protected override void WriteImplByRef(ref Object location,
Object value,
int mask)
{
CMSMarking.ReferenceCheck(ref location, value, mask);
location = value;
}
protected override void WriteImpl(UIntPtr *location,
Object value,
int mask)
{
CMSMarking.ReferenceCheck(location, value, mask);
*location = Magic.addressOf(value);
}
protected override Object AtomicCompareAndSwapImpl(ref Object loc,
Object newVal,
Object comp,
int mask)
{
CMSMarking.ReferenceCheck(ref loc, newVal, 0);
newVal = ForwardNullable(newVal);
for (;;)
{
Object oldVal = loc;
Object commitVal;
if (oldVal == comp ||
ForwardNullable(oldVal) == ForwardNullable(comp))
{
commitVal = newVal;
}
else
{
// still CAS but only to get a memory barrier
commitVal = oldVal;
}
if (Interlocked.CompareExchange(ref loc,
commitVal, oldVal)
== oldVal)
{
return(oldVal);
}
}
}
internal static void Mark(UIntPtr ptr)
{
if (CMSMarking.MarkIfNecessary(ptr) &&
fVerifyToSpaceMark &&
ptr != UIntPtr.Zero &&
!instance.IsInToSpace(ptr))
{
VTable.DebugBreak();
}
}
protected override Object AtomicSwapImpl(ref Object reference,
Object value,
int mask)
{
CMSMarking.ReferenceCheck(ref reference, value, mask);
UIntPtr resultAddr =
Interlocked.Exchange(Magic.toPointer(ref reference),
Magic.addressOf(value));
return(Magic.fromAddress(resultAddr));
}
Object AtomicCompareAndSwapImpl(ref Object reference,
Object newValue,
Object comparand,
int mask)
{
CMSMarking.ReferenceCheck(ref reference, newValue, mask);
UIntPtr resultAddr =
Interlocked.CompareExchange(Magic.toPointer(ref reference),
Magic.addressOf(newValue),
Magic.addressOf(comparand));
return(Magic.fromAddress(resultAddr));
}