8152207: Perform array bound checks while getting a length of bytecode instructions
authorasmotrak
Fri, 27 May 2016 09:25:49 -0700 (2016-05-27)
changeset 38724 233779eeb7f6
parent 38709 835ea8e8b295
child 38725 2a9e848a3276
8152207: Perform array bound checks while getting a length of bytecode instructions Reviewed-by: hseigel
hotspot/src/share/vm/interpreter/bytecodes.hpp
--- a/hotspot/src/share/vm/interpreter/bytecodes.hpp	Fri May 27 05:49:24 2016 -0700
+++ b/hotspot/src/share/vm/interpreter/bytecodes.hpp	Fri May 27 09:25:49 2016 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -386,15 +386,16 @@
   static Code       non_breakpoint_code_at(const Method* method, address bcp);
 
   // Bytecode attributes
-  static bool        is_defined     (int  code)    { return 0 <= code && code < number_of_codes && flags(code, false) != 0; }
+  static bool        is_valid       (int  code)    { return 0 <= code && code < number_of_codes; }
+  static bool        is_defined     (int  code)    { return is_valid(code) && flags(code, false) != 0; }
   static bool        wide_is_defined(int  code)    { return is_defined(code) && flags(code, true) != 0; }
   static const char* name           (Code code)    { check(code);      return _name          [code]; }
   static BasicType   result_type    (Code code)    { check(code);      return _result_type   [code]; }
   static int         depth          (Code code)    { check(code);      return _depth         [code]; }
   // Note: Length functions must return <=0 for invalid bytecodes.
   // Calling check(code) in length functions would throw an unwanted assert.
-  static int         length_for     (Code code)    { /*no check*/      return _lengths       [code] & 0xF; }
-  static int         wide_length_for(Code code)    { /*no check*/      return _lengths       [code] >> 4; }
+  static int         length_for     (Code code)    { return is_valid(code) ? _lengths[code] & 0xF : -1; }
+  static int         wide_length_for(Code code)    { return is_valid(code) ? _lengths[code]  >> 4 : -1; }
   static bool        can_trap       (Code code)    { check(code);      return has_all_flags(code, _bc_can_trap, false); }
   static Code        java_code      (Code code)    { check(code);      return _java_code     [code]; }
   static bool        can_rewrite    (Code code)    { check(code);      return has_all_flags(code, _bc_can_rewrite, false); }