Make incremental marking clear ICs.

This extends the existing clearing of ICs during GC to incremental
marking in order to prevent cross-context retention that would last
until the next non-incremental GC.

R=erik.corry@gmail.com
TEST=cctest/test-heap/IncrementalMarkingClears[Mono,Poly]morhpicIC

Review URL: https://chromiumcodereview.appspot.com/10831123

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12259 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/frames.cc

@@ -789,7 +789,7 @@ void JavaScriptFrame::PrintTop(FILE* file,
                                          ROBUST_STRING_TRAVERSAL);
               PrintF(file, " at %s:%d", *c_script_name, line);
             } else {
-              PrintF(file, "at <unknown>:%d", line);
+              PrintF(file, " at <unknown>:%d", line);
             }
           } else {
             PrintF(file, " at <unknown>:<unknown>");

src/incremental-marking.cc

@@ -175,18 +175,6 @@ class IncrementalMarkingMarkingVisitor
     table_.Register(kVisitJSRegExp, &VisitJSRegExp);
   }
 
-  static inline void VisitCodeTarget(Heap* heap, RelocInfo* rinfo) {
-    ASSERT(RelocInfo::IsCodeTarget(rinfo->rmode()));
-    Code* target = Code::GetCodeFromTargetAddress(rinfo->target_address());
-    if (FLAG_cleanup_code_caches_at_gc && target->is_inline_cache_stub()
-        && (target->ic_age() != heap->global_ic_age())) {
-      IC::Clear(rinfo->pc());
-      target = Code::GetCodeFromTargetAddress(rinfo->target_address());
-    }
-    heap->mark_compact_collector()->RecordRelocSlot(rinfo, Code::cast(target));
-    MarkObject(heap, target);
-  }
-
   static void VisitJSWeakMap(Map* map, HeapObject* object) {
     Heap* heap = map->GetHeap();
     VisitPointers(heap,

src/mark-compact.cc

@@ -64,7 +64,6 @@ MarkCompactCollector::MarkCompactCollector() :  // NOLINT
       abort_incremental_marking_(false),
       compacting_(false),
       was_marked_incrementally_(false),
-      flush_monomorphic_ics_(false),
       tracer_(NULL),
       migration_slots_buffer_(NULL),
       heap_(NULL),
@@ -768,12 +767,6 @@ void MarkCompactCollector::AbortCompaction() {
 void MarkCompactCollector::Prepare(GCTracer* tracer) {
   was_marked_incrementally_ = heap()->incremental_marking()->IsMarking();
 
-  // Monomorphic ICs are preserved when possible, but need to be flushed
-  // when they might be keeping a Context alive, or when the heap is about
-  // to be serialized.
-  flush_monomorphic_ics_ =
-      heap()->isolate()->context_exit_happened() || Serializer::enabled();
-
   // Rather than passing the tracer around we stash it in a static member
   // variable.
   tracer_ = tracer;
@@ -1078,20 +1071,6 @@ class MarkCompactMarkingVisitor
     heap->mark_compact_collector()->MarkObject(object, mark);
   }
 
-  static inline void VisitCodeTarget(Heap* heap, RelocInfo* rinfo) {
-    ASSERT(RelocInfo::IsCodeTarget(rinfo->rmode()));
-    Code* target = Code::GetCodeFromTargetAddress(rinfo->target_address());
-    if (FLAG_cleanup_code_caches_at_gc && target->is_inline_cache_stub()
-        && (target->ic_state() == MEGAMORPHIC ||
-            heap->mark_compact_collector()->flush_monomorphic_ics_ ||
-            target->ic_age() != heap->global_ic_age())) {
-      IC::Clear(rinfo->pc());
-      target = Code::GetCodeFromTargetAddress(rinfo->target_address());
-    }
-    heap->mark_compact_collector()->RecordRelocSlot(rinfo, target);
-    MarkObject(heap, target);
-  }
-
   // Mark object pointed to by p.
   INLINE(static void MarkObjectByPointer(MarkCompactCollector* collector,
                                          Object** anchor_slot,

src/mark-compact.h

@@ -612,8 +612,6 @@ class MarkCompactCollector {
 
   bool was_marked_incrementally_;
 
