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Diffstat (limited to 'src/3rdparty/v8/src/top.cc')
| -rw-r--r-- | src/3rdparty/v8/src/top.cc | 993 |
1 files changed, 993 insertions, 0 deletions
diff --git a/src/3rdparty/v8/src/top.cc b/src/3rdparty/v8/src/top.cc new file mode 100644 index 0000000..abd4ece --- /dev/null +++ b/src/3rdparty/v8/src/top.cc @@ -0,0 +1,993 @@ +// Copyright 2006-2008 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "v8.h" + +#include "api.h" +#include "bootstrapper.h" +#include "compiler.h" +#include "debug.h" +#include "execution.h" +#include "messages.h" +#include "platform.h" +#include "simulator.h" +#include "string-stream.h" +#include "vm-state-inl.h" + + +// TODO(isolates): move to isolate.cc. This stuff is kept here to +// simplify merging. + +namespace v8 { +namespace internal { + +v8::TryCatch* ThreadLocalTop::TryCatchHandler() { + return TRY_CATCH_FROM_ADDRESS(try_catch_handler_address()); +} + + +void ThreadLocalTop::Initialize() { + c_entry_fp_ = 0; + handler_ = 0; +#ifdef USE_SIMULATOR +#ifdef V8_TARGET_ARCH_ARM + simulator_ = Simulator::current(Isolate::Current()); +#elif V8_TARGET_ARCH_MIPS + simulator_ = Simulator::current(Isolate::Current()); +#endif +#endif +#ifdef ENABLE_LOGGING_AND_PROFILING + js_entry_sp_ = NULL; + external_callback_ = NULL; +#endif +#ifdef ENABLE_VMSTATE_TRACKING + current_vm_state_ = EXTERNAL; +#endif + try_catch_handler_address_ = NULL; + context_ = NULL; + int id = Isolate::Current()->thread_manager()->CurrentId(); + thread_id_ = (id == 0) ? ThreadManager::kInvalidId : id; + external_caught_exception_ = false; + failed_access_check_callback_ = NULL; + save_context_ = NULL; + catcher_ = NULL; +} + + +Address Isolate::get_address_from_id(Isolate::AddressId id) { + return isolate_addresses_[id]; +} + + +char* Isolate::Iterate(ObjectVisitor* v, char* thread_storage) { + ThreadLocalTop* thread = reinterpret_cast<ThreadLocalTop*>(thread_storage); + Iterate(v, thread); + return thread_storage + sizeof(ThreadLocalTop); +} + + +void Isolate::IterateThread(ThreadVisitor* v) { + v->VisitThread(this, thread_local_top()); +} + + +void Isolate::IterateThread(ThreadVisitor* v, char* t) { + ThreadLocalTop* thread = reinterpret_cast<ThreadLocalTop*>(t); + v->VisitThread(this, thread); +} + + +void Isolate::Iterate(ObjectVisitor* v, ThreadLocalTop* thread) { + // Visit the roots from the top for a given thread. + Object* pending; + // The pending exception can sometimes be a failure. We can't show + // that to the GC, which only understands objects. + if (thread->pending_exception_->ToObject(&pending)) { + v->VisitPointer(&pending); + thread->pending_exception_ = pending; // In case GC updated it. + } + v->VisitPointer(&(thread->pending_message_obj_)); + v->VisitPointer(BitCast<Object**>(&(thread->pending_message_script_))); + v->VisitPointer(BitCast<Object**>(&(thread->context_))); + Object* scheduled; + if (thread->scheduled_exception_->ToObject(&scheduled)) { + v->VisitPointer(&scheduled); + thread->scheduled_exception_ = scheduled; + } + + for (v8::TryCatch* block = thread->TryCatchHandler(); + block != NULL; + block = TRY_CATCH_FROM_ADDRESS(block->next_)) { + v->VisitPointer(BitCast<Object**>(&(block->exception_))); + v->VisitPointer(BitCast<Object**>(&(block->message_))); + } + + // Iterate over pointers on native execution stack. + for (StackFrameIterator it(this, thread); !it.done(); it.Advance()) { + it.frame()->Iterate(v); + } +} + + +void Isolate::Iterate(ObjectVisitor* v) { + ThreadLocalTop* current_t = thread_local_top(); + Iterate(v, current_t); +} + + +void Isolate::RegisterTryCatchHandler(v8::TryCatch* that) { + // The ARM simulator has a separate JS stack. We therefore register + // the C++ try catch handler with the simulator and get back an + // address that can be used for comparisons with addresses into the + // JS stack. When running without the simulator, the address + // returned will be the address of the C++ try catch handler itself. + Address address = reinterpret_cast<Address>( + SimulatorStack::RegisterCTryCatch(reinterpret_cast<uintptr_t>(that))); + thread_local_top()->set_try_catch_handler_address(address); +} + + +void