jdk8-mips64-public/hotspot: src/share/vm/interpreter/bytecodeStream.hpp@8012aa3ccede

4926272: methodOopDesc::method_from_bcp is unsafe
Reviewed-by: coleenp, jrose, kvn, dcubed

     1 /*

     2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

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    23  */

    25 #ifndef SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP

    26 #define SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP

    28 #include "interpreter/bytecode.hpp"

    29 #include "memory/allocation.hpp"

    30 #include "oops/methodOop.hpp"

    31 #ifdef TARGET_ARCH_x86

    32 # include "bytes_x86.hpp"

    33 #endif

    34 #ifdef TARGET_ARCH_sparc

    35 # include "bytes_sparc.hpp"

    36 #endif

    37 #ifdef TARGET_ARCH_zero

    38 # include "bytes_zero.hpp"

    39 #endif

    41 // A BytecodeStream is used for fast iteration over the bytecodes

    42 // of a methodOop.

    43 //

    44 // Usage:

    45 //

    46 // BytecodeStream s(method);

    47 // Bytecodes::Code c;

    48 // while ((c = s.next()) >= 0) {

    49 //   ...

    50 // }

    52 // A RawBytecodeStream is a simple version of BytecodeStream.

    53 // It is used ONLY when we know the bytecodes haven't been rewritten

    54 // yet, such as in the rewriter or the verifier.

    56 // Here is the common base class for both RawBytecodeStream and BytecodeStream:

    57 class BaseBytecodeStream: StackObj {

    58  protected:

    59   // stream buffer

    60   methodHandle    _method;                       // read from method directly

    62   // reading position

    63   int             _bci;                          // bci if current bytecode

    64   int             _next_bci;                     // bci of next bytecode

    65   int             _end_bci;                      // bci after the current iteration interval

    67   // last bytecode read

    68   Bytecodes::Code _raw_code;

    69   bool            _is_wide;

    70   bool            _is_raw;                       // false in 'cooked' BytecodeStream

    72   // Construction

    73   BaseBytecodeStream(methodHandle method) : _method(method) {

    74     set_interval(0, _method->code_size());

    75     _is_raw = false;

    76   }

    78  public:

    79   // Iteration control

    80   void set_interval(int beg_bci, int end_bci) {

    81     // iterate over the interval [beg_bci, end_bci)

    82     assert(0 <= beg_bci && beg_bci <= method()->code_size(), "illegal beg_bci");

    83     assert(0 <= end_bci && end_bci <= method()->code_size(), "illegal end_bci");

    84     // setup of iteration pointers

    85     _bci      = beg_bci;

    86     _next_bci = beg_bci;

    87     _end_bci  = end_bci;

    88   }

    89   void set_start   (int beg_bci) {

    90     set_interval(beg_bci, _method->code_size());

    91   }

    93   bool is_raw() const { return _is_raw; }

    95   // Stream attributes

    96   methodHandle    method() const                 { return _method; }

    98   int             bci() const                    { return _bci; }

    99   int             next_bci() const               { return _next_bci; }

   100   int             end_bci() const                { return _end_bci; }

   102   Bytecodes::Code raw_code() const               { return _raw_code; }

   103   bool            is_wide() const                { return _is_wide; }

   104   int             instruction_size() const       { return (_next_bci - _bci); }

   105   bool            is_last_bytecode() const       { return _next_bci >= _end_bci; }

   107   address         bcp() const                    { return method()->code_base() + _bci; }

   108   Bytecode        bytecode() const               { return Bytecode(_method(), bcp()); }

   110   // State changes

   111   void            set_next_bci(int bci)          { assert(0 <= bci && bci <= method()->code_size(), "illegal bci"); _next_bci = bci; }

   113   // Bytecode-specific attributes

   114   int             dest() const                   { return bci() + bytecode().get_offset_s2(raw_code()); }

   115   int             dest_w() const                 { return bci() + bytecode().get_offset_s4(raw_code()); }

   117   // One-byte indices.

