Add a level of indirection to exception handler addresses.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 14a04dc5dddb1180d7e99306eb9ed32455d6756d..5dcdf0bfe14c2f2038c9246c57a8d4f10bbec447 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -3829,6 +3829,9 @@ class Code: public HeapObject {
   DECL_ACCESSORS(relocation_info, ByteArray)
   void InvalidateRelocation();
 
+  // [handler_table]: Fixed array containing offsets of exception handlers.
+  DECL_ACCESSORS(handler_table, FixedArray)
+
   // [deoptimization_data]: Array containing data for deopt.
   DECL_ACCESSORS(deoptimization_data, FixedArray)
 
@@ -4057,8 +4060,9 @@ class Code: public HeapObject {
   // Layout description.
   static const int kInstructionSizeOffset = HeapObject::kHeaderSize;
   static const int kRelocationInfoOffset = kInstructionSizeOffset + kIntSize;
+  static const int kHandlerTableOffset = kRelocationInfoOffset + kPointerSize;

[Vyacheslav Egorov (Chromium), 2011/11/10 19:01:04]

I think this makes Code's header 64 bytes (with 28 bytes of padding) on ia32.

[Kevin Millikin (Chromium), 2011/11/11 11:22:50]

That's disappointing.  I guess we could later choose to move this into the
deoptimization data to save the padding at the cost of an extra indirection when
throwing.

   static const int kDeoptimizationDataOffset =
-      kRelocationInfoOffset + kPointerSize;
+      kHandlerTableOffset + kPointerSize;
   static const int kNextCodeFlushingCandidateOffset =
       kDeoptimizationDataOffset + kPointerSize;
   static const int kFlagsOffset =