* Irregexp: Handle backtrack past look-ahead.

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 86 matching lines @@
 
 
 void RegExpMacroAssemblerIrregexp::WriteCurrentPositionToRegister(
     int register_index, int cp_offset) {
   ASSERT(register_index >= 0);
   Emit(BC_SET_REGISTER_TO_CP, register_index);
   Emit32(cp_offset);  // Current position offset.
 }
 
 
-void RegExpMacroAssemblerIrregexp::ClearRegister(int reg) {
-  SetRegister(reg, -1);
+void RegExpMacroAssemblerIrregexp::ClearRegisters(int reg_from, int reg_to) {
+  ASSERT(reg_from <= reg_to);
+  for (int reg = reg_from; reg <= reg_to; reg++) {
+    SetRegister(reg, -1);
+  }
 }
 
 
 void RegExpMacroAssemblerIrregexp::ReadCurrentPositionFromRegister(
     int register_index) {
   ASSERT(register_index >= 0);
   Emit(BC_SET_CP_TO_REGISTER, register_index);
 }
 
 
@@ skipping 321 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