Thu, 19 Mar 2009 09:13:24 -0700
Merge
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | // A BytecodeStream is used for fast iteration over the bytecodes |
duke@435 | 26 | // of a methodOop. |
duke@435 | 27 | // |
duke@435 | 28 | // Usage: |
duke@435 | 29 | // |
duke@435 | 30 | // BytecodeStream s(method); |
duke@435 | 31 | // Bytecodes::Code c; |
duke@435 | 32 | // while ((c = s.next()) >= 0) { |
duke@435 | 33 | // ... |
duke@435 | 34 | // } |
duke@435 | 35 | // |
duke@435 | 36 | // A RawBytecodeStream is a simple version of BytecodeStream. |
duke@435 | 37 | // It is used ONLY when we know the bytecodes haven't been rewritten |
duke@435 | 38 | // yet, such as in the rewriter or the verifier. Currently only the |
duke@435 | 39 | // verifier uses this class. |
duke@435 | 40 | |
duke@435 | 41 | class RawBytecodeStream: StackObj { |
duke@435 | 42 | protected: |
duke@435 | 43 | // stream buffer |
duke@435 | 44 | methodHandle _method; // read from method directly |
duke@435 | 45 | |
duke@435 | 46 | // reading position |
duke@435 | 47 | int _bci; // bci if current bytecode |
duke@435 | 48 | int _next_bci; // bci of next bytecode |
duke@435 | 49 | int _end_bci; // bci after the current iteration interval |
duke@435 | 50 | |
duke@435 | 51 | // last bytecode read |
duke@435 | 52 | Bytecodes::Code _code; |
duke@435 | 53 | bool _is_wide; |
duke@435 | 54 | |
duke@435 | 55 | public: |
duke@435 | 56 | // Construction |
duke@435 | 57 | RawBytecodeStream(methodHandle method) : _method(method) { |
duke@435 | 58 | set_interval(0, _method->code_size()); |
duke@435 | 59 | } |
duke@435 | 60 | |
duke@435 | 61 | // Iteration control |
duke@435 | 62 | void set_interval(int beg_bci, int end_bci) { |
duke@435 | 63 | // iterate over the interval [beg_bci, end_bci) |
duke@435 | 64 | assert(0 <= beg_bci && beg_bci <= method()->code_size(), "illegal beg_bci"); |
duke@435 | 65 | assert(0 <= end_bci && end_bci <= method()->code_size(), "illegal end_bci"); |
duke@435 | 66 | // setup of iteration pointers |
duke@435 | 67 | _bci = beg_bci; |
duke@435 | 68 | _next_bci = beg_bci; |
duke@435 | 69 | _end_bci = end_bci; |
duke@435 | 70 | } |
duke@435 | 71 | void set_start (int beg_bci) { |
duke@435 | 72 | set_interval(beg_bci, _method->code_size()); |
duke@435 | 73 | } |
duke@435 | 74 | |
duke@435 | 75 | // Iteration |
duke@435 | 76 | // Use raw_next() rather than next() for faster method reference |
duke@435 | 77 | Bytecodes::Code raw_next() { |
duke@435 | 78 | Bytecodes::Code code; |
duke@435 | 79 | // set reading position |
duke@435 | 80 | _bci = _next_bci; |
duke@435 | 81 | assert(!is_last_bytecode(), "caller should check is_last_bytecode()"); |
duke@435 | 82 | |
duke@435 | 83 | address bcp = RawBytecodeStream::bcp(); |
duke@435 | 84 | code = Bytecodes::code_or_bp_at(bcp); |
duke@435 | 85 | |
duke@435 | 86 | // set next bytecode position |
duke@435 | 87 | int l = Bytecodes::length_for(code); |
duke@435 | 88 | if (l > 0 && (_bci + l) <= _end_bci) { |
duke@435 | 89 | assert(code != Bytecodes::_wide && code != Bytecodes::_tableswitch |
duke@435 | 90 | && code != Bytecodes::_lookupswitch, "can't be special bytecode"); |
duke@435 | 91 | _is_wide = false; |
duke@435 | 92 | _next_bci += l; |
duke@435 | 93 | _code = code; |
duke@435 | 94 | return code; |
duke@435 | 95 | } else if (code == Bytecodes::_wide && _bci + 1 >= _end_bci) { |
duke@435 | 96 | return Bytecodes::_illegal; |
duke@435 | 97 | } else { |
duke@435 | 98 | return raw_next_special(code); |
duke@435 | 99 | } |
duke@435 | 100 | } |
