[builtins] New frame type for exits to C++ builtins

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index 20776f6b1b37613ecfc1637b737677b500ccebe7..86aea896695c3475a9356f1b3b2fc3cad055ad4b 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -181,8 +181,8 @@ bool StackTraceFrameIterator::IsValidFrame(StackFrame* frame) const {
     return (script->IsScript() &&
             Script::TYPE_NATIVE != Script::cast(script)->type());
   }
-  // apart from javascript, only wasm is valid
-  return frame->is_wasm();
+  // apart from javascript, only wasm and builtin_exit are valid
+  return frame->is_wasm() || frame->is_builtin_exit();
 }
 
 
@@ -324,7 +324,7 @@ void SafeStackFrameIterator::Advance() {
       external_callback_scope_ = external_callback_scope_->previous();
     }
     if (frame_->is_java_script()) break;
-    if (frame_->is_exit()) {
+    if (frame_->is_exit() || frame_->is_builtin_exit()) {
       // Some of the EXIT frames may have ExternalCallbackScope allocated on
       // top of them. In that case the scope corresponds to the first EXIT
       // frame beneath it. There may be other EXIT frames on top of the
@@ -488,6 +488,7 @@ StackFrame::Type StackFrame::ComputeType(const StackFrameIteratorBase* iterator,
     case ENTRY:
     case ENTRY_CONSTRUCT:
     case EXIT:
+    case BUILTIN_EXIT:
     case STUB:
     case STUB_FAILURE_TRAMPOLINE:
     case INTERNAL:
@@ -561,7 +562,6 @@ Object*& ExitFrame::code_slot() const {
   return Memory::Object_at(fp() + offset);
 }
 
-
 Code* ExitFrame::unchecked_code() const {
   return reinterpret_cast<Code*>(code_slot());
 }
@@ -603,6 +603,26 @@ StackFrame::Type ExitFrame::GetStateForFramePointer(Address fp, State* state) {
   Address sp = ComputeStackPointer(fp);
   FillState(fp, sp, state);
   DCHECK(*state->pc_address != NULL);
+
+  return ComputeFrameType(fp);
+}
+
+StackFrame::Type ExitFrame::ComputeFrameType(Address fp) {
+  // Distinguish between between regular and builtin exit frames.
+  // Default to EXIT in all hairy cases (e.g., when called from profiler).
+  const int offset = CommonFrameConstants::kContextOrFrameTypeOffset;
+  Object* marker = Memory::Object_at(fp + offset);
+
+  if (!marker->IsSmi()) {
+    return EXIT;
+  }
+
+  StackFrame::Type frame_type =
+      static_cast<StackFrame::Type>(Smi::cast(marker)->value());
+  if (frame_type == EXIT || frame_type == BUILTIN_EXIT) {
+    return frame_type;
+  }
+
   return EXIT;
 }
 
@@ -625,6 +645,10 @@ void ExitFrame::FillState(Address fp, Address sp, State* state) {
   state->constant_pool_address = NULL;
 }
 
+JSFunction* BuiltinExitFrame::function() const {
+  return JSFunction::cast(function_slot_object());
+}
+
 Address StandardFrame::GetExpressionAddress(int n) const {
   const int offset = StandardFrameConstants::kExpressionsOffset;
   return fp() + offset - n * kPointerSize;
@@ -683,6 +707,7 @@ void StandardFrame::IterateCompiledFrame(ObjectVisitor* v) const {
       case ENTRY:
       case ENTRY_CONSTRUCT:
       case EXIT:
+      case BUILTIN_EXIT:
       case STUB_FAILURE_TRAMPOLINE:
       case ARGUMENTS_ADAPTOR:
       case STUB: