Introduce the SetFp function in StackHandler

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index 61792a628cd2cae82b87547dc9b17a0a02b17932..3f12cd21b26dd0a566cfe8ec51973cf33f9dac36 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -1521,9 +1521,10 @@ 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"
@@ -1542,9 +1543,10 @@ 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));
@@ -1560,7 +1562,7 @@ int StackHandler::Rewind(Isolate* isolate,
   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();