public static unsafe void AddExceptionHandlerInfo(
void *handlerPtr,
void *filterPtr)
{
if (State == null)
{
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! ExceptionMethods.State is null.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
}
AddExceptionHandlerInfo_EntryStackState *BasePtr = (AddExceptionHandlerInfo_EntryStackState *)BasePointer;
uint LocalsSize = (uint)BasePtr - (uint)StackPointer;
// Create space for setting up handler info
StackPointer -= sizeof(ExceptionHandlerInfo);
// Setup handler info
ExceptionHandlerInfo *ExHndlrPtr = (ExceptionHandlerInfo *)StackPointer;
ExHndlrPtr->EBP = BasePtr->EBP;
// EBP + 8 (for ret addr, ebp) + 8 (for args) - sizeof(ExceptionHandlerInfo)
ExHndlrPtr->ESP = (uint)BasePtr + 8 + 8 - (uint)sizeof(ExceptionHandlerInfo);
ExHndlrPtr->FilterAddress = (byte *)filterPtr;
ExHndlrPtr->HandlerAddress = (byte *)handlerPtr;
ExHndlrPtr->PrevHandlerPtr = State->CurrentHandlerPtr;
ExHndlrPtr->InHandler = 0;
ExHndlrPtr->ExPending = 0;
ExHndlrPtr->Ex = null;
State->CurrentHandlerPtr = (ExceptionHandlerInfo *)((byte *)ExHndlrPtr + (LocalsSize + 12));
StackPointer -= 8; // For duplicate (empty) args
StackPointer -= 8; // For duplicate ebp, ret addr
// Setup the duplicate stack data
// - Nothing to do for args - duplicate values don't matter
// - Copy over ebp and return address
uint *DuplicateValsStackPointer = (uint *)StackPointer;
*DuplicateValsStackPointer = BasePtr->EBP;
*(DuplicateValsStackPointer + 1) = BasePtr->RetAddr;
ShiftStack((byte *)ExHndlrPtr + sizeof(ExceptionHandlerInfo) - 4, LocalsSize + 12);
// Shift stack pointer to correct position - eliminates "empty space" of duplicates
StackPointer += 16;
// MethodEnd will:
// - Add size of locals to esp
// - Pop EBP
// - Ret to ret address
// Caller will:
// - Add size of args to esp
// Which should leave the stack at the bottom of the (shifted up) ex handler info
}
public static void *NewObj(Testing2.Type theType)
{
if (!Enabled)
{
BasicConsole.SetTextColour(BasicConsole.warning_colour);
BasicConsole.WriteLine("Warning! GC returning null pointer because GC not enabled.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
}
//try
//{
InsideGC = true;
//Alloc space for GC header that prefixes object data
//Alloc space for new object
uint totalSize = theType.Size;
totalSize += (uint)sizeof(GCHeader);
GCHeader *newObjPtr = (GCHeader *)Heap.AllocZeroed(totalSize, "GC : NewObject");
if ((UInt32)newObjPtr == 0)
{
InsideGC = false;
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! GC can't create a new object because the heap returned a null pointer.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
}
NumObjs++;
//Initialise the GCHeader
SetSignature(newObjPtr);
newObjPtr->RefCount = 1;
//Initialise the object _Type field
Testing2.ObjectWithType newObj = (Testing2.ObjectWithType)Utilities.ObjectUtilities.GetObject(newObjPtr + 1);
newObj._Type = theType;
//Move past GCHeader
byte *newObjBytePtr = (byte *)(newObjPtr + 1);
InsideGC = false;
return(newObjBytePtr);
//}
//finally
//{
//}
}
public static unsafe void HandleEndFinally()
{
if (State == null ||
State->CurrentHandlerPtr == null)
{
// If we get to here, it's an unhandled exception
HaltReason = "Cannot end finally on null handler!";
BasicConsole.WriteLine(HaltReason);
BasicConsole.DelayOutput(5);
// Try to cause fault
*((byte *)0xDEADBEEF) = 0;
}
// Leaving a "finally" critical section cleanly
// We need to handle 2 cases:
// Case 1 : Pending exception
// Case 2 : No pending exception
if (State->CurrentHandlerPtr->ExPending != 0)
{
// Case 1 : Pending exception
HandleException();
}
else
{
// Case 2 : No pending exception
State->CurrentHandlerPtr->InHandler = 0;
uint EBP = State->CurrentHandlerPtr->EBP;
uint ESP = State->CurrentHandlerPtr->ESP;
State->CurrentHandlerPtr = State->CurrentHandlerPtr->PrevHandlerPtr;
ArbitaryReturn(EBP,
ESP + (uint)sizeof(ExceptionHandlerInfo),
