Fix new space shrinking to compute correct capacity.

R=vegorov@chromium.org
BUG=v8:1702
TEST=cctest/test-heap/GrowAndShrinkNewSpace

Review URL: http://codereview.chromium.org/7983001

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9348 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/spaces.cc

@@ -925,10 +925,12 @@ void NewSpace::Flip() {
 
 
 void NewSpace::Grow() {
+  // Double the semispace size but only up to maximum capacity.
   ASSERT(Capacity() < MaximumCapacity());
-  if (to_space_.Grow()) {
+  int new_capacity = Min(MaximumCapacity(), 2 * static_cast<int>(Capacity()));
+  if (to_space_.GrowTo(new_capacity)) {
     // Only grow from space if we managed to grow to-space.
-    if (!from_space_.Grow()) {
+    if (!from_space_.GrowTo(new_capacity)) {
       // If we managed to grow to-space but couldn't grow from-space,
       // attempt to shrink to-space.
       if (!to_space_.ShrinkTo(from_space_.Capacity())) {
@@ -944,8 +946,7 @@ void NewSpace::Grow() {
 
 void NewSpace::Shrink() {
   int new_capacity = Max(InitialCapacity(), 2 * SizeAsInt());
-  int rounded_new_capacity =
-      RoundUp(new_capacity, static_cast<int>(OS::AllocateAlignment()));
+  int rounded_new_capacity = RoundUp(new_capacity, Page::kPageSize);
   if (rounded_new_capacity < Capacity() &&
       to_space_.ShrinkTo(rounded_new_capacity))  {
     // Only shrink from-space if we managed to shrink to-space.
@@ -1145,15 +1146,6 @@ bool SemiSpace::Uncommit() {
 }
 
 
-bool SemiSpace::Grow() {
-  // Double the semispace size but only up to maximum capacity.
-  ASSERT(static_cast<size_t>(Page::kPageSize) > OS::AllocateAlignment());
-  int new_capacity = Min(maximum_capacity_,
-      RoundUp(capacity_ * 2, static_cast<int>(Page::kPageSize)));
-  return GrowTo(new_capacity);
-}
-
-
 bool SemiSpace::GrowTo(int new_capacity) {
   ASSERT((new_capacity & Page::kPageAlignmentMask) == 0);
   ASSERT(new_capacity <= maximum_capacity_);
@@ -1210,7 +1202,7 @@ bool SemiSpace::ShrinkTo(int new_capacity) {
       NewSpacePage::FromAddress(space_end - pages_after * Page::kPageSize);
   new_last_page->set_next_page(anchor());
   anchor()->set_prev_page(new_last_page);
-  ASSERT(current_page_ == first_page());
+  ASSERT((current_page_ <= first_page()) && (current_page_ >= new_last_page));
 
   return true;
 }

src/spaces.h

@@ -1793,14 +1793,9 @@ class SemiSpace : public Space {
   // True if the space has been set up but not torn down.
   bool HasBeenSetup() { return start_ != NULL; }
 
-  // Grow the size of the semispace by committing extra virtual memory.
-  // Assumes that the caller has checked that the semispace has not reached
-  // its maximum capacity (and thus there is space available in the reserved
-  // address range to grow).
-  bool Grow();
-
   // Grow the semispace to the new capacity.  The new capacity
-  // requested must be larger than the current capacity.
+  // requested must be larger than the current capacity and less than
+  // the maximum capacity.
   bool GrowTo(int new_capacity);
 
   // Shrinks the semispace to the new capacity.  The new capacity

test/cctest/test-heap.cc

@@ -1233,9 +1233,8 @@ TEST(GrowAndShrinkNewSpace) {
   new_capacity = new_space->Capacity();
   ASSERT_EQ(2 * old_capacity, new_capacity);
 
-  // Fill up new space to the point that it exceeds old capacity.
-  while (new_space->SizeAsInt() <= old_capacity) {
-    Handle<FixedArray> filler = FACTORY->NewFixedArray(1000, NOT_TENURED);
+  // Fill up new space to the point that it is almost full.
+  while (new_space->SizeAsInt() + FixedArray::SizeFor(1000) < new_capacity) {
     ASSERT(HEAP->InNewSpace(*FACTORY->NewFixedArray(1000, NOT_TENURED)));
   }
 
@@ -1263,28 +1262,3 @@ TEST(GrowAndShrinkNewSpace) {
   new_capacity = new_space->Capacity();
   ASSERT_EQ(old_capacity, new_capacity);
 }
-
-
-class HeapIteratorTestHelper {
- public:
-  HeapIteratorTestHelper(Object* a, Object* b)
-      : a_(a), b_(b), a_found_(false), b_found_(false) {}
-  bool a_found() { return a_found_; }
-  bool b_found() { return b_found_; }
-  void IterateHeap() {
-    HeapIterator iterator;
-    for (HeapObject* obj = iterator.next();
-         obj != NULL;
-         obj = iterator.next()) {
-      if (obj == a_)
-        a_found_ = true;
-      else if (obj == b_)
-        b_found_ = true;
-    }
-  }
- private:
-  Object* a_;
-  Object* b_;
-  bool a_found_;
-  bool b_found_;
-};