| // Copyright (c) 2011, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| #include "vm/exceptions.h" |
| |
| #include "platform/address_sanitizer.h" |
| |
| #include "lib/stacktrace.h" |
| |
| #include "vm/dart_api_impl.h" |
| #include "vm/dart_entry.h" |
| #include "vm/datastream.h" |
| #include "vm/debugger.h" |
| #include "vm/deopt_instructions.h" |
| #include "vm/flags.h" |
| #include "vm/log.h" |
| #include "vm/longjump.h" |
| #include "vm/object.h" |
| #include "vm/object_store.h" |
| #include "vm/stack_frame.h" |
| #include "vm/stub_code.h" |
| #include "vm/symbols.h" |
| #include "vm/tags.h" |
| |
| namespace dart { |
| |
| DECLARE_FLAG(bool, enable_interpreter); |
| DECLARE_FLAG(bool, trace_deoptimization); |
| DEFINE_FLAG(bool, |
| print_stacktrace_at_throw, |
| false, |
| "Prints a stack trace everytime a throw occurs."); |
| |
| class StackTraceBuilder : public ValueObject { |
| public: |
| StackTraceBuilder() {} |
| virtual ~StackTraceBuilder() {} |
| |
| virtual void AddFrame(const Object& code, const Smi& offset) = 0; |
| }; |
| |
| class RegularStackTraceBuilder : public StackTraceBuilder { |
| public: |
| explicit RegularStackTraceBuilder(Zone* zone) |
| : code_list_( |
| GrowableObjectArray::Handle(zone, GrowableObjectArray::New())), |
| pc_offset_list_( |
| GrowableObjectArray::Handle(zone, GrowableObjectArray::New())) {} |
| ~RegularStackTraceBuilder() {} |
| |
| const GrowableObjectArray& code_list() const { return code_list_; } |
| const GrowableObjectArray& pc_offset_list() const { return pc_offset_list_; } |
| |
| virtual void AddFrame(const Object& code, const Smi& offset) { |
| code_list_.Add(code); |
| pc_offset_list_.Add(offset); |
| } |
| |
| private: |
| const GrowableObjectArray& code_list_; |
| const GrowableObjectArray& pc_offset_list_; |
| |
| DISALLOW_COPY_AND_ASSIGN(RegularStackTraceBuilder); |
| }; |
| |
| class PreallocatedStackTraceBuilder : public StackTraceBuilder { |
| public: |
| explicit PreallocatedStackTraceBuilder(const Instance& stacktrace) |
| : stacktrace_(StackTrace::Cast(stacktrace)), |
| cur_index_(0), |
| dropped_frames_(0) { |
| ASSERT(stacktrace_.raw() == |
| Isolate::Current()->object_store()->preallocated_stack_trace()); |
| } |
| ~PreallocatedStackTraceBuilder() {} |
| |
| virtual void AddFrame(const Object& code, const Smi& offset); |
| |
| private: |
| static const int kNumTopframes = StackTrace::kPreallocatedStackdepth / 2; |
| |
| const StackTrace& stacktrace_; |
| intptr_t cur_index_; |
| intptr_t dropped_frames_; |
| |
| DISALLOW_COPY_AND_ASSIGN(PreallocatedStackTraceBuilder); |
| }; |
| |
| void PreallocatedStackTraceBuilder::AddFrame(const Object& code, |
| const Smi& offset) { |
| if (cur_index_ >= StackTrace::kPreallocatedStackdepth) { |
| // The number of frames is overflowing the preallocated stack trace object. |
| Object& frame_code = Object::Handle(); |
| Smi& frame_offset = Smi::Handle(); |
| intptr_t start = StackTrace::kPreallocatedStackdepth - (kNumTopframes - 1); |
| intptr_t null_slot = start - 2; |
| // We are going to drop one frame. |
| dropped_frames_++; |
| // Add an empty slot to indicate the overflow so that the toString |
| // method can account for the overflow. |
| if (stacktrace_.CodeAtFrame(null_slot) != Code::null()) { |
| stacktrace_.SetCodeAtFrame(null_slot, frame_code); |
| // We drop an extra frame here too. |
| dropped_frames_++; |
| } |
| // Encode the number of dropped frames into the pc offset. |
| frame_offset ^= Smi::New(dropped_frames_); |
| stacktrace_.SetPcOffsetAtFrame(null_slot, frame_offset); |
| // Move frames one slot down so that we can accommodate the new frame. |
| for (intptr_t i = start; i < StackTrace::kPreallocatedStackdepth; i++) { |
| intptr_t prev = (i - 1); |
| frame_code = stacktrace_.CodeAtFrame(i); |
| frame_offset = stacktrace_.PcOffsetAtFrame(i); |
| stacktrace_.SetCodeAtFrame(prev, frame_code); |
| stacktrace_.SetPcOffsetAtFrame(prev, frame_offset); |
| } |
| cur_index_ = (StackTrace::kPreallocatedStackdepth - 1); |
| } |
| stacktrace_.SetCodeAtFrame(cur_index_, code); |
| stacktrace_.SetPcOffsetAtFrame(cur_index_, offset); |
| cur_index_ += 1; |
| } |
| |
| static void BuildStackTrace(StackTraceBuilder* builder) { |
| StackFrameIterator frames(ValidationPolicy::kDontValidateFrames, |
| Thread::Current(), |
| StackFrameIterator::kNoCrossThreadIteration); |
| StackFrame* frame = frames.NextFrame(); |
| ASSERT(frame != NULL); // We expect to find a dart invocation frame. |
| Code& code = Code::Handle(); |
| Bytecode& bytecode = Bytecode::Handle(); |
| Smi& offset = Smi::Handle(); |
| while (frame != NULL) { |
| if (frame->IsDartFrame()) { |
| if (frame->is_interpreted()) { |
| bytecode = frame->LookupDartBytecode(); |
| ASSERT(bytecode.ContainsInstructionAt(frame->pc())); |
| offset = Smi::New(frame->pc() - bytecode.PayloadStart()); |
| builder->AddFrame(bytecode, offset); |
