Mercurial > hg > graal-compiler
comparison src/share/vm/interpreter/bytecodeStream.hpp @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
---|---|
date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | be93aad57795 |
comparison
equal
deleted
inserted
replaced
-1:000000000000 | 0:a61af66fc99e |
---|---|
1 /* | |
2 * Copyright 1997-2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 // A BytecodeStream is used for fast iteration over the bytecodes | |
26 // of a methodOop. | |
27 // | |
28 // Usage: | |
29 // | |
30 // BytecodeStream s(method); | |
31 // Bytecodes::Code c; | |
32 // while ((c = s.next()) >= 0) { | |
33 // ... | |
34 // } | |
35 // | |
36 // A RawBytecodeStream is a simple version of BytecodeStream. | |
37 // It is used ONLY when we know the bytecodes haven't been rewritten | |
38 // yet, such as in the rewriter or the verifier. Currently only the | |
39 // verifier uses this class. | |
40 | |
41 class RawBytecodeStream: StackObj { | |
42 protected: | |
43 // stream buffer | |
44 methodHandle _method; // read from method directly | |
45 | |
46 // reading position | |
47 int _bci; // bci if current bytecode | |
48 int _next_bci; // bci of next bytecode | |
49 int _end_bci; // bci after the current iteration interval | |
50 | |
51 // last bytecode read | |
52 Bytecodes::Code _code; | |
53 bool _is_wide; | |
54 | |
55 public: | |
56 // Construction | |
57 RawBytecodeStream(methodHandle method) : _method(method) { | |
58 set_interval(0, _method->code_size()); | |
59 } | |
60 | |
61 // Iteration control | |
62 void set_interval(int beg_bci, int end_bci) { | |
63 // iterate over the interval [beg_bci, end_bci) | |
64 assert(0 <= beg_bci && beg_bci <= method()->code_size(), "illegal beg_bci"); | |
65 assert(0 <= end_bci && end_bci <= method()->code_size(), "illegal end_bci"); | |
66 // setup of iteration pointers | |
67 _bci = beg_bci; | |
68 _next_bci = beg_bci; | |
69 _end_bci = end_bci; | |
70 } | |
71 void set_start (int beg_bci) { | |
72 set_interval(beg_bci, _method->code_size()); | |
73 } | |
74 | |
75 // Iteration | |
76 // Use raw_next() rather than next() for faster method reference | |
77 Bytecodes::Code raw_next() { | |
78 Bytecodes::Code code; | |
79 // set reading position | |
80 _bci = _next_bci; | |
81 assert(!is_last_bytecode(), "caller should check is_last_bytecode()"); | |
82 | |
83 address bcp = RawBytecodeStream::bcp(); | |
84 code = Bytecodes::code_or_bp_at(bcp); | |
85 | |
86 // set next bytecode position | |
87 int l = Bytecodes::length_for(code); | |
88 if (l > 0 && (_bci + l) <= _end_bci) { | |
89 assert(code != Bytecodes::_wide && code != Bytecodes::_tableswitch | |
90 && code != Bytecodes::_lookupswitch, "can't be special bytecode"); | |
91 _is_wide = false; | |
92 _next_bci += l; | |
93 _code = code; | |
94 return code; | |
95 } else if (code == Bytecodes::_wide && _bci + 1 >= _end_bci) { | |
96 return Bytecodes::_illegal; | |
97 } else { | |
98 return raw_next_special(code); | |
99 } | |
100 } | |
101 Bytecodes::Code raw_next_special(Bytecodes::Code code); | |
102 | |
103 // Stream attributes | |
104 methodHandle method() const { return _method; } | |
105 | |
106 int bci() const { return _bci; } | |
107 int next_bci() const { return _next_bci; } | |
108 int end_bci() const { return _end_bci; } | |
109 | |
110 Bytecodes::Code code() const { return _code; } | |
111 bool is_wide() const { return _is_wide; } | |
112 bool is_last_bytecode() const { return _next_bci >= _end_bci; } | |
113 | |
114 address bcp() const { return method()->code_base() + _bci; } | |
115 address next_bcp() { return method()->code_base() + _next_bci; } | |
116 | |
117 // State changes | |
118 void set_next_bci(int bci) { assert(0 <= bci && bci <= method()->code_size(), "illegal bci"); _next_bci = bci; } | |
119 | |
120 // Bytecode-specific attributes | |
121 int dest() const { return bci() + (short)Bytes::get_Java_u2(bcp() + 1); } | |
122 int dest_w() const { return bci() + (int )Bytes::get_Java_u4(bcp() + 1); } | |
123 | |
124 // Unsigned indices, widening | |
125 int get_index() const { return (is_wide()) ? Bytes::get_Java_u2(bcp() + 2) : bcp()[1]; } | |
126 int get_index_big() const { return (int)Bytes::get_Java_u2(bcp() + 1); } | |
127 }; | |
128 | |
129 // In BytecodeStream, non-java bytecodes will be translated into the | |
130 // corresponding java bytecodes. | |
131 | |
132 class BytecodeStream: public RawBytecodeStream { | |
133 public: | |
134 // Construction | |
135 BytecodeStream(methodHandle method) : RawBytecodeStream(method) { } | |
136 | |
137 // Iteration | |
138 Bytecodes::Code next() { | |
139 Bytecodes::Code code; | |
140 // set reading position | |
141 _bci = _next_bci; | |
142 if (is_last_bytecode()) { | |
143 // indicate end of bytecode stream | |
144 code = Bytecodes::_illegal; | |
145 } else { | |
146 // get bytecode | |
147 address bcp = BytecodeStream::bcp(); | |
148 code = Bytecodes::java_code_at(bcp); | |
149 // set next bytecode position | |
150 // | |
151 // note that we cannot advance before having the | |
152 // tty bytecode otherwise the stepping is wrong! | |
153 // (carefull: length_for(...) must be used first!) | |
154 int l = Bytecodes::length_for(code); | |
155 if (l == 0) l = Bytecodes::length_at(bcp); | |
156 _next_bci += l; | |
157 assert(_bci < _next_bci, "length must be > 0"); | |
158 // set attributes | |
159 _is_wide = false; | |
160 // check for special (uncommon) cases | |
161 if (code == Bytecodes::_wide) { | |
162 code = (Bytecodes::Code)bcp[1]; | |
163 _is_wide = true; | |
164 } | |
165 assert(Bytecodes::is_java_code(code), "sanity check"); | |
166 } | |
167 _code = code; | |
168 return _code; | |
169 } | |
170 | |
171 bool is_active_breakpoint() const { return Bytecodes::is_active_breakpoint_at(bcp()); } | |
172 }; |