[builtins] support exception handling in TFJ builtins

src/frames.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/frames.h"
 
 #include <memory>
 #include <sstream>
 
 #include "src/ast/ast.h"
@@ skipping 861 matching lines @@
 
 void StubFrame::Iterate(ObjectVisitor* v) const {
   IterateCompiledFrame(v);
 }
 
 
 Code* StubFrame::unchecked_code() const {
   return static_cast<Code*>(isolate()->FindCodeObject(pc()));
 }
 
+int StubFrame::LookupExceptionHandlerInTable(

[caitp, 2016/08/19 14:30:09]

seems to be unnecessary, only seemed to come up due to the tests generating stub
code rather than JS frames.

+    int* stack_slots, HandlerTable::CatchPrediction* prediction) {
+  DCHECK_NULL(prediction);
+  Code* code = LookupCode();
+
+  // Only support catch handlers in TFJ builtins.
+  if (!code->is_turbofanned()) return -1;
+  if (code->kind() != Code::BUILTIN) return -1;
+
+  HandlerTable* table = HandlerTable::cast(code->handler_table());
+  int pc_offset = static_cast<int>(pc() - code->entry());
+  if (stack_slots) *stack_slots = code->stack_slots();
+  return table->LookupReturn(pc_offset);
+}
 
 Address StubFrame::GetCallerStackPointer() const {
   return fp() + ExitFrameConstants::kCallerSPOffset;
 }
 
 
 int StubFrame::GetNumberOfIncomingArguments() const {
   return 0;
 }
 
@@ skipping 1018 matching lines @@
   for (StackFrameIterator it(isolate); !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
     list.Add(frame, zone);
   }
   return list.ToVector();
 }
 
 
 }  // namespace internal
 }  // namespace v8