deps: cherry-pick 09db540,686558d from V8 upstream

abernix · MylesBorins · commit 71f9cdf24197 · 2017-10-25T04:22:55.000-04:00
Original commit messages: v8/v8@09db540 Reland of Rehash and clear deleted entries in weak collections during GC BUG=v8:4909 R=hpayer@chromium.org,ulan@chromium.org LOG=n Review URL: https://codereview.chromium.org/1890123002 Cr-Commit-Position: refs/heads/master@{#35538} v8/v8@686558d Fix comment about when we rehash ObjectHashTables before growing them R=ulan@chromium.org BUG= Review-Url: https://codereview.chromium.org/1918403003 Cr-Commit-Position: refs/heads/master@{#35853} Refs: https://crbug.com/v8/4909 Refs: #6180 Refs: #7689 Refs: #6398 Fixes: #14228 PR-URL: #14829 Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
diff --git a/deps/v8/include/v8-version.h b/deps/v8/include/v8-version.h
@@ -11,7 +11,7 @@
 #define V8_MAJOR_VERSION 4
 #define V8_MINOR_VERSION 5
 #define V8_BUILD_NUMBER 103
-#define V8_PATCH_LEVEL 48
+#define V8_PATCH_LEVEL 49
 
 // Use 1 for candidates and 0 otherwise.
 // (Boolean macro values are not supported by all preprocessors.)
diff --git a/deps/v8/src/objects.cc b/deps/v8/src/objects.cc
@@ -13744,6 +13744,16 @@ void HashTable<Derived, Shape, Key>::Rehash(Key key) {
       }
     }
   }
+  // Wipe deleted entries.
+  Heap* heap = GetHeap();
+  Object* the_hole = heap->the_hole_value();
+  Object* undefined = heap->undefined_value();
+  for (uint32_t current = 0; current < capacity; current++) {
+    if (get(EntryToIndex(current)) == the_hole) {
+      set(EntryToIndex(current), undefined);
+    }
+  }
+  SetNumberOfDeletedElements(0);
 }
 
 
@@ -15198,6 +15208,11 @@ Handle<ObjectHashTable> ObjectHashTable::Put(Handle<ObjectHashTable> table,
     return table;
   }
 
+  // Rehash if more than 33% of the entries are deleted entries.
+  // TODO(jochen): Consider to shrink the fixed array in place.
+  if ((table->NumberOfDeletedElements() << 1) > table->NumberOfElements()) {
+    table->Rehash(isolate->factory()->undefined_value());
+  }
   // If we're out of luck, we didn't get a GC recently, and so rehashing
   // isn't enough to avoid a crash.
   if (!table->HasSufficientCapacityToAdd(1)) {

Original file line number	Diff line number	Diff line change
`@@ -13744,6 +13744,16 @@ void HashTable<Derived, Shape, Key>::Rehash(Key key) {`
`13744`	`13744`	`}`
`13745`	`13745`	`}`
`13746`	`13746`	`}`
	`13747`	`+ // Wipe deleted entries.`
	`13748`	`+ Heap* heap = GetHeap();`
	`13749`	`+ Object* the_hole = heap->the_hole_value();`
	`13750`	`+ Object* undefined = heap->undefined_value();`
	`13751`	`+ for (uint32_t current = 0; current < capacity; current++) {`
	`13752`	`+ if (get(EntryToIndex(current)) == the_hole) {`
	`13753`	`+ set(EntryToIndex(current), undefined);`
	`13754`	`+ }`
	`13755`	`+ }`
	`13756`	`+ SetNumberOfDeletedElements(0);`
`13747`	`13757`	`}`
`13748`	`13758`
`13749`	`13759`
`@@ -15198,6 +15208,11 @@ Handle<ObjectHashTable> ObjectHashTable::Put(Handle<ObjectHashTable> table,`
`15198`	`15208`	`return table;`
`15199`	`15209`	`}`
`15200`	`15210`
	`15211`	`+ // Rehash if more than 33% of the entries are deleted entries.`
	`15212`	`+ // TODO(jochen): Consider to shrink the fixed array in place.`
	`15213`	`+ if ((table->NumberOfDeletedElements() << 1) > table->NumberOfElements()) {`
	`15214`	`+ table->Rehash(isolate->factory()->undefined_value());`
	`15215`	`+ }`
`15201`	`15216`	`// If we're out of luck, we didn't get a GC recently, and so rehashing`
`15202`	`15217`	`// isn't enough to avoid a crash.`
`15203`	`15218`	`if (!table->HasSufficientCapacityToAdd(1)) {`