// The primitive handles PositionableStream>>atEnd, but only for arrays/strings // Does not use successFlag. Unary, so does not modify the stack pointer BOOL __fastcall Interpreter::primitiveAtEnd() { PosStreamOTE* streamPointer = reinterpret_cast<PosStreamOTE*>(stackTop()); // Access receiver //ASSERT(!ObjectMemoryIsIntegerObject(streamPointer) && ObjectMemory::isKindOf(streamPointer, Pointers.ClassPositionableStream)); PositionableStream* readStream = streamPointer->m_location; // Ensure valid stream (see BBB p632) if (!ObjectMemoryIsIntegerObject(readStream->m_index) || !ObjectMemoryIsIntegerObject(readStream->m_readLimit)) return primitiveFailure(0); SMALLINTEGER index = ObjectMemoryIntegerValueOf(readStream->m_index); SMALLINTEGER limit = ObjectMemoryIntegerValueOf(readStream->m_readLimit); BehaviorOTE* bufClass = readStream->m_array->m_oteClass; OTE* boolResult; if (bufClass == Pointers.ClassString || bufClass == Pointers.ClassByteArray) boolResult = index >= limit || (MWORD(index) >= readStream->m_array->bytesSize()) ? Pointers.True : Pointers.False; else if (bufClass == Pointers.ClassArray) boolResult = index >= limit || (MWORD(index) >= readStream->m_array->pointersSize()) ? Pointers.True : Pointers.False; else return primitiveFailure(1); // Doesn't work for non-Strings/ByteArrays/Arrays, or if out of bounds stackTop() = reinterpret_cast<Oop>(boolResult); return primitiveSuccess(); }
Oop* Interpreter::primitiveCopyFromTo(Oop* const sp, unsigned) { Oop oopToArg = *sp; Oop oopFromArg = *(sp - 1); OTE* oteReceiver = reinterpret_cast<OTE*>(*(sp - 2)); if (ObjectMemoryIsIntegerObject(oopToArg) && ObjectMemoryIsIntegerObject(oopFromArg)) { SMALLINTEGER from = ObjectMemoryIntegerValueOf(oopFromArg); SMALLINTEGER to = ObjectMemoryIntegerValueOf(oopToArg); if (from > 0) { SMALLINTEGER count = to - from + 1; if (count >= 0) { OTE* oteAnswer = ObjectMemory::CopyElements(oteReceiver, from - 1, count); if (oteAnswer != nullptr) { *(sp - 2) = (Oop)oteAnswer; ObjectMemory::AddToZct(oteAnswer); return sp - 2; } } } // Bounds error return primitiveFailure(1); } else { // Non-SmallInteger from and/or to return primitiveFailure(0); } }
// Locate the next occurrence of the given character in the receiver between the specified indices. BOOL __fastcall Interpreter::primitiveStringNextIndexOfFromTo() { Oop integerPointer = stackTop(); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(0); // to not an integer const SMALLINTEGER to = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(1); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(1); // from not an integer SMALLINTEGER from = ObjectMemoryIntegerValueOf(integerPointer); Oop valuePointer = stackValue(2); StringOTE* receiverPointer = reinterpret_cast<StringOTE*>(stackValue(3)); Oop answer = ZeroPointer; if ((ObjectMemory::fetchClassOf(valuePointer) == Pointers.ClassCharacter) && to >= from) { ASSERT(!receiverPointer->isPointers()); // Search a byte object const SMALLINTEGER length = receiverPointer->bytesSize(); // We can only be in here if to>=from, so if to>=1, then => from >= 1 // furthermore if to <= length then => from <= length if (from < 1 || to > length) return primitiveFailure(2); // Search is in bounds, lets do it CharOTE* oteChar = reinterpret_cast<CharOTE*>(valuePointer); Character* charObj = oteChar->m_location; const char charValue = static_cast<char>(ObjectMemoryIntegerValueOf(charObj->m_asciiValue)); String* chars = receiverPointer->m_location; from--; while (from < to) { if (chars->m_characters[from++] == charValue) { answer = ObjectMemoryIntegerObjectOf(from); break; } } } stackValue(3) = answer; pop(3); return primitiveSuccess(); }
VariantObject* ObjectMemory::resize(PointersOTE* ote, MWORD newPointers, bool bRefCount) { ASSERT(!ObjectMemoryIsIntegerObject(ote) && ote->isPointers()); VariantObject* pObj = ote->m_location; const MWORD oldPointers = ote->pointersSize(); // If resizing the active process, then we don't do any ref. counting as refs from // the current stack are not counted (we used deferred ref. counting) if (bRefCount) { for (MWORD i=newPointers;i<oldPointers;i++) countDown(pObj->m_fields[i]); } // Reallocate the object to the new size (bigger or smaller) pObj = reinterpret_cast<VariantObject*>(basicResize(reinterpret_cast<POTE>(ote), SizeOfPointers(newPointers), 0)); if (pObj) { ASSERT(newPointers == ote->pointersSize()); newPointers = ote->pointersSize(); // Initialize any new pointers to Nil (indices must fit in a SmallInteger) const Oop nil = Oop(Pointers.Nil); for (MWORD i=oldPointers; i<newPointers; i++) pObj->m_fields[i] = nil; } return pObj; }
// Uses object identity to locate the next occurrence of the argument in the receiver from // the specified index to the specified index Oop* __fastcall Interpreter::primitiveStringSearch() { Oop* const sp = m_registers.m_stackPointer; Oop integerPointer = *sp; if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(0); // startingAt not an integer const SMALLINTEGER startingAt = ObjectMemoryIntegerValueOf(integerPointer); Oop oopSubString = *(sp-1); BytesOTE* oteReceiver = reinterpret_cast<BytesOTE*>(*(sp-2)); if (ObjectMemory::fetchClassOf(oopSubString) != oteReceiver->m_oteClass) return primitiveFailure(2); // We know it can't be a SmallInteger because it has the same class as the receiver BytesOTE* oteSubString = reinterpret_cast<BytesOTE*>(oopSubString); VariantByteObject* bytesPattern = oteSubString->m_location; VariantByteObject* bytesReceiver = oteReceiver->m_location; const int M = oteSubString->bytesSize(); const int N = oteReceiver->bytesSize(); // Check 'startingAt' is in range if (startingAt < 1 || startingAt > N) return primitiveFailure(1); // out of bounds int nOffset = M == 0 || ((startingAt + M) - 1 > N) ? -1 : stringSearch(bytesReceiver->m_fields, N, bytesPattern->m_fields, M, startingAt - 1); *(sp-2) = ObjectMemoryIntegerObjectOf(nOffset+1); return sp-2; }
