[heap] Don't iterate the stack when starting or incrementally finalizing incremental marking.

Change-Id: I6eb3c9c6ff25a58b2c7d0d233926514606e7ff5a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1995395
Commit-Queue: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65807}

src/common/globals.h

@@ -790,6 +790,7 @@ enum VisitMode {
   VISIT_ALL_IN_SCAVENGE,
   VISIT_ALL_IN_SWEEP_NEWSPACE,
   VISIT_ONLY_STRONG,
+  VISIT_ONLY_STRONG_IGNORE_STACK,
   VISIT_FOR_SERIALIZATION,
 };
 

src/heap/heap.cc

@@ -17,6 +17,7 @@
 #include "src/builtins/accessors.h"
 #include "src/codegen/assembler-inl.h"
 #include "src/codegen/compilation-cache.h"
+#include "src/common/globals.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer/deoptimizer.h"
 #include "src/execution/microtask-queue.h"
@@ -4361,8 +4362,10 @@ void Heap::IterateStrongRoots(RootVisitor* v, VisitMode mode) {
 
   isolate_->bootstrapper()->Iterate(v);
   v->Synchronize(VisitorSynchronization::kBootstrapper);
-  isolate_->Iterate(v);
-  v->Synchronize(VisitorSynchronization::kTop);
+  if (mode != VISIT_ONLY_STRONG_IGNORE_STACK) {
+    isolate_->Iterate(v);
+    v->Synchronize(VisitorSynchronization::kTop);
+  }
   Relocatable::Iterate(isolate_, v);
   v->Synchronize(VisitorSynchronization::kRelocatable);
   isolate_->debug()->Iterate(v);
@@ -4393,6 +4396,7 @@ void Heap::IterateStrongRoots(RootVisitor* v, VisitMode mode) {
       // global handles need to be added manually.
       break;
     case VISIT_ONLY_STRONG:
+    case VISIT_ONLY_STRONG_IGNORE_STACK:
       isolate_->global_handles()->IterateStrongRoots(v);
       break;
     case VISIT_ALL_IN_SCAVENGE:

src/heap/incremental-marking.cc

@@ -336,9 +336,7 @@ void IncrementalMarking::StartMarking() {
 
   StartBlackAllocation();
 
-  // Mark strong roots grey.
-  IncrementalMarkingRootMarkingVisitor visitor(this);
-  heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG);
+  MarkRoots();
 
   if (FLAG_concurrent_marking && !heap_->IsTearingDown()) {
     heap_->concurrent_marking()->ScheduleTasks();
@@ -413,7 +411,7 @@ void IncrementalMarking::MarkRoots() {
   DCHECK(IsMarking());
 
   IncrementalMarkingRootMarkingVisitor visitor(this);
-  heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG);
+  heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG_IGNORE_STACK);
 }
 
 bool IncrementalMarking::ShouldRetainMap(Map map, int age) {