object* value = from->ValueAt(entry);
DCHECK(!value->IsTheHole());
to->set(i + to_start, value, SKIP_WRITE_BARRIER);
to->set(i + to_start, value, write_barrier_mode);
} else {
to->set_the_hole(i + to_start);
}
}
if (IsFastObjectElementsKind(to_kind)) {
if (!heap->InNewSpace(to)) {
heap->RecordWrites(to->address(),
to->OffsetOfElementAt(to_start),
copy_size);
}
heap->incremental_marking()->RecordWrites(to);
}
}