Register dependent codes before populating deoptimization data, which can cause GC.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 0be9626683dd30cfb2e2b604eb3b3737ee03835d..9913ee3a9f593bc518ca0afb86a5423acbadbc1f 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -88,6 +88,9 @@ void LCodeGen::FinishCode(Handle<Code> code) {
   ASSERT(is_done());
   code->set_stack_slots(GetStackSlotCount());
   code->set_safepoint_table_offset(safepoints_.GetCodeOffset());
+  if (FLAG_weak_embedded_maps_in_optimized_code) {
+    RegisterDependentCodeForEmbeddedMaps(code);
+  }
   PopulateDeoptimizationData(code);
 }
 
@@ -757,6 +760,31 @@ void LCodeGen::DeoptimizeIf(Condition cc, LEnvironment* environment) {
 }
 
 
+void LCodeGen::RegisterDependentCodeForEmbeddedMaps(Handle<Code> code) {
+  ZoneList<Handle<Map> > maps(1, zone());
+  int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
+  for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
+    RelocInfo::Mode mode = it.rinfo()->rmode();
+    if (mode == RelocInfo::EMBEDDED_OBJECT &&
+        it.rinfo()->target_object()->IsMap()) {
+      Handle<Map> map(Map::cast(it.rinfo()->target_object()));
+      if (map->CanTransition()) {
+        maps.Add(map, zone());
+      }
+    }
+  }
+#ifdef VERIFY_HEAP
+  // This disables verification of weak embedded maps after full GC.
+  // AddDependentCode can cause a GC, which would observe the state where
+  // this code is not yet in the depended code lists of the embedded maps.
+  NoWeakEmbeddedMapsVerificationScope disable_verification_of_embedded_maps;
+#endif
+  for (int i = 0; i < maps.length(); i++) {
+    maps.at(i)->AddDependentCode(code);
+  }
+}
+
+
 void LCodeGen::PopulateDeoptimizationData(Handle<Code> code) {
   int length = deoptimizations_.length();
   if (length == 0) return;