// Callback proc for MM timers // N.B. This routine is called from a separate thread (in Win32), rather than in // interrupt time, but careful coding is still important. The recommended // list of routines is limited to: // EnterCriticalSection ReleaseSemaphore // LeaveCriticalSection SetEvent // timeGetSystemTime timeGetTime // OutputDebugString timeKillEvent // PostMessage timeSetEvent // // "If a Win32 low-level audio callback [we are using mm timers here] shares data // with other code, a Critical Section or similar mutual exclusion mechanism should // be used to protect the integrity of the data". // Access to the asynchronous semaphore array is protected by a critical section // in the asynchronousSignal and CheckProcessSwitch routines. We don't really care // that much about the timerID void CALLBACK Interpreter::TimeProc(UINT uID, UINT /*uMsg*/, DWORD /*dwUser*/, DWORD /*dw1*/, DWORD /*dw2*/) { // Avoid firing a timer which has been cancelled (or is about to be cancelled!) // We use an InterlockedExchange() to set the value to 0 so that the main thread // can recognise that the timer has fired without race conditions if (_InterlockedExchange(reinterpret_cast<SHAREDLONG*>(&timerID), 0) != 0) { // If not previously killed (which is very unlikely except in certain exceptional // circumstances where the timer is killed at the exact moment it is about to fire) // then go ahead and signal the semaphore and the wakeup event // We mustn't access Pointers from an async thread when object memory is compacting // as the Pointer will be wrong GrabAsyncProtect(); SemaphoreOTE* timerSemaphore = Pointers.TimingSemaphore; HARDASSERT(!ObjectMemoryIsIntegerObject(timerSemaphore)); HARDASSERT(!timerSemaphore->isFree()); HARDASSERT(timerSemaphore->m_oteClass == Pointers.ClassSemaphore); // Asynchronously signal the required semaphore asynchronously, which will be detected // in sync. with the dispatching of byte codes, and properly signalled asynchronousSignalNoProtect(timerSemaphore); // Signal the timing Event, in case the idle process has put the VM to sleep SetWakeupEvent(); RelinquishAsyncProtect(); } else // An old timer (which should have been cancelled) has fired trace("Old timer %d fired, current %d\n", uID, timerID); }
VariantByteObject* ObjectMemory::resize(BytesOTE* ote, MWORD newByteSize) { ASSERT(!ObjectMemoryIsIntegerObject(ote) && ote->isBytes()); MWORD totalByteSize = newByteSize + SizeOfPointers(0); // Add header size VariantByteObject* pByteObj = ote->m_location; MWORD oldByteSize = ote->getSize(); if (ote->isNullTerminated()) { pByteObj = reinterpret_cast<VariantByteObject*>(ObjectMemory::basicResize(reinterpret_cast<POTE>(ote), totalByteSize, 1)); ASSERT(pByteObj); // Null-terminated objects should always be resizeable // Ensure we have a null-terminator reinterpret_cast<BYTE*>(pByteObj)[totalByteSize] = 0; } else pByteObj = reinterpret_cast<VariantByteObject*>(ObjectMemory::basicResize(reinterpret_cast<POTE>(ote), totalByteSize, 0)); if (pByteObj && totalByteSize > oldByteSize) { // The object grew, so ensure it is properly initialized memset(reinterpret_cast<BYTE*>(pByteObj)+oldByteSize, 0, totalByteSize-oldByteSize); } return pByteObj; }
// This primitive handles PositionableStream>>nextSDWORD, but only for byte-arrays // Unary message, so does not modify stack pointer BOOL __fastcall Interpreter::primitiveNextSDWORD() { PosStreamOTE* streamPointer = reinterpret_cast<PosStreamOTE*>(stackTop()); // Access receiver PositionableStream* readStream = streamPointer->m_location; // Ensure valid stream - unusually this validity check is included in the Blue Book spec // and appears to be implemented in most Smalltalks, so we implement here too. if (!ObjectMemoryIsIntegerObject(readStream->m_index) || !ObjectMemoryIsIntegerObject(readStream->m_readLimit)) return primitiveFailure(0); // Receiver fails invariant check SMALLINTEGER index = ObjectMemoryIntegerValueOf(readStream->m_index); SMALLINTEGER limit = ObjectMemoryIntegerValueOf(readStream->m_readLimit); // Is the current index within the limits of the collection? // Remember that the index is 1 based (it's a Smalltalk index), and we're 0 based, // so we don't need to increment it until after we've got the next object if (index < 0 || index >= limit) return primitiveFailure(2); // No, fail it OTE* oteBuf = readStream->m_array; BehaviorOTE* bufClass = oteBuf->m_oteClass; if (bufClass != Pointers.ClassByteArray) return primitiveFailure(1); // Collection cannot be handled by primitive, rely on Smalltalk code ByteArrayOTE* oteBytes = reinterpret_cast<ByteArrayOTE*>(oteBuf); const int newIndex = index + sizeof(SDWORD); if (MWORD(newIndex) > oteBytes->bytesSize()) return primitiveFailure(3); const Oop oopNewIndex = ObjectMemoryIntegerObjectOf(newIndex); if (int(oopNewIndex) < 0) return primitiveFailure(4); // index overflowed SmallInteger range // When incrementing the index we must allow for it overflowing a SmallInteger, even though // this is extremely unlikely in practice readStream->m_index = oopNewIndex; // Receiver is overwritten ByteArray* byteArray = oteBytes->m_location; replaceStackTopWithNew(Integer::NewSigned32(*reinterpret_cast<SDWORD*>(byteArray->m_elements+index))); return primitiveSuccess(); // Succeed }
Oop* __fastcall Interpreter::primitivePerform(CompiledMethod& , unsigned argCount) { SymbolOTE* performSelector = m_oopMessageSelector; // Save in case we need to restore SymbolOTE* selectorToPerform = reinterpret_cast<SymbolOTE*>(stackValue(argCount-1)); if (ObjectMemoryIsIntegerObject(selectorToPerform)) return primitiveFailure(1); m_oopMessageSelector = selectorToPerform; Oop newReceiver = stackValue(argCount); // lookupMethodInClass returns the Oop of the new CompiledMethod // if the selector is found, or Pointers.DoesNotUnderstand if the class // does not understand the selector. We succeed if either the argument // count of the returned method matches that passed to this primitive, // or if the selector is not understood, because by this time the // detection of the 'does not understand' will have triggered // the create of a Message object (see createActualMessage) into // which all the arguments will have been moved, and which then replaces // those arguments on