   118   int             get_index_u1() const           { assert_raw_index_size(1); return *(jubyte*)(bcp()+1); }

   120  protected:

   121   void assert_raw_index_size(int size) const NOT_DEBUG_RETURN;

   122   void assert_raw_stream(bool want_raw) const NOT_DEBUG_RETURN;

   123 };

   125 class RawBytecodeStream: public BaseBytecodeStream {

   126  public:

   127   // Construction

   128   RawBytecodeStream(methodHandle method) : BaseBytecodeStream(method) {

   129     _is_raw = true;

   130   }

   132  public:

   133   // Iteration

   134   // Use raw_next() rather than next() for faster method reference

   135   Bytecodes::Code raw_next() {

   136     Bytecodes::Code code;

   137     // set reading position

   138     _bci = _next_bci;

   139     assert(!is_last_bytecode(), "caller should check is_last_bytecode()");

   141     address bcp = this->bcp();

   142     code        = Bytecodes::code_or_bp_at(bcp);

   144     // set next bytecode position

   145     int l = Bytecodes::length_for(code);

   146     if (l > 0 && (_bci + l) <= _end_bci) {

   147       assert(code != Bytecodes::_wide && code != Bytecodes::_tableswitch

   148              && code != Bytecodes::_lookupswitch, "can't be special bytecode");

   149       _is_wide = false;

   150       _next_bci += l;

   151       _raw_code = code;

   152       return code;

   153     } else {

   154       return raw_next_special(code);

   155     }

   156   }

   157   Bytecodes::Code raw_next_special(Bytecodes::Code code);

   159   // Unsigned indices, widening, with no swapping of bytes

   160   int             get_index() const          { return (is_wide()) ? get_index_u2_raw(bcp() + 2) : get_index_u1(); }

   161   // Get an unsigned 2-byte index, with no swapping of bytes.

   162   int             get_index_u2() const       { assert(!is_wide(), ""); return get_index_u2_raw(bcp() + 1);  }

   164  private:

   165   int get_index_u2_raw(address p) const {

   166     assert_raw_index_size(2); assert_raw_stream(true);

   167     return Bytes::get_Java_u2(p);

   168   }

   169 };

   171 // In BytecodeStream, non-java bytecodes will be translated into the

   172 // corresponding java bytecodes.

   174 class BytecodeStream: public BaseBytecodeStream {

   175   Bytecodes::Code _code;

   177  public:

   178   // Construction

   179   BytecodeStream(methodHandle method) : BaseBytecodeStream(method) { }

   181   // Iteration

   182   Bytecodes::Code next() {

   183     Bytecodes::Code raw_code, code;

   184     // set reading position

   185     _bci = _next_bci;

   186     if (is_last_bytecode()) {

   187       // indicate end of bytecode stream

   188       raw_code = code = Bytecodes::_illegal;

   189     } else {

   190       // get bytecode

   191       address bcp = this->bcp();

   192       raw_code = Bytecodes::code_at(_method(), bcp);

   193       code = Bytecodes::java_code(raw_code);

   194       // set next bytecode position

   195       //

   196       // note that we cannot advance before having the

   197       // tty bytecode otherwise the stepping is wrong!

   198       // (carefull: length_for(...) must be used first!)

   199       int l = Bytecodes::length_for(code);

   200       if (l == 0) l = Bytecodes::length_at(_method(), bcp);

   201       _next_bci  += l;

   202       assert(_bci < _next_bci, "length must be > 0");

   203       // set attributes

   204       _is_wide      = false;

   205       // check for special (uncommon) cases

   206       if (code == Bytecodes::_wide) {

   207         raw_code = (Bytecodes::Code)bcp[1];

   208         code = raw_code;  // wide BCs are always Java-normal

   209         _is_wide = true;

   210       }

   211       assert(Bytecodes::is_java_code(code), "sanity check");

   212     }

   213     _raw_code = raw_code;

   214     _code = code;

   215     return _code;

   216   }

   218   bool            is_active_breakpoint() const   { return Bytecodes::is_active_breakpoint_at(bcp()); }

   219   Bytecodes::Code code() const                   { return _code; }

   221   // Unsigned indices, widening

   222   int             get_index() const              { return is_wide() ? bytecode().get_index_u2(raw_code(), true) : get_index_u1(); }

   223   // Get an unsigned 2-byte index, swapping the bytes if necessary.

   224   int             get_index_u2() const           { assert_raw_stream(false);

   225                                                    return bytecode().get_index_u2(raw_code(), false); }

   226   // Get an unsigned 2-byte index in native order.

   227   int             get_index_u2_cpcache() const   { assert_raw_stream(false);

   228                                                    return bytecode().get_index_u2_cpcache(raw_code()); }

   229   int             get_index_u4() const           { assert_raw_stream(false);

   230                                                    return bytecode().get_index_u4(raw_code()); }

   231   bool            has_index_u4() const           { return bytecode().has_index_u4(raw_code()); }

   232 };

   234 #endif // SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/interpreter/bytecodeStream.hpp@8012aa3ccede

src/share/vm/interpreter/bytecodeStream.hpp