internal static unsafe void SetStaticDataPages(UIntPtr startAddr,
UIntPtr size)
{
#if SINGULARITY
// It's perfectly fine to be given memory outside the page table region, so
// long as we intend to treat that memory as NonGC anyway.
if (startAddr < PageTable.baseAddr)
{
if (startAddr + size < PageTable.baseAddr)
{
// nothing to do. All pages are below the base covered by the page table
return;
}
// The range overlaps with the region covered by the page table
size -= (PageTable.baseAddr - startAddr);
startAddr = PageTable.baseAddr;
}
UIntPtr endAddr = startAddr + size;
if (endAddr > PageTable.limitAddr)
{
if (startAddr > PageTable.limitAddr)
{
// nothing to do. All pages are above the limit covered by the page table
return;
}
// The range overlaps with the region covered by the page table
size -= (PageTable.limitAddr - endAddr);
}
#endif
UIntPtr startIndex = PageTable.Page(startAddr);
UIntPtr pageCount = PageTable.PageCount(size);
PageTable.SetType(startIndex, pageCount, PageType.NonGC);
}
internal static bool TryReservePages(Thread currentThread,
UIntPtr startPage,
UIntPtr pageCount,
PageType newType,
ref bool fCleanPages)
{
Trace.Log(Trace.Area.Page,
"TryReservePages start={0:x} count={1:x}",
__arglist(startPage, pageCount));
VTable.Deny(PageTable.IsUnusedPageType(newType));
VTable.Assert(pageCount > UIntPtr.Zero);
VTable.Deny(startPage != UIntPtr.Zero &&
PageTable.IsUnusedPage(startPage - 1) &&
PageTable.IsMyPage(startPage - 1));
UIntPtr endPage = startPage + pageCount;
UIntPtr index = startPage;
while (index < endPage &&
PageTable.IsUnusedPage(index) &&
PageTable.IsMyPage(index))
{
index++;
}
if (PageTable.IsUnallocatedPage(PageTable.Type(index)))
{
// We should try to extend the region of allocated pages
UIntPtr pagesNeeded = pageCount - (index - startPage);
UIntPtr bytesNeeded = PageTable.RegionSize(pagesNeeded);
UIntPtr allocSize = Util.Pad(bytesNeeded, heap_commit_size);
UIntPtr startAddr = PageTable.PageAddr(index);
bool gotMemory = false;
bool iflag = EnterMutex(currentThread);
try {
gotMemory =
MemoryManager.AllocateMemory(startAddr, allocSize);
if (gotMemory)
{
UIntPtr allocPages = PageTable.PageCount(allocSize);
MarkUnusedPages(/* avoid recursive locking */ null,
index, allocPages, true);
}
} finally {
LeaveMutex(currentThread, iflag);
}
if (gotMemory)
{
bool success =
TryReserveUnusedPages(currentThread, startPage,
pageCount, newType,
ref fCleanPages);
Trace.Log(Trace.Area.Page,
"TryReservePages success={0}",
__arglist(success));
return(success);
}
}
return(false);
}
private UIntPtr FreshAlloc(UIntPtr bytes, uint alignment,
Thread currentThread)
{
#if SINGULARITY_KERNEL
Kernel.Waypoint(702);
#endif
this.Truncate();
UIntPtr paddedBytes =
PageTable.PagePad(bytes + alignment - UIntPtr.Size);
BaseCollector.IncrementNewBytesSinceGC(paddedBytes);
UIntPtr pages = PageTable.PageCount(paddedBytes);
bool fCleanPages = CLEAR_POOL_PAGES();
// We may eventually want to ask for specific pages
// between asking if any pages are reusable and asking the
// OS for any possible page.
