v8/test/cctest/test-weakmaps.cc
mstarzinger@chromium.org 7d22d73ebf Fix issues when stressing compaction with WeakMaps.
1) While marking the backing hash table of a WeakMap we also need to
   record the slot because it might be on an evacuation candidate.
2) With incremental marking one backing hash table might be marked more
   than once because the WeakMap might have gone through a white to gray
   transition.
3) The corner case when the allocation of the backing hash table itself
   causes a GC, leads to a WeakMap with an undefined table field, so we
   still need to handle this case correctly.

R=vegorov@chromium.org
TEST=mjsunit/harmony/proxies-example-membrane --stress-compaction

Review URL: https://chromiumcodereview.appspot.com/9985010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11385 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-04-19 10:32:38 +00:00

227 lines
8.3 KiB
C++

// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "v8.h"
#include "global-handles.h"
#include "snapshot.h"
#include "cctest.h"
using namespace v8::internal;
static Handle<JSWeakMap> AllocateJSWeakMap() {
Handle<Map> map = FACTORY->NewMap(JS_WEAK_MAP_TYPE, JSWeakMap::kSize);
Handle<JSObject> weakmap_obj = FACTORY->NewJSObjectFromMap(map);
Handle<JSWeakMap> weakmap(JSWeakMap::cast(*weakmap_obj));
// Do not use handles for the hash table, it would make entries strong.
Object* table_obj = ObjectHashTable::Allocate(1)->ToObjectChecked();
ObjectHashTable* table = ObjectHashTable::cast(table_obj);
weakmap->set_table(table);
weakmap->set_next(Smi::FromInt(0));
return weakmap;
}
static void PutIntoWeakMap(Handle<JSWeakMap> weakmap,
Handle<JSObject> key,
Handle<Object> value) {
Handle<ObjectHashTable> table = PutIntoObjectHashTable(
Handle<ObjectHashTable>(ObjectHashTable::cast(weakmap->table())),
Handle<JSObject>(JSObject::cast(*key)),
value);
weakmap->set_table(*table);
}
static int NumberOfWeakCalls = 0;
static void WeakPointerCallback(v8::Persistent<v8::Value> handle, void* id) {
ASSERT(id == reinterpret_cast<void*>(1234));
NumberOfWeakCalls++;
handle.Dispose();
}
TEST(Weakness) {
FLAG_incremental_marking = false;
LocalContext context;
v8::HandleScope scope;
Handle<JSWeakMap> weakmap = AllocateJSWeakMap();
GlobalHandles* global_handles = Isolate::Current()->global_handles();
// Keep global reference to the key.
Handle<Object> key;
{
v8::HandleScope scope;
Handle<Map> map = FACTORY->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
Handle<JSObject> object = FACTORY->NewJSObjectFromMap(map);
key = global_handles->Create(*object);
}
CHECK(!global_handles->IsWeak(key.location()));
// Put entry into weak map.
{
v8::HandleScope scope;
PutIntoWeakMap(weakmap,
Handle<JSObject>(JSObject::cast(*key)),
Handle<Smi>(Smi::FromInt(23)));
}
CHECK_EQ(1, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
// Force a full GC.
HEAP->CollectAllGarbage(false);
CHECK_EQ(0, NumberOfWeakCalls);
CHECK_EQ(1, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
CHECK_EQ(
0, ObjectHashTable::cast(weakmap->table())->NumberOfDeletedElements());
// Make the global reference to the key weak.
{
v8::HandleScope scope;
global_handles->MakeWeak(key.location(),
reinterpret_cast<void*>(1234),
&WeakPointerCallback);
}
CHECK(global_handles->IsWeak(key.location()));
// Force a full GC.
// Perform two consecutive GCs because the first one will only clear
// weak references whereas the second one will also clear weak maps.
HEAP->CollectAllGarbage(false);
CHECK_EQ(1, NumberOfWeakCalls);
CHECK_EQ(1, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
CHECK_EQ(
0, ObjectHashTable::cast(weakmap->table())->NumberOfDeletedElements());
