Revert "cppgc: Get AgeTableTest compiling when young generation is en…

…abled"

This reverts commit d13ce73.

Reason for revert: blocks V8 roll due to blink_heap_unittests failures:
https://crrev.com/c/4562338

Original change's description:
> cppgc: Get AgeTableTest compiling when young generation is enabled
>
> age-table-unittest.cc is gated behind cppgc_enable_young_generation in
> test/unittests/BUILD.gn. Root BUILD.gn implemented a dependency where
> cppgc_enable_young_generation was set to true when the caged heap is
> enabled, but that dependency was not propagating to the tests. This CL
> moves the caged heap flag and the dependency to v8.gni so that it's
> consistent throughout the source tree.
>
> That change exposed a compile error in age-table-unittest.cc due to the
> non-stack-allocated test fixture having a member of stack-allocated type
> subtle::DisallowGarbageCollectionScope. The fix is for each test to
> declare its own DisallowGarbageCollectionScope instead.
>
> Bug: chromium:1029379, chromium:1434388
> Change-Id: If3d4f8f124585f4c74637c6cf8073cdbe6a6b5a9
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4548686
> Commit-Queue: Kevin Babbitt <kbabbitt@microsoft.com>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#87808}

Bug: chromium:1029379, chromium:1434388
Change-Id: Ie64885187bdd09c193eb0b12ffbffc1b0cbd8992
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4562958
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#87844}

BUILD.gn

@@ -300,6 +300,11 @@ declare_args() {
       v8_current_cpu == "arm64" &&
       (target_is_simulator || arm_control_flow_integrity != "none")
 
+  # Enable heap reservation of size 4GB. Only possible for 64bit archs.
+  cppgc_enable_caged_heap =
+      v8_current_cpu == "x64" || v8_current_cpu == "arm64" ||
+      v8_current_cpu == "loong64" || v8_current_cpu == "riscv64"
+
   # Enables additional heap verification phases and checks.
   cppgc_enable_verify_heap = ""
 
@@ -889,6 +894,9 @@ if (cppgc_enable_object_names) {
 if (cppgc_enable_caged_heap) {
   enabled_external_cppgc_defines += [ "CPPGC_CAGED_HEAP" ]
 
+  # Always enable young generation compile time flag if caged heap is enabled.
+  cppgc_enable_young_generation = true
+
   # Pointer compression regresses binary size on Fuchsia by about 300K.
   # However, the change improves Oilpan memory by 15-20% (2-4% of PMF),
   # which is beneficial for memory-impoverished platforms.

gni/v8.gni

@@ -101,11 +101,6 @@ declare_args() {
   # Enable object names in cppgc for debug purposes.
   cppgc_enable_object_names = false
 
-  # Enable heap reservation of size 4GB. Only possible for 64bit archs.
-  cppgc_enable_caged_heap =
-      v8_current_cpu == "x64" || v8_current_cpu == "arm64" ||
-      v8_current_cpu == "loong64" || v8_current_cpu == "riscv64"
-
   # Enable young generation in cppgc.
   cppgc_enable_young_generation = false
 
@@ -197,11 +192,6 @@ v8_path_prefix = get_path_info("../", "abspath")
 
 v8_inspector_js_protocol = v8_path_prefix + "/include/js_protocol.pdl"
 
-if (cppgc_enable_caged_heap) {
-  # Always enable young generation compile time flag if caged heap is enabled.
-  cppgc_enable_young_generation = true
-}
-
 ###############################################################################
 # Templates
 #

test/unittests/heap/cppgc/age-table-unittest.cc

@@ -22,7 +22,9 @@ class AgeTableTest : public testing::TestWithHeap {
   using AdjacentCardsPolicy = AgeTable::AdjacentCardsPolicy;
   static constexpr auto kCardSizeInBytes = AgeTable::kCardSizeInBytes;
 
-  AgeTableTest() : age_table_(CagedHeapLocalData::Get().age_table) {}
+  AgeTableTest()
+      : disallow_gc_(GetHeapHandle()),
+        age_table_(CagedHeapLocalData::Get().age_table) {}
 