| } else { |
| code = frame->LookupDartCode(); |
| ASSERT(code.ContainsInstructionAt(frame->pc())); |
| offset = Smi::New(frame->pc() - code.PayloadStart()); |
| builder->AddFrame(code, offset); |
| } |
| } |
| frame = frames.NextFrame(); |
| } |
| } |
| |
| class ExceptionHandlerFinder : public StackResource { |
| public: |
| explicit ExceptionHandlerFinder(Thread* thread) |
| : StackResource(thread), thread_(thread) {} |
| |
| // Iterate through the stack frames and try to find a frame with an |
| // exception handler. Once found, set the pc, sp and fp so that execution |
| // can continue in that frame. Sets 'needs_stacktrace' if there is no |
| // cath-all handler or if a stack-trace is specified in the catch. |
| bool Find() { |
| StackFrameIterator frames(ValidationPolicy::kDontValidateFrames, |
| Thread::Current(), |
| StackFrameIterator::kNoCrossThreadIteration); |
| StackFrame* frame = frames.NextFrame(); |
| if (frame == NULL) return false; // No Dart frame. |
| handler_pc_set_ = false; |
| needs_stacktrace = false; |
| bool is_catch_all = false; |
| uword temp_handler_pc = kUwordMax; |
| bool is_optimized = false; |
| code_ = NULL; |
| catch_entry_moves_cache_ = thread_->isolate()->catch_entry_moves_cache(); |
| |
| while (!frame->IsEntryFrame()) { |
| if (frame->IsDartFrame()) { |
| if (frame->FindExceptionHandler(thread_, &temp_handler_pc, |
| &needs_stacktrace, &is_catch_all, |
| &is_optimized)) { |
| if (!handler_pc_set_) { |
| handler_pc_set_ = true; |
| handler_pc = temp_handler_pc; |
| handler_sp = frame->sp(); |
| handler_fp = frame->fp(); |
| if (is_optimized) { |
| pc_ = frame->pc(); |
| code_ = &Code::Handle(frame->LookupDartCode()); |
| CatchEntryMovesRefPtr* cached_catch_entry_moves = |
| catch_entry_moves_cache_->Lookup(pc_); |
| if (cached_catch_entry_moves != NULL) { |
| cached_catch_entry_moves_ = *cached_catch_entry_moves; |
| } |
| #if !defined(DART_PRECOMPILED_RUNTIME) && !defined(DART_PRECOMPILER) |
| intptr_t num_vars = Smi::Value(code_->variables()); |
| if (cached_catch_entry_moves_.IsEmpty()) { |
| GetCatchEntryMovesFromDeopt(num_vars, frame); |
| } |
| #else |
| if (cached_catch_entry_moves_.IsEmpty()) { |
| ReadCompressedCatchEntryMoves(); |
| } |
| #endif // !defined(DART_PRECOMPILED_RUNTIME) && !defined(DART_PRECOMPILER) |
| } |
| } |
| if (needs_stacktrace || is_catch_all) { |
| return true; |
| } |
| } |
| } // if frame->IsDartFrame |
| frame = frames.NextFrame(); |
| ASSERT(frame != NULL); |
| } // while !frame->IsEntryFrame |
| ASSERT(frame->IsEntryFrame()); |
| if (!handler_pc_set_) { |
| handler_pc = frame->pc(); |
| handler_sp = frame->sp(); |
| handler_fp = frame->fp(); |
| } |
| // No catch-all encountered, needs stacktrace. |
| needs_stacktrace = true; |
| return handler_pc_set_; |
| } |
| |
| // When entering catch block in the optimized code we need to execute |
| // catch entry moves that would morph the state of the frame into |
| // what catch entry expects. |
| void PrepareFrameForCatchEntry() { |
| if (code_ == nullptr || !code_->is_optimized()) { |
| return; |
| } |
| |
| if (cached_catch_entry_moves_.IsEmpty()) { |
| catch_entry_moves_cache_->Insert( |
| pc_, CatchEntryMovesRefPtr(catch_entry_moves_)); |
| } else { |
| catch_entry_moves_ = &cached_catch_entry_moves_.moves(); |
| } |
| |
| ExecuteCatchEntryMoves(*catch_entry_moves_); |
| } |
| |
| void ExecuteCatchEntryMoves(const CatchEntryMoves& moves) { |
| uword fp = handler_fp; |
| ObjectPool* pool = nullptr; |
| for (int j = 0; j < moves.count(); j++) { |
| const CatchEntryMove& move = moves.At(j); |
| |
| RawObject* value; |
| switch (move.source_kind()) { |
| case CatchEntryMove::SourceKind::kConstant: |
| if (pool == nullptr) { |
| pool = &ObjectPool::Handle(code_->object_pool()); |
| } |
| value = pool->ObjectAt(move.src_slot()); |
| break; |
| |
| case CatchEntryMove::SourceKind::kTaggedSlot: |
| value = *TaggedSlotAt(fp, move.src_slot()); |
| break; |
| |
| case CatchEntryMove::SourceKind::kDoubleSlot: |
| value = Double::New(*SlotAt<double>(fp, move.src_slot())); |
| break; |
| |
| case CatchEntryMove::SourceKind::kFloat32x4Slot: |
| value = Float32x4::New(*SlotAt<simd128_value_t>(fp, move.src_slot())); |
| break; |
| |
| case CatchEntryMove::SourceKind::kFloat64x2Slot: |
| value = Float64x2::New(*SlotAt<simd128_value_t>(fp, move.src_slot())); |
| break; |
| |
| case CatchEntryMove::SourceKind::kInt32x4Slot: |
| value = Int32x4::New(*SlotAt<simd128_value_t>(fp, move.src_slot())); |
| break; |
| |
| case CatchEntryMove::SourceKind::kInt64PairSlot: |
| value = Integer::New( |
| Utils::LowHighTo64Bits(*SlotAt<uint32_t>(fp, move.src_lo_slot()), |
| *SlotAt<int32_t>(fp, move.src_hi_slot()))); |
| break; |
| |
| case CatchEntryMove::SourceKind::kInt64Slot: |
| value = Integer::New(*SlotAt<int64_t>(fp, move.src_slot())); |
| break; |
| |
