stackMapTable.hpp 6.1 KB
Newer Older
D
duke 已提交
1
/*
2
 * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
D
duke 已提交
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
19 20 21
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
D
duke 已提交
22 23 24
 *
 */

25 26 27 28
#ifndef SHARE_VM_CLASSFILE_STACKMAPTABLE_HPP
#define SHARE_VM_CLASSFILE_STACKMAPTABLE_HPP

#include "classfile/stackMapFrame.hpp"
29
#include "classfile/verifier.hpp"
30
#include "memory/allocation.hpp"
31 32
#include "oops/constantPool.hpp"
#include "oops/method.hpp"
33 34 35 36 37 38 39 40 41 42
#include "utilities/globalDefinitions.hpp"
#ifdef TARGET_ARCH_x86
# include "bytes_x86.hpp"
#endif
#ifdef TARGET_ARCH_sparc
# include "bytes_sparc.hpp"
#endif
#ifdef TARGET_ARCH_zero
# include "bytes_zero.hpp"
#endif
43 44 45 46 47 48
#ifdef TARGET_ARCH_arm
# include "bytes_arm.hpp"
#endif
#ifdef TARGET_ARCH_ppc
# include "bytes_ppc.hpp"
#endif
49

D
duke 已提交
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76
class StackMapReader;

// StackMapTable class is the StackMap table used by type checker
class StackMapTable : public StackObj {
 private:
  // Logically, the _frame_count (as well as many fields in the StackFrame)
  // should be a u2, but if we defined the variable as that type it will
  // be difficult to detect/recover from overflow or underflow conditions.
  // Widening the type and making it signed will help detect these.
  int32_t              _code_length;
  int32_t              _frame_count;     // Stackmap frame count
  StackMapFrame**       _frame_array;

 public:
  StackMapTable(StackMapReader* reader, StackMapFrame* init_frame,
                u2 max_locals, u2 max_stack,
                char* code_data, int code_len, TRAPS);

  inline int32_t get_frame_count() const { return _frame_count; }
  inline int get_offset(int index) const {
    return _frame_array[index]->offset();
  }

  // Match and/or update current_frame to the frame in stackmap table with
  // specified offset. Return true if the two frames match.
  bool match_stackmap(
    StackMapFrame* current_frame, int32_t offset,
77
    bool match, bool update, ErrorContext* ctx, TRAPS) const;
D
duke 已提交
78 79 80 81
  // Match and/or update current_frame to the frame in stackmap table with
  // specified offset and frame index. Return true if the two frames match.
  bool match_stackmap(
    StackMapFrame* current_frame, int32_t offset, int32_t frame_index,
82
    bool match, bool update, ErrorContext* ctx, TRAPS) const;
D
duke 已提交
83 84 85 86 87 88 89 90 91 92

  // Check jump instructions. Make sure there are no uninitialized
  // instances on backward branch.
  void check_jump_target(StackMapFrame* frame, int32_t target, TRAPS) const;

  // The following methods are only used inside this class.

  // Returns the frame array index where the frame with offset is stored.
  int get_index_from_offset(int32_t offset) const;

93
  void print_on(outputStream* str) const;
D
duke 已提交
94 95 96 97
};

class StackMapStream : StackObj {
 private:
98
  Array<u1>* _data;
D
duke 已提交
99 100
  int _index;
 public:
101
  StackMapStream(Array<u1>* ah)
D
duke 已提交
102 103 104 105 106 107
    : _data(ah), _index(0) {
  }
  u1 get_u1(TRAPS) {
    if (_data == NULL || _index >= _data->length()) {
      stackmap_format_error("access beyond the end of attribute", CHECK_0);
    }
108
    return _data->at(_index++);
D
duke 已提交
109 110 111 112 113
  }
  u2 get_u2(TRAPS) {
    if (_data == NULL || _index >= _data->length() - 1) {
      stackmap_format_error("access beyond the end of attribute", CHECK_0);
    }
114
    u2 res = Bytes::get_Java_u2(_data->adr_at(_index));
D
duke 已提交
115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181
    _index += 2;
    return res;
  }
  bool at_end() {
    return (_data == NULL) || (_index == _data->length());
  }
  static void stackmap_format_error(const char* msg, TRAPS);
};

class StackMapReader : StackObj {
 private:
  // information about the class and method
  constantPoolHandle  _cp;
  ClassVerifier* _verifier;
  StackMapStream* _stream;
  char* _code_data;
  int32_t _code_length;

  // information get from the attribute
  int32_t  _frame_count;       // frame count

  int32_t chop(VerificationType* locals, int32_t length, int32_t chops);
  VerificationType parse_verification_type(u1* flags, TRAPS);
  void check_verification_type_array_size(
      int32_t size, int32_t max_size, TRAPS) {
    if (size < 0 || size > max_size) {
      // Since this error could be caused someone rewriting the method
      // but not knowing to update the stackmap data, we call the the
      // verifier's error method, which may not throw an exception and
      // failover to the old verifier instead.
      _verifier->class_format_error(
        "StackMapTable format error: bad type array size");
    }
  }

  enum {
    SAME_LOCALS_1_STACK_ITEM_EXTENDED = 247,
    SAME_EXTENDED = 251,
    FULL = 255
  };

 public:
  // Constructor
  StackMapReader(ClassVerifier* v, StackMapStream* stream, char* code_data,
                 int32_t code_len, TRAPS) :
                 _verifier(v), _stream(stream),
                 _code_data(code_data), _code_length(code_len) {
    methodHandle m = v->method();
    if (m->has_stackmap_table()) {
      _cp = constantPoolHandle(THREAD, m->constants());
      _frame_count = _stream->get_u2(CHECK);
    } else {
      // There's no stackmap table present. Frame count and size are 0.
      _frame_count = 0;
    }
  }

  inline int32_t get_frame_count() const                { return _frame_count; }
  StackMapFrame* next(StackMapFrame* pre_frame, bool first,
                      u2 max_locals, u2 max_stack, TRAPS);

  void check_end(TRAPS) {
    if (!_stream->at_end()) {
      StackMapStream::stackmap_format_error("wrong attribute size", CHECK);
    }
  }
};
182 183

#endif // SHARE_VM_CLASSFILE_STACKMAPTABLE_HPP