   ~AgeTableTest() override { age_table_.ResetForTesting(); }
 
@@ -74,14 +76,14 @@ class AgeTableTest : public testing::TestWithHeap {
   }
 
  private:
+  subtle::DisallowGarbageCollectionScope disallow_gc_;
   std::vector<std::unique_ptr<BasePage, void (*)(BasePage*)>> allocated_pages_;
   AgeTable& age_table_;
 };
 
 }  // namespace
 
 TEST_F(AgeTableTest, SetAgeForNormalPage) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   auto* page = AllocateNormalPage();
   // By default, everything is old.
   AssertAgeForAddressRange(page->PayloadStart(), page->PayloadEnd(), Age::kOld);
@@ -94,7 +96,6 @@ TEST_F(AgeTableTest, SetAgeForNormalPage) {
 }
 
 TEST_F(AgeTableTest, SetAgeForLargePage) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   auto* page = AllocateLargePage();
   // By default, everything is old.
   AssertAgeForAddressRange(page->PayloadStart(), page->PayloadEnd(), Age::kOld);
@@ -107,7 +108,6 @@ TEST_F(AgeTableTest, SetAgeForLargePage) {
 }
 
 TEST_F(AgeTableTest, SetAgeForSingleCardWithUnalignedAddresses) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   auto* page = AllocateNormalPage();
   Address object_begin = reinterpret_cast<Address>(
       RoundUp(reinterpret_cast<uintptr_t>(page->PayloadStart()),
@@ -128,7 +128,6 @@ TEST_F(AgeTableTest, SetAgeForSingleCardWithUnalignedAddresses) {
 }
 
 TEST_F(AgeTableTest, SetAgeForSingleCardWithAlignedAddresses) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   auto* page = AllocateNormalPage();
   Address object_begin = reinterpret_cast<Address>(RoundUp(
       reinterpret_cast<uintptr_t>(page->PayloadStart()), kCardSizeInBytes));
@@ -145,7 +144,6 @@ TEST_F(AgeTableTest, SetAgeForSingleCardWithAlignedAddresses) {
 }
 
 TEST_F(AgeTableTest, SetAgeForSingleCardWithAlignedBeginButUnalignedEnd) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   auto* page = AllocateNormalPage();
   Address object_begin = reinterpret_cast<Address>(RoundUp(
       reinterpret_cast<uintptr_t>(page->PayloadStart()), kCardSizeInBytes));
@@ -162,7 +160,6 @@ TEST_F(AgeTableTest, SetAgeForSingleCardWithAlignedBeginButUnalignedEnd) {
 }
 
 TEST_F(AgeTableTest, SetAgeForMultipleCardsWithUnalignedAddresses) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   static constexpr size_t kNumberOfCards = 4;
   auto* page = AllocateNormalPage();
   Address object_begin = reinterpret_cast<Address>(
@@ -182,7 +179,6 @@ TEST_F(AgeTableTest, SetAgeForMultipleCardsWithUnalignedAddresses) {
 }
 
 TEST_F(AgeTableTest, SetAgeForMultipleCardsConsiderAdjacentCards) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   static constexpr size_t kNumberOfCards = 4;
   auto* page = AllocateNormalPage();
   Address object_begin = reinterpret_cast<Address>(
@@ -204,7 +200,6 @@ TEST_F(AgeTableTest, SetAgeForMultipleCardsConsiderAdjacentCards) {
 }
 
 TEST_F(AgeTableTest, MarkAllCardsAsYoung) {
-  subtle::DisallowGarbageCollectionScope disallow_gc(*Heap::From(GetHeap()));
   uint8_t* heap_start = reinterpret_cast<uint8_t*>(CagedHeapBase::GetBase());
   void* heap_end = heap_start + kCagedHeapReservationSize - 1;
   AssertAgeForAddressRange(heap_start, heap_end, Age::kOld);