[heap] Reland move slot filtering logic into sweeper.

test/unittests/heap/slot-set-unittest.cc

 // Copyright 2016 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.
 
 #include <limits>
 
 #include "src/globals.h"
 #include "src/heap/slot-set.h"
 #include "src/heap/spaces.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 83 matching lines @@
       EXPECT_FALSE(set.Lookup(i));
     }
   }
 }
 
 void CheckRemoveRangeOn(uint32_t start, uint32_t end) {
   SlotSet set;
   set.SetPageStart(0);
   uint32_t first = start == 0 ? 0 : start - kPointerSize;
   uint32_t last = end == Page::kPageSize ? end - kPointerSize : end;
-  for (uint32_t i = first; i <= last; i += kPointerSize) {
-    set.Insert(i);
-  }
-  set.RemoveRange(start, end, SlotSet::FREE_EMPTY_BUCKETS);
-  if (first != start) {
-    EXPECT_TRUE(set.Lookup(first));
-  }
-  if (last == end) {
-    EXPECT_TRUE(set.Lookup(last));
-  }
-  for (uint32_t i = start; i < end; i += kPointerSize) {
-    EXPECT_FALSE(set.Lookup(i));
+  for (const auto mode :
+       {SlotSet::FREE_EMPTY_BUCKETS, SlotSet::KEEP_EMPTY_BUCKETS}) {
+    for (uint32_t i = first; i <= last; i += kPointerSize) {
+      set.Insert(i);
+    }
+    set.RemoveRange(start, end, mode);
+    if (first != start) {
+      EXPECT_TRUE(set.Lookup(first));
+    }
+    if (last == end) {
+      EXPECT_TRUE(set.Lookup(last));
+    }
+    for (uint32_t i = start; i < end; i += kPointerSize) {
+      EXPECT_FALSE(set.Lookup(i));
+    }
   }
 }
 
 TEST(SlotSet, RemoveRange) {
   CheckRemoveRangeOn(0, Page::kPageSize);
   CheckRemoveRangeOn(1 * kPointerSize, 1023 * kPointerSize);
   for (uint32_t start = 0; start <= 32; start++) {
     CheckRemoveRangeOn(start * kPointerSize, (start + 1) * kPointerSize);
     CheckRemoveRangeOn(start * kPointerSize, (start + 2) * kPointerSize);
     const uint32_t kEnds[] = {32, 64, 100, 128, 1024, 1500, 2048};
     for (int i = 0; i < sizeof(kEnds) / sizeof(uint32_t); i++) {
       for (int k = -3; k <= 3; k++) {
         uint32_t end = (kEnds[i] + k);
         if (start < end) {
           CheckRemoveRangeOn(start * kPointerSize, end * kPointerSize);
         }
       }
     }
   }
   SlotSet set;
   set.SetPageStart(0);
-  set.Insert(Page::kPageSize / 2);
-  set.RemoveRange(0, Page::kPageSize, SlotSet::FREE_EMPTY_BUCKETS);
-  for (uint32_t i = 0; i < Page::kPageSize; i += kPointerSize) {
-    EXPECT_FALSE(set.Lookup(i));
+  for (const auto mode :
+       {SlotSet::FREE_EMPTY_BUCKETS, SlotSet::KEEP_EMPTY_BUCKETS}) {
+    set.Insert(Page::kPageSize / 2);
+    set.RemoveRange(0, Page::kPageSize, mode);
+    for (uint32_t i = 0; i < Page::kPageSize; i += kPointerSize) {
+      EXPECT_FALSE(set.Lookup(i));
+    }
   }
 }
 
 TEST(TypedSlotSet, Iterate) {
   TypedSlotSet set(0);
   const int kDelta = 10000001;
   const int kHostDelta = 50001;
   int added = 0;
   uint32_t j = 0;
   for (uint32_t i = 0; i < TypedSlotSet::kMaxOffset;
@@ skipping 24 matching lines @@
         EXPECT_EQ(0, i % 2);
         ++iterated;
         return KEEP_SLOT;
       },
       TypedSlotSet::KEEP_EMPTY_CHUNKS);
   EXPECT_EQ(added / 2, iterated);
 }
 
 }  // namespace internal
 }  // namespace v8