Isolate::UnregisterTryCatchHandler(v8::TryCatch* that) { + ASSERT(thread_local_top()->TryCatchHandler() == that); + thread_local_top()->set_try_catch_handler_address( + reinterpret_cast<Address>(that->next_)); + thread_local_top()->catcher_ = NULL; + SimulatorStack::UnregisterCTryCatch(); +} + + +Handle<String> Isolate::StackTraceString() { + if (stack_trace_nesting_level_ == 0) { + stack_trace_nesting_level_++; + HeapStringAllocator allocator; + StringStream::ClearMentionedObjectCache(); + StringStream accumulator(&allocator); + incomplete_message_ = &accumulator; + PrintStack(&accumulator); + Handle<String> stack_trace = accumulator.ToString(); + incomplete_message_ = NULL; + stack_trace_nesting_level_ = 0; + return stack_trace; + } else if (stack_trace_nesting_level_ == 1) { + stack_trace_nesting_level_++; + OS::PrintError( + "\n\nAttempt to print stack while printing stack (double fault)\n"); + OS::PrintError( + "If you are lucky you may find a partial stack dump on stdout.\n\n"); + incomplete_message_->OutputToStdOut(); + return factory()->empty_symbol(); + } else { + OS::Abort(); + // Unreachable + return factory()->empty_symbol(); + } +} + + +Handle<JSArray> Isolate::CaptureCurrentStackTrace( + int frame_limit, StackTrace::StackTraceOptions options) { + // Ensure no negative values. + int limit = Max(frame_limit, 0); + Handle<JSArray> stack_trace = factory()->NewJSArray(frame_limit); + + Handle<String> column_key = factory()->LookupAsciiSymbol("column"); + Handle<String> line_key = factory()->LookupAsciiSymbol("lineNumber"); + Handle<String> script_key = factory()->LookupAsciiSymbol("scriptName"); +#ifdef QT_BUILD_SCRIPT_LIB + Handle<String> script_id_key = factory()->LookupAsciiSymbol("scriptId"); +#endif + Handle<String> name_or_source_url_key = + factory()->LookupAsciiSymbol("nameOrSourceURL"); + Handle<String> script_name_or_source_url_key = + factory()->LookupAsciiSymbol("scriptNameOrSourceURL"); + Handle<String> function_key = factory()->LookupAsciiSymbol("functionName"); + Handle<String> eval_key = factory()->LookupAsciiSymbol("isEval"); + Handle<String> constructor_key = + factory()->LookupAsciiSymbol("isConstructor"); + + StackTraceFrameIterator it(this); + int frames_seen = 0; + while (!it.done() && (frames_seen < limit)) { + JavaScriptFrame* frame = it.frame(); + // Set initial size to the maximum inlining level + 1 for the outermost + // function. + List<FrameSummary> frames(Compiler::kMaxInliningLevels + 1); + frame->Summarize(&frames); + for (int i = frames.length() - 1; i >= 0 && frames_seen < limit; i--) { + // Create a JSObject to hold the information for the StackFrame. + Handle<JSObject> stackFrame = factory()->NewJSObject(object_function()); + + Handle<JSFunction> fun = frames[i].function(); + Handle<Script> script(Script::cast(fun->shared()->script())); + + if (options & StackTrace::kLineNumber) { + int script_line_offset = script->line_offset()->value(); + int position = frames[i].code()->SourcePosition(frames[i].pc()); + int line_number = GetScriptLineNumber(script, position); + // line_number is already shifted by the script_line_offset. + int relative_line_number = line_number - script_line_offset; + if (options & StackTrace::kColumnOffset && relative_line_number >= 0) { + Handle<FixedArray> line_ends(FixedArray::cast(script->line_ends())); + int start = (relative_line_number == 0) ? 0 : + Smi::cast(line_ends->get(relative_line_number - 1))->value() + 1; + int column_offset = position - start; + if (relative_line_number == 0) { + // For the case where the code is on the same line as the script + // tag. + column_offset += script->column_offset()->value(); + } + SetLocalPropertyNoThrow(stackFrame, column_key, + Handle<Smi>(Smi::FromInt(column_offset + 1))); + } + SetLocalPropertyNoThrow(stackFrame, line_key, + Handle<Smi>(Smi::FromInt(line_number + 1))); + } + + if (options & StackTrace::kScriptName) { + Handle<Object> script_name(script->name(), this); + SetLocalPropertyNoThrow(stackFrame, script_key, script_name); + } + +#ifdef QT_BUILD_SCRIPT_LIB + if (options & StackTrace::kScriptId) { + Handle<Object> script_id(script->id()); + SetLocalPropertyNoThrow(stackFrame, script_id_key, script_id); + } +#endif + + if (options & StackTrace::kScriptNameOrSourceURL) { + Handle<Object> script_name(script->name(), this); + Handle<JSValue> script_wrapper = GetScriptWrapper(script); + Handle<Object> property = GetProperty(script_wrapper, + name_or_source_url_key); + ASSERT(property->IsJSFunction()); + Handle<JSFunction> method = Handle<JSFunction>::cast(property); + bool caught_exception; + Handle<Object> result = Execution::TryCall(method, script_wrapper, 0, + NULL, &caught_exception); + if (caught_exception) { + result = factory()->undefined_value(); + } + SetLocalPropertyNoThrow(stackFrame, script_name_or_source_url_key, + result); + } + + if (options & StackTrace::kFunctionName) { + Handle<Object> fun_name(fun->shared()->name(), this); + if (fun_name->ToBoolean()->IsFalse()) { + fun_name = Handle<Object>(fun->shared()->inferred_name(), this); + } + SetLocalPropertyNoThrow(stackFrame, function_key, fun_name); + } + + if (options & StackTrace::kIsEval) { + int type = Smi::cast(script->compilation_type())->value(); + Handle<Object> is_eval = (type == Script::COMPILATION_TYPE_EVAL) ? + factory()->true_value() : factory()->false_value(); + SetLocalPropertyNoThrow(stackFrame, eval_key, is_eval); + } + + if (options & StackTrace::kIsConstructor) { + Handle<Object> is_constructor = (frames[i].is_constructor()) ? + factory()->true_value() : factory()->false_value(); + SetLocalPropertyNoThrow(stackFrame, constructor_key, is_constructor); + } + + FixedArray::cast(stack_trace->elements())->set(frames_seen, *stackFrame); + frames_seen++; + } + it.Advance(); + } + + stack_trace->set_length(Smi::FromInt(frames_seen)); + return stack_trace; +} + + +void Isolate::PrintStack() { + if (stack_trace_nesting_level_ == 0) { + stack_trace_nesting_level_++; + + StringAllocator* allocator; + if (preallocated_message_space_ == NULL) { + allocator = new HeapStringAllocator(); + } else { + allocator = preallocated_message_space_; + } + + StringStream::ClearMentionedObjectCache(); + StringStream accumulator(allocator); + incomplete_message_ = &accumulator; + PrintStack(&accumulator); + accumulator.OutputToStdOut(); + accumulator.Log(); + incomplete_message_ = NULL; + stack_trace_nesting_level_ = 0; + if (preallocated_message_space_ == NULL) { + // Remove the HeapStringAllocator created above. + delete allocator; + } + } else if (stack_trace_nesting_level_ == 1) { + stack_trace_nesting_level_++; + OS::PrintError( + "\n\nAttempt to print stack while printing stack (double fault)\n"); + OS::PrintError( + "If you are lucky you may find a partial stack dump on stdout.\n\n"); + incomplete_message_->OutputToStdOut(); + } +} + + +static void PrintFrames(StringStream* accumulator, + StackFrame::PrintMode mode) { + StackFrameIterator it; + for (int i = 0; !it.done(); it.Advance()) { + it.frame()->Print(accumulator, mode, i++); + } +} + + +void Isolate::PrintStack(StringStream* accumulator) { + if (!IsInitialized()) { + accumulator->Add( + "\n==== Stack trace is not available ==========================\n\n"); + accumulator->Add( + "\n==== Isolate for the thread is not initialized =============\n\n"); + return; + } + // The MentionedObjectCache is not GC-proof at the moment. + AssertNoAllocation nogc; + ASSERT(StringStream::IsMentionedObjectCacheClear()); + + // Avoid printing anything if there are no frames. + if (c_entry_fp(thread_local_top()) == 0) return; + + accumulator->Add( + "\n==== Stack trace ============================================\n\n"); + PrintFrames(accumulator, StackFrame::OVERVIEW); + + accumulator->Add( + "\n==== Details ================================================\n\n"); + PrintFrames(accumulator, StackFrame::DETAILS); + + accumulator->PrintMentionedObjectCache(); + accumulator->Add("=====================\n\n"); +} + + +void Isolate::SetFailedAccessCheckCallback( + v8::FailedAccessCheckCallback callback) { + thread_local_top()->failed_access_check_callback_ = callback; +} + + +void