the Smalltalk context stack. i.e. the primitive // will succeed if the message is not understood, but will result in // the execution of doesNotUnderstand: rather than the selector we've // been asked to perform. This works because // after a doesNotUnderstand detection, the stack has a Message at stack // top, the selector is still there, and argCount is now 1. Consequently // the Message gets shuffled over the selector, and doesNotUnderstand is // sent MethodOTE* methodPointer = findNewMethodInClass(ObjectMemory::fetchClassOf(newReceiver), (argCount-1)); CompiledMethod* method = methodPointer->m_location; if (method->m_header.argumentCount == (argCount-1) || m_oopMessageSelector == Pointers.DoesNotUnderstandSelector) { // Shuffle arguments down over the selector (use argumentCount of // method found which may not equal argCount) const unsigned methodArgCount = method->m_header.argumentCount; // #pragma message("primitivePerform: Instead of shuffling args down 1, why not just deduct 1 from calling frames suspended SP after exec?") Oop* const sp = m_registers.m_stackPointer - methodArgCount; // We don't need to count down the overwritten oop anymore, since we don't ref. count stack ops // Not worth overhead of calling memmove here since argumentCount // normally small for (unsigned i=0;i<methodArgCount;i++) sp[i] = sp[i+1]; popStack(); executeNewMethod(methodPointer, methodArgCount); return primitiveSuccess(0); } else { // The argument count did not match, so drop out into the Smalltalk // having restored the selector ASSERT(m_oopMessageSelector!=Pointers.DoesNotUnderstandSelector); m_oopMessageSelector = performSelector; return primitiveFailure(0); } }
// Answer a new process with an initial stack size specified by the first argument, and a maximum // stack size specified by the second argument. Oop* __fastcall Interpreter::primitiveNewVirtual(Oop* const sp, unsigned) { Oop maxArg = *sp; SMALLINTEGER maxSize; if (ObjectMemoryIsIntegerObject(maxArg) && (maxSize = ObjectMemoryIntegerValueOf(maxArg)) >= 0) { Oop initArg = *(sp - 1); SMALLINTEGER initialSize; if (ObjectMemoryIsIntegerObject(initArg) && (initialSize = ObjectMemoryIntegerValueOf(initArg)) >= 0) { BehaviorOTE* receiverClass = reinterpret_cast<BehaviorOTE*>(*(sp - 2)); InstanceSpecification instSpec = receiverClass->m_location->m_instanceSpec; if (instSpec.m_indexable && !instSpec.m_nonInstantiable) { unsigned fixedFields = instSpec.m_fixedFields; VirtualOTE* newObject = ObjectMemory::newVirtualObject(receiverClass, initialSize + fixedFields, maxSize); if (newObject) { *(sp - 2) = reinterpret_cast<Oop>(newObject); // No point saving down SP before potential Zct reconcile as the init & max args must be SmallIntegers ObjectMemory::AddToZct((OTE*)newObject); return sp - 2; } else return primitiveFailure(4); // OOM } else { return primitiveFailure(instSpec.m_nonInstantiable ? 3 : 2); // Non-indexable or abstract class } } else { return primitiveFailure(1); // initialSize arg not a SmallInteger } } else { return primitiveFailure(0); // maxsize arg not a SmallInteger } }
inline void Interpreter::subclassWindow(OTE* window, HWND hWnd) { ASSERT(!ObjectMemoryIsIntegerObject(window)); // As this is called from an external entry point, we must ensure that OT/stack overflows // are handled, and also that we catch the SE_VMCALLBACKUNWIND exceptions __try { bool bDisabled = disableInterrupts(true); Oop retVal = performWith(Oop(window), Pointers.subclassWindowSymbol, Oop(ExternalHandle::New(hWnd))); ObjectMemory::countDown(retVal); ASSERT(m_bInterruptsDisabled); disableInterrupts(bDisabled); } __except (callbackExceptionFilter(GetExceptionInformation())) { trace("WARNING: Unwinding Interpreter::subclassWindow(%#x, %#x)\n", window, hWnd); } }
BOOL __fastcall Interpreter::primitiveSnapshot(CompiledMethod&, unsigned argCount) { Oop arg = stackValue(argCount - 1); char* szFileName; if (arg == Oop(Pointers.Nil)) szFileName = 0; else if (ObjectMemory::fetchClassOf(arg) == Pointers.ClassString) { StringOTE* oteString = reinterpret_cast<StringOTE*>(arg); String* fileName = oteString->m_location; szFileName = fileName->m_characters; } else return primitiveFailure(0); bool bBackup; if (argCount >= 2) bBackup = reinterpret_cast<OTE*>(stackValue(argCount - 2)) == Pointers.True; else bBackup = false; SMALLINTEGER nCompressionLevel; if (argCount >= 3) { Oop oopCompressionLevel = stackValue(argCount - 3); nCompressionLevel = ObjectMemoryIsIntegerObject(oopCompressionLevel) ? ObjectMemoryIntegerValueOf(oopCompressionLevel) : 0; } else nCompressionLevel = 0; SMALLUNSIGNED nMaxObjects = 0; if (argCount >= 4) { Oop oopMaxObjects = stackValue(argCount - 4); if (ObjectMemoryIsIntegerObject(oopMaxObjects)) { nMaxObjects = ObjectMemoryIntegerValueOf(oopMaxObjects); } } // N.B. It is not necessary to clear down the memory pools as the free list is rebuild on every image // load and the pool members, though not on the free list at present, are marked as free entries // in the object table // ZCT is reconciled, so objects may be deleted flushAtCaches(); // Store the active frame of the active process before saving so available on image reload // We're not actually suspending the process now, but it appears like that to the snapshotted // image on restarting m_registers.PrepareToSuspendProcess(); #ifdef OAD DWORD timeStart = timeGetTime(); #endif int saveResult = ObjectMemory::SaveImageFile(szFileName, bBackup, nCompressionLevel, nMaxObjects); #ifdef OAD DWORD timeEnd = timeGetTime(); TRACESTREAM << "Time to save image: " << (timeEnd - timeStart) << " mS" << endl; #endif if (!saveResult) { // Success popStack(); return primitiveSuccess(); } else { // Failure return primitiveFailure(saveResult); } }
Oop* __fastcall Interpreter::primitivePerformWithArgs() { Oop* const sp = m_registers.m_stackPointer; ArrayOTE* argumentArray = reinterpret_cast<ArrayOTE*>(*(sp)); BehaviorOTE* arrayClass = ObjectMemory::fetchClassOf(Oop(argumentArray)); if (arrayClass != Pointers.ClassArray) return primitiveFailure(0); // N.B. We're using a large stack, so don't bother checking for overflow // (standard stack overflow mechanism should catch it) // We must not get the length outside, in case small integer arg const unsigned argCount = argumentArray->pointersSize(); // Save old message selector in case of prim failure (need to reinstate) SymbolOTE* performSelector = m_oopMessageSelector; // To ensure the argumentArray doesn't go away when we push its contents // onto the stack, in case we need it for recovery from an argument // count mismatch we leave its ref. count elevated SymbolOTE* selectorToPerform = reinterpret_cast<SymbolOTE*>(*(sp-1)); if (ObjectMemoryIsIntegerObject(selectorToPerform)) return primitiveFailure(1); m_oopMessageSelector = selectorToPerform; // Get selector from stack // Don't need to count down the stack ref. ASSERT(!selectorToPerform->isFree()); Oop newReceiver = *(sp-2); // receiver is under selector and arg array // Push the args from the array onto the stack. We must do this before // looking up the method, because if the receiver does not understand // the method then the lookup routines copy the arguments off the stack // into a Message object Array* args = argumentArray->m_location; for (MWORD i=0; i<argCount; i++) { Oop pushee = args->m_elements[i]; // Note no need to inc the ref. count when pushing on the stack sp[i-1] = pushee; } // Args written over top of selector and argument array (hence -2) m_registers.m_stackPointer = sp+argCount-2; // There is a subtle complication here when the receiver does not // understand the message, by which lookupMethodInClass() converts // the message we're trying to perform to a #doesNotUnderstand: with // all arguments moved to a Message. We still want to execute this // does not understand, so we also execute the method if the argument // counts do not match, but it was not understood. Note that it is // possible for a doesNotUnderstand: to be executed thru the first // test if the argumentArray contained only one argument. We allow // this to happen to avoid testing for not understood in the normal // case - just be aware of this anomaly. MethodOTE* methodPointer = findNewMethodInClass(ObjectMemory::fetchClassOf(newReceiver), argCount); CompiledMethod& method = *methodPointer->m_location; const unsigned methodArgCount = method.m_header.argumentCount; if (methodArgCount == argCount || m_oopMessageSelector == Pointers.DoesNotUnderstandSelector) { // WE no longer need the argument array, but don't count it down since we only have a stack ref. executeNewMethod(methodPointer, methodArgCount); return primitiveSuccess(0); } else { // Receiver must have understood the message, but we had wrong // number of arguments, so reinstate the stack and fail the primitive pop(argCount); pushObject((OTE*)m_oopMessageSelector); // Argument array already has artificially increased ref. count push(Oop(argumentArray)); m_oopMessageSelector = performSelector; return primitiveFailure(1); } }
// Uses object identity to locate the next occurrence of the argument in the receiver from // the specified index to the specified index Oop* __fastcall Interpreter::primitiveNextIndexOfFromTo() { Oop integerPointer = stackTop(); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(0); // to not an integer const SMALLINTEGER to = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(1); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(1); // from not an integer SMALLINTEGER from = ObjectMemoryIntegerValueOf(integerPointer); Oop valuePointer = stackValue(2); OTE* receiverPointer = reinterpret_cast<OTE*>(stackValue(3)); // #ifdef _DEBUG if (ObjectMemoryIsIntegerObject(receiverPointer)) return primitiveFailure(2); // Not valid for SmallIntegers // #endif Oop answer = ZeroPointer; if (to >= from) { if (!receiverPointer->isPointers()) { // Search a byte object BytesOTE* oteBytes = reinterpret_cast<BytesOTE*>(receiverPointer); if (ObjectMemoryIsIntegerObject(valuePointer))// Arg MUST be an Integer to be a member { const MWORD byteValue = ObjectMemoryIntegerValueOf(valuePointer); if (byteValue < 256) // Only worth looking for 0..255 { const SMALLINTEGER length = oteBytes->bytesSize(); // We can only be in here if to>=from, so if to>=1, then => from >= 1 // furthermore if to <= length then => from <= length if (from < 1 || to > length) return primitiveFailure(2); // Search is in bounds, lets do it VariantByteObject* bytes = oteBytes->m_location; from--; while (from < to) if (bytes->m_fields[from++] == byteValue) { answer = ObjectMemoryIntegerObjectOf(from); break; } } } } else { // Search a pointer object - but only the indexable vars PointersOTE* oteReceiver = reinterpret_cast<PointersOTE*>(receiverPointer); VariantObject* receiver = oteReceiver->m_location; Behavior* behavior = receiverPointer->m_oteClass->m_location; const MWORD length = oteReceiver->pointersSize(); const MWORD fixedFields = behavior->m_instanceSpec.m_fixedFields; // Similar reasoning with to/from as for byte objects, but here we need to // take account of the fixed fields. if (from < 1 || (to + fixedFields > length)) return primitiveFailure(2); // Out of bounds Oop* indexedFields = receiver->m_fields + fixedFields; from--; while (from < to) if (indexedFields[from++] == valuePointer) { answer = ObjectMemoryIntegerObjectOf(from); break; } } } else answer = ZeroPointer; // Range is non-inclusive, cannot be there stackValue(3) = answer; return primitiveSuccess(3); }