| case CatchEntryMove::SourceKind::kInt32Slot: |
| value = Integer::New(*SlotAt<int32_t>(fp, move.src_slot())); |
| break; |
| |
| case CatchEntryMove::SourceKind::kUint32Slot: |
| value = Integer::New(*SlotAt<uint32_t>(fp, move.src_slot())); |
| break; |
| |
| default: |
| UNREACHABLE(); |
| } |
| |
| *TaggedSlotAt(fp, move.dest_slot()) = value; |
| } |
| } |
| |
| #if defined(DART_PRECOMPILED_RUNTIME) || defined(DART_PRECOMPILER) |
| void ReadCompressedCatchEntryMoves() { |
| intptr_t pc_offset = pc_ - code_->PayloadStart(); |
| const TypedData& td = TypedData::Handle(code_->catch_entry_moves_maps()); |
| NoSafepointScope no_safepoint; |
| ReadStream stream(static_cast<uint8_t*>(td.DataAddr(0)), td.Length()); |
| |
| intptr_t prefix_length = 0, suffix_length = 0, suffix_offset = 0; |
| while (stream.PendingBytes() > 0) { |
| intptr_t target_pc_offset = Reader::Read(&stream); |
| prefix_length = Reader::Read(&stream); |
| suffix_length = Reader::Read(&stream); |
| suffix_offset = Reader::Read(&stream); |
| if (pc_offset == target_pc_offset) { |
| break; |
| } |
| |
| // Skip the moves. |
| for (intptr_t j = 0; j < prefix_length; j++) { |
| CatchEntryMove::ReadFrom(&stream); |
| } |
| } |
| ASSERT((stream.PendingBytes() > 0) || (prefix_length == 0)); |
| |
| CatchEntryMoves* moves = |
| CatchEntryMoves::Allocate(prefix_length + suffix_length); |
| for (int j = 0; j < prefix_length; j++) { |
| moves->At(j) = CatchEntryMove::ReadFrom(&stream); |
| } |
| ReadCompressedCatchEntryMovesSuffix(&stream, suffix_offset, suffix_length, |
| moves, prefix_length); |
| catch_entry_moves_ = moves; |
| } |
| |
| void ReadCompressedCatchEntryMovesSuffix(ReadStream* stream, |
| intptr_t offset, |
| intptr_t length, |
| CatchEntryMoves* moves, |
| intptr_t moves_offset) { |
| stream->SetPosition(offset); |
| Reader::Read(stream); // skip pc_offset |
| Reader::Read(stream); // skip variables |
| intptr_t suffix_length = Reader::Read(stream); |
| intptr_t suffix_offset = Reader::Read(stream); |
| intptr_t to_read = length - suffix_length; |
| for (int j = 0; j < to_read; j++) { |
| moves->At(moves_offset + j) = CatchEntryMove::ReadFrom(stream); |
| } |
| if (suffix_length > 0) { |
| ReadCompressedCatchEntryMovesSuffix(stream, suffix_offset, suffix_length, |
| moves, moves_offset + to_read); |
| } |
| } |
| |
| #else |
| void GetCatchEntryMovesFromDeopt(intptr_t num_vars, StackFrame* frame) { |
| Isolate* isolate = thread_->isolate(); |
| DeoptContext* deopt_context = |
| new DeoptContext(frame, *code_, DeoptContext::kDestIsAllocated, NULL, |
| NULL, true, false /* deoptimizing_code */); |
| isolate->set_deopt_context(deopt_context); |
| |
| catch_entry_moves_ = deopt_context->ToCatchEntryMoves(num_vars); |
| |
| isolate->set_deopt_context(NULL); |
| delete deopt_context; |
| } |
| #endif // defined(DART_PRECOMPILED_RUNTIME) || defined(DART_PRECOMPILER) |
| |
| bool needs_stacktrace; |
| uword handler_pc; |
| uword handler_sp; |
| uword handler_fp; |
| |
| private: |
| template <typename T> |
| static T* SlotAt(uword fp, int stack_slot) { |
| #if defined(TARGET_ARCH_DBC) |
| return reinterpret_cast<T*>(fp + stack_slot * kWordSize); |
| #else |
| const intptr_t frame_slot = |
| runtime_frame_layout.FrameSlotForVariableIndex(-stack_slot); |
| return reinterpret_cast<T*>(fp + frame_slot * kWordSize); |
| #endif |
| } |
| |
| static RawObject** TaggedSlotAt(uword fp, int stack_slot) { |
| return SlotAt<RawObject*>(fp, stack_slot); |
| } |
| |
| typedef ReadStream::Raw<sizeof(intptr_t), intptr_t> Reader; |
| Thread* thread_; |
| Code* code_; |
| bool handler_pc_set_; |
| intptr_t pc_; // Current pc in the handler frame. |
| |
| const CatchEntryMoves* catch_entry_moves_ = nullptr; |
| CatchEntryMovesCache* catch_entry_moves_cache_ = nullptr; |
| CatchEntryMovesRefPtr cached_catch_entry_moves_; |
| }; |
| |
| CatchEntryMove CatchEntryMove::ReadFrom(ReadStream* stream) { |
| using Reader = ReadStream::Raw<sizeof(intptr_t), intptr_t>; |
| const intptr_t src = Reader::Read(stream); |
| const intptr_t dest_and_kind = Reader::Read(stream); |
| return CatchEntryMove(src, dest_and_kind); |
| } |
| |
| #if !defined(DART_PRECOMPILED_RUNTIME) |
| void CatchEntryMove::WriteTo(WriteStream* stream) { |
| using Writer = WriteStream::Raw<sizeof(intptr_t), intptr_t>; |
| Writer::Write(stream, src_); |
| Writer::Write(stream, dest_and_kind_); |
| } |
| #endif |
| |
| static void FindErrorHandler(uword* handler_pc, |
| uword* handler_sp, |
| uword* handler_fp) { |
| StackFrameIterator frames(ValidationPolicy::kDontValidateFrames, |
| Thread::Current(), |
| StackFrameIterator::kNoCrossThreadIteration); |
| StackFrame* frame = frames.NextFrame(); |
| ASSERT(frame != NULL); |
| while (!frame->IsEntryFrame()) { |
| frame = frames.NextFrame(); |
| ASSERT(frame != NULL); |
| } |
| ASSERT(frame->IsEntryFrame()); |
| *handler_pc = frame->pc(); |
| *handler_sp = frame->sp(); |
| *handler_fp = frame->fp(); |
| } |
| |
| static uword RemapExceptionPCForDeopt(Thread* thread, |
| uword program_counter, |
| uword frame_pointer) { |
| #if !defined(TARGET_ARCH_DBC) |
| MallocGrowableArray<PendingLazyDeopt>* pending_deopts = |
| thread->isolate()->pending_deopts(); |
| if (pending_deopts->length() > 0) { |
| // Check if the target frame is scheduled for lazy deopt. |
| for (intptr_t i = 0; i < pending_deopts->length(); i++) { |
| if ((*pending_deopts)[i].fp() == frame_pointer) { |
| // Deopt should now resume in the catch handler instead of after the |
| // call. |
| (*pending_deopts)[i].set_pc(program_counter); |
| |
| // Jump to the deopt stub instead of the catch handler. |
| program_counter = StubCode::DeoptimizeLazyFromThrow().EntryPoint(); |
| if (FLAG_trace_deoptimization) { |
| THR_Print("Throwing to frame scheduled for lazy deopt fp=%" Pp "\n", |
| frame_pointer); |
| } |
| break; |
| } |
| } |
| } |
| #endif // !DBC |
| return program_counter; |
| } |
| |
| static void ClearLazyDeopts(Thread* thread, uword frame_pointer) { |
| #if !defined(TARGET_ARCH_DBC) |
| MallocGrowableArray<PendingLazyDeopt>* pending_deopts = |
| thread->isolate()->pending_deopts(); |
| if (pending_deopts->length() > 0) { |
| // We may be jumping over frames scheduled for lazy deopt. Remove these |
| // frames from the pending deopt table, but only after unmarking them so |
| // any stack walk that happens before the stack is unwound will still work. |
| { |
| DartFrameIterator frames(thread, |
| StackFrameIterator::kNoCrossThreadIteration); |
| StackFrame* frame = frames.NextFrame(); |
| while ((frame != NULL) && (frame->fp() < frame_pointer)) { |
| if (frame->IsMarkedForLazyDeopt()) { |
| frame->UnmarkForLazyDeopt(); |
| } |
| frame = frames.NextFrame(); |
| } |
| } |
| |
| #if defined(DEBUG) |
| ValidateFrames(); |
| #endif |
| |
| for (intptr_t i = 0; i < pending_deopts->length(); i++) { |
| if ((*pending_deopts)[i].fp() < frame_pointer) { |
| if (FLAG_trace_deoptimization) { |
| THR_Print( |
| "Lazy deopt skipped due to throw for " |
| "fp=%" Pp ", pc=%" Pp "\n", |
| (*pending_deopts)[i].fp(), (*pending_deopts)[i].pc()); |
| } |
| pending_deopts->RemoveAt(i); |
| } |
| } |
| |
| #if defined(DEBUG) |
| ValidateFrames(); |
| #endif |
| } |
| #endif // !DBC |
| } |
| |
| static void JumpToExceptionHandler(Thread* thread, |
| uword program_counter, |
| uword stack_pointer, |
| uword frame_pointer, |
| const Object& exception_object, |
| const Object& stacktrace_object) { |
| uword remapped_pc = |
| RemapExceptionPCForDeopt(thread, program_counter, frame_pointer); |
| thread->set_active_exception(exception_object); |
| thread->set_active_stacktrace(stacktrace_object); |
| thread->set_resume_pc(remapped_pc); |
| uword run_exception_pc = StubCode::RunExceptionHandler().EntryPoint(); |
| Exceptions::JumpToFrame(thread, run_exception_pc, stack_pointer, |
| frame_pointer, false /* do not clear deopt */); |
| } |
| |
| NO_SANITIZE_SAFE_STACK // This function manipulates the safestack pointer. |
| void Exceptions::JumpToFrame(Thread* thread, |
| uword program_counter, |
| uword stack_pointer, |
| uword frame_pointer, |
| bool clear_deopt_at_target) { |
| uword fp_for_clearing = |
| (clear_deopt_at_target ? frame_pointer + 1 : frame_pointer); |
| ClearLazyDeopts(thread, fp_for_clearing); |
| #if defined(USING_SIMULATOR) |
| // Unwinding of the C++ frames and destroying of their stack resources is done |
| // by the simulator, because the target stack_pointer is a simulated stack |
| // pointer and not the C++ stack pointer. |
| |
| // Continue simulating at the given pc in the given frame after setting up the |
| // exception object in the kExceptionObjectReg register and the stacktrace |
| // object (may be raw null) in the kStackTraceObjectReg register. |
| |
| Simulator::Current()->JumpToFrame(program_counter, stack_pointer, |
| frame_pointer, thread); |
| #else |
| |
| #if !defined(DART_PRECOMPILED_RUNTIME) |
| // TODO(regis): We still possibly need to unwind interpreter frames if they |
| // are callee frames of the C++ frame handling the exception. |
| if (FLAG_enable_interpreter) { |
| Interpreter* interpreter = thread->interpreter(); |
| if ((interpreter != NULL) && interpreter->HasFrame(frame_pointer)) { |
| interpreter->JumpToFrame(program_counter, stack_pointer, frame_pointer, |
| thread); |
| } |
| } |
| #endif // !defined(DART_PRECOMPILED_RUNTIME) |
| |
| // Prepare for unwinding frames by destroying all the stack resources |
| // in the previous frames. |
| StackResource::Unwind(thread); |
| |
| // Call a stub to set up the exception object in kExceptionObjectReg, |
| // to set up the stacktrace object in kStackTraceObjectReg, and to |
| // continue execution at the given pc in the given frame. |
| typedef void (*ExcpHandler)(uword, uword, uword, Thread*); |
