Move some isolate state setup from C++ code to JumpToExceptionHandler stub

runtime/vm/exceptions.cc

 // 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 "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
 #include "vm/flags.h"
@@ skipping 262 matching lines @@
                                    uword stack_pointer,
                                    uword frame_pointer,
                                    const Object& exception_object,
                                    const Object& stacktrace_object) {
   // The no_gc StackResource is unwound through the tear down of
   // stack resources below.
   NoGCScope no_gc;
   RawObject* raw_exception = exception_object.raw();
   RawObject* raw_stacktrace = stacktrace_object.raw();
 
-  // The following three operations are part of the 'epilogue' of the
-  // CallToRuntime, CallBootstrapCFunction, and CallNativeCFunction stubs.
-  // In the case of an exception, we skip the epilogues and must set the
-  // correct state here.
-  isolate->set_vm_tag(VMTag::kScriptTagId);
-  isolate->set_top_exit_frame_info(0);
+  // The following operation is part of the 'epilogue' of the CallToRuntime,
+  // CallBootstrapCFunction, and CallNativeCFunction stubs. In the case of an
+  // exception, we skip the epilogues and must set the correct state here.
+  // The other operations performed as part of the 'epilogue' are handled
+  // by the simulator's Longjmp or the JumpToExceptionHandler stub.
   isolate->set_top_context(Context::null());
 
 #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()->Longjmp(program_counter, stack_pointer, frame_pointer,
-                                raw_exception, raw_stacktrace);
+                                raw_exception, raw_stacktrace, isolate);
 #else
   // Prepare for unwinding frames by destroying all the stack resources
   // in the previous frames.
 
   while (isolate->top_resource() != NULL &&
          (reinterpret_cast<uword>(isolate->top_resource()) < stack_pointer)) {
     isolate->top_resource()->~StackResource();
   }
 
   // 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, RawObject*, RawObject*);
+  typedef void (*ExcpHandler)(uword, uword, uword, RawObject*, RawObject*,
+                              Isolate*);
   ExcpHandler func = reinterpret_cast<ExcpHandler>(
       StubCode::JumpToExceptionHandlerEntryPoint());
 
   // Unpoison the stack before we tear it down in the generated stub code.
   uword current_sp = reinterpret_cast<uword>(&program_counter) - 1024;
   __asan_unpoison_memory_region(reinterpret_cast<void*>(current_sp),
                                 stack_pointer - current_sp);
 
   func(program_counter, stack_pointer, frame_pointer,
-       raw_exception, raw_stacktrace);
+       raw_exception, raw_stacktrace, isolate);
 #endif
   UNREACHABLE();
 }
 
 
 static RawField* LookupStacktraceField(const Instance& instance) {
   if (instance.GetClassId() < kNumPredefinedCids) {
     // 'class Error' is not a predefined class.
     return Field::null();
   }
@@ skipping 423 matching lines @@
 
 // Throw JavascriptCompatibilityError exception.
 void Exceptions::ThrowJavascriptCompatibilityError(const char* msg) {
   const Array& exc_args = Array::Handle(Array::New(1));
   const String& msg_str = String::Handle(String::New(msg));
   exc_args.SetAt(0, msg_str);
   Exceptions::ThrowByType(Exceptions::kJavascriptCompatibilityError, exc_args);
 }
 
 }  // namespace dart