/* Implements String>>replaceFrom: start to: stop with: aString startingAt: startAt But is also used for ByteArray Does not use successFlag, and nils out argument (if successful) to leave a clean stack */ BOOL __fastcall Interpreter::primitiveStringReplace() { Oop integerPointer = stackTop(); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(0); SMALLINTEGER startAt = ObjectMemoryIntegerValueOf(integerPointer); OTE* argPointer = reinterpret_cast<OTE*>(stackValue(1)); integerPointer = stackValue(2); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(1); SMALLINTEGER stop = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(3); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(2); SMALLINTEGER start = ObjectMemoryIntegerValueOf(integerPointer); OTE* receiverPointer = reinterpret_cast<OTE*>(stackValue(4)); // Validity checks TODO("Try to do cleverer faster check here - too many (reproducing V behaviour)") // Only works for byte objects #ifdef _DEBUG if (!receiverPointer->isBytes()) return primitiveFailure(0); #else // Assume primitive used correctly - i.e. only in byte objects #endif if (ObjectMemoryIsIntegerObject(argPointer) || !argPointer->isBytes()) return primitiveFailure(3); // Empty move if stop before start, is considered valid regardless (strange but true) TODO("Change this so that does fail if stop or start < 1, only like this for V compatibility") if (stop >= start) { POBJECT receiverBytes = receiverPointer->m_location; // The receiver can be an indirect pointer (e.g. an instance of ExternalAddress) BYTE* pTo; Behavior* byteClass = receiverPointer->m_oteClass->m_location; if (byteClass->isIndirect()) pTo = static_cast<BYTE*>(static_cast<ExternalAddress*>(receiverBytes)->m_pointer); else { int length = receiverPointer->bytesSize(); // We can only be in here if stop>=start, so if start>=1, then => stop >= 1 // furthermore if stop <= length then => start <= length if (start < 1 || stop > length) return primitiveFailure(4); pTo = static_cast<ByteArray*>(receiverBytes)->m_elements; } POBJECT argBytes = argPointer->m_location; // The argument can also be an indirect pointer (e.g. an instance of ExternalAddress) BYTE* pFrom; Behavior* argClass = argPointer->m_oteClass->m_location; if (argClass->isIndirect()) pFrom = static_cast<BYTE*>(static_cast<ExternalAddress*>(argBytes)->m_pointer); else { int length = argPointer->bytesSize(); // We can only be in here if stop>=start, so => stop-start >= 0 // therefore if startAt >= 1 then => stopAt >= 1, for similar // reasons (since stopAt >= startAt) we don't need to test // that startAt <= length int stopAt = startAt+stop-start; if (startAt < 1 || stopAt > length) return primitiveFailure(4); pFrom = static_cast<ByteArray*>(argBytes)->m_elements; } // Remember that Smalltalk indices are 1 based // Might be overlapping memmove(pTo+start-1, pFrom+startAt-1, stop-start+1); } pop(4); return TRUE; }
// This is a double dispatched primitive which knows that the argument is a byte object (though // we still check this to avoid GPFs), and the receiver is guaranteed to be a byte object. e.g. // // aByteObject replaceBytesOf: anOtherByteObject from: start to: stop startingAt: startAt // BOOL __fastcall Interpreter::primitiveReplaceBytes() { Oop integerPointer = stackTop(); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(0); // startAt is not an integer SMALLINTEGER startAt = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(1); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(1); // stop is not an integer SMALLINTEGER stop = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(2); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(2); // start is not an integer SMALLINTEGER start = ObjectMemoryIntegerValueOf(integerPointer); OTE* argPointer = reinterpret_cast<OTE*>(stackValue(3)); if (ObjectMemoryIsIntegerObject(argPointer) || !argPointer->isBytes()) return primitiveFailure(3); // Argument MUST be a byte object // Empty move if stop before start, is considered valid regardless (strange but true) // this is the convention adopted by most implementations. if (stop >= start) { if (startAt < 1 || start < 1) return primitiveFailure(4); // Out-of-bounds // We still permit the argument to be an address to cut down on the number of primitives // and double dispatch methods we must implement (2 rather than 4) BYTE* pTo; Behavior* behavior = argPointer->m_oteClass->m_location; if (behavior->isIndirect()) { AddressOTE* oteBytes = reinterpret_cast<AddressOTE*>(argPointer); // We don't know how big the object is the argument points at, so cannot check length // against stop point pTo = static_cast<BYTE*>(oteBytes->m_location->m_pointer); } else { // We can test that we're not going to write off the end of the argument int length = argPointer->bytesSize(); // We can only be in here if stop>=start, so => stop-start >= 0 // therefore if startAt >= 1 then => stopAt >= 1, for similar // reasons (since stopAt >= startAt) we don't need to test // that startAt <= length if (stop > length) return primitiveFailure(4); // Bounds error VariantByteObject* argBytes = reinterpret_cast<BytesOTE*>(argPointer)->m_location; pTo = argBytes->m_fields; } BytesOTE* receiverPointer = reinterpret_cast<BytesOTE*>(stackValue(4)); // Now validate that the interval specified for copying from the receiver // is within the bounds of the receiver (we've already tested startAt) { int length = receiverPointer->bytesSize(); // We can only be in here if stop>=start, so if start>=1, then => stop >= 1 // furthermore if stop <= length then => start <= length int stopAt = startAt+stop-start; if (stopAt > length) return primitiveFailure(4); } // Only works for byte objects ASSERT(receiverPointer->isBytes()); VariantByteObject* receiverBytes = receiverPointer->m_location; #ifdef _DEBUG { Behavior* behavior = receiverPointer->m_oteClass->m_location; ASSERT(!behavior->isIndirect()); } #endif BYTE* pFrom = receiverBytes->m_fields; memmove(pTo+start-1, pFrom+startAt-1, stop-start+1); } // Answers the argument by moving it down over the receiver stackValue(4) = reinterpret_cast<Oop>(argPointer); pop(4); return TRUE; }
