Fix slot recording of code target patches.

This makes sure that we only record relocation slots for code target
patches that happen in marked objects. Unmarked ones might be visited
again, whereas marked ones are alive and will not be visited again.

R=ulan@chromium.org
BUG=chromium:152615,chromium:144230

Review URL: https://codereview.chromium.org/11040021

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12655 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/ic-inl.h b/src/ic-inl.h
index 779dfcd..0e41093 100644 (file)
--- a/src/ic-inl.h
+++ b/src/ic-inl.h
@@ -91,12 +91,8 @@ void IC::SetTargetAtAddress(Address address, Code* target) {
   }
 #endif
   Assembler::set_target_address_at(address, target->instruction_start());
-  if (heap->gc_state() == Heap::MARK_COMPACT &&
-      heap->mark_compact_collector()->is_compacting()) {
-    Code* host = heap->isolate()->inner_pointer_to_code_cache()->
-        GcSafeFindCodeForInnerPointer(address);
-    RelocInfo rinfo(address, RelocInfo::CODE_TARGET, 0, host);
-    heap->mark_compact_collector()->RecordRelocSlot(&rinfo, target);
+  if (heap->gc_state() == Heap::MARK_COMPACT) {
+    heap->mark_compact_collector()->RecordCodeTargetPatch(address, target);
   } else {
     heap->incremental_marking()->RecordCodeTargetPatch(address, target);
   }

diff --git a/src/mark-compact.cc b/src/mark-compact.cc
index 2704f51..015f506 100644 (file)
--- a/src/mark-compact.cc
+++ b/src/mark-compact.cc
@@ -4079,6 +4079,20 @@ void MarkCompactCollector::RecordCodeEntrySlot(Address slot, Code* target) {
 }
 
 
+void MarkCompactCollector::RecordCodeTargetPatch(Address pc, Code* target) {
+  ASSERT(heap()->gc_state() == Heap::MARK_COMPACT);
+  if (is_compacting()) {
+    Code* host = heap()->isolate()->inner_pointer_to_code_cache()->
+        GcSafeFindCodeForInnerPointer(pc);
+    MarkBit mark_bit = Marking::MarkBitFrom(host);
+    if (Marking::IsBlack(mark_bit)) {
+      RelocInfo rinfo(pc, RelocInfo::CODE_TARGET, 0, host);
+      RecordRelocSlot(&rinfo, target);
+    }
+  }
+}
+
+
 static inline SlotsBuffer::SlotType DecodeSlotType(
     SlotsBuffer::ObjectSlot slot) {
   return static_cast<SlotsBuffer::SlotType>(reinterpret_cast<intptr_t>(slot));

diff --git a/src/mark-compact.h b/src/mark-compact.h
index ac26ce8..965204e 100644 (file)
--- a/src/mark-compact.h
+++ b/src/mark-compact.h
@@ -574,6 +574,7 @@ class MarkCompactCollector {
 
   void RecordRelocSlot(RelocInfo* rinfo, Object* target);
   void RecordCodeEntrySlot(Address slot, Code* target);
+  void RecordCodeTargetPatch(Address pc, Code* target);
 
   INLINE(void RecordSlot(Object** anchor_slot, Object** slot, Object* object));