Wed, 03 Jul 2019 20:42:37 +0800
Merge
1 /*
2 * Copyright (c) 1997, 2016, 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
21 * questions.
22 *
23 */
25 /*
26 * This file has been modified by Loongson Technology in 2015. These
27 * modifications are Copyright (c) 2015 Loongson Technology, and are made
28 * available on the same license terms set forth above.
29 */
31 #ifndef SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP
32 #define SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP
34 #include "interpreter/bytecode.hpp"
35 #include "memory/allocation.hpp"
36 #include "oops/method.hpp"
37 #include "runtime/handles.inline.hpp"
38 #ifdef TARGET_ARCH_x86
39 # include "bytes_x86.hpp"
40 #endif
41 #ifdef TARGET_ARCH_mips
42 # include "bytes_mips.hpp"
43 #endif
44 #ifdef TARGET_ARCH_sparc
45 # include "bytes_sparc.hpp"
46 #endif
47 #ifdef TARGET_ARCH_zero
48 # include "bytes_zero.hpp"
49 #endif
50 #ifdef TARGET_ARCH_arm
51 # include "bytes_arm.hpp"
52 #endif
53 #ifdef TARGET_ARCH_ppc
54 # include "bytes_ppc.hpp"
55 #endif
57 // A BytecodeStream is used for fast iteration over the bytecodes
58 // of a Method*.
59 //
60 // Usage:
61 //
62 // BytecodeStream s(method);
63 // Bytecodes::Code c;
64 // while ((c = s.next()) >= 0) {
65 // ...
66 // }
68 // A RawBytecodeStream is a simple version of BytecodeStream.
69 // It is used ONLY when we know the bytecodes haven't been rewritten
70 // yet, such as in the rewriter or the verifier.
72 // Here is the common base class for both RawBytecodeStream and BytecodeStream:
73 class BaseBytecodeStream: StackObj {
74 protected:
75 // stream buffer
76 methodHandle _method; // read from method directly
78 // reading position
79 int _bci; // bci if current bytecode
80 int _next_bci; // bci of next bytecode
81 int _end_bci; // bci after the current iteration interval
83 // last bytecode read
84 Bytecodes::Code _raw_code;
85 bool _is_wide;
86 bool _is_raw; // false in 'cooked' BytecodeStream
88 // Construction
89 BaseBytecodeStream(methodHandle method) : _method(method) {
90 set_interval(0, _method->code_size());
91 _is_raw = false;
92 }
94 public:
95 // Iteration control
96 void set_interval(int beg_bci, int end_bci) {
97 // iterate over the interval [beg_bci, end_bci)
98 assert(0 <= beg_bci && beg_bci <= method()->code_size(), "illegal beg_bci");
99 assert(0 <= end_bci && end_bci <= method()->code_size(), "illegal end_bci");
100 // setup of iteration pointers
101 _bci = beg_bci;
102 _next_bci = beg_bci;
103 _end_bci = end_bci;
104 }
105 void set_start (int beg_bci) {
106 set_interval(beg_bci, _method->code_size());
107 }
109 bool is_raw() const { return _is_raw; }
111 // Stream attributes
112 methodHandle method() const { return _method; }
114 int bci() const { return _bci; }
115 int next_bci() const { return _next_bci; }
116 int end_bci() const { return _end_bci; }
118 Bytecodes::Code raw_code() const { return _raw_code; }
119 bool is_wide() const { return _is_wide; }
120 int instruction_size() const { return (_next_bci - _bci); }
121 bool is_last_bytecode() const { return _next_bci >= _end_bci; }
123 address bcp() const { return method()->code_base() + _bci; }
124 Bytecode bytecode() const { return Bytecode(_method(), bcp()); }
126 // State changes
127 void set_next_bci(int bci) { assert(0 <= bci && bci <= method()->code_size(), "illegal bci"); _next_bci = bci; }
129 // Bytecode-specific attributes
130 int dest() const { return bci() + bytecode().get_offset_s2(raw_code()); }
131 int dest_w() const { return bci() + bytecode().get_offset_s4(raw_code()); }
133 // One-byte indices.
