1 /*
2 * Copyright (c) 2009, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javap;
27
28 import java.util.Arrays;
29 import java.util.HashMap;
30 import java.util.Map;
31
32 import com.sun.tools.classfile.AccessFlags;
33 import com.sun.tools.classfile.Attribute;
34 import com.sun.tools.classfile.Code_attribute;
35 import com.sun.tools.classfile.ConstantPool;
36 import com.sun.tools.classfile.ConstantPoolException;
37 import com.sun.tools.classfile.Descriptor;
38 import com.sun.tools.classfile.Descriptor.InvalidDescriptor;
39 import com.sun.tools.classfile.Instruction;
40 import com.sun.tools.classfile.Method;
41 import com.sun.tools.classfile.StackMapTable_attribute;
42 import com.sun.tools.classfile.StackMapTable_attribute.*;
43
44 import static com.sun.tools.classfile.StackMapTable_attribute.verification_type_info.*;
45
46 /**
47 * Annotate instructions with stack map.
48 *
49 * <p><b>This is NOT part of any supported API.
50 * If you write code that depends on this, you do so at your own risk.
51 * This code and its internal interfaces are subject to change or
52 * deletion without notice.</b>
53 */
54 public class StackMapWriter extends InstructionDetailWriter {
55 static StackMapWriter instance(Context context) {
56 StackMapWriter instance = context.get(StackMapWriter.class);
57 if (instance == null)
58 instance = new StackMapWriter(context);
59 return instance;
60 }
61
62 protected StackMapWriter(Context context) {
63 super(context);
64 context.put(StackMapWriter.class, this);
65 classWriter = ClassWriter.instance(context);
66 }
67
68 public void reset(Code_attribute attr) {
69 setStackMap((StackMapTable_attribute) attr.attributes.get(Attribute.StackMapTable));
70 }
71
72 void setStackMap(StackMapTable_attribute attr) {
73 if (attr == null) {
74 map = null;
75 return;
76 }
77
78 Method m = classWriter.getMethod();
79 Descriptor d = m.descriptor;
80 String[] args;
81 try {
82 ConstantPool cp = classWriter.getClassFile().constant_pool;
83 String argString = d.getParameterTypes(cp);
84 args = argString.substring(1, argString.length() - 1).split("[, ]+");
85 } catch (ConstantPoolException | InvalidDescriptor e) {
86 return;
87 }
88 boolean isStatic = m.access_flags.is(AccessFlags.ACC_STATIC);
89
90 verification_type_info[] initialLocals = new verification_type_info[(isStatic ? 0 : 1) + args.length];
91 if (!isStatic)
92 initialLocals[0] = new CustomVerificationTypeInfo("this");
93 for (int i = 0; i < args.length; i++) {
94 initialLocals[(isStatic ? 0 : 1) + i] =
95 new CustomVerificationTypeInfo(args[i].replace(".", "/"));
96 }
97
98 map = new HashMap<>();
99 StackMapBuilder builder = new StackMapBuilder();
100
101 // using -1 as the pc for the initial frame effectively compensates for
102 // the difference in behavior for the first stack map frame (where the
103 // pc offset is just offset_delta) compared to subsequent frames (where
104 // the pc offset is always offset_delta+1).