(byte *)*((uint *)(BasePointer + 4)));
}
}
public static void _IncrementRefCount(byte *objPtr)
{
if ((uint)objPtr < (uint)sizeof(GCHeader))
{
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! GC can't increment ref count of an object in low memory.");
BasicConsole.DelayOutput(5);
BasicConsole.SetTextColour(BasicConsole.default_colour);
}
objPtr -= sizeof(GCHeader);
GCHeader *gcHeaderPtr = (GCHeader *)objPtr;
if (CheckSignature(gcHeaderPtr))
{
gcHeaderPtr->RefCount++;
if (gcHeaderPtr->RefCount > 0)
{
RemoveObjectToCleanup(gcHeaderPtr);
}
}
}
public static void _DecrementRefCount(byte *objPtr)
{
if ((uint)objPtr < (uint)sizeof(GCHeader))
{
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! GC can't decrement ref count of an object in low memory.");
BasicConsole.DelayOutput(5);
BasicConsole.SetTextColour(BasicConsole.default_colour);
}
GCHeader *gcHeaderPtr = (GCHeader *)(objPtr - sizeof(GCHeader));
if (CheckSignature(gcHeaderPtr))
{
gcHeaderPtr->RefCount--;
//If the ref count goes below 0 then there was a circular reference somewhere.
// In actuality we don't care we can just only do cleanup when the ref count is
// exactly 0.
if (gcHeaderPtr->RefCount == 0)
{
#if GC_TRACE
BasicConsole.WriteLine("Cleaned up object.");
#endif
Testing2.Object obj = (Testing2.Object)Utilities.ObjectUtilities.GetObject(objPtr);
if (obj is Testing2.Array)
{
//Decrement ref count of elements
Testing2.Array arr = (Testing2.Array)obj;
if (!arr.elemType.IsValueType)
{
Testing2.Object[] objArr = (Testing2.Object[])Utilities.ObjectUtilities.GetObject(objPtr);
for (int i = 0; i < arr.length; i++)
{
DecrementRefCount(objArr[i], true);
}
}
}
//Cleanup fields
FieldInfo *FieldInfoPtr = obj._Type.FieldTablePtr;
//Loop through all fields. The if-block at the end handles moving to parent
// fields.
while (FieldInfoPtr != null)
{
if (FieldInfoPtr->Size > 0)
{
Testing2.Type fieldType = (Testing2.Type)Utilities.ObjectUtilities.GetObject(FieldInfoPtr->FieldType);
if (!fieldType.IsValueType &&
!fieldType.IsPointer)
{
byte * fieldPtr = objPtr + FieldInfoPtr->Offset;
Testing2.Object theFieldObj = (Testing2.Object)Utilities.ObjectUtilities.GetObject(fieldPtr);
DecrementRefCount(theFieldObj, true);
#if GC_TRACE
BasicConsole.WriteLine("Cleaned up field.");
#endif
}
FieldInfoPtr++;
}
if (FieldInfoPtr->Size == 0)
{
FieldInfoPtr = (FieldInfo *)FieldInfoPtr->FieldType;
}
}
AddObjectToCleanup(gcHeaderPtr, objPtr);
}
}
}
public static void *NewString(int length)
{
if (!Enabled)
{
BasicConsole.SetTextColour(BasicConsole.warning_colour);
BasicConsole.WriteLine("Warning! GC returning null pointer because GC not enabled.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
}
//try
{
if (length < 0)
{
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! GC can't create a new string because \"length\" is less than 0.");
BasicConsole.DelayOutput(5);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
//ExceptionMethods.Throw_OverflowException();
}
InsideGC = true;
//Alloc space for GC header that prefixes object data
//Alloc space for new string object
//Alloc space for new string chars
uint totalSize = ((Testing2.Type) typeof(Testing2.String)).Size;
totalSize += /*char size in bytes*/ 2 * (uint)length;
totalSize += (uint)sizeof(GCHeader);
GCHeader *newObjPtr = (GCHeader *)Heap.AllocZeroed(totalSize, "GC : NewString");
if ((UInt32)newObjPtr == 0)
{
InsideGC = false;
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! GC can't create a new string because the heap returned a null pointer.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
}
NumObjs++;
NumStrings++;
//Initialise the GCHeader
SetSignature(newObjPtr);
//RefCount to 0 initially because of Testing2.String.New should be used
// - In theory, New should be called, creates new string and passes it back to caller
// Caller is then required to store the string in a variable resulting in inc.