| ExcpHandler func = |
| reinterpret_cast<ExcpHandler>(StubCode::JumpToFrame().EntryPoint()); |
| |
| // Unpoison the stack before we tear it down in the generated stub code. |
| uword current_sp = OSThread::GetCurrentStackPointer() - 1024; |
| ASAN_UNPOISON(reinterpret_cast<void*>(current_sp), |
| stack_pointer - current_sp); |
| |
| // We are jumping over C++ frames, so we have to set the safestack pointer |
| // back to what it was when we entered the runtime from Dart code. |
| #if defined(USING_SAFE_STACK) |
| const uword saved_ssp = thread->saved_safestack_limit(); |
| OSThread::SetCurrentSafestackPointer(saved_ssp); |
| #endif |
| |
| func(program_counter, stack_pointer, frame_pointer, thread); |
| #endif |
| UNREACHABLE(); |
| } |
| |
| static RawField* LookupStackTraceField(const Instance& instance) { |
| if (instance.GetClassId() < kNumPredefinedCids) { |
| // 'class Error' is not a predefined class. |
| return Field::null(); |
| } |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| Isolate* isolate = thread->isolate(); |
| Class& error_class = |
| Class::Handle(zone, isolate->object_store()->error_class()); |
| if (error_class.IsNull()) { |
| const Library& core_lib = Library::Handle(zone, Library::CoreLibrary()); |
| error_class = core_lib.LookupClass(Symbols::Error()); |
| ASSERT(!error_class.IsNull()); |
| isolate->object_store()->set_error_class(error_class); |
| } |
| // If instance class extends 'class Error' return '_stackTrace' field. |
| Class& test_class = Class::Handle(zone, instance.clazz()); |
| AbstractType& type = AbstractType::Handle(zone, AbstractType::null()); |
| while (true) { |
| if (test_class.raw() == error_class.raw()) { |
| return error_class.LookupInstanceFieldAllowPrivate( |
| Symbols::_stackTrace()); |
| } |
| type = test_class.super_type(); |
| if (type.IsNull()) return Field::null(); |
| test_class = type.type_class(); |
| } |
| UNREACHABLE(); |
| return Field::null(); |
| } |
| |
| RawStackTrace* Exceptions::CurrentStackTrace() { |
| return GetStackTraceForException(); |
| } |
| |
| static void ThrowExceptionHelper(Thread* thread, |
| const Instance& incoming_exception, |
| const Instance& existing_stacktrace, |
| const bool is_rethrow) { |
| Zone* zone = thread->zone(); |
| Isolate* isolate = thread->isolate(); |
| bool use_preallocated_stacktrace = false; |
| Instance& exception = Instance::Handle(zone, incoming_exception.raw()); |
| if (exception.IsNull()) { |
| exception ^= |
| Exceptions::Create(Exceptions::kNullThrown, Object::empty_array()); |
| } else if (exception.raw() == isolate->object_store()->out_of_memory() || |
| exception.raw() == isolate->object_store()->stack_overflow()) { |
| use_preallocated_stacktrace = true; |
| } |
| // Find the exception handler and determine if the handler needs a |
| // stacktrace. |
| ExceptionHandlerFinder finder(thread); |
| bool handler_exists = finder.Find(); |
| uword handler_pc = finder.handler_pc; |
| uword handler_sp = finder.handler_sp; |
| uword handler_fp = finder.handler_fp; |
| bool handler_needs_stacktrace = finder.needs_stacktrace; |
| Instance& stacktrace = Instance::Handle(zone); |
| if (use_preallocated_stacktrace) { |
| if (handler_pc == 0) { |
| // No Dart frame. |
| ASSERT(incoming_exception.raw() == |
| isolate->object_store()->out_of_memory()); |
| const UnhandledException& error = UnhandledException::Handle( |
| zone, isolate->object_store()->preallocated_unhandled_exception()); |
| thread->long_jump_base()->Jump(1, error); |
| UNREACHABLE(); |
| } |
| stacktrace ^= isolate->object_store()->preallocated_stack_trace(); |
| PreallocatedStackTraceBuilder frame_builder(stacktrace); |
| ASSERT(existing_stacktrace.IsNull() || |
| (existing_stacktrace.raw() == stacktrace.raw())); |
| ASSERT(existing_stacktrace.IsNull() || is_rethrow); |
| if (handler_needs_stacktrace && existing_stacktrace.IsNull()) { |
| BuildStackTrace(&frame_builder); |
| } |
| } else { |
| if (!existing_stacktrace.IsNull()) { |
| // If we have an existing stack trace then this better be a rethrow. The |
| // reverse is not necessarily true (e.g. Dart_PropagateError can cause |
| // a rethrow being called without an existing stacktrace.) |
| ASSERT(is_rethrow); |
| stacktrace = existing_stacktrace.raw(); |
| } else { |
| // Get stacktrace field of class Error to determine whether we have a |
| // subclass of Error which carries around its stack trace. |
| const Field& stacktrace_field = |
| Field::Handle(zone, LookupStackTraceField(exception)); |
| if (!stacktrace_field.IsNull() || handler_needs_stacktrace) { |
| // Collect the stacktrace if needed. |
| ASSERT(existing_stacktrace.IsNull()); |
| stacktrace = Exceptions::CurrentStackTrace(); |
| // If we have an Error object, then set its stackTrace field only if it |
| // not yet initialized. |
| if (!stacktrace_field.IsNull() && |
| (exception.GetField(stacktrace_field) == Object::null())) { |
