Check for empty repetitions.

src/regexp-macro-assembler-irregexp.cc

 // Copyright 2008 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 383 matching lines @@
                                                 int comparand,
                                                 Label* on_greater_or_equal) {
   ASSERT(comparand >= 0 && comparand <= 65535);
   Emit(BC_CHECK_REGISTER_GE);
   Emit(register_index);
   Emit16(comparand);
   EmitOrLink(on_greater_or_equal);
 }
 
 
+void RegExpMacroAssemblerIrregexp::IfRegisterEqPos(int register_index,
+                                                   Label* on_eq) {
+  Emit(BC_CHECK_REGISTER_EQ_POS);
+  Emit(register_index);
+  EmitOrLink(on_eq);
+}
+
+
 Handle<Object> RegExpMacroAssemblerIrregexp::GetCode(Handle<String> source) {
   Bind(&backtrack_);
   Emit(BC_POP_BT);
   Handle<ByteArray> array = Factory::NewByteArray(length());
   Copy(array->GetDataStartAddress());
   return array;
 }
 
 
 int RegExpMacroAssemblerIrregexp::length() {
@@ skipping 12 matching lines @@
   buffer_ = Vector<byte>::New(old_buffer.length() * 2);
   own_buffer_ = true;
   memcpy(buffer_.start(), old_buffer.start(), old_buffer.length());
   if (old_buffer_was_our_own) {
     old_buffer.Dispose();
   }
 }
 
 
 } }  // namespace v8::internal