UIntPtr startPage =
PageManager.EnsurePages(currentThread, pages, this.pageType,
ref fCleanPages);
UIntPtr startAddr = PageTable.PageAddr(startPage);
UIntPtr limitAddr = PageTable.PageAddr(startPage + pages);
startAddr = Allocator.AlignedAllocationPtr(startAddr, limitAddr,
alignment);
this.allocNew = startAddr;
this.allocPtr = startAddr + bytes;
if (fCleanPages)
{
this.zeroedLimit = limitAddr;
}
else
{
Util.MemClear(startAddr, bytes);
this.zeroedLimit = this.allocPtr;
}
this.reserveLimit = limitAddr;
UIntPtr resultAddr = startAddr + PreHeader.Size;
InteriorPtrTable.SetFirst(resultAddr);
#if !SINGULARITY || SEMISPACE_COLLECTOR || ADAPTIVE_COPYING_COLLECTOR || SLIDING_COLLECTOR
if (GC.remsetType == RemSetType.Cards)
{
UIntPtr nextPageAddr = startAddr + PageTable.PageSize;
VTable.Assert(resultAddr < nextPageAddr);
if (this.allocPtr > nextPageAddr)
{
#if DONT_RECORD_OBJALLOC_IN_OFFSETTABLE
#else
OffsetTable.SetLast(resultAddr);
#endif
}
}
#endif
#if SINGULARITY_KERNEL
Kernel.Waypoint(703);
#endif
return(resultAddr);
}
private static void Clear(UIntPtr startAddr,
UIntPtr regionSize)
{
VTable.Assert(PageTable.PageAligned(startAddr));
VTable.Assert(PageTable.PageAligned(regionSize));
MemoryManager.IgnoreMemoryContents(startAddr, regionSize);
MarkUnusedPages(Thread.CurrentThread,
PageTable.Page(startAddr),
PageTable.PageCount(regionSize),
false);
}
private UIntPtr growFreeList(UIntPtr blockSize, Thread t)
{
UIntPtr pageCount = PageTable.PageCount(blockSize);
bool fCleanPages = true;
UIntPtr startPage = PageManager.EnsurePages(t, pageCount,
PageType.Owner0,
ref fCleanPages);
UIntPtr newBlockSize = PageTable.RegionSize(pageCount);
UIntPtr newBlockAddr = PageTable.PageAddr(startPage);
return(FreeBlock(newBlockAddr, newBlockSize));
}
internal static void Initialize(UIntPtr systemMemorySize)
{
allocPtr = MemoryManager.AllocateMemory(systemMemorySize);
limitPtr = allocPtr + systemMemorySize;
if (GC.gcType != GCType.NullCollector)
{
PageManager.SetStaticDataPages(allocPtr, systemMemorySize);
#if !SINGULARITY
PageTable.SetProcess(PageTable.Page(allocPtr),
PageTable.PageCount(systemMemorySize));
#endif
}
}
internal static void Truncate()
{
UIntPtr allocLimit = PageTable.PagePad(allocPtr);
UIntPtr unusedSize = limitPtr - allocLimit;
if (GC.gcType != GCType.NullCollector)
{
PageManager.ReleaseUnusedPages(PageTable.Page(allocLimit),
PageTable.PageCount(unusedSize),
true);
}
limitPtr = allocLimit;
}
internal override void CollectGeneration(int generation,
UIntPtr generationPageCount)
{
UIntPtr availableMemory = (UIntPtr)
(MemoryManager.MemorySize - MemoryManager.OperatingSystemSize);
UIntPtr softPageCountLimit = PageTable.PageCount(availableMemory);
if (generation == (int)MAX_GENERATION &&
(generationPageCount << 1) > softPageCountLimit)
{
// Use sliding collector when fromSpace > 1/2 available memory
SlidingCollector.instance.CollectGeneration(generation, generationPageCount);
}
else
{
SemispaceCollector.instance.CollectGeneration(generation, generationPageCount);
}
}
// Low-level routines based on the operating system interface
private static unsafe UIntPtr AllocateMemoryHelper(UIntPtr startAddr,
UIntPtr size)
{
void *result = VirtualAlloc((void *)startAddr,
size, MEM_RESERVE, PAGE_READWRITE);
VTable.Assert
(PageTable.Page((UIntPtr)result + size - 1)
< PageTable.pageTableCount,
"OutOfMemory: MemoryManager: memory doesn't fit in page table");
if (result != null)
{
Trace.Log(Trace.Area.Page,
"VirtualAlloc {0} at {1}",
__arglist(size, result));
VTable.Assert((startAddr == UIntPtr.Zero) ||
(result == (void *)startAddr));
void *area = VirtualAlloc(result, size,
MEM_COMMIT, PAGE_READWRITE);
if (PageTable.halPageDescriptor != null)
{
PageTable.CreateNewPageTablesIfNecessary(PageTable.Page((UIntPtr)result), PageTable.PageCount(size));
PageTable.SetProcess(PageTable.Page((UIntPtr)area),
PageTable.PageCount(size));
}
VTable.Assert(result == area);
#if HIMEM
// This assertion intends only to catch bugs in Bartok. But if
// the system (windows) frees memory before, the memory
// may be in low memory, and if we happen to get that
// memory, this assertion itself may not hold
VTable.Assert((UIntPtr)result >= PageTable.HIMEMStart,
("High memory is expected to be allocated in HIMEM mode"));
#endif
}
return(new UIntPtr(result));
}
internal unsafe static void ReportNonGCDetails()
{
VTable.DebugPrint("\nNon-GC data details:\n");
uint totalPageCount = TotalNumPages(PageType.NonGC);
VTable.DebugPrint("\tTotal number of pages: {0}",
__arglist(totalPageCount));
VTable.DebugPrint("\n\tMemory accounting storage: {0}B",
__arglist((uint)totalSize));
staticPtrs.Initialize();
uint staticSize = StaticData.ScanStaticPointerData(staticPtrs);
VTable.DebugPrint("\n\tCompile-time allocated data: {0}B",
__arglist(staticSize));
VTable.DebugPrint("\n\tNumber of pointers: {0}",
__arglist(staticPtrs.PtrCount));
uint bootstrapPageCount = totalPageCount -
(uint)PageTable.PageCount((UIntPtr)staticSize);
VTable.DebugPrint("\n\tNumber of bootstrap pages: {0}\n",
__arglist(bootstrapPageCount));
}
// Interface with the compiler!
