[heap] Use atomic marking state in all configs

Use an atomic marking state in all builds - even builds with concurrent
marking disabled. This will allow us to simplify our code a bit.

This CL starts by always using MajorMarkingState for
MarkCompactCollector::MarkingState and removing V8_ATOMIC_MARKING_STATE.

Bug: v8:12470
Change-Id: I88a65647fb2142a63b2b51fc21391c8ef1baa82d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3314864
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78241}

BUILD.bazel

@@ -44,7 +44,6 @@ config_setting(
 # v8_enable_trace_baseline_exec
 # v8_enable_trace_feedback_updates
 # v8_enable_atomic_object_field_writes
-# v8_enable_atomic_marking_state
 # v8_enable_concurrent_marking
 # v8_enable_ignition_dispatch_counting
 # v8_enable_builtins_profiling

BUILD.gn

@@ -146,11 +146,8 @@ declare_args() {
   # into relaxed atomic operations.
   v8_enable_atomic_object_field_writes = ""
 
-  # Sets -dV8_ATOMIC_MARKING_STATE
-  v8_enable_atomic_marking_state = ""
-
-  # Controls the default values of v8_enable_atomic_object_field_writes and
-  # v8_enable_concurrent_marking_state. See the default setting code below.
+  # Controls the default value of v8_enable_concurrent_marking_state. See the
+  # default setting code below.
   v8_enable_concurrent_marking = true
 
   # Sets -dV8_IGNITION_DISPATCH_COUNTING.
@@ -430,9 +427,6 @@ if (v8_enable_single_generation == "") {
 if (v8_enable_atomic_object_field_writes == "") {
   v8_enable_atomic_object_field_writes = v8_enable_concurrent_marking
 }
-if (v8_enable_atomic_marking_state == "") {
-  v8_enable_atomic_marking_state = v8_enable_concurrent_marking
-}
 if (v8_enable_third_party_heap) {
   v8_disable_write_barriers = true
   v8_enable_single_generation = true
@@ -446,8 +440,6 @@ if (v8_enable_single_generation) {
 }
 assert(!v8_enable_concurrent_marking || v8_enable_atomic_object_field_writes,
        "Concurrent marking requires atomic object field writes.")
-assert(!v8_enable_concurrent_marking || v8_enable_atomic_marking_state,
-       "Concurrent marking requires atomic marking state.")
 if (v8_enable_trace_unoptimized == "") {
   v8_enable_trace_unoptimized =
       v8_enable_trace_ignition || v8_enable_trace_baseline_exec
@@ -904,9 +896,6 @@ config("features") {
   if (v8_enable_atomic_object_field_writes) {
     defines += [ "V8_ATOMIC_OBJECT_FIELD_WRITES" ]
   }
-  if (v8_enable_atomic_marking_state) {
-    defines += [ "V8_ATOMIC_MARKING_STATE" ]
-  }
   if (v8_enable_ignition_dispatch_counting) {
     defines += [ "V8_IGNITION_DISPATCH_COUNTING" ]
   }
@@ -2201,7 +2190,6 @@ action("v8_dump_build_config") {
     "is_ubsan_vptr=$is_ubsan_vptr",
     "target_cpu=\"$target_cpu\"",
     "v8_current_cpu=\"$v8_current_cpu\"",
-    "v8_enable_atomic_marking_state=$v8_enable_atomic_marking_state",
     "v8_enable_atomic_object_field_writes=" +
         "$v8_enable_atomic_object_field_writes",
     "v8_enable_concurrent_marking=$v8_enable_concurrent_marking",

src/heap/concurrent-marking.cc

@@ -434,10 +434,6 @@ ConcurrentMarking::ConcurrentMarking(Heap* heap,
     : heap_(heap),
       marking_worklists_(marking_worklists),
       weak_objects_(weak_objects) {
-#ifndef V8_ATOMIC_MARKING_STATE
-  // Concurrent and parallel marking require atomic marking state.
-  CHECK(!FLAG_concurrent_marking && !FLAG_parallel_marking);
-#endif
 #ifndef V8_ATOMIC_OBJECT_FIELD_WRITES
   // Concurrent marking requires atomic object field writes.
   CHECK(!FLAG_concurrent_marking);

src/heap/incremental-marking.h

@@ -81,11 +81,7 @@ class V8_EXPORT_PRIVATE IncrementalMarking final {
   static constexpr size_t kEmbedderActivationThreshold = 0;
 #endif
 
-#ifdef V8_ATOMIC_MARKING_STATE
   static const AccessMode kAtomicity = AccessMode::ATOMIC;
-#else
-  static const AccessMode kAtomicity = AccessMode::NON_ATOMIC;
-#endif
 
   IncrementalMarking(Heap* heap, WeakObjects* weak_objects);
 

src/heap/mark-compact.h

@@ -444,11 +444,7 @@ class MainMarkingVisitor final
 // Collector for young and old generation.
 class MarkCompactCollector final : public MarkCompactCollectorBase {
  public:
-#ifdef V8_ATOMIC_MARKING_STATE
   using MarkingState = MajorMarkingState;
-#else
-  using MarkingState = MajorNonAtomicMarkingState;
-#endif  // V8_ATOMIC_MARKING_STATE
   using AtomicMarkingState = MajorAtomicMarkingState;
   using NonAtomicMarkingState = MajorNonAtomicMarkingState;