134 int get_index_u1() const { assert_raw_index_size(1); return *(jubyte*)(bcp()+1); }
136 protected:
137 void assert_raw_index_size(int size) const NOT_DEBUG_RETURN;
138 void assert_raw_stream(bool want_raw) const NOT_DEBUG_RETURN;
139 };
141 class RawBytecodeStream: public BaseBytecodeStream {
142 public:
143 // Construction
144 RawBytecodeStream(methodHandle method) : BaseBytecodeStream(method) {
145 _is_raw = true;
146 }
148 public:
149 // Iteration
150 // Use raw_next() rather than next() for faster method reference
151 Bytecodes::Code raw_next() {
152 Bytecodes::Code code;
153 // set reading position
154 _bci = _next_bci;
155 assert(!is_last_bytecode(), "caller should check is_last_bytecode()");
157 address bcp = this->bcp();
158 code = Bytecodes::code_or_bp_at(bcp);
160 // set next bytecode position
161 int len = Bytecodes::length_for(code);
162 if (len > 0 && (_bci <= _end_bci - len)) {
163 assert(code != Bytecodes::_wide && code != Bytecodes::_tableswitch
164 && code != Bytecodes::_lookupswitch, "can't be special bytecode");
165 _is_wide = false;
166 _next_bci += len;
167 if (_next_bci <= _bci) { // Check for integer overflow
168 code = Bytecodes::_illegal;
169 }
170 _raw_code = code;
171 return code;
172 } else {
173 return raw_next_special(code);
174 }
175 }
176 Bytecodes::Code raw_next_special(Bytecodes::Code code);
178 // Unsigned indices, widening, with no swapping of bytes
179 int get_index() const { return (is_wide()) ? get_index_u2_raw(bcp() + 2) : get_index_u1(); }
180 // Get an unsigned 2-byte index, with no swapping of bytes.
181 int get_index_u2() const { assert(!is_wide(), ""); return get_index_u2_raw(bcp() + 1); }
183 private:
184 int get_index_u2_raw(address p) const {
185 assert_raw_index_size(2); assert_raw_stream(true);
186 return Bytes::get_Java_u2(p);
187 }
188 };
190 // In BytecodeStream, non-java bytecodes will be translated into the
191 // corresponding java bytecodes.
193 class BytecodeStream: public BaseBytecodeStream {
194 Bytecodes::Code _code;
196 public:
197 // Construction
198 BytecodeStream(methodHandle method) : BaseBytecodeStream(method) { }
200 // Iteration
201 Bytecodes::Code next() {
202 Bytecodes::Code raw_code, code;
203 // set reading position
204 _bci = _next_bci;
205 if (is_last_bytecode()) {
206 // indicate end of bytecode stream
207 raw_code = code = Bytecodes::_illegal;
208 } else {
209 // get bytecode
210 address bcp = this->bcp();
211 raw_code = Bytecodes::code_at(_method(), bcp);
212 code = Bytecodes::java_code(raw_code);
213 // set next bytecode position
214 //
215 // note that we cannot advance before having the
216 // tty bytecode otherwise the stepping is wrong!
217 // (carefull: length_for(...) must be used first!)
218 int len = Bytecodes::length_for(code);
219 if (len == 0) len = Bytecodes::length_at(_method(), bcp);
220 if (len <= 0 || (_bci > _end_bci - len) || (_bci - len >= _next_bci)) {
221 raw_code = code = Bytecodes::_illegal;
222 } else {
223 _next_bci += len;
224 assert(_bci < _next_bci, "length must be > 0");
225 // set attributes
226 _is_wide = false;
227 // check for special (uncommon) cases
228 if (code == Bytecodes::_wide) {
229 raw_code = (Bytecodes::Code)bcp[1];
230 code = raw_code; // wide BCs are always Java-normal
231 _is_wide = true;
232 }
233 assert(Bytecodes::is_java_code(code), "sanity check");
234 }
235 }
236 _raw_code = raw_code;
237 _code = code;
238 return _code;
239 }
241 bool is_active_breakpoint() const { return Bytecodes::is_active_breakpoint_at(bcp()); }
242 Bytecodes::Code code() const { return _code; }
244 // Unsigned indices, widening
245 int get_index() const { return is_wide() ? bytecode().get_index_u2(raw_code(), true) : get_index_u1(); }
246 // Get an unsigned 2-byte index, swapping the bytes if necessary.
247 int get_index_u2() const { assert_raw_stream(false);
248 return bytecode().get_index_u2(raw_code(), false); }
249 // Get an unsigned 2-byte index in native order.
250 int get_index_u2_cpcache() const { assert_raw_stream(false);
251 return bytecode().get_index_u2_cpcache(raw_code()); }
252 int get_index_u4() const { assert_raw_stream(false);
253 return bytecode().get_index_u4(raw_code()); }
254 bool has_index_u4() const { return bytecode().has_index_u4(raw_code()); }
255 };
257 #endif // SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP