Revert of [heap] Remove border page

src/heap/heap-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_INL_H_
 #define V8_HEAP_HEAP_INL_H_
 
 #include <cmath>
 
 #include "src/base/platform/platform.h"
@@ skipping 464 matching lines @@
 bool Heap::InNewSpaceSlow(Address address) {
   return new_space_->ContainsSlow(address);
 }
 
 bool Heap::InOldSpaceSlow(Address address) {
   return old_space_->ContainsSlow(address);
 }
 
 template <PromotionMode promotion_mode>
 bool Heap::ShouldBePromoted(Address old_address, int object_size) {
+  Page* page = Page::FromAddress(old_address);
+  Address age_mark = new_space_->age_mark();
+
   if (promotion_mode == PROMOTE_MARKED) {
     MarkBit mark_bit = ObjectMarking::MarkBitFrom(old_address);
     if (!Marking::IsWhite(mark_bit)) {
       return true;
     }
   }
 
-  return Page::FromAddress(old_address)->InIntermediateGeneration();
+  return page->IsFlagSet(MemoryChunk::NEW_SPACE_BELOW_AGE_MARK) &&
+         (!page->ContainsLimit(age_mark) || old_address < age_mark);
 }
 
 PromotionMode Heap::CurrentPromotionMode() {
   if (incremental_marking()->IsMarking()) {
     return PROMOTE_MARKED;
   } else {
     return DEFAULT_PROMOTION;
   }
 }
 
@@ skipping 80 matching lines @@
   // below (memento_address == top) ensures that this is safe. Mark the word as
   // initialized to silence MemorySanitizer warnings.
   MSAN_MEMORY_IS_INITIALIZED(&candidate_map, sizeof(candidate_map));
   if (candidate_map != allocation_memento_map()) {
     return nullptr;
   }
 
   // Bail out if the memento is below the age mark, which can happen when
   // mementos survived because a page got moved within new space.
   Page* object_page = Page::FromAddress(object_address);
-  if (object_page->InIntermediateGeneration()) {
-    return nullptr;
+  if (object_page->IsFlagSet(Page::NEW_SPACE_BELOW_AGE_MARK)) {
+    Address age_mark =
+        reinterpret_cast<SemiSpace*>(object_page->owner())->age_mark();
+    if (!object_page->Contains(age_mark)) {
+      return nullptr;
+    }
+    // Do an exact check in the case where the age mark is on the same page.
+    if (object_address < age_mark) {
+      return nullptr;
+    }
   }
 
   AllocationMemento* memento_candidate = AllocationMemento::cast(candidate);
 
   // Depending on what the memento is used for, we might need to perform
   // additional checks.
   Address top;
   switch (mode) {
     case Heap::kForGC:
       return memento_candidate;
@@ skipping 225 matching lines @@
 
 void VerifySmisVisitor::VisitPointers(Object** start, Object** end) {
   for (Object** current = start; current < end; current++) {
     CHECK((*current)->IsSmi());
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_INL_H_