internal static unsafe UIntPtr AllocateBig(UIntPtr numBytes,
uint alignment,
Thread currentThread)
{
// Pretenure Trigger
pretenuredSinceLastFullGC += numBytes;
if (pretenuredSinceLastFullGC > PretenureHardGCTrigger)
{
GC.InvokeMajorCollection(currentThread);
}
// Potentially Join a collection
GC.CheckForNeededGCWork(currentThread);
int maxAlignmentOverhead = unchecked ((int)alignment) - UIntPtr.Size;
UIntPtr pageCount =
PageTable.PageCount(numBytes + maxAlignmentOverhead);
bool fCleanPages = true;
UIntPtr page = PageManager.EnsurePages(currentThread, pageCount,
largeObjectGeneration,
ref fCleanPages);
int unusedBytes =
unchecked ((int)(PageTable.RegionSize(pageCount) - numBytes));
int unusedCacheLines =
unchecked ((int)(unusedBytes - maxAlignmentOverhead)) >> 5;
int pageOffset = 0;
if (unusedCacheLines != 0)
{
pageOffset = (bigOffset % unusedCacheLines) << 5;
bigOffset++;
}
UIntPtr pageStart = PageTable.PageAddr(page);
for (int i = 0; i < pageOffset; i += UIntPtr.Size)
{
Allocator.WriteAlignment(pageStart + i);
}
UIntPtr unalignedStartAddr = pageStart + pageOffset;
UIntPtr startAddr =
Allocator.AlignedAllocationPtr(unalignedStartAddr,
pageStart + unusedBytes,
alignment);
pageOffset +=
unchecked ((int)(uint)(startAddr - unalignedStartAddr));
if (pageOffset < unusedBytes)
{
BumpAllocator.WriteUnusedMarker(pageStart + pageOffset + numBytes);
}
UIntPtr resultAddr = startAddr + PreHeader.Size;
InteriorPtrTable.SetFirst(resultAddr);
VTable.Assert(PageTable.Page(resultAddr) <
PageTable.Page(startAddr + numBytes - 1),
"Big object should cross pages");
if (GC.remsetType == RemSetType.Cards)
{
#if DONT_RECORD_OBJALLOC_IN_OFFSETTABLE
#else
OffsetTable.SetLast(resultAddr);
#endif
}
return(resultAddr);
}
private unsafe void FindDestinationArea(ref UIntPtr destPage,
ref UIntPtr destCursor,
ref UIntPtr destLimit,
UIntPtr objectSize,
PageType destGeneration)
{
VTable.Assert(IsValidGeneration((int)destGeneration));
UIntPtr cursorPage = PageTable.Page(destCursor);
UIntPtr limitPage = PageTable.Page(destLimit);
UIntPtr pageAddr = PageTable.PagePad(destCursor);
UIntPtr testPage = limitPage;
UIntPtr endTestPage = PageTable.PageCount(destCursor + objectSize);
if (destCursor > UIntPtr.Zero &&
IsMyZombiePage(PageTable.Page(destCursor - 1)))
{
VTable.Assert(destPage == limitPage);
while (IsMyZombiePage(testPage) ||
(testPage < endTestPage &&
(PageTable.IsUnusedPage(testPage))))
{
testPage++;
}
if (testPage >= endTestPage)
{
// We can expand the current region
endTestPage = testPage;
VTable.Assert(PageTable.PageAligned(destLimit));
InteriorPtrTable.ClearFirst(limitPage, testPage);
if (GC.remsetType == RemSetType.Cards)
{
OffsetTable.ClearLast(PageTable.PageAddr(limitPage),
PageTable.PageAddr(testPage) - 1);
}
while (limitPage != endTestPage)
{
VTable.Assert(PageTable.IsUnusedPage(destPage));
do
{
destPage++;
} while (destPage < endTestPage &&
PageTable.IsUnusedPage(destPage));
bool fCleanPages = true;
bool status =
PageManager.TryReserveUnusedPages(null, limitPage,
destPage - limitPage,
nurseryGeneration,
ref fCleanPages);
VTable.Assert(status);
MakeZombiePages(limitPage, destPage - limitPage,
destGeneration);
while (destPage < endTestPage &&
IsMyZombiePage(destPage))
{
destPage++;
}
limitPage = destPage;
}
destLimit = PageTable.PageAddr(limitPage);
return;
}
}
if (destCursor != pageAddr)
{
cursorPage++;
}
if (cursorPage != limitPage)
{
this.RegisterSkippedPages(cursorPage, limitPage);
}