HEAP->CollectAllGarbage(false);
CHECK_EQ(1, NumberOfWeakCalls);
CHECK_EQ(0, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
CHECK_EQ(
1, ObjectHashTable::cast(weakmap->table())->NumberOfDeletedElements());
}
TEST(Shrinking) {
LocalContext context;
v8::HandleScope scope;
Handle<JSWeakMap> weakmap = AllocateJSWeakMap();
// Check initial capacity.
CHECK_EQ(32, ObjectHashTable::cast(weakmap->table())->Capacity());
// Fill up weak map to trigger capacity change.
{
v8::HandleScope scope;
Handle<Map> map = FACTORY->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
for (int i = 0; i < 32; i++) {
Handle<JSObject> object = FACTORY->NewJSObjectFromMap(map);
PutIntoWeakMap(weakmap, object, Handle<Smi>(Smi::FromInt(i)));
}
}
// Check increased capacity.
CHECK_EQ(128, ObjectHashTable::cast(weakmap->table())->Capacity());
// Force a full GC.
CHECK_EQ(32, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
CHECK_EQ(
0, ObjectHashTable::cast(weakmap->table())->NumberOfDeletedElements());
HEAP->CollectAllGarbage(false);
CHECK_EQ(0, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
CHECK_EQ(
32, ObjectHashTable::cast(weakmap->table())->NumberOfDeletedElements());
// Check shrunk capacity.
CHECK_EQ(32, ObjectHashTable::cast(weakmap->table())->Capacity());
}
// Test that weak map values on an evacuation candidate which are not reachable
// by other paths are correctly recorded in the slots buffer.
TEST(Regress2060a) {
FLAG_always_compact = true;
LocalContext context;
v8::HandleScope scope;
Handle<JSFunction> function =
FACTORY->NewFunction(FACTORY->function_symbol(), FACTORY->null_value());
Handle<JSObject> key = FACTORY->NewJSObject(function);
Handle<JSWeakMap> weakmap = AllocateJSWeakMap();
// Start second old-space page so that values land on evacuation candidate.
Page* first_page = HEAP->old_pointer_space()->anchor()->next_page();
FACTORY->NewFixedArray(900 * KB / kPointerSize, TENURED);
// Fill up weak map with values on an evacuation candidate.
{
v8::HandleScope scope;
for (int i = 0; i < 32; i++) {
Handle<JSObject> object = FACTORY->NewJSObject(function, TENURED);
CHECK(!HEAP->InNewSpace(object->address()));
CHECK(!first_page->Contains(object->address()));
PutIntoWeakMap(weakmap, key, object);
}
}
// Force compacting garbage collection.
CHECK(FLAG_always_compact);
HEAP->CollectAllGarbage(Heap::kNoGCFlags);
}
// Test that weak map keys on an evacuation candidate which are reachable by
// other strong paths are correctly recorded in the slots buffer.
TEST(Regress2060b) {
FLAG_always_compact = true;
#ifdef DEBUG
FLAG_verify_heap = true;
#endif
LocalContext context;
v8::HandleScope scope;
Handle<JSFunction> function =
FACTORY->NewFunction(FACTORY->function_symbol(), FACTORY->null_value());
// Start second old-space page so that keys land on evacuation candidate.
Page* first_page = HEAP->old_pointer_space()->anchor()->next_page();
FACTORY->NewFixedArray(900 * KB / kPointerSize, TENURED);
// Fill up weak map with keys on an evacuation candidate.
Handle<JSObject> keys[32];
for (int i = 0; i < 32; i++) {
keys[i] = FACTORY->NewJSObject(function, TENURED);
CHECK(!HEAP->InNewSpace(keys[i]->address()));
CHECK(!first_page->Contains(keys[i]->address()));
}
Handle<JSWeakMap> weakmap = AllocateJSWeakMap();
for (int i = 0; i < 32; i++) {
PutIntoWeakMap(weakmap, keys[i], Handle<Smi>(Smi::FromInt(i)));
}
// Force compacting garbage collection. The subsequent collections are used
// to verify that key references were actually updated.
CHECK(FLAG_always_compact);
HEAP->CollectAllGarbage(Heap::kNoGCFlags);
HEAP->CollectAllGarbage(Heap::kNoGCFlags);
HEAP->CollectAllGarbage(Heap::kNoGCFlags);
}