Rework the way we handle the fact that the ARM simulator uses a...

src/top.cc

 // 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
@@ skipping 13 matching lines @@
 // 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 "debug.h"
 #include "execution.h"
+#include "platform.h"
+#include "simulator.h"
 #include "string-stream.h"
-#include "platform.h"
 
 namespace v8 {
 namespace internal {
 
 ThreadLocalTop Top::thread_local_;
 Mutex* Top::break_access_ = OS::CreateMutex();
 
 NoAllocationStringAllocator* preallocated_message_space = NULL;
 
 Address top_addresses[] = {
 #define C(name) reinterpret_cast<Address>(Top::name()),
     TOP_ADDRESS_LIST(C)
     TOP_ADDRESS_LIST_PROF(C)
 #undef C
     NULL
 };
 
+
+v8::TryCatch* ThreadLocalTop::TryCatchHandler() {
+  return TRY_CATCH_FROM_ADDRESS(try_catch_handler_address());
+}
+
+
+void ThreadLocalTop::Initialize() {
+  c_entry_fp_ = 0;
+  handler_ = 0;
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  js_entry_sp_ = 0;
+#endif
+  stack_is_cooked_ = false;
+  try_catch_handler_address_ = NULL;
+  context_ = NULL;
+  int id = ThreadManager::CurrentId();
+  thread_id_ = (id == 0) ? ThreadManager::kInvalidId : id;
+  external_caught_exception_ = false;
+  failed_access_check_callback_ = NULL;
+  save_context_ = NULL;
+  catcher_ = NULL;
+}
+
+
 Address Top::get_address_from_id(Top::AddressId id) {
   return top_addresses[id];
 }
 
 
 char* Top::Iterate(ObjectVisitor* v, char* thread_storage) {
   ThreadLocalTop* thread = reinterpret_cast<ThreadLocalTop*>(thread_storage);
   Iterate(v, thread);
   return thread_storage + sizeof(ThreadLocalTop);
 }
 
 
 void Top::Iterate(ObjectVisitor* v, ThreadLocalTop* thread) {
   v->VisitPointer(&(thread->pending_exception_));
   v->VisitPointer(&(thread->pending_message_obj_));
   v->VisitPointer(
       bit_cast<Object**, Script**>(&(thread->pending_message_script_)));
   v->VisitPointer(bit_cast<Object**, Context**>(&(thread->context_)));
   v->VisitPointer(&(thread->scheduled_exception_));
 
-  for (v8::TryCatch* block = thread->try_catch_handler_;
+  for (v8::TryCatch* block = thread->TryCatchHandler();
        block != NULL;
-       block = block->next_) {
+       block = TRY_CATCH_FROM_ADDRESS(block->next_)) {
     v->VisitPointer(bit_cast<Object**, void**>(&(block->exception_)));
     v->VisitPointer(bit_cast<Object**, void**>(&(block->message_)));
   }
 
   // Iterate over pointers on native execution stack.
   for (StackFrameIterator it(thread); !it.done(); it.Advance()) {
     it.frame()->Iterate(v);
   }
 }
 
 
 void Top::Iterate(ObjectVisitor* v) {
   ThreadLocalTop* current_t = &thread_local_;
   Iterate(v, current_t);
 }
 
 
 void Top::InitializeThreadLocal() {
-  thread_local_.c_entry_fp_ = 0;
-  thread_local_.handler_ = 0;
-#ifdef ENABLE_LOGGING_AND_PROFILING
-  thread_local_.js_entry_sp_ = 0;
-#endif
-  thread_local_.stack_is_cooked_ = false;
-  thread_local_.try_catch_handler_ = NULL;
-  thread_local_.context_ = NULL;
-  int id = ThreadManager::CurrentId();
-  thread_local_.thread_id_ = (id == 0) ? ThreadManager::kInvalidId : id;
-  thread_local_.external_caught_exception_ = false;
-  thread_local_.failed_access_check_callback_ = NULL;
+  thread_local_.Initialize();
   clear_pending_exception();
   clear_pending_message();
   clear_scheduled_exception();
-  thread_local_.save_context_ = NULL;
-  thread_local_.catcher_ = NULL;
 }
 
 
 // Create a dummy thread that will wait forever on a semaphore. The only
 // purpose for this thread is to have some stack area to save essential data
 // into for use by a stacks only core dump (aka minidump).
 class PreallocatedMemoryThread: public Thread {
  public:
   PreallocatedMemoryThread() : keep_running_(true) {
     wait_for_ever_semaphore_ = OS::CreateSemaphore(0);
@@ skipping 126 matching lines @@
       delete preallocated_message_space;
       preallocated_message_space = NULL;
     }
 
     PreallocatedMemoryThread::StopThread();
     initialized = false;
   }
 }
 
 
-// There are cases where the C stack is separated from JS stack (ARM simulator).
-// To figure out the order of top-most JS try-catch handler and the top-most C
-// try-catch handler, the C try-catch handler keeps a reference to the top-most
-// JS try_catch handler when it was created.
-//
-// Here is a picture to explain the idea:
-//   Top::thread_local_.handler_       Top::thread_local_.try_catch_handler_
-//
-//             |                                         |
-//             v                                         v
-//
-//      | JS handler  |                        | C try_catch handler |
-//      |    next     |--+           +-------- |    js_handler_      |
-//                       |           |         |      next_          |--+
-//                       |           |                                  |
-//      | JS handler  |--+ <---------+                                  |
-//      |    next     |
-//
-// If the top-most JS try-catch handler is not equal to
-// Top::thread_local_.try_catch_handler_.js_handler_, it means the JS handler
-// is on the top. Otherwise, it means the C try-catch handler is on the top.
-//
 void Top::RegisterTryCatchHandler(v8::TryCatch* that) {
-  StackHandler* handler =
-    reinterpret_cast<StackHandler*>(thread_local_.handler_);
-
-  // Find the top-most try-catch handler.
-  while (handler != NULL && !handler->is_try_catch()) {
-    handler = handler->next();
-  }
-
-  that->js_handler_ = handler;  // casted to void*
-  thread_local_.try_catch_handler_ = 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_.set_try_catch_handler_address(address);
 }
 