// ref count so ref count = 1 in only stored location.
// Caller is not allowed to just "discard" (i.e. use Pop IL op or C# that generates
// Pop IL op) so ref count will always at some point be incremented and later
// decremented by managed code. OR the variable will stay in a static var until
// the OS exits...
newObjPtr->RefCount = 0;
Testing2.String newStr = (Testing2.String)Utilities.ObjectUtilities.GetObject(newObjPtr + 1);
newStr._Type = (Testing2.Type) typeof(Testing2.String);
newStr.length = length;
//Move past GCHeader
byte *newObjBytePtr = (byte *)(newObjPtr + 1);
InsideGC = false;
return(newObjBytePtr);
}
//finally
{
//ExitCritical();
}
}
public static void *NewArr(int length, Testing2.Type elemType)
{
if (!Enabled)
{
BasicConsole.SetTextColour(BasicConsole.warning_colour);
BasicConsole.WriteLine("Warning! GC returning null pointer because GC not enabled.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
}
//try
{
if (length < 0)
{
UART.Write("length < 0. Overflow exception.");
return(null);
//ExceptionMethods.Throw_OverflowException();
}
InsideGC = true;
//Alloc space for GC header that prefixes object data
//Alloc space for new array object
//Alloc space for new array elems
uint totalSize = ((Testing2.Type) typeof(Testing2.Array)).Size;
if (elemType.IsValueType)
{
totalSize += elemType.Size * (uint)length;
}
else
{
totalSize += elemType.StackSize * (uint)length;
}
totalSize += (uint)sizeof(GCHeader);
GCHeader *newObjPtr = (GCHeader *)Heap.AllocZeroed(totalSize, "GC : NewArray");
if ((UInt32)newObjPtr == 0)
{
InsideGC = false;
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("Error! GC can't create a new array because the heap returned a null pointer.");
BasicConsole.DelayOutput(10);
BasicConsole.SetTextColour(BasicConsole.default_colour);
return(null);
}
NumObjs++;
//Initialise the GCHeader
SetSignature(newObjPtr);
newObjPtr->RefCount = 1;
Testing2.Array newArr = (Testing2.Array)Utilities.ObjectUtilities.GetObject(newObjPtr + 1);
newArr._Type = (Testing2.Type) typeof(Testing2.Array);
newArr.length = length;
newArr.elemType = elemType;
//Move past GCHeader
byte *newObjBytePtr = (byte *)(newObjPtr + 1);
InsideGC = false;
return(newObjBytePtr);
}
//finally
{
}
}
public static unsafe void HandleLeave(void *continuePtr)
{
if (State == null ||
State->CurrentHandlerPtr == null)
{
// If we get to here, it's an unhandled exception
HaltReason = "Cannot leave on null handler! Address: 0x ";
uint y = *((uint *)(BasePointer + 4));
int offset = 48;
#region Address
while (offset > 40)
{
uint rem = y & 0xFu;
switch (rem)
{
case 0:
HaltReason[offset] = '0';
break;
case 1:
HaltReason[offset] = '1';
break;
case 2:
HaltReason[offset] = '2';
break;
case 3:
HaltReason[offset] = '3';
break;
case 4:
HaltReason[offset] = '4';
break;
case 5:
HaltReason[offset] = '5';
break;
case 6:
HaltReason[offset] = '6';
break;
case 7:
HaltReason[offset] = '7';
break;
case 8:
HaltReason[offset] = '8';
break;
case 9:
HaltReason[offset] = '9';
break;
case 10:
HaltReason[offset] = 'A';
break;
case 11:
HaltReason[offset] = 'B';
break;
case 12:
HaltReason[offset] = 'C';
break;
case 13:
HaltReason[offset] = 'D';