| exception.SetField(stacktrace_field, stacktrace); |
| } |
| } |
| } |
| } |
| // We expect to find a handler_pc, if the exception is unhandled |
| // then we expect to at least have the dart entry frame on the |
| // stack as Exceptions::Throw should happen only after a dart |
| // invocation has been done. |
| ASSERT(handler_pc != 0); |
| |
| if (FLAG_print_stacktrace_at_throw) { |
| THR_Print("Exception '%s' thrown:\n", exception.ToCString()); |
| THR_Print("%s\n", stacktrace.ToCString()); |
| } |
| if (handler_exists) { |
| finder.PrepareFrameForCatchEntry(); |
| // Found a dart handler for the exception, jump to it. |
| JumpToExceptionHandler(thread, handler_pc, handler_sp, handler_fp, |
| exception, stacktrace); |
| } else { |
| // No dart exception handler found in this invocation sequence, |
| // so we create an unhandled exception object and return to the |
| // invocation stub so that it returns this unhandled exception |
| // object. The C++ code which invoked this dart sequence can check |
| // and do the appropriate thing (rethrow the exception to the |
| // dart invocation sequence above it, print diagnostics and terminate |
| // the isolate etc.). This can happen in the compiler, which is not |
| // allowed to allocate in new space, so we pass the kOld argument. |
| const UnhandledException& unhandled_exception = UnhandledException::Handle( |
| zone, UnhandledException::New(exception, stacktrace, Heap::kOld)); |
| stacktrace = StackTrace::null(); |
| JumpToExceptionHandler(thread, handler_pc, handler_sp, handler_fp, |
| unhandled_exception, stacktrace); |
| } |
| UNREACHABLE(); |
| } |
| |
| // Static helpers for allocating, initializing, and throwing an error instance. |
| |
| // Return the script of the Dart function that called the native entry or the |
| // runtime entry. The frame iterator points to the callee. |
| RawScript* Exceptions::GetCallerScript(DartFrameIterator* iterator) { |
| StackFrame* caller_frame = iterator->NextFrame(); |
| ASSERT(caller_frame != NULL && caller_frame->IsDartFrame()); |
| const Function& caller = Function::Handle(caller_frame->LookupDartFunction()); |
| ASSERT(!caller.IsNull()); |
| return caller.script(); |
| } |
| |
| // Allocate a new instance of the given class name. |
| // TODO(hausner): Rename this NewCoreInstance to call out the fact that |
| // the class name is resolved in the core library implicitly? |
| RawInstance* Exceptions::NewInstance(const char* class_name) { |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| const String& cls_name = |
| String::Handle(zone, Symbols::New(thread, class_name)); |
| const Library& core_lib = Library::Handle(Library::CoreLibrary()); |
| // No ambiguity error expected: passing NULL. |
| Class& cls = Class::Handle(core_lib.LookupClass(cls_name)); |
| ASSERT(!cls.IsNull()); |
| // There are no parameterized error types, so no need to set type arguments. |
| return Instance::New(cls); |
| } |
| |
| // Allocate, initialize, and throw a TypeError or CastError. |
| // If error_msg is not null, throw a TypeError, even for a type cast. |
| void Exceptions::CreateAndThrowTypeError(TokenPosition location, |
| const AbstractType& src_type, |
| const AbstractType& dst_type, |
| const String& dst_name, |
| const String& bound_error_msg) { |
| ASSERT(!dst_name.IsNull()); // Pass Symbols::Empty() instead. |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| const Array& args = Array::Handle(zone, Array::New(4)); |
| |
| ExceptionType exception_type = |
| (bound_error_msg.IsNull() && |
| (dst_name.raw() == Symbols::InTypeCast().raw())) |
| ? kCast |
| : kType; |
| |
| DartFrameIterator iterator(thread, |
| StackFrameIterator::kNoCrossThreadIteration); |
| const Script& script = Script::Handle(zone, GetCallerScript(&iterator)); |
| intptr_t line = -1; |
| intptr_t column = -1; |
| ASSERT(!script.IsNull()); |
| if (location.IsReal()) { |
| if (script.HasSource() || script.kind() == RawScript::kKernelTag) { |
| script.GetTokenLocation(location, &line, &column); |
| } else { |
| script.GetTokenLocation(location, &line, NULL); |
| } |
| } |
| // Initialize '_url', '_line', and '_column' arguments. |
| args.SetAt(0, String::Handle(zone, script.url())); |
| args.SetAt(1, Smi::Handle(zone, Smi::New(line))); |
| args.SetAt(2, Smi::Handle(zone, Smi::New(column))); |
| |
| // Construct '_errorMsg'. |
| const GrowableObjectArray& pieces = |
| GrowableObjectArray::Handle(zone, GrowableObjectArray::New(20)); |
| |
| // Print bound error first, if any. |
| if (!bound_error_msg.IsNull() && (bound_error_msg.Length() > 0)) { |
| pieces.Add(bound_error_msg); |
| pieces.Add(Symbols::NewLine()); |
| } |
| |
| // If dst_type is malformed or malbounded, only print the embedded error. |
| if (!dst_type.IsNull()) { |
| const LanguageError& error = LanguageError::Handle(zone, dst_type.error()); |