Isolate::ReportFailedAccessCheck(JSObject* receiver, v8::AccessType type) { + if (!thread_local_top()->failed_access_check_callback_) return; + + ASSERT(receiver->IsAccessCheckNeeded()); + ASSERT(context()); + + // Get the data object from access check info. + JSFunction* constructor = JSFunction::cast(receiver->map()->constructor()); + if (!constructor->shared()->IsApiFunction()) return; + Object* data_obj = + constructor->shared()->get_api_func_data()->access_check_info(); + if (data_obj == heap_.undefined_value()) return; + + HandleScope scope; + Handle<JSObject> receiver_handle(receiver); + Handle<Object> data(AccessCheckInfo::cast(data_obj)->data()); + thread_local_top()->failed_access_check_callback_( + v8::Utils::ToLocal(receiver_handle), + type, + v8::Utils::ToLocal(data)); +} + + +enum MayAccessDecision { + YES, NO, UNKNOWN +}; + + +static MayAccessDecision MayAccessPreCheck(Isolate* isolate, + JSObject* receiver, + v8::AccessType type) { + // During bootstrapping, callback functions are not enabled yet. + if (isolate->bootstrapper()->IsActive()) return YES; + + if (receiver->IsJSGlobalProxy()) { + Object* receiver_context = JSGlobalProxy::cast(receiver)->context(); + if (!receiver_context->IsContext()) return NO; + + // Get the global context of current top context. + // avoid using Isolate::global_context() because it uses Handle. + Context* global_context = isolate->context()->global()->global_context(); + if (receiver_context == global_context) return YES; + + if (Context::cast(receiver_context)->security_token() == + global_context->security_token()) + return YES; + } + + return UNKNOWN; +} + + +bool Isolate::MayNamedAccess(JSObject* receiver, Object* key, + v8::AccessType type) { + ASSERT(receiver->IsAccessCheckNeeded()); + + // The callers of this method are not expecting a GC. + AssertNoAllocation no_gc; + + // Skip checks for hidden properties access. Note, we do not + // require existence of a context in this case. + if (key == heap_.hidden_symbol()) return true; + + // Check for compatibility between the security tokens in the + // current lexical context and the accessed object. + ASSERT(context()); + + MayAccessDecision decision = MayAccessPreCheck(this, receiver, type); + if (decision != UNKNOWN) return decision == YES; + + // Get named access check callback + JSFunction* constructor = JSFunction::cast(receiver->map()->constructor()); + if (!constructor->shared()->IsApiFunction()) return false; + + Object* data_obj = + constructor->shared()->get_api_func_data()->access_check_info(); + if (data_obj == heap_.undefined_value()) return false; + + Object* fun_obj = AccessCheckInfo::cast(data_obj)->named_callback(); + v8::NamedSecurityCallback callback = + v8::ToCData<v8::NamedSecurityCallback>(fun_obj); + + if (!callback) return false; + + HandleScope scope(this); + Handle<JSObject> receiver_handle(receiver, this); + Handle<Object> key_handle(key, this); + Handle<Object> data(AccessCheckInfo::cast(data_obj)->data(), this); + LOG(this, ApiNamedSecurityCheck(key)); + bool result = false; + { + // Leaving JavaScript. + VMState state(this, EXTERNAL); + result = callback(v8::Utils::ToLocal(receiver_handle), + v8::Utils::ToLocal(key_handle), + type, + v8::Utils::ToLocal(data)); + } + return result; +} + + +bool Isolate::MayIndexedAccess(JSObject* receiver, + uint32_t index, + v8::AccessType type) { + ASSERT(receiver->IsAccessCheckNeeded()); + // Check for compatibility between the security tokens in the + // current lexical context and the accessed object. + ASSERT(context()); + + MayAccessDecision decision = MayAccessPreCheck(this, receiver, type); + if (decision != UNKNOWN) return decision == YES; + + // Get indexed access check callback + JSFunction* constructor = JSFunction::cast(receiver->map()->constructor()); + if (!constructor->shared()->IsApiFunction()) return false; + + Object* data_obj = + constructor->shared()->get_api_func_data()->access_check_info(); + if (data_obj == heap_.undefined_value()) return false; + + Object* fun_obj = AccessCheckInfo::cast(data_obj)->indexed_callback(); + v8::IndexedSecurityCallback callback = + v8::ToCData<v8::IndexedSecurityCallback>(fun_obj); + + if (!callback) return false; + + HandleScope scope(this); + Handle<JSObject> receiver_handle(receiver, this); + Handle<Object> data(AccessCheckInfo::cast(data_obj)->data(), this); + LOG(this, ApiIndexedSecurityCheck(index)); + bool result = false; + { + // Leaving JavaScript. + VMState state(this, EXTERNAL); + result = callback(v8::Utils::ToLocal(receiver_handle), + index, + type, + v8::Utils::ToLocal(data)); + } + return result; +} + + +const char* const Isolate::kStackOverflowMessage = + "Uncaught RangeError: Maximum call stack size exceeded"; + + +Failure* Isolate::StackOverflow() { + HandleScope scope; + Handle<String> key = factory()->stack_overflow_symbol(); + Handle<JSObject> boilerplate = + Handle<JSObject>::cast(GetProperty(js_builtins_object(), key)); + Handle<Object> exception = Copy(boilerplate); + // TODO(1240995): To avoid having to call JavaScript code to compute + // the message for stack overflow exceptions which is very likely to + // double fault with another stack overflow exception, we use a + // precomputed message. + DoThrow(*exception, NULL, kStackOverflowMessage); + return Failure::Exception(); +} + + +Failure* Isolate::TerminateExecution() { + DoThrow(heap_.termination_exception(), NULL, NULL); + return Failure::Exception(); +} + + +Failure* Isolate::Throw(Object* exception, MessageLocation* location) { + DoThrow(exception, location, NULL); + return Failure::Exception(); +} + + +Failure* Isolate::ReThrow(MaybeObject* exception, MessageLocation* location) { + bool can_be_caught_externally = false; + ShouldReportException(&can_be_caught_externally, + is_catchable_by_javascript(exception)); + thread_local_top()->catcher_ = can_be_caught_externally ? + try_catch_handler() : NULL; + + // Set the exception being re-thrown. + set_pending_exception(exception); + return Failure::Exception(); +} + + +Failure* Isolate::ThrowIllegalOperation() { + return Throw(heap_.illegal_access_symbol()); +} + + +void Isolate::ScheduleThrow(Object* exception) { + // When scheduling a throw we first throw the exception to get the + // error reporting if it is uncaught before rescheduling it. + Throw(exception); + thread_local_top()->scheduled_exception_ = pending_exception(); + thread_local_top()->external_caught_exception_ = false; + clear_pending_exception(); +} + + +Failure* Isolate::PromoteScheduledException() { + MaybeObject* thrown = scheduled_exception(); + clear_scheduled_exception(); + // Re-throw the exception to avoid getting repeated error reporting. + return ReThrow(thrown); +} + + +void Isolate::PrintCurrentStackTrace(FILE* out) { + StackTraceFrameIterator it(this); + while (!it.done()) { + HandleScope scope; + // Find code position if recorded in relocation info. + JavaScriptFrame* frame = it.frame(); + int pos = frame->LookupCode()->SourcePosition(frame->pc()); + Handle<Object> pos_obj(Smi::FromInt(pos)); + // Fetch function and receiver. + Handle<JSFunction> fun(JSFunction::cast(frame->function())); + Handle<Object> recv(frame->receiver()); + // Advance to the next JavaScript frame and determine if the + // current frame is the top-level frame. + it.Advance(); + Handle<Object> is_top_level = it.done() + ? factory()->true_value() + : factory()->false_value(); + // Generate and print stack trace line. + Handle<String> line = + Execution::GetStackTraceLine(recv, fun, pos_obj, is_top_level); + if (line->length() > 0) { + line->PrintOn(out); + fprintf(out, "\n"); + } + } +} + + +void Isolate::ComputeLocation(MessageLocation* target) { + *target = MessageLocation(Handle<Script>(heap_.empty_script()), -1, -1); + StackTraceFrameIterator it(this); + if (!it.done()) { + JavaScriptFrame* frame = it.frame(); + JSFunction* fun = JSFunction::cast(frame->function()); + Object* script = fun->shared()->script(); + if (script->IsScript() && + !