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

runtime/vm/profiler.cc

Index: runtime/vm/profiler.cc
diff --git a/runtime/vm/profiler.cc b/runtime/vm/profiler.cc
index c4fe878ba9d7d2216b055b5fa0006118bbe603cf..8bc24207c6e74a97eb79ae10217f43249d8beed8 100644
--- a/runtime/vm/profiler.cc
+++ b/runtime/vm/profiler.cc
@@ -1869,6 +1869,12 @@ void Profiler::RecordSampleInterruptCallback(
   if (sample_buffer == NULL) {
     return;
   }
+  if (StubCode::InJumpToExceptionHandlerStub(state.pc)) {
+    // The JumpToExceptionHandler stub manually adjusts the stack pointer,
+    // frame pointer, and some isolate state before jumping to a catch entry.
+    // It is not safe to walk the stack when executing this stub.
+    return;
+  }

[siva, 2014/07/16 17:54:09]

Maybe move this bail out further up.

   Sample* sample = sample_buffer->ReserveSample();
   sample->Init(isolate, OS::GetCurrentTimeMicros(), state.tid);
   sample->set_vm_tag(isolate->vm_tag());
@@ -1890,8 +1896,9 @@ void Profiler::RecordSampleInterruptCallback(
     stackWalker.walk(isolate->heap());
   } else {
     if ((isolate->stub_code() != NULL) &&
-        (isolate->top_exit_frame_info() != 0)) {
-      // Collect only Dart frames.
+        (isolate->top_exit_frame_info() != 0) &&
+        (isolate->vm_tag() != VMTag::kScriptTagId)) {
+      // We have a valid exit frame info, use the Dart stack walker.
       ProfilerDartStackWalker stackWalker(isolate, sample);
       stackWalker.walk();
     } else {