// This primitive handles WriteStream>>NextPut:, but only for Arrays, Strings & ByteArrays // Uses but does not modify stack pointer, instead returns the number of bytes to // pop from the Smalltalk stack. BOOL __fastcall Interpreter::primitiveNextPut() { Oop* sp = m_registers.m_stackPointer; WriteStreamOTE* streamPointer = reinterpret_cast<WriteStreamOTE*>(*(sp-1)); // Access receiver under argument //ASSERT(!ObjectMemoryIsIntegerObject(streamPointer) && ObjectMemory::isKindOf(streamPointer, Pointers.ClassPositionableStream)); WriteStream* writeStream = streamPointer->m_location; // Ensure valid stream - checks from Blue Book if (!ObjectMemoryIsIntegerObject(writeStream->m_index) || !ObjectMemoryIsIntegerObject(writeStream->m_writeLimit)) return primitiveFailure(0); // Fails invariant check SMALLINTEGER index = ObjectMemoryIntegerValueOf(writeStream->m_index); SMALLINTEGER limit = ObjectMemoryIntegerValueOf(writeStream->m_writeLimit); // Within the bounds of the limit if (index < 0 || index >= limit) return primitiveFailure(2); Oop value = *(sp); OTE* oteBuf = writeStream->m_array; BehaviorOTE* bufClass = oteBuf->m_oteClass; if (bufClass == Pointers.ClassString) { if (ObjectMemory::fetchClassOf(value) != Pointers.ClassCharacter) return primitiveFailure(4); // Attempt to put non-character StringOTE* oteString = reinterpret_cast<StringOTE*>(oteBuf); if (index >= oteString->bytesSizeForUpdate()) return primitiveFailure(3); // Attempt to put non-character or off end of String String* buf = oteString->m_location; CharOTE* oteChar = reinterpret_cast<CharOTE*>(value); buf->m_characters[index] = static_cast<char>(oteChar->getIndex() - ObjectMemory::FirstCharacterIdx); } else if (bufClass == Pointers.ClassArray) { ArrayOTE* oteArray = reinterpret_cast<ArrayOTE*>(oteBuf); // In bounds of Array? if (index >= oteArray->pointersSizeForUpdate()) return primitiveFailure(3); Array* buf = oteArray->m_location; // We must ref. count value here as we're storing into a heap object slot ObjectMemory::storePointerWithValue(buf->m_elements[index], value); } else if (bufClass == Pointers.ClassByteArray) { if (!ObjectMemoryIsIntegerObject(value)) return primitiveFailure(4); // Attempt to put non-SmallInteger SMALLINTEGER intValue = ObjectMemoryIntegerValueOf(value); if (intValue < 0 || intValue > 255) return primitiveFailure(4); // Can only store 0..255 ByteArrayOTE* oteByteArray = reinterpret_cast<ByteArrayOTE*>(oteBuf); if (index >= oteByteArray->bytesSizeForUpdate()) return primitiveFailure(3); // Attempt to put non-character or off end of String oteByteArray->m_location->m_elements[index] = static_cast<BYTE>(intValue); } else return primitiveFailure(1); writeStream->m_index = Integer::NewSigned32WithRef(index + 1); // Increment the stream index // As we no longer pop stack here, the receiver is still under the argument *(sp-1) = value; return sizeof(Oop); // Pop 4 bytes }
void Process::PostLoadFix(ProcessOTE* oteThis) { // Any overlapped call running when the image was saved is no longer valid, so // we must clear down the "pointer" and remove the back reference if (m_thread != reinterpret_cast<Oop>(Pointers.Nil)) { m_thread = reinterpret_cast<Oop>(Pointers.Nil); oteThis->countDown(); } // Patch any badly created or corrupted processes if (!ObjectMemoryIsIntegerObject(m_fpControl)) { m_fpControl = ObjectMemoryIntegerObjectOf(_DN_SAVE | _RC_NEAR | _PC_64 | _EM_INEXACT | _EM_UNDERFLOW | _EM_OVERFLOW | _EM_DENORMAL); } Oop* pFramePointer = &m_suspendedFrame; Oop framePointer = *pFramePointer; const void* stackBase = m_stack; const void* stackEnd = reinterpret_cast<BYTE*>(this) + oteThis->getSize() - 1; // Wind down the stack adjusting references to self as we go // Start with the suspended context const int delta = m_callbackDepth - 1; while (isIntegerObject(framePointer) && framePointer != ZeroPointer) { framePointer += delta; if (framePointer < Oop(stackBase) || framePointer > Oop(stackEnd)) { trace(L"Warning: Process at %#x has corrupt frame pointer at %#x which will be nilled\n", this, pFramePointer); *pFramePointer = Oop(Pointers.Nil); break; } else *pFramePointer += delta; StackFrame* pFrame = StackFrame::FromFrameOop(*pFramePointer); if (isIntegerObject(pFrame->m_bp)) { pFrame->m_bp += delta; } ASSERT(reinterpret_cast<void*>(pFrame->m_bp) > stackBase && reinterpret_cast<void*>(pFrame->m_bp) < stackEnd); // If a stack only frame, then adjust the BP if (!isIntegerObject(pFrame->m_environment)) { // The frame has an object context, we need to adjust // its back pointer to the frame if it is a MethodContext // The context objects contain no other addresses any more OTE* oteContext = reinterpret_cast<OTE*>(pFrame->m_environment); if (ObjectMemory::isAContext(oteContext)) { Context* ctx = static_cast<Context*>(oteContext->m_location); if (isIntegerObject(ctx->m_frame) && ctx->m_frame != ZeroPointer) { ctx->m_frame += delta; ASSERT(reinterpret_cast<void*>(ctx->m_frame) > stackBase && reinterpret_cast<void*>(ctx->m_frame) < stackEnd); } } } // Adjust the contexts SP if (isIntegerObject(pFrame->m_sp)) { pFrame->m_sp += delta; ASSERT(reinterpret_cast<void*>(pFrame->m_sp) >= stackBase && reinterpret_cast<void*>(pFrame->m_sp) <= stackEnd); } pFramePointer = &pFrame->m_caller; framePointer = *pFramePointer; } framePointer = SuspendedFrame(); if (isIntegerObject(framePointer) && framePointer != ZeroPointer) { // The size of the process should exactly correspond with that required to // hold up to the SP of the suspended frame StackFrame* pFrame = StackFrame::FromFrameOop(framePointer); int size = (pFrame->m_sp - 1) - reinterpret_cast<DWORD>(this) + sizeof(Oop); if (size > 0 && unsigned(size) < oteThis->getSize()) { TRACE(L"WARNING: Resizing process %p from %u to %u\n", oteThis, oteThis->getSize(), size); oteThis->setSize(size); } } // else its dead or not started yet // Later we'll use this slot to count the callback depth m_callbackDepth = ZeroPointer; }
