1 files changed, 16 insertions, 5 deletions

diff --git a/Source/JavaScriptCore/heap/MarkedAllocator.cpp b/Source/JavaScriptCore/heap/MarkedAllocator.cpp
index 465e3a72a..20b556969 100644
--- a/Source/JavaScriptCore/heap/MarkedAllocator.cpp
+++ b/Source/JavaScriptCore/heap/MarkedAllocator.cpp
@@ -3,6 +3,7 @@
 
 #include "GCActivityCallback.h"
 #include "Heap.h"
+#include "IncrementalSweeper.h"
 #include "JSGlobalData.h"
 #include <wtf/CurrentTime.h>
 
@@ -11,7 +12,7 @@ namespace JSC {
 bool MarkedAllocator::isPagedOut(double deadline)
 {
     unsigned itersSinceLastTimeCheck = 0;
-    HeapBlock* block = m_blockList.head();
+    MarkedBlock* block = m_blockList.head();
     while (block) {
         block = block->next();
         ++itersSinceLastTimeCheck;
@@ -29,7 +30,18 @@ bool MarkedAllocator::isPagedOut(double deadline)
 inline void* MarkedAllocator::tryAllocateHelper()
 {
     if (!m_freeList.head) {
-        for (MarkedBlock*& block = m_blocksToSweep; block; block = static_cast<MarkedBlock*>(block->next())) {
+        if (m_onlyContainsStructures && !m_heap->isSafeToSweepStructures()) {
+            if (m_currentBlock) {
+                m_currentBlock->didConsumeFreeList();
+                m_currentBlock = 0;
+            }
+            // We sweep another random block here so that we can make progress
+            // toward being able to sweep Structures.
+            m_heap->sweeper()->sweepNextBlock();
+            return 0;
+        }
+
+        for (MarkedBlock*& block = m_blocksToSweep; block; block = block->next()) {
             m_freeList = block->sweep(MarkedBlock::SweepToFreeList);
             if (m_freeList.head) {
                 m_currentBlock = block;
@@ -104,7 +116,6 @@ MarkedBlock* MarkedAllocator::allocateBlock()
 void MarkedAllocator::addBlock(MarkedBlock* block)
 {
     ASSERT(!m_currentBlock);
-    ASSERT(!m_blocksToSweep);
     ASSERT(!m_freeList.head);
     
     m_blockList.append(block);
@@ -115,11 +126,11 @@ void MarkedAllocator::addBlock(MarkedBlock* block)
 void MarkedAllocator::removeBlock(MarkedBlock* block)
 {
     if (m_currentBlock == block) {
-        m_currentBlock = static_cast<MarkedBlock*>(m_currentBlock->next());
+        m_currentBlock = m_currentBlock->next();
         m_freeList = MarkedBlock::FreeList();
     }
     if (m_blocksToSweep == block)
-        m_blocksToSweep = static_cast<MarkedBlock*>(m_blocksToSweep->next());
+        m_blocksToSweep = m_blocksToSweep->next();
     m_blockList.remove(block);
 }