duke@435 | 101 | Bytecodes::Code raw_next_special(Bytecodes::Code code); |
duke@435 | 102 | |
duke@435 | 103 | // Stream attributes |
duke@435 | 104 | methodHandle method() const { return _method; } |
duke@435 | 105 | |
duke@435 | 106 | int bci() const { return _bci; } |
duke@435 | 107 | int next_bci() const { return _next_bci; } |
duke@435 | 108 | int end_bci() const { return _end_bci; } |
duke@435 | 109 | |
duke@435 | 110 | Bytecodes::Code code() const { return _code; } |
duke@435 | 111 | bool is_wide() const { return _is_wide; } |
duke@435 | 112 | bool is_last_bytecode() const { return _next_bci >= _end_bci; } |
duke@435 | 113 | |
duke@435 | 114 | address bcp() const { return method()->code_base() + _bci; } |
duke@435 | 115 | address next_bcp() { return method()->code_base() + _next_bci; } |
duke@435 | 116 | |
duke@435 | 117 | // State changes |
duke@435 | 118 | void set_next_bci(int bci) { assert(0 <= bci && bci <= method()->code_size(), "illegal bci"); _next_bci = bci; } |
duke@435 | 119 | |
duke@435 | 120 | // Bytecode-specific attributes |
duke@435 | 121 | int dest() const { return bci() + (short)Bytes::get_Java_u2(bcp() + 1); } |
duke@435 | 122 | int dest_w() const { return bci() + (int )Bytes::get_Java_u4(bcp() + 1); } |
duke@435 | 123 | |
duke@435 | 124 | // Unsigned indices, widening |
duke@435 | 125 | int get_index() const { return (is_wide()) ? Bytes::get_Java_u2(bcp() + 2) : bcp()[1]; } |
duke@435 | 126 | int get_index_big() const { return (int)Bytes::get_Java_u2(bcp() + 1); } |
duke@435 | 127 | }; |
duke@435 | 128 | |
duke@435 | 129 | // In BytecodeStream, non-java bytecodes will be translated into the |
duke@435 | 130 | // corresponding java bytecodes. |
duke@435 | 131 | |
duke@435 | 132 | class BytecodeStream: public RawBytecodeStream { |
duke@435 | 133 | public: |
duke@435 | 134 | // Construction |
duke@435 | 135 | BytecodeStream(methodHandle method) : RawBytecodeStream(method) { } |
duke@435 | 136 | |
duke@435 | 137 | // Iteration |
duke@435 | 138 | Bytecodes::Code next() { |
duke@435 | 139 | Bytecodes::Code code; |
duke@435 | 140 | // set reading position |
duke@435 | 141 | _bci = _next_bci; |
duke@435 | 142 | if (is_last_bytecode()) { |
duke@435 | 143 | // indicate end of bytecode stream |
duke@435 | 144 | code = Bytecodes::_illegal; |
duke@435 | 145 | } else { |
duke@435 | 146 | // get bytecode |
duke@435 | 147 | address bcp = BytecodeStream::bcp(); |
duke@435 | 148 | code = Bytecodes::java_code_at(bcp); |
duke@435 | 149 | // set next bytecode position |
duke@435 | 150 | // |
duke@435 | 151 | // note that we cannot advance before having the |
duke@435 | 152 | // tty bytecode otherwise the stepping is wrong! |
duke@435 | 153 | // (carefull: length_for(...) must be used first!) |
duke@435 | 154 | int l = Bytecodes::length_for(code); |
duke@435 | 155 | if (l == 0) l = Bytecodes::length_at(bcp); |
duke@435 | 156 | _next_bci += l; |
duke@435 | 157 | assert(_bci < _next_bci, "length must be > 0"); |
duke@435 | 158 | // set attributes |
duke@435 | 159 | _is_wide = false; |
duke@435 | 160 | // check for special (uncommon) cases |
duke@435 | 161 | if (code == Bytecodes::_wide) { |
duke@435 | 162 | code = (Bytecodes::Code)bcp[1]; |
duke@435 | 163 | _is_wide = true; |
duke@435 | 164 | } |
duke@435 | 165 | assert(Bytecodes::is_java_code(code), "sanity check"); |
duke@435 | 166 | } |
duke@435 | 167 | _code = code; |
duke@435 | 168 | return _code; |
duke@435 | 169 | } |
duke@435 | 170 | |
duke@435 | 171 | bool is_active_breakpoint() const { return Bytecodes::is_active_breakpoint_at(bcp()); } |
duke@435 | 172 | }; |