(Script::cast(script)->source()->IsUndefined())) { + int pos = frame->LookupCode()->SourcePosition(frame->pc()); + // Compute the location from the function and the reloc info. + Handle<Script> casted_script(Script::cast(script)); + *target = MessageLocation(casted_script, pos, pos + 1); + } + } +} + + +bool Isolate::ShouldReportException(bool* can_be_caught_externally, + bool catchable_by_javascript) { + // Find the top-most try-catch handler. + StackHandler* handler = + StackHandler::FromAddress(Isolate::handler(thread_local_top())); + while (handler != NULL && !handler->is_try_catch()) { + handler = handler->next(); + } + + // Get the address of the external handler so we can compare the address to + // determine which one is closer to the top of the stack. + Address external_handler_address = + thread_local_top()->try_catch_handler_address(); + + // The exception has been externally caught if and only if there is + // an external handler which is on top of the top-most try-catch + // handler. + *can_be_caught_externally = external_handler_address != NULL && + (handler == NULL || handler->address() > external_handler_address || + !catchable_by_javascript); + + if (*can_be_caught_externally) { + // Only report the exception if the external handler is verbose. + return try_catch_handler()->is_verbose_; + } else { + // Report the exception if it isn't caught by JavaScript code. + return handler == NULL; + } +} + + +void Isolate::DoThrow(MaybeObject* exception, + MessageLocation* location, + const char* message) { + ASSERT(!has_pending_exception()); + + HandleScope scope; + Object* exception_object = Smi::FromInt(0); + bool is_object = exception->ToObject(&exception_object); + Handle<Object> exception_handle(exception_object); + + // Determine reporting and whether the exception is caught externally. + bool catchable_by_javascript = is_catchable_by_javascript(exception); + // Only real objects can be caught by JS. + ASSERT(!catchable_by_javascript || is_object); + bool can_be_caught_externally = false; + bool should_report_exception = + ShouldReportException(&can_be_caught_externally, catchable_by_javascript); + bool report_exception = catchable_by_javascript && should_report_exception; + +#ifdef ENABLE_DEBUGGER_SUPPORT + // Notify debugger of exception. + if (catchable_by_javascript) { + debugger_->OnException(exception_handle, report_exception); + } +#endif + + // Generate the message. + Handle<Object> message_obj; + MessageLocation potential_computed_location; + bool try_catch_needs_message = + can_be_caught_externally && + try_catch_handler()->capture_message_; + if (report_exception || try_catch_needs_message) { + if (location == NULL) { + // If no location was specified we use a computed one instead + ComputeLocation(&potential_computed_location); + location = &potential_computed_location; + } + if (!bootstrapper()->IsActive()) { + // It's not safe to try to make message objects or collect stack + // traces while the bootstrapper is active since the infrastructure + // may not have been properly initialized. + Handle<String> stack_trace; + if (FLAG_trace_exception) stack_trace = StackTraceString(); + Handle<JSArray> stack_trace_object; + if (report_exception && capture_stack_trace_for_uncaught_exceptions_) { + stack_trace_object = CaptureCurrentStackTrace( + stack_trace_for_uncaught_exceptions_frame_limit_, + stack_trace_for_uncaught_exceptions_options_); + } + ASSERT(is_object); // Can't use the handle unless there's a real object. + message_obj = MessageHandler::MakeMessageObject("uncaught_exception", + location, HandleVector<Object>(&exception_handle, 1), stack_trace, + stack_trace_object); + } + } + + // Save the message for reporting if the the exception remains uncaught. + thread_local_top()->has_pending_message_ = report_exception; + thread_local_top()->pending_message_ = message; + if (!message_obj.is_null()) { + thread_local_top()->pending_message_obj_ = *message_obj; + if (location != NULL) { + thread_local_top()->pending_message_script_ = *location->script(); + thread_local_top()->pending_message_start_pos_ = location->start_pos(); + thread_local_top()->pending_message_end_pos_ = location->end_pos(); + } + } + + // Do not forget to clean catcher_ if currently thrown exception cannot + // be caught. If necessary, ReThrow will update the catcher. + thread_local_top()->catcher_ = can_be_caught_externally ? + try_catch_handler() : NULL; + + // NOTE: Notifying the debugger or generating the message + // may have caused new exceptions. For now, we just ignore + // that and set the pending exception to the original one. + if (is_object) { + set_pending_exception(*exception_handle); + } else { + // Failures are not on the heap so they neither need nor work with handles. + ASSERT(exception_handle->IsFailure()); + set_pending_exception(exception); + } +} + + +bool Isolate::IsExternallyCaught() { + ASSERT(has_pending_exception()); + + if ((thread_local_top()->catcher_ == NULL) || + (try_catch_handler() != thread_local_top()->catcher_)) { + // When throwing the exception, we found no v8::TryCatch + // which should care about this exception. + return false; + } + + if (!is_catchable_by_javascript(pending_exception())) { + return true; + } + + // Get the address of the external handler so we can compare the address to + // determine which one is closer to the top of the stack. + Address external_handler_address = + thread_local_top()->try_catch_handler_address(); + ASSERT(external_handler_address != NULL); + + // The exception has been externally caught if and only if there is + // an external handler which is on top of the top-most try-finally + // handler. + // There should be no try-catch blocks as they would prohibit us from + // finding external catcher in the first place (see catcher_ check above). + // + // Note, that finally clause would rethrow an exception unless it's + // aborted by jumps in control flow like return, break, etc. and we'll + // have another chances to set proper v8::TryCatch. + StackHandler* handler = + StackHandler::FromAddress(Isolate::handler(thread_local_top())); + while (handler != NULL && handler->address() < external_handler_address) { + ASSERT(!handler->is_try_catch()); + if (handler->is_try_finally()) return false; + + handler = handler->next(); + } + + return true; +} + + +void Isolate::ReportPendingMessages() { + ASSERT(has_pending_exception()); + // If the pending exception is OutOfMemoryException set out_of_memory in + // the global context. Note: We have to mark the global context here + // since the GenerateThrowOutOfMemory stub cannot make a RuntimeCall to + // set it. + bool external_caught = IsExternallyCaught(); + thread_local_top()->external_caught_exception_ = external_caught; + HandleScope scope(this); + if (thread_local_top()->pending_exception_ == + Failure::OutOfMemoryException()) { + context()->mark_out_of_memory(); + } else if (thread_local_top()->pending_exception_ == + heap_.termination_exception()) { + if (external_caught) { + try_catch_handler()->can_continue_ = false; + try_catch_handler()->exception_ = heap_.null_value(); + } + } else { + // At this point all non-object (failure) exceptions have + // been dealt with so this shouldn't fail. + Object* pending_exception_object = pending_exception()->ToObjectUnchecked(); + Handle<Object> exception(pending_exception_object); + thread_local_top()->external_caught_exception_ = false; + if (external_caught) { + try_catch_handler()->can_continue_ = true; + try_catch_handler()->exception_ = thread_local_top()->pending_exception_; + if (!thread_local_top()->pending_message_obj_->IsTheHole()) { + try_catch_handler()->message_ = + thread_local_top()->pending_message_obj_; + } + } + if (thread_local_top()->has_pending_message_) { + thread_local_top()->has_pending_message_ = false; + if (thread_local_top()->pending_message_ != NULL) { + MessageHandler::ReportMessage(thread_local_top()->pending_message_); + } else if (!thread_local_top()->pending_message_obj_->IsTheHole()) { + Handle<Object> message_obj(thread_local_top()->pending_message_obj_); + if (thread_local_top()->pending_message_script_ != NULL) { + Handle<Script> script(thread_local_top()->pending_message_script_); + int start_pos = thread_local_top()->pending_message_start_pos_; + int end_pos = thread_local_top()->pending_message_end_pos_; + MessageLocation location(script, start_pos, end_pos); + MessageHandler::ReportMessage(&location, message_obj); + } else { + MessageHandler::ReportMessage(NULL, message_obj); + } + } + } + thread_local_top()->external_caught_exception_ = external_caught; + set_pending_exception(*exception); + } + clear_pending_message(); +} + + +void Isolate::TraceException(bool flag) { + FLAG_trace_exception = flag; // TODO(isolates): This is an unfortunate use. +} + + +bool Isolate::OptionalRescheduleException(bool is_bottom_call) { + // Allways reschedule out of memory exceptions. + if (!is_out_of_memory()) { + bool is_termination_exception = + pending_exception() == heap_.termination_exception(); + + // Do not reschedule the exception if this is the bottom call. + bool clear_exception = is_bottom_call; + + if (is_termination_exception) { + if (is_bottom_call) { + thread_local_top()->external_caught_exception_ = false; + clear_pending_exception(); + return false; + } + } else if (thread_local_top()->external_caught_exception_) { + // If the exception is externally caught, clear it if there are no + // JavaScript frames on the way to the C++ frame that has the + // external handler. + ASSERT(thread_local_top()->try_catch_handler_address() != NULL); + Address external_handler_address = + thread_local_top()->try_catch_handler_address(); + JavaScriptFrameIterator it; + if (it.done() || (it.frame()->sp() > external_handler_address)) { + clear_exception = true; + } + } + + // Clear the exception if needed. + if (clear_exception) { + thread_local_top()->external_caught_exception_ = false; + clear_pending_exception(); + return false; + } + } + + // Reschedule the exception. + thread_local_top()->scheduled_exception_ = pending_exception(); + clear_pending_exception(); + return true; +} + + +void Isolate::SetCaptureStackTraceForUncaughtExceptions( + bool capture, + int frame_limit, + StackTrace::StackTraceOptions options) { + capture_stack_trace_for_uncaught_exceptions_ = capture; + stack_trace_for_uncaught_exceptions_frame_limit_ = frame_limit; + stack_trace_for_uncaught_exceptions_options_ = options; +} + + +bool Isolate::is_out_of_memory() { + if (has_pending_exception()) { + MaybeObject* e = pending_exception(); + if (e->IsFailure() && Failure::cast(e)->IsOutOfMemoryException()) { + return true; + } + } + if (has_scheduled_exception()) { + MaybeObject* e = scheduled_exception(); + if (e->IsFailure() && Failure::cast(e)->IsOutOfMemoryException()) { + return true; + } + } + return false; +} + + +Handle<Context> Isolate::global_context() { + GlobalObject* global = thread_local_top()->context_->global(); + return Handle<Context>(global->global_context()); +} + + +Handle<Context> Isolate::GetCallingGlobalContext() { + JavaScriptFrameIterator it; +#ifdef ENABLE_DEBUGGER_SUPPORT + if (debug_->InDebugger()) { + while (!it.done()) { + JavaScriptFrame* frame = it.frame(); + Context* context = Context::cast(frame->context()); + if (context->global_context() == *debug_->debug_context()) { + it.Advance(); + } else { + break; + } + } + } +#endif // ENABLE_DEBUGGER_SUPPORT + if (it.done()) return Handle<Context>::null(); + JavaScriptFrame* frame = it.frame(); + Context* context = Context::cast(frame->context()); + return Handle<Context>(context->global_context()); +} + + +char* Isolate::ArchiveThread(char* to) { + if (RuntimeProfiler::IsEnabled() && current_vm_state() == JS) { + RuntimeProfiler::IsolateExitedJS(this); + } + memcpy(to, reinterpret_cast<char*>(thread_local_top()), + sizeof(ThreadLocalTop)); + InitializeThreadLocal(); + return to + sizeof(ThreadLocalTop); +} + + +char* Isolate::RestoreThread(char* from) { + memcpy(reinterpret_cast<char*>(thread_local_top()), from, + sizeof(ThreadLocalTop)); + // This might be just paranoia, but it seems to be needed in case a + // thread_local_ is restored on a separate OS thread. +#ifdef USE_SIMULATOR +#ifdef V8_TARGET_ARCH_ARM + thread_local_top()->simulator_ = Simulator::current(this); +#elif V8_TARGET_ARCH_MIPS + thread_local_top()->simulator_ = Simulator::current(this); +#endif +#endif + if (RuntimeProfiler::IsEnabled() && current_vm_state() == JS) { + RuntimeProfiler::IsolateEnteredJS(this); + } + return from + sizeof(ThreadLocalTop); +} + +} } // namespace v8::internal |