break;
case 14:
HaltReason[offset] = 'E';
break;
case 15:
HaltReason[offset] = 'F';
break;
}
y >>= 4;
offset--;
}
#endregion
BasicConsole.WriteLine(HaltReason);
BasicConsole.DelayOutput(5);
// Try to cause fault
*((byte *)0xDEADBEEF) = 0;
}
// Leaving a critical section cleanly
// We need to handle 2 cases:
// Case 1 : Leaving "try" or "catch" of a try-catch
// Case 2 : Leaving the "try" of a try-finally
if ((uint)State->CurrentHandlerPtr->FilterAddress != 0x0u)
{
// Case 1 : Leaving "try" or "catch" of a try-catch
if (State->CurrentHandlerPtr->Ex != null)
{
Testing2.GC.DecrementRefCount((Testing2.Object)Utilities.ObjectUtilities.GetObject(State->CurrentHandlerPtr->Ex));
State->CurrentHandlerPtr->Ex = null;
}
State->CurrentHandlerPtr->InHandler = 0;
uint EBP = State->CurrentHandlerPtr->EBP;
uint ESP = State->CurrentHandlerPtr->ESP;
State->CurrentHandlerPtr = State->CurrentHandlerPtr->PrevHandlerPtr;
ArbitaryReturn(EBP, ESP + (uint)sizeof(ExceptionHandlerInfo), (byte *)continuePtr);
}
else
{
// Case 2 : Leaving the "try" of a try-finally
State->CurrentHandlerPtr->InHandler = 1;
ArbitaryReturn(State->CurrentHandlerPtr->EBP,
State->CurrentHandlerPtr->ESP,
State->CurrentHandlerPtr->HandlerAddress);
}
}
public static void *Alloc(UInt32 size, UInt32 boundary, Testing2.String caller)
{
#if HEAP_TRACE
BasicConsole.SetTextColour(BasicConsole.warning_colour);
BasicConsole.WriteLine("Attempt to alloc mem....");
BasicConsole.SetTextColour(BasicConsole.default_colour);
#endif
HeapBlock *b;
byte * bm;
UInt32 bcnt;
UInt32 x, y, z;
UInt32 bneed;
byte nid;
if (boundary > 1)
{
size += (boundary - 1);
}
/* iterate blocks */
for (b = fblock; (UInt32)b != 0; b = b->next)
{
/* check if block has enough room */
if (b->size - (b->used * b->bsize) >= size)
{
bcnt = b->size / b->bsize;
bneed = (size / b->bsize) * b->bsize < size ? size / b->bsize + 1 : size / b->bsize;
bm = (byte *)&b[1];
for (x = (b->lfb + 1 >= bcnt ? 0 : b->lfb + 1); x != b->lfb; ++x)
{
/* just wrap around */
if (x >= bcnt)
{
x = 0;
}
if (bm[x] == 0)
{
/* count free blocks */
for (y = 0; bm[x + y] == 0 && y < bneed && (x + y) < bcnt; ++y)
{
;
}
/* we have enough, now allocate them */
if (y == bneed)
{
/* find ID that does not match left or right */
nid = GetNID(bm[x - 1], bm[x + y]);
/* allocate by setting id */
for (z = 0; z < y; ++z)
{
bm[x + z] = nid;
}
/* optimization */
b->lfb = (x + bneed) - 2;
/* count used blocks NOT bytes */
b->used += y;
void *result = (void *)(x * b->bsize + (UInt32)(&b[1]));
if (boundary > 1)
{
result = (void *)((((UInt32)result) + (boundary - 1)) & ~(boundary - 1));
#if HEAP_TRACE
ExitCritical();
BasicConsole.WriteLine(((Testing2.String) "Allocated address ") + (uint)result + " on boundary " + boundary + " for " + caller);
EnterCritical("Alloc:Boundary condition");
#endif
}
return(result);
}
/* x will be incremented by one ONCE more in our FOR loop */
x += (y - 1);
continue;
}
}
}
}
#if HEAP_TRACE
BasicConsole.SetTextColour(BasicConsole.error_colour);
BasicConsole.WriteLine("!!Heap out of memory!!");
BasicConsole.SetTextColour(BasicConsole.default_colour);
BasicConsole.DelayOutput(2);
#endif
return(null);
}