// Signal a specified semaphore after the specified milliseconds duration (the argument). // NOTE: NOT ABSOLUTE VALUE! // If the specified time has already passed, then the TimingSemaphore is signalled immediately. Oop* __fastcall Interpreter::primitiveSignalAtTick(CompiledMethod&, unsigned argumentCount) { Oop tickPointer = stackTop(); SMALLINTEGER nDelay; if (ObjectMemoryIsIntegerObject(tickPointer)) nDelay = ObjectMemoryIntegerValueOf(tickPointer); else { OTE* oteArg = reinterpret_cast<OTE*>(tickPointer); return primitiveFailureWith(PrimitiveFailureNonInteger, oteArg); // ticks must be SmallInteger } // To avoid any race conditions against the global timerID value (it is quite // common for the timer to fire, for example, before the timeSetEvent() call // has actually returned in the duration is very short because the timer thread // is operating at a very high priority), we use an interlocked operation UINT outstandingID = InterlockedExchange(reinterpret_cast<SHAREDLONG*>(&timerID), 0); // If outstanding timer now fires, it will do nothing. We'll end up killing something which is already // dead of course, but that should be OK if (outstandingID) { #ifdef OAD TRACESTREAM << "Killing existing timer with id " << outstandingID << endl; #endif UINT kill = ::timeKillEvent(outstandingID); if (kill != TIMERR_NOERROR) trace("Failed to kill timer %u (%d,%d)!\n\r", outstandingID, kill, GetLastError()); } if (nDelay > 0) { // Temporarily handle old image code that passes timer semaphore as an argument if (argumentCount > 1 && (POTE)Pointers.TimingSemaphore == Pointers.Nil) { ObjectMemory::ProtectConstSpace(PAGE_READWRITE); _Pointers.TimingSemaphore = (SemaphoreOTE*)stackValue(1); ObjectMemory::ProtectConstSpace(PAGE_READONLY); } // Clamp the requested delay to the maximum if it is too large. This simplifies the Delay code in the image a little. if (nDelay > SMALLINTEGER(wTimerMax)) { nDelay = wTimerMax; } // Set the timerID to a non-zero value just in case the timer fires before timeSetEvent() returns. // This allows the TimerProc to recognise the timer as valid (it doesn't really care about the // timerID anyway, just that we're interested in it). // N.B. We shouldn't need an interlocked operation here because, assuming no bugs in the Win32 MM // timers, we've killed any outstanding timer, and the timer thread should be dormant timerID = UINT(-1); // -1 is not used as a timer ID. UINT newTimerID = ::timeSetEvent(nDelay, 0, TimeProc, 0, TIME_ONESHOT); if (newTimerID && newTimerID != UINT(-1)) { // Unless timer has already fired, record the timer id so can cancel if necessary _InterlockedCompareExchange(reinterpret_cast<SHAREDLONG*>(&timerID), newTimerID, -1); pop(argumentCount); // No ref. counting required } else { // System refused to set timer for some reason DWORD error = GetLastError(); trace("Oh no, failed to set a timer for %d mS (%d)!\n\r", nDelay, error); return primitiveFailureWithInt(PrimitiveFailureSystemError, error); } } else if (nDelay == 0) { #ifdef _DEBUG TRACESTREAM << "Requested delay " << dec << nDelay << " passed, signalling immediately" << endl; #endif // The request time has already passed, or does not fall within the // available timer resolution (i.e. it will happen too soon), so signal // it immediately // We must adjust stack before signalling, as may change Process (and therefore stack!) pop(argumentCount); // N.B. Signalling may detect a process switch, but does not actually perform it signalSemaphore(Pointers.TimingSemaphore); } // else requested delay was negative - we allow this to clear down the existing timer #ifdef _DEBUG if (newProcessWaiting()) { ASSERT(m_oteNewProcess->m_oteClass == Pointers.ClassProcess); ProcessOTE* activeProcess = scheduler()->m_activeProcess; TRACESTREAM << "signalAtTick: Caused process switch to " << m_oteNewProcess << endl << "\t\tfrom " << activeProcess << endl << "\tasync signals " << m_qAsyncSignals.isEmpty() << ')' << endl; } #endif // Delay could already have fired CheckProcessSwitch(); return primitiveSuccess(0); }
// This primitive handles PositionableStream>>next, but only for Arrays, Strings and ByteArrays // Unary message, so does not modify stack pointer, and is therefore called directly from the ASM // primitive table without indirection through an ASM thunk. BOOL __fastcall Interpreter::primitiveNext() { PosStreamOTE* streamPointer = reinterpret_cast<PosStreamOTE*>(stackTop()); // Access receiver // Only works for subclasses of PositionableStream (or look alikes) //ASSERT(!ObjectMemoryIsIntegerObject(streamPointer) && ObjectMemory::isKindOf(streamPointer, Pointers.ClassPositionableStream)); PositionableStream* readStream = streamPointer->m_location; // Ensure valid stream - unusually this validity check is included in the Blue Book spec // and appears to be implemented in most Smalltalks, so we implement here too. if (!ObjectMemoryIsIntegerObject(readStream->m_index) || !ObjectMemoryIsIntegerObject(readStream->m_readLimit)) return primitiveFailure(0); // Receiver fails invariant check SMALLINTEGER index = ObjectMemoryIntegerValueOf(readStream->m_index); SMALLINTEGER limit = ObjectMemoryIntegerValueOf(readStream->m_readLimit); // Is the current index within the limits of the collection? // Remember that the index is 1 based (it's a Smalltalk index), and we're 0 based, // so we don't need to increment it until after we've got the next object if (index < 0 || index >= limit) return primitiveFailure(2); // No, fail it OTE* oteBuf = readStream->m_array; BehaviorOTE* bufClass = oteBuf->m_oteClass; if (bufClass == Pointers.ClassString) { StringOTE* oteString = reinterpret_cast<StringOTE*>(oteBuf); // A sanity check - ensure within bounds of object too (again in Blue Book spec) if (MWORD(index) >= oteString->bytesSize()) return primitiveFailure(3); String* buf = oteString->m_location; stackTop() = reinterpret_cast<Oop>(Character::New(buf->m_characters[index])); } // We also support ByteArrays in our primitiveNext (unlike BB). else if (bufClass == Pointers.ClassByteArray) { ByteArrayOTE* oteBytes = reinterpret_cast<ByteArrayOTE*>(oteBuf); if (MWORD(index) >= oteBytes->bytesSize()) return primitiveFailure(3); ByteArray* buf = oteBytes->m_location; stackTop() = ObjectMemoryIntegerObjectOf(buf->m_elements[index]); } else if (bufClass == Pointers.ClassArray) { ArrayOTE* oteArray = reinterpret_cast<ArrayOTE*>(oteBuf); if (MWORD(index) >= oteArray->pointersSize()) return primitiveFailure(3); Array* buf = oteArray->m_location; stackTop() = buf->m_elements[index]; } else return primitiveFailure(1); // Collection cannot be handled by primitive, rely on Smalltalk code // When incrementing the index we must allow for it overflowing a SmallInteger, even though // this is extremely unlikely in practice readStream->m_index = Integer::NewSigned32WithRef(index+1); return primitiveSuccess(); // Succeed }