// Find new region big enough to contain object
UIntPtr neededPages = PageTable.PageCount(objectSize);
UIntPtr prefixPage;
while (true)
{
do
{
destPage++;
} while (!IsMyZombiePage(destPage));
cursorPage = destPage;
prefixPage = cursorPage;
do
{
destPage++;
} while (IsMyZombiePage(destPage));
limitPage = destPage;
if (neededPages <= limitPage - cursorPage)
{
break;
}
// Check for following unused pages
endTestPage = cursorPage + neededPages;
VTable.Assert(endTestPage <= PageTable.pageTableCount);
while (destPage < endTestPage &&
(PageTable.IsUnusedPage(destPage) ||
(IsMyZombiePage(destPage))))
{
destPage++;
}
if (destPage == endTestPage)
{
break;
}
// Check for preceding unused pages
if (destPage >= neededPages)
{
endTestPage = destPage - neededPages;
prefixPage = cursorPage - 1;
while (prefixPage >= UIntPtr.Zero &&
PageTable.IsUnusedPage(prefixPage))
{
prefixPage--;
}
prefixPage++;
if (prefixPage == endTestPage)
{
break;
}
}
// Register any skipped regions of pages
this.RegisterSkippedPages(cursorPage, limitPage);
while (limitPage < destPage)
{
VTable.Assert(PageTable.IsUnusedPage(limitPage));
do
{
limitPage++;
} while (limitPage < destPage &&
PageTable.IsUnusedPage(limitPage));
cursorPage = limitPage;
while (limitPage < destPage && IsMyZombiePage(limitPage))
{
limitPage++;
}
if (cursorPage != limitPage)
{
this.RegisterSkippedPages(cursorPage, limitPage);
}
}
}
// We found an area big enough. Commit the pre- and
// postfix areas of unused pages
if (prefixPage != cursorPage)
{
bool fCleanPages = true;
bool status =
PageManager.TryReserveUnusedPages(null, prefixPage,
cursorPage - prefixPage,
nurseryGeneration,
ref fCleanPages);
VTable.Assert(status);
MakeZombiePages(prefixPage, cursorPage - prefixPage,
destGeneration);
}
while (destPage != limitPage)
{
// Mark the region of unused pages as fromspace
UIntPtr unusedPage = limitPage;
VTable.Assert(PageTable.IsUnusedPage(unusedPage));
do
{
unusedPage++;
} while (unusedPage < destPage &&
PageTable.IsUnusedPage(unusedPage));
bool fCleanPages = true;
bool status =
PageManager.TryReserveUnusedPages(null, limitPage,
unusedPage - limitPage,
nurseryGeneration,
ref fCleanPages);
VTable.Assert(status);
MakeZombiePages(limitPage, unusedPage - limitPage,
destGeneration);
// Skip any sections of pages already marked as fromspace
limitPage = unusedPage;
while (limitPage < destPage && IsMyZombiePage(limitPage))
{
limitPage++;
}
}
destCursor = PageTable.PageAddr(prefixPage);
destLimit = PageTable.PageAddr(limitPage);
// Take ownership of the new pages
InteriorPtrTable.ClearFirst(prefixPage, limitPage);
InteriorPtrTable.SetFirst(destCursor + PreHeader.Size);
if (GC.remsetType == RemSetType.Cards)
{
OffsetTable.ClearLast(PageTable.PageAddr(prefixPage),
PageTable.PageAddr(limitPage) - 1);
}
}
internal static void ReleaseUnusedPages(UIntPtr startPage,
UIntPtr pageCount,
bool fCleanPages)
{
if (VTable.enableDebugPrint)
{
VTable.DebugPrint("ClearPages({0}, {1})\n",
__arglist(startPage, pageCount));
}
UIntPtr startAddr = PageTable.PageAddr(startPage);
UIntPtr endPage = startPage + pageCount;
UIntPtr endAddr = PageTable.PageAddr(endPage);
UIntPtr rangeSize = PageTable.RegionSize(pageCount);
MarkUnusedPages(Thread.CurrentThread,
PageTable.Page(startAddr),
PageTable.PageCount(rangeSize),
fCleanPages);
if (PageManager.AggressiveMemReset)
{
// We cannot simply reset the memory range, as MEM_RESET can
// only be used within a region returned from a single
// VirtualAlloc call.
UIntPtr regionAddr, regionSize;
bool fUsed = MemoryManager.QueryMemory(startAddr,
out regionAddr,
out regionSize);
if (VTable.enableDebugPrint)
{
VTable.DebugPrint(" 1 Query({0}, {1}, {2}) -> {3}\n",
__arglist(startAddr, regionAddr,
regionSize, fUsed));
}
VTable.Assert(fUsed, "Memory to be cleared isn't used");
// We don't care if regionAddr < startAddr. We can MEM_RESET
// part of the region.
UIntPtr endRegion = regionAddr + regionSize;
while (endRegion < endAddr)
{
if (VTable.enableDebugPrint)
{
VTable.DebugPrint("Clearing region [{0}, {1}]\n",
__arglist(regionAddr,
regionAddr + regionSize));
}
MemoryManager.IgnoreMemoryContents(startAddr,
endRegion - startAddr);
startAddr = endRegion;
fUsed = MemoryManager.QueryMemory(endRegion,
out regionAddr,
out regionSize);
if (VTable.enableDebugPrint)
{
VTable.DebugPrint(" 2 Query({0}, {1}, {2}) -> {3}\n",
__arglist(endRegion, regionAddr,
regionSize, fUsed));
}
VTable.Assert(fUsed, "Region to be freed isn't used");
endRegion = regionAddr + regionSize;
}
if (VTable.enableDebugPrint)
{
VTable.DebugPrint("Clearing final region [{0}, {1}]\n",
__arglist(startAddr, endAddr));
}
MemoryManager.IgnoreMemoryContents(startAddr,
endAddr - startAddr);
}
if (VTable.enableDebugPrint)
{
VTable.DebugPrint(" --> ClearPages({0},{1})\n",
__arglist(startPage, pageCount));
}
}
internal static UIntPtr EnsurePages(Thread currentThread,
UIntPtr pageCount,
PageType newType,
ref bool fCleanPages)
{
if (currentThread != null)
{
GC.CheckForNeededGCWork(currentThread);
}
VTable.Deny(PageTable.IsUnusedPageType(newType));
// Try to find already allocated but unused pages
UIntPtr foundPages =
FindUnusedPages(currentThread, pageCount, newType);
if (foundPages != UIntPtr.Zero)
{
if (fCleanPages)
{
CleanFoundPages(foundPages);
}
else
{
fCleanPages = FoundOnlyCleanPages(foundPages);
}
return(foundPages);
}
// We need to allocate new pages
bool iflag = EnterMutex(currentThread);
try {
UIntPtr bytesNeeded = PageTable.RegionSize(pageCount);
UIntPtr allocSize = Util.Pad(bytesNeeded, heap_commit_size);
UIntPtr startAddr = MemoryManager.AllocateMemory(allocSize);
if (startAddr == UIntPtr.Zero)
{
if (heap_commit_size > os_commit_size)
{
allocSize = Util.Pad(bytesNeeded, os_commit_size);
startAddr = MemoryManager.AllocateMemory(allocSize);
}
}
if (startAddr == UIntPtr.Zero)
{
// BUGBUG: if in CMS, should wait on one complete GC cycle and
// the retry. for STW, we may get here even if the collector
// hasn't triggered just prior.