| if (!error.IsNull()) { |
| // Print the embedded error only. |
| pieces.Add(String::Handle(zone, String::New(error.ToErrorCString()))); |
| pieces.Add(Symbols::NewLine()); |
| } else { |
| // Describe the type error. |
| if (!src_type.IsNull()) { |
| pieces.Add(Symbols::TypeQuote()); |
| pieces.Add(String::Handle(zone, src_type.UserVisibleName())); |
| pieces.Add(Symbols::QuoteIsNotASubtypeOf()); |
| } |
| pieces.Add(Symbols::TypeQuote()); |
| pieces.Add(String::Handle(zone, dst_type.UserVisibleName())); |
| pieces.Add(Symbols::SingleQuote()); |
| if (exception_type == kCast) { |
| pieces.Add(dst_name); |
| } else if (dst_name.Length() > 0) { |
| pieces.Add(Symbols::SpaceOfSpace()); |
| pieces.Add(Symbols::SingleQuote()); |
| pieces.Add(dst_name); |
| pieces.Add(Symbols::SingleQuote()); |
| } |
| // Print ambiguous URIs of src and dst types. |
| URIs uris(zone, 12); |
| if (!src_type.IsNull()) { |
| src_type.EnumerateURIs(&uris); |
| } |
| if (!dst_type.IsDynamicType() && !dst_type.IsVoidType()) { |
| dst_type.EnumerateURIs(&uris); |
| } |
| const String& formatted_uris = |
| String::Handle(zone, AbstractType::PrintURIs(&uris)); |
| if (formatted_uris.Length() > 0) { |
| pieces.Add(Symbols::SpaceWhereNewLine()); |
| pieces.Add(formatted_uris); |
| } |
| } |
| } |
| const Array& arr = Array::Handle(zone, Array::MakeFixedLength(pieces)); |
| const String& error_msg = String::Handle(zone, String::ConcatAll(arr)); |
| args.SetAt(3, error_msg); |
| |
| // Type errors in the core library may be difficult to diagnose. |
| // Print type error information before throwing the error when debugging. |
| if (FLAG_print_stacktrace_at_throw) { |
| THR_Print("'%s': Failed type check: line %" Pd " pos %" Pd ": ", |
| String::Handle(zone, script.url()).ToCString(), line, column); |
| THR_Print("%s\n", error_msg.ToCString()); |
| } |
| |
| // Throw TypeError or CastError instance. |
| Exceptions::ThrowByType(exception_type, args); |
| UNREACHABLE(); |
| } |
| |
| void Exceptions::Throw(Thread* thread, const Instance& exception) { |
| // Do not notify debugger on stack overflow and out of memory exceptions. |
| // The VM would crash when the debugger calls back into the VM to |
| // get values of variables. |
| #if !defined(PRODUCT) |
| Isolate* isolate = thread->isolate(); |
| if (exception.raw() != isolate->object_store()->out_of_memory() && |
| exception.raw() != isolate->object_store()->stack_overflow()) { |
| isolate->debugger()->PauseException(exception); |
| } |
| #endif |
| // Null object is a valid exception object. |
| ThrowExceptionHelper(thread, exception, StackTrace::Handle(thread->zone()), |
| false); |
| } |
| |
| void Exceptions::ReThrow(Thread* thread, |
| const Instance& exception, |
| const Instance& stacktrace) { |
| // Null object is a valid exception object. |
| ThrowExceptionHelper(thread, exception, stacktrace, true); |
| } |
| |
| void Exceptions::PropagateError(const Error& error) { |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| ASSERT(thread->top_exit_frame_info() != 0); |
| if (error.IsUnhandledException()) { |
| // If the error object represents an unhandled exception, then |
| // rethrow the exception in the normal fashion. |
| const UnhandledException& uhe = UnhandledException::Cast(error); |
| const Instance& exc = Instance::Handle(zone, uhe.exception()); |
| const Instance& stk = Instance::Handle(zone, uhe.stacktrace()); |
| Exceptions::ReThrow(thread, exc, stk); |
| } else { |
| // Return to the invocation stub and return this error object. The |
| // C++ code which invoked this dart sequence can check and do the |
| // appropriate thing. |
| uword handler_pc = 0; |
| uword handler_sp = 0; |
| uword handler_fp = 0; |
| FindErrorHandler(&handler_pc, &handler_sp, &handler_fp); |
| JumpToExceptionHandler(thread, handler_pc, handler_sp, handler_fp, error, |
| StackTrace::Handle(zone)); // Null stacktrace. |
| } |
| UNREACHABLE(); |
| } |
| |
| void Exceptions::PropagateToEntry(const Error& error) { |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| ASSERT(thread->top_exit_frame_info() != 0); |
| Instance& stacktrace = Instance::Handle(zone); |
| if (error.IsUnhandledException()) { |
| const UnhandledException& uhe = UnhandledException::Cast(error); |
| stacktrace = uhe.stacktrace(); |
| } else { |
| stacktrace = Exceptions::CurrentStackTrace(); |
| } |
| uword handler_pc = 0; |
| uword handler_sp = 0; |
| uword handler_fp = 0; |
| FindErrorHandler(&handler_pc, &handler_sp, &handler_fp); |
| JumpToExceptionHandler(thread, handler_pc, handler_sp, handler_fp, error, |
| stacktrace); |
| UNREACHABLE(); |
| } |
| |
| void Exceptions::ThrowByType(ExceptionType type, const Array& arguments) { |
| Thread* thread = Thread::Current(); |
| const Object& result = |
| Object::Handle(thread->zone(), Create(type, arguments)); |
| if (result.IsError()) { |