// Non-standard, but has very beneficial effect on performance BOOL __fastcall Interpreter::primitiveNextPutAll() { Oop* sp = m_registers.m_stackPointer; WriteStreamOTE* streamPointer = reinterpret_cast<WriteStreamOTE*>(*(sp-1)); // Access receiver under argument WriteStream* writeStream = streamPointer->m_location; // Ensure valid stream - checks from Blue Book if (!ObjectMemoryIsIntegerObject(writeStream->m_index) || !ObjectMemoryIsIntegerObject(writeStream->m_writeLimit)) return primitiveFailure(0); // Fails invariant check SMALLINTEGER index = ObjectMemoryIntegerValueOf(writeStream->m_index); SMALLINTEGER limit = ObjectMemoryIntegerValueOf(writeStream->m_writeLimit); if (index < 0) return primitiveFailure(2); Oop value = *(sp); OTE* oteBuf = writeStream->m_array; BehaviorOTE* bufClass = oteBuf->m_oteClass; MWORD newIndex; if (bufClass == Pointers.ClassString) { BehaviorOTE* oteClass = ObjectMemory::fetchClassOf(value); if (oteClass != Pointers.ClassString && oteClass != Pointers.ClassSymbol) return primitiveFailure(4); // Attempt to put non-string StringOTE* oteString = reinterpret_cast<StringOTE*>(value); String* str = oteString->m_location; MWORD valueSize = oteString->bytesSize(); newIndex = MWORD(index)+valueSize; if (newIndex >= static_cast<MWORD>(limit)) // Beyond write limit return primitiveFailure(2); if (static_cast<int>(newIndex) >= oteBuf->bytesSizeForUpdate()) return primitiveFailure(3); // Attempt to write off end of buffer String* buf = static_cast<String*>(oteBuf->m_location); memcpy(buf->m_characters+index, str->m_characters, valueSize); } else if (bufClass == Pointers.ClassByteArray) { if (ObjectMemory::fetchClassOf(value) != bufClass) return primitiveFailure(4); // Attempt to put non-ByteArray ByteArrayOTE* oteBytes = reinterpret_cast<ByteArrayOTE*>(value); ByteArray* bytes = oteBytes->m_location; MWORD valueSize = oteBytes->bytesSize(); newIndex = MWORD(index)+valueSize; if (newIndex >= (MWORD)limit) // Beyond write limit return primitiveFailure(2); if (static_cast<int>(newIndex) >= oteBuf->bytesSizeForUpdate()) return primitiveFailure(3); // Attempt to write off end of buffer ByteArray* buf = static_cast<ByteArray*>(oteBuf->m_location); memcpy(buf->m_elements+index, bytes->m_elements, valueSize); } else if (bufClass == Pointers.ClassArray) { if (ObjectMemory::fetchClassOf(value) != Pointers.ClassArray) return primitiveFailure(4); // Attempt to put non-Array ArrayOTE* oteArray = reinterpret_cast<ArrayOTE*>(value); Array* array = oteArray->m_location; MWORD valueSize = oteArray->pointersSize(); newIndex = MWORD(index) + valueSize; if (newIndex >= (MWORD)limit) // Beyond write limit return primitiveFailure(2); if (static_cast<int>(newIndex) >= oteBuf->pointersSizeForUpdate()) return primitiveFailure(3); // Attempt to write off end of buffer Array* buf = static_cast<Array*>(oteBuf->m_location); for (MWORD i = 0; i < valueSize; i++) { ObjectMemory::storePointerWithValue(buf->m_elements[index + i], array->m_elements[i]); } } else return primitiveFailure(1); writeStream->m_index = Integer::NewUnsigned32WithRef(newIndex); // Increment the stream index // As we no longer pop stack here, the receiver is still under the argument *(sp-1) = value; return sizeof(Oop); // Pop 4 bytes }
// This is a double dispatched primitive which knows that the argument is a byte object (though // we still check this to avoid GPFs), and the receiver is guaranteed to be an address object. e.g. // // anExternalAddress replaceBytesOf: anOtherByteObject from: start to: stop startingAt: startAt // BOOL __fastcall Interpreter::primitiveIndirectReplaceBytes() { Oop integerPointer = stackTop(); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(0); // startAt is not an integer SMALLINTEGER startAt = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(1); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(1); // stop is not an integer SMALLINTEGER stop = ObjectMemoryIntegerValueOf(integerPointer); integerPointer = stackValue(2); if (!ObjectMemoryIsIntegerObject(integerPointer)) return primitiveFailure(2); // start is not an integer SMALLINTEGER start = ObjectMemoryIntegerValueOf(integerPointer); OTE* argPointer = reinterpret_cast<OTE*>(stackValue(3)); if (ObjectMemoryIsIntegerObject(argPointer) || !argPointer->isBytes()) return primitiveFailure(3); // Argument MUST be a byte object // Empty move if stop before start, is considered valid regardless (strange but true) if (stop >= start) { if (start < 1 || startAt < 1) return primitiveFailure(4); // out-of-bounds AddressOTE* receiverPointer = reinterpret_cast<AddressOTE*>(stackValue(4)); // Only works for byte objects ASSERT(receiverPointer->isBytes()); ExternalAddress* receiverBytes = receiverPointer->m_location; #ifdef _DEBUG { Behavior* behavior = receiverPointer->m_oteClass->m_location; ASSERT(behavior->isIndirect()); } #endif // Because the receiver is an address, we do not know the size of the object // it points at, and so cannot perform any bounds checks - BEWARE BYTE* pFrom = static_cast<BYTE*>(receiverBytes->m_pointer); // We still permit the argument to be an address to cut down on the double dispatching // required. BYTE* pTo; Behavior* behavior = argPointer->m_oteClass->m_location; if (behavior->isIndirect()) { AddressOTE* oteBytes = reinterpret_cast<AddressOTE*>(argPointer); // Cannot check length pTo = static_cast<BYTE*>(oteBytes->m_location->m_pointer); } else { // Can check that not writing off the end of the argument int length = argPointer->bytesSize(); // We can only be in here if stop>=start, so => stop-start >= 0 // therefore if startAt >= 1 then => stopAt >= 1, for similar // reasons (since stopAt >= startAt) we don't need to test // that startAt <= length if (stop > length) return primitiveFailure(4); // Bounds error VariantByteObject* argBytes = reinterpret_cast<BytesOTE*>(argPointer)->m_location; pTo = argBytes->m_fields; } memmove(pTo+start-1, pFrom+startAt-1, stop-start+1); } // Answers the argument by moving it down over the receiver stackValue(4) = reinterpret_cast<Oop>(argPointer); pop(4); return TRUE; }