105 int pc = -1;
106
107 map.put(pc, new StackMap(initialLocals, empty));
108
109 for (int i = 0; i < attr.entries.length; i++)
110 pc = attr.entries[i].accept(builder, pc);
111 }
112
113 public void writeInitialDetails() {
114 writeDetails(-1);
115 }
116
117 public void writeDetails(Instruction instr) {
118 writeDetails(instr.getPC());
119 }
120
121 private void writeDetails(int pc) {
122 if (map == null)
123 return;
124
125 StackMap m = map.get(pc);
126 if (m != null) {
127 print("StackMap locals: ", m.locals);
128 print("StackMap stack: ", m.stack);
129 }
130
131 }
132
133 void print(String label, verification_type_info[] entries) {
134 print(label);
135 for (int i = 0; i < entries.length; i++) {
136 print(" ");
137 print(entries[i]);
138 }
139 println();
140 }
141
142 void print(verification_type_info entry) {
143 if (entry == null) {
144 print("ERROR");
145 return;
146 }
147
148 switch (entry.tag) {
149 case -1:
150 print(((CustomVerificationTypeInfo) entry).text);
151 break;
152
153 case ITEM_Top:
154 print("top");
155 break;
156
157 case ITEM_Integer:
158 print("int");
159 break;
160
161 case ITEM_Float:
162 print("float");
163 break;
164
165 case ITEM_Long:
166 print("long");
167 break;
168
169 case ITEM_Double:
170 print("double");
171 break;
172
173 case ITEM_Null:
174 print("null");
175 break;
176
177 case ITEM_UninitializedThis:
178 print("uninit_this");
179 break;
180
181 case ITEM_Object:
182 try {
183 ConstantPool cp = classWriter.getClassFile().constant_pool;
184 ConstantPool.CONSTANT_Class_info class_info = cp.getClassInfo(((Object_variable_info) entry).cpool_index);
185 print(cp.getUTF8Value(class_info.name_index));
186 } catch (ConstantPoolException e) {
187 print("??");
188 }
189 break;
190
191 case ITEM_Uninitialized:
192 print(((Uninitialized_variable_info) entry).offset);
193 break;
194 }
195
196 }
197
198 private Map<Integer, StackMap> map;
199 private ClassWriter classWriter;
200
201 class StackMapBuilder
202 implements StackMapTable_attribute.stack_map_frame.Visitor<Integer, Integer> {
203
204 public Integer visit_same_frame(same_frame frame, Integer pc) {
205 int new_pc = pc + frame.getOffsetDelta() + 1;
206 StackMap m = map.get(pc);
207 assert (m != null);
208 map.put(new_pc, m);
209 return new_pc;
210 }
211
212 public Integer visit_same_locals_1_stack_item_frame(same_locals_1_stack_item_frame frame, Integer pc) {
213 int new_pc = pc + frame.getOffsetDelta() + 1;
214 StackMap prev = map.get(pc);
215 assert (prev != null);
216 StackMap m = new StackMap(prev.locals, frame.stack);
217 map.put(new_pc, m);
218 return new_pc;
219 }
220
221 public Integer visit_same_locals_1_stack_item_frame_extended(same_locals_1_stack_item_frame_extended frame, Integer pc) {
222 int new_pc = pc + frame.getOffsetDelta() + 1;
223 StackMap prev = map.get(pc);
224 assert (prev != null);
225 StackMap m = new StackMap(prev.locals, frame.stack);
226 map.put(new_pc, m);
227 return new_pc;
228 }
229
230 public Integer visit_chop_frame(chop_frame frame, Integer pc) {
231 int new_pc = pc + frame.getOffsetDelta() + 1;
232 StackMap prev = map.get(pc);
233 assert (prev != null);
234 int k = 251 - frame.frame_type;
235 verification_type_info[] new_locals = Arrays.copyOf(prev.locals, prev.locals.length - k);
236 StackMap m = new StackMap(new_locals, empty);
237 map.put(new_pc, m);
238 return new_pc;
239 }
240
241 public Integer visit_same_frame_extended(same_frame_extended frame, Integer pc) {
242 int new_pc = pc + frame.getOffsetDelta();
243 StackMap m = map.get(pc);
244 assert (m != null);
245 map.put(new_pc, m);
246 return new_pc;
247 }
248
249 public Integer visit_append_frame(append_frame frame, Integer pc) {
250 int new_pc = pc + frame.getOffsetDelta() + 1;
251 StackMap prev = map.get(pc);
252 assert (prev != null);
253 verification_type_info[] new_locals = new verification_type_info[prev.locals.length + frame.locals.length];
254 System.arraycopy(prev.locals, 0, new_locals, 0, prev.locals.length);
255 System.arraycopy(frame.locals, 0, new_locals, prev.locals.length, frame.locals.length);
256 StackMap m = new StackMap(new_locals, empty);
257 map.put(new_pc, m);
258 return new_pc;
259 }
260
261 public Integer visit_full_frame(full_frame frame, Integer pc) {
262 int new_pc = pc + frame.getOffsetDelta() + 1;
263 StackMap m = new StackMap(frame.locals, frame.stack);
264 map.put(new_pc, m);
265 return new_pc;
266 }
267
268 }
269
270 static class StackMap {
271 StackMap(verification_type_info[] locals, verification_type_info[] stack) {
272 this.locals = locals;
273 this.stack = stack;
274 }
275
276 private final verification_type_info[] locals;
277 private final verification_type_info[] stack;
278 }
279
280 static class CustomVerificationTypeInfo extends verification_type_info {
281 public CustomVerificationTypeInfo(String text) {
282 super(-1);
283 this.text = text;
284 }
285 private String text;
286 }
287
288 private final verification_type_info[] empty = { };
289 }