| // We got an error while constructing the exception object. |
| // Propagate the error instead of throwing the exception. |
| PropagateError(Error::Cast(result)); |
| } else { |
| ASSERT(result.IsInstance()); |
| Throw(thread, Instance::Cast(result)); |
| } |
| } |
| |
| void Exceptions::ThrowOOM() { |
| Thread* thread = Thread::Current(); |
| Isolate* isolate = thread->isolate(); |
| const Instance& oom = Instance::Handle( |
| thread->zone(), isolate->object_store()->out_of_memory()); |
| Throw(thread, oom); |
| } |
| |
| void Exceptions::ThrowStackOverflow() { |
| Thread* thread = Thread::Current(); |
| Isolate* isolate = thread->isolate(); |
| const Instance& stack_overflow = Instance::Handle( |
| thread->zone(), isolate->object_store()->stack_overflow()); |
| Throw(thread, stack_overflow); |
| } |
| |
| void Exceptions::ThrowArgumentError(const Instance& arg) { |
| const Array& args = Array::Handle(Array::New(1)); |
| args.SetAt(0, arg); |
| Exceptions::ThrowByType(Exceptions::kArgument, args); |
| } |
| |
| void Exceptions::ThrowRangeError(const char* argument_name, |
| const Integer& argument_value, |
| intptr_t expected_from, |
| intptr_t expected_to) { |
| const Array& args = Array::Handle(Array::New(4)); |
| args.SetAt(0, argument_value); |
| args.SetAt(1, Integer::Handle(Integer::New(expected_from))); |
| args.SetAt(2, Integer::Handle(Integer::New(expected_to))); |
| args.SetAt(3, String::Handle(String::New(argument_name))); |
| Exceptions::ThrowByType(Exceptions::kRange, args); |
| } |
| |
| void Exceptions::ThrowRangeErrorMsg(const char* msg) { |
| const Array& args = Array::Handle(Array::New(1)); |
| args.SetAt(0, String::Handle(String::New(msg))); |
| Exceptions::ThrowByType(Exceptions::kRangeMsg, args); |
| } |
| |
| void Exceptions::ThrowCompileTimeError(const LanguageError& error) { |
| const Array& args = Array::Handle(Array::New(1)); |
| args.SetAt(0, String::Handle(error.FormatMessage())); |
| Exceptions::ThrowByType(Exceptions::kCompileTimeError, args); |
| } |
| |
| RawObject* Exceptions::Create(ExceptionType type, const Array& arguments) { |
| Library& library = Library::Handle(); |
| const String* class_name = NULL; |
| const String* constructor_name = &Symbols::Dot(); |
| switch (type) { |
| case kNone: |
| case kStackOverflow: |
| case kOutOfMemory: |
| UNREACHABLE(); |
| break; |
| case kRange: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::RangeError(); |
| constructor_name = &Symbols::DotRange(); |
| break; |
| case kRangeMsg: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::RangeError(); |
| constructor_name = &Symbols::Dot(); |
| break; |
| case kArgument: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::ArgumentError(); |
| break; |
| case kArgumentValue: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::ArgumentError(); |
| constructor_name = &Symbols::DotValue(); |
| break; |
| case kIntegerDivisionByZeroException: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::IntegerDivisionByZeroException(); |
| break; |
| case kNoSuchMethod: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::NoSuchMethodError(); |
| constructor_name = &Symbols::DotWithType(); |
| break; |
| case kFormat: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::FormatException(); |
| break; |
| case kUnsupported: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::UnsupportedError(); |
| break; |
| case kNullThrown: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::NullThrownError(); |
| break; |
| case kIsolateSpawn: |
| library = Library::IsolateLibrary(); |
| class_name = &Symbols::IsolateSpawnException(); |
| break; |
| case kAssertion: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::AssertionError(); |
| constructor_name = &Symbols::DotCreate(); |
| break; |
| case kCast: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::CastError(); |
| constructor_name = &Symbols::DotCreate(); |
| break; |
| case kType: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::TypeError(); |
| constructor_name = &Symbols::DotCreate(); |
| break; |
| case kFallThrough: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::FallThroughError(); |
| constructor_name = &Symbols::DotCreate(); |
| break; |
| case kAbstractClassInstantiation: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::AbstractClassInstantiationError(); |
| constructor_name = &Symbols::DotCreate(); |
| break; |
| case kCyclicInitializationError: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::CyclicInitializationError(); |
| break; |
| case kCompileTimeError: |
| library = Library::CoreLibrary(); |
| class_name = &Symbols::_CompileTimeError(); |
| break; |
| } |
| |
| Thread* thread = Thread::Current(); |
| NoReloadScope no_reload_scope(thread->isolate(), thread); |
| return DartLibraryCalls::InstanceCreate(library, *class_name, |
| *constructor_name, arguments); |
| } |
| |
| } // namespace dart |