PageTable.Dump("Out of memory");
throw outOfMemoryException;
}
UIntPtr startPage = PageTable.Page(startAddr);
PageTable.SetType(startPage, pageCount, newType);
PageTable.SetProcess(startPage, pageCount);
UIntPtr extraPages =
PageTable.PageCount(allocSize) - pageCount;
if (extraPages > 0)
{
// Mark the new memory pages as allocated-but-unused
MarkUnusedPages(/* avoid recursive locking */ null,
startPage + pageCount, extraPages,
true);
}
return(startPage);
} finally {
LeaveMutex(currentThread, iflag);
}
}
private UIntPtr ExtendAlloc(UIntPtr bytes, uint alignment,
Thread currentThread)
{
if (this.reserveLimit == UIntPtr.Zero)
{
return(UIntPtr.Zero);
}
#if SINGULARITY_KERNEL
Kernel.Waypoint(700);
#endif
UIntPtr neededBytes =
bytes + // Bytes required for object +
alignment - UIntPtr.Size - // worst case alignment overhead +
(this.reserveLimit - this.allocPtr); // bytes already available
UIntPtr paddedNeed = PageTable.PagePad(neededBytes);
UIntPtr pageCount = PageTable.PageCount(paddedNeed);
UIntPtr startPage = PageTable.Page(this.reserveLimit);
bool fCleanPages = CLEAR_POOL_PAGES();
bool gotPages =
PageManager.TryReserveUnusedPages(currentThread, startPage,
pageCount, this.pageType,
ref fCleanPages);
if (!gotPages)
{
// We can't indiscriminately ask for more memory if we have
// unused pages already available.
return(UIntPtr.Zero);
}
if (this.reserveLimit == UIntPtr.Zero)
{
// A collection occurred, so there is no region to extend
PageManager.ReleaseUnusedPages(startPage, pageCount,
fCleanPages);
return(UIntPtr.Zero);
}
BaseCollector.IncrementNewBytesSinceGC(paddedNeed);
this.allocNew = this.reserveLimit;
// Pad alignment space if necessary. NB: a prior call to
// AllocateFast may have started generating alignment tokens,
// but we may need to finish the job here if the residual space
// was insufficient for a multi-word alignment.
UIntPtr oldReserveLimit = this.reserveLimit;
this.reserveLimit += paddedNeed;
this.allocPtr =
Allocator.AlignedAllocationPtr(this.allocPtr,
this.reserveLimit,
alignment);
if (this.zeroedLimit < this.allocPtr)
{
this.zeroedLimit = this.allocPtr;
}
UIntPtr objectAddr = this.allocPtr + PreHeader.Size;
this.allocPtr += bytes;
if (fCleanPages)
{
if (this.zeroedLimit < oldReserveLimit)
{
Util.MemClear(this.zeroedLimit,
oldReserveLimit - this.zeroedLimit);
}
this.zeroedLimit = this.reserveLimit;
}
else
{
Util.MemClear(this.zeroedLimit,
this.allocPtr - this.zeroedLimit);
this.zeroedLimit = this.allocPtr;
}
VTable.Assert(this.allocPtr <= this.zeroedLimit);
VTable.Assert(PageTable.PageAligned(this.reserveLimit));
if (objectAddr >= oldReserveLimit)
{
// Object is first on new page
InteriorPtrTable.SetFirst(objectAddr);
}
else if (objectAddr + bytes < this.reserveLimit)
{
// The object does not end on new limit
// N.B. The next object may not be allocated at exactly
// (objectAddr + bytes) due to alignment considerations. It
// also might not ever be allocated. These cases are handled
// by InteriorPtrTable.First skipping over alignment tokens
// and callers of First watching out for unused space tokens.
InteriorPtrTable.SetFirst(objectAddr + bytes);
}
// We know an object is located as the last one in a page
// when it extends through the page to the next.
// Otherwise, it is totally before or below the page, and
// we are not sure whether it is the last object or not.
// So record only such an object for the last card in that
// page. Many objects may have been omitted due to
// this coarse-grain recording. But we should be able
// to incrementally update the offset table and find them.
// I believe this is a better choice than simply recording
// any object to the offset table, because most objects
// may just die and need not to record.
#if !SINGULARITY || SEMISPACE_COLLECTOR || ADAPTIVE_COPYING_COLLECTOR || SLIDING_COLLECTOR
if (GC.remsetType == RemSetType.Cards)
{
if (objectAddr < oldReserveLimit &&
allocPtr + bytes > oldReserveLimit)
{
#if DONT_RECORD_OBJALLOC_IN_OFFSETTABLE
#else
OffsetTable.SetLast(objectAddr);
#endif
}
}
#endif
#if SINGULARITY_KERNEL
Kernel.Waypoint(701);
#endif
return(objectAddr);
}