 
 void Top::UnregisterTryCatchHandler(v8::TryCatch* that) {
-  ASSERT(thread_local_.try_catch_handler_ == that);
-  thread_local_.try_catch_handler_ = that->next_;
+  ASSERT(thread_local_.TryCatchHandler() == that);
+  thread_local_.set_try_catch_handler_address(
+      reinterpret_cast<Address>(that->next_));
   thread_local_.catcher_ = NULL;
+  SimulatorStack::UnregisterCTryCatch();
 }
 
 
 void Top::MarkCompactPrologue(bool is_compacting) {
   MarkCompactPrologue(is_compacting, &thread_local_);
 }
 
 
 void Top::MarkCompactPrologue(bool is_compacting, char* data) {
   MarkCompactPrologue(is_compacting, reinterpret_cast<ThreadLocalTop*>(data));
@@ skipping 411 matching lines @@
                                 bool catchable_by_javascript) {
   // Find the top-most try-catch handler.
   StackHandler* handler =
       StackHandler::FromAddress(Top::handler(Top::GetCurrentThread()));
   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.
-  v8::TryCatch* try_catch = thread_local_.try_catch_handler_;
+  Address external_handler_address = thread_local_.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.
-  //
-  // See comments in RegisterTryCatchHandler for details.
-  *is_caught_externally = try_catch != NULL &&
-      (handler == NULL || handler == try_catch->js_handler_ ||
+  *is_caught_externally = external_handler_address != NULL &&
+      (handler == NULL || handler->address() > external_handler_address ||
        !catchable_by_javascript);
 
   if (*is_caught_externally) {
     // Only report the exception if the external handler is verbose.
-    return thread_local_.try_catch_handler_->is_verbose_;
+    return thread_local_.TryCatchHandler()->is_verbose_;
   } else {
     // Report the exception if it isn't caught by JavaScript code.
     return handler == NULL;
   }
 }
 
 
 void Top::DoThrow(Object* exception,
                   MessageLocation* location,
                   const char* message) {
@@ skipping 16 matching lines @@
   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 =
       is_caught_externally &&
-      thread_local_.try_catch_handler_->capture_message_;
+      thread_local_.TryCatchHandler()->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.
@@ skipping 10 matching lines @@
   if (!message_obj.is_null()) {
     thread_local_.pending_message_obj_ = *message_obj;
     if (location != NULL) {
       thread_local_.pending_message_script_ = *location->script();
       thread_local_.pending_message_start_pos_ = location->start_pos();
       thread_local_.pending_message_end_pos_ = location->end_pos();
     }
   }
 
   if (is_caught_externally) {
-    thread_local_.catcher_ = thread_local_.try_catch_handler_;
+    thread_local_.catcher_ = thread_local_.TryCatchHandler();
   }
 
   // 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.
   set_pending_exception(*exception_handle);
 }
 
 
 void Top::ReportPendingMessages() {
   ASSERT(has_pending_exception());
   setup_external_caught();
   // 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 = thread_local_.external_caught_exception_;
   HandleScope scope;
   if (thread_local_.pending_exception_ == Failure::OutOfMemoryException()) {
     context()->mark_out_of_memory();
   } else if (thread_local_.pending_exception_ ==
              Heap::termination_exception()) {
     if (external_caught) {
-      thread_local_.try_catch_handler_->can_continue_ = false;
-      thread_local_.try_catch_handler_->exception_ = Heap::null_value();
+      thread_local_.TryCatchHandler()->can_continue_ = false;
+      thread_local_.TryCatchHandler()->exception_ = Heap::null_value();
     }
   } else {
     Handle<Object> exception(pending_exception());
     thread_local_.external_caught_exception_ = false;
     if (external_caught) {
-      thread_local_.try_catch_handler_->can_continue_ = true;
-      thread_local_.try_catch_handler_->exception_ =
+      thread_local_.TryCatchHandler()->can_continue_ = true;
+      thread_local_.TryCatchHandler()->exception_ =
         thread_local_.pending_exception_;
       if (!thread_local_.pending_message_obj_->IsTheHole()) {
         try_catch_handler()->message_ = thread_local_.pending_message_obj_;
       }
     }
     if (thread_local_.has_pending_message_) {
       thread_local_.has_pending_message_ = false;
       if (thread_local_.pending_message_ != NULL) {
         MessageHandler::ReportMessage(thread_local_.pending_message_);
       } else if (!thread_local_.pending_message_obj_->IsTheHole()) {
@@ skipping 33 matching lines @@
     if (is_termination_exception) {
       if (is_bottom_call) {
         thread_local_.external_caught_exception_ = false;
         clear_pending_exception();
         return false;
       }
     } else if (thread_local_.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_.try_catch_handler_ != NULL);
+      ASSERT(thread_local_.try_catch_handler_address() != NULL);
       Address external_handler_address =
-          reinterpret_cast<Address>(thread_local_.try_catch_handler_);
+          thread_local_.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_.external_caught_exception_ = false;
       clear_pending_exception();
@@ skipping 73 matching lines @@
   Top::break_access_->Lock();
 }
 
 
 ExecutionAccess::~ExecutionAccess() {
   Top::break_access_->Unlock();
 }
 
 
 } }  // namespace v8::internal