Move FormatStackTrace to C++

src/isolate.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 414 matching lines @@
   Isolate* isolate_;
 
   const FrameSkipMode mode_;
   const Handle<Object> caller_;
   bool skip_next_frame_;
 
   int sloppy_frames_;
   bool encountered_strict_function_;
 };
 
+namespace {
+
+// TODO(jgruber): Fix all cases in which frames give us a hole value (e.g. the
+// receiver in RegExp constructor frames.
+Handle<Object> HoleToUndefined(Isolate* isolate, Handle<Object> in) {

[Yang, 2016/08/01 06:49:18]

Let's call this TheHoleToUndefined.

[jgruber, 2016/08/01 10:52:55]

Done.

+  return (in->IsTheHole(isolate))
+             ? Handle<Object>::cast(isolate->factory()->undefined_value())
+             : in;
+}
+}
+
 Handle<Object> Isolate::CaptureSimpleStackTrace(Handle<JSReceiver> error_object,
                                                 FrameSkipMode mode,
                                                 Handle<Object> caller) {
   DisallowJavascriptExecution no_js(this);
 
   // Get stack trace limit.
   Handle<JSObject> error = error_function();
   Handle<String> stackTraceLimit =
       factory()->InternalizeUtf8String("stackTraceLimit");
   DCHECK(!stackTraceLimit.is_null());
@@ skipping 39 matching lines @@
             // Help CallSite::IsConstructor correctly detect hand-written
             // construct stubs.
             Code* code = Code::cast(*abstract_code);
             if (code->is_construct_stub()) {
               recv = handle(heap()->call_site_constructor_symbol(), this);
             }
           }
           Handle<Smi> offset(Smi::FromInt(frames[i].code_offset()), this);
 
           elements = MaybeGrow(this, elements, cursor, cursor + 4);
-          elements->set(cursor++, *recv);
+          elements->set(cursor++, *HoleToUndefined(this, recv));
           elements->set(cursor++, *fun);
           elements->set(cursor++, *abstract_code);
           elements->set(cursor++, *offset);
           frames_seen++;
         }
       } break;
 
       case StackFrame::BUILTIN_EXIT: {
         BuiltinExitFrame* exit_frame = BuiltinExitFrame::cast(frame);
         Handle<JSFunction> fun = handle(exit_frame->function(), this);
@@ skipping 2662 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8