-  bool flush_monomorphic_ics_;
-
   // A pointer to the current stack-allocated GC tracer object during a full
   // collection (NULL before and after).
   GCTracer* tracer_;

src/objects-visiting-inl.h

@@ -208,6 +208,26 @@ void StaticMarkingVisitor<StaticVisitor>::VisitDebugTarget(
 }
 
 
+template<typename StaticVisitor>
+void StaticMarkingVisitor<StaticVisitor>::VisitCodeTarget(
+    Heap* heap, RelocInfo* rinfo) {
+  ASSERT(RelocInfo::IsCodeTarget(rinfo->rmode()));
+  Code* target = Code::GetCodeFromTargetAddress(rinfo->target_address());
+  // Monomorphic ICs are preserved when possible, but need to be flushed
+  // when they might be keeping a Context alive, or when the heap is about
+  // to be serialized.
+  if (FLAG_cleanup_code_caches_at_gc && target->is_inline_cache_stub()
+      && (target->ic_state() == MEGAMORPHIC || Serializer::enabled() ||
+          heap->isolate()->context_exit_happened() ||
+          target->ic_age() != heap->global_ic_age())) {
+    IC::Clear(rinfo->pc());
+    target = Code::GetCodeFromTargetAddress(rinfo->target_address());
+  }
+  heap->mark_compact_collector()->RecordRelocSlot(rinfo, target);
+  StaticVisitor::MarkObject(heap, target);
+}
+
+
 template<typename StaticVisitor>
 void StaticMarkingVisitor<StaticVisitor>::VisitGlobalContext(
     Map* map, HeapObject* object) {

src/objects-visiting.h

@@ -390,6 +390,7 @@ class StaticMarkingVisitor : public StaticVisitorBase {
   static inline void VisitEmbeddedPointer(Heap* heap, RelocInfo* rinfo);
   static inline void VisitGlobalPropertyCell(Heap* heap, RelocInfo* rinfo);
   static inline void VisitDebugTarget(Heap* heap, RelocInfo* rinfo);
+  static inline void VisitCodeTarget(Heap* heap, RelocInfo* rinfo);
   static inline void VisitExternalReference(RelocInfo* rinfo) { }
   static inline void VisitRuntimeEntry(RelocInfo* rinfo) { }
 

test/cctest/test-heap.cc

@@ -2081,3 +2081,148 @@ TEST(IncrementalMarkingClearsTypeFeedbackCells) {
   CHECK(cells->Cell(0)->value()->IsTheHole());
   CHECK(cells->Cell(1)->value()->IsTheHole());
 }
+
+
+static Code* FindFirstIC(Code* code, Code::Kind kind) {
+  int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
+             RelocInfo::ModeMask(RelocInfo::CONSTRUCT_CALL) |
+             RelocInfo::ModeMask(RelocInfo::CODE_TARGET_WITH_ID) |
+             RelocInfo::ModeMask(RelocInfo::CODE_TARGET_CONTEXT);
+  for (RelocIterator it(code, mask); !it.done(); it.next()) {
+    RelocInfo* info = it.rinfo();
+    Code* target = Code::GetCodeFromTargetAddress(info->target_address());
+    if (target->is_inline_cache_stub() && target->kind() == kind) {
+      return target;
+    }
+  }
+  return NULL;
+}
+
+
+TEST(IncrementalMarkingPreservesMonomorhpicIC) {
+  if (i::FLAG_always_opt) return;
+  InitializeVM();
+  v8::HandleScope scope;
+
+  // Prepare function f that contains a monomorphic IC for object
+  // originating from the same global context.
+  CompileRun("function fun() { this.x = 1; }; var obj = new fun();"
+             "function f(o) { return o.x; } f(obj); f(obj);");
+  Handle<JSFunction> f =
+      v8::Utils::OpenHandle(
+          *v8::Handle<v8::Function>::Cast(
+              v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
+
+  Code* ic_before = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
+  CHECK(ic_before->ic_state() == MONOMORPHIC);
+
+  // Fire context dispose notification.
+  v8::V8::ContextDisposedNotification();
+
+  // Go through all incremental marking steps in one swoop.
+  IncrementalMarking* marking = HEAP->incremental_marking();
+  CHECK(marking->IsStopped());
+  marking->Start();
+  CHECK(marking->IsMarking());
+  while (!marking->IsComplete()) {
+    marking->Step(MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
+  }
+  CHECK(marking->IsComplete());
+  HEAP->CollectAllGarbage(Heap::kNoGCFlags);
+
+  Code* ic_after = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
+  CHECK(ic_after->ic_state() == MONOMORPHIC);
+}
+
+
+TEST(IncrementalMarkingClearsMonomorhpicIC) {
+  if (i::FLAG_always_opt) return;
+  InitializeVM();
+  v8::HandleScope scope;
+  v8::Local<v8::Value> obj1;
+
+  {
+    LocalContext env;
+    CompileRun("function fun() { this.x = 1; }; var obj = new fun();");
+    obj1 = env->Global()->Get(v8_str("obj"));
+  }
+
+  // Prepare function f that contains a monomorphic IC for object
+  // originating from a different global context.
+  v8::Context::GetCurrent()->Global()->Set(v8_str("obj1"), obj1);
+  CompileRun("function f(o) { return o.x; } f(obj1); f(obj1);");
+  Handle<JSFunction> f =
+      v8::Utils::OpenHandle(
+          *v8::Handle<v8::Function>::Cast(
+              v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
+
+  Code* ic_before = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
+  CHECK(ic_before->ic_state() == MONOMORPHIC);
+
+  // Fire context dispose notification.
+  v8::V8::ContextDisposedNotification();
+
+  // Go through all incremental marking steps in one swoop.
+  IncrementalMarking* marking = HEAP->incremental_marking();
+  CHECK(marking->IsStopped());
+  marking->Start();
+  CHECK(marking->IsMarking());
+  while (!marking->IsComplete()) {
+    marking->Step(MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
+  }
+  CHECK(marking->IsComplete());
+  HEAP->CollectAllGarbage(Heap::kNoGCFlags);
+
+  Code* ic_after = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
+  CHECK(ic_after->ic_state() == UNINITIALIZED);
+}
+
+
+TEST(IncrementalMarkingClearsPolymorhpicIC) {
+  if (i::FLAG_always_opt) return;
+  InitializeVM();
+  v8::HandleScope scope;
+  v8::Local<v8::Value> obj1, obj2;
+
+  {
+    LocalContext env;
+    CompileRun("function fun() { this.x = 1; }; var obj = new fun();");
+    obj1 = env->Global()->Get(v8_str("obj"));
+  }
+
+  {
+    LocalContext env;
+    CompileRun("function fun() { this.x = 2; }; var obj = new fun();");
+    obj2 = env->Global()->Get(v8_str("obj"));
+  }
+
+  // Prepare function f that contains a polymorphic IC for objects
+  // originating from two different global contexts.
+  v8::Context::GetCurrent()->Global()->Set(v8_str("obj1"), obj1);
+  v8::Context::GetCurrent()->Global()->Set(v8_str("obj2"), obj2);
+  CompileRun("function f(o) { return o.x; } f(obj1); f(obj1); f(obj2);");
+  Handle<JSFunction> f =
+      v8::Utils::OpenHandle(
+          *v8::Handle<v8::Function>::Cast(
+              v8::Context::GetCurrent()->Global()->Get(v8_str("f"))));
+
+  Code* ic_before = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
+  CHECK(ic_before->ic_state() == MEGAMORPHIC);
+
+  // Fire context dispose notification.
+  v8::V8::ContextDisposedNotification();
+
+  // Go through all incremental marking steps in one swoop.
+  IncrementalMarking* marking = HEAP->incremental_marking();
+  CHECK(marking->IsStopped());
+  marking->Start();
+  CHECK(marking->IsMarking());
+  while (!marking->IsComplete()) {
+    marking->Step(MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
+  }
+  CHECK(marking->IsComplete());
+  HEAP->CollectAllGarbage(Heap::kNoGCFlags);
+
+  Code* ic_after = FindFirstIC(f->shared()->code(), Code::LOAD_IC);
+  CHECK(ic_after->ic_state() == UNINITIALIZED);
+}