Change the handling of the debug break stack guard

src/ia32/regexp-macro-assembler-ia32.cc

 // Copyright 2008-2009 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 1177 matching lines @@
 
   // The original start address of the characters to match.
   const byte* start_address = frame_entry<const byte*>(re_frame, kInputStart);
 
   // Find the current start address of the same character at the current string
   // position.
   int start_index = frame_entry<int>(re_frame, kStartIndex);
   const byte* new_address = StringCharacterPosition(*subject, start_index);
 
   if (start_address != new_address) {
-    // If there is a difference, update start and end addresses in the
-    // RegExp stack frame to match the new value.
+    // If there is a difference, update the object pointer and start and end
+    // addresses in the RegExp stack frame to match the new value.
     const byte* end_address = frame_entry<const byte* >(re_frame, kInputEnd);
     int byte_length = end_address - start_address;
+    frame_entry<const String*>(re_frame, kInputString) = *subject;
     frame_entry<const byte*>(re_frame, kInputStart) = new_address;
     frame_entry<const byte*>(re_frame, kInputEnd) = new_address + byte_length;
   }
 
   return 0;
 }
 
 
 Address RegExpMacroAssemblerIA32::GrowStack(Address stack_pointer,
                                             Address* stack_top) {
@@ skipping 170 matching lines @@
 
 
 void RegExpMacroAssemblerIA32::LoadConstantBufferAddress(Register reg,
                                                          ArraySlice* buffer) {
   __ mov(reg, buffer->array());
   __ add(Operand(reg), Immediate(buffer->base_offset()));
 }
 
 #undef __
 }}  // namespace v8::internal