Introduce the SetFp function in StackHandler

src/frames.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1503 matching lines @@
 }
 
 
 // -------------------------------------------------------------------------
 
 
 void StackHandler::Unwind(Isolate* isolate,
                           FixedArray* array,
                           int offset,
                           int previous_handler_offset) const {
-  STATIC_ASSERT(StackHandlerConstants::kSlotCount == 5);
+  STATIC_ASSERT(StackHandlerConstants::kSlotCount == 5 ||
+                StackHandlerConstants::kSlotCount == 6);

[danno, 2013/07/24 13:28:57]

I think this assert needs to be:

STATIC_ASSERT(StackHandlerConstants::kSlotCount >= 5)

because I think the reason is to ensure that the array indices used below will
all be valid, but as long as there are 5 or more slots, everything is OK.

[haitao.feng, 2013/07/24 13:44:17]

Done.

[haitao.feng, 2013/07/24 13:44:17]

Done.

   ASSERT_LE(0, offset);
-  ASSERT_GE(array->length(), offset + 5);
+  ASSERT_GE(array->length(), offset + StackHandlerConstants::kSlotCount);
   // Unwinding a stack handler into an array chains it in the opposite
   // direction, re-using the "next" slot as a "previous" link, so that stack
   // handlers can be later re-wound in the correct order.  Decode the "state"
   // slot into "index" and "kind" and store them separately, using the fp slot.
   array->set(offset, Smi::FromInt(previous_handler_offset));        // next
   array->set(offset + 1, *code_address());                          // code
   array->set(offset + 2, Smi::FromInt(static_cast<int>(index())));  // state
   array->set(offset + 3, *context_address());                       // context
   array->set(offset + 4, Smi::FromInt(static_cast<int>(kind())));   // fp
 
   *isolate->handler_address() = next()->address();
 }
 
 
 int StackHandler::Rewind(Isolate* isolate,
                          FixedArray* array,
                          int offset,
                          Address fp) {
-  STATIC_ASSERT(StackHandlerConstants::kSlotCount == 5);
+  STATIC_ASSERT(StackHandlerConstants::kSlotCount == 5 ||
+                StackHandlerConstants::kSlotCount == 6);

[danno, 2013/07/24 13:28:57]

See comment above

[haitao.feng, 2013/07/24 13:44:17]

Done.

   ASSERT_LE(0, offset);
-  ASSERT_GE(array->length(), offset + 5);
+  ASSERT_GE(array->length(), offset + StackHandlerConstants::kSlotCount);
   Smi* prev_handler_offset = Smi::cast(array->get(offset));
   Code* code = Code::cast(array->get(offset + 1));
   Smi* smi_index = Smi::cast(array->get(offset + 2));
   Object* context = array->get(offset + 3);
   Smi* smi_kind = Smi::cast(array->get(offset + 4));
 
   unsigned state = KindField::encode(static_cast<Kind>(smi_kind->value())) |
       IndexField::encode(static_cast<unsigned>(smi_index->value()));
 
   Memory::Address_at(address() + StackHandlerConstants::kNextOffset) =
       *isolate->handler_address();
   Memory::Object_at(address() + StackHandlerConstants::kCodeOffset) = code;
   Memory::uintptr_at(address() + StackHandlerConstants::kStateOffset) = state;
   Memory::Object_at(address() + StackHandlerConstants::kContextOffset) =
       context;
-  Memory::Address_at(address() + StackHandlerConstants::kFPOffset) = fp;
+  SetFp(address() + StackHandlerConstants::kFPOffset, fp);
 
   *isolate->handler_address() = address();
 
   return prev_handler_offset->value();
 }
 
 
 // -------------------------------------------------------------------------
 
 int NumRegs(RegList reglist) {
@@ skipping 54 matching lines @@
   ZoneList<StackFrame*> list(10, zone);
   for (StackFrameIterator it(isolate); !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
     list.Add(frame, zone);
   }
   return list.ToVector();
 }
 
 
 } }  // namespace v8::internal