1 /*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5 package com.sun.org.apache.bcel.internal.util;
6
7 import com.sun.org.apache.bcel.internal.generic.*;
8 import com.sun.org.apache.bcel.internal.classfile.Utility;
9 import com.sun.org.apache.bcel.internal.Constants;
10 import java.io.PrintWriter;
11 import java.util.*;
12
13 /* ====================================================================
14 * The Apache Software License, Version 1.1
15 *
16 * Copyright (c) 2002 The Apache Software Foundation. All rights
17 * reserved.
18 *
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
21 * are met:
22 *
23 * 1. Redistributions of source code must retain the above copyright
24 * notice, this list of conditions and the following disclaimer.
25 *
26 * 2. Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in
28 * the documentation and/or other materials provided with the
29 * distribution.
30 *
31 * 3. The end-user documentation included with the redistribution,
32 * if any, must include the following acknowledgment:
33 * "This product includes software developed by the
34 * Apache Software Foundation (http://www.apache.org/)."
35 * Alternately, this acknowledgment may appear in the software itself,
36 * if and wherever such third-party acknowledgments normally appear.
37 *
38 * 4. The names "Apache" and "Apache Software Foundation" and
39 * "Apache BCEL" must not be used to endorse or promote products
40 * derived from this software without prior written permission. For
41 * written permission, please contact apache@apache.org.
42 *
43 * 5. Products derived from this software may not be called "Apache",
44 * "Apache BCEL", nor may "Apache" appear in their name, without
45 * prior written permission of the Apache Software Foundation.
46 *
47 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
48 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
49 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
50 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
51 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
52 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
53 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
54 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
55 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
56 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
57 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 * ====================================================================
60 *
61 * This software consists of voluntary contributions made by many
62 * individuals on behalf of the Apache Software Foundation. For more
63 * information on the Apache Software Foundation, please see
64 * <http://www.apache.org/>.
65 */
66
67 /**
68 * Factory creates il.append() statements, and sets instruction targets.
69 * A helper class for BCELifier.
70 *
71 * @see BCELifier
72 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
73 */
74 class BCELFactory extends EmptyVisitor {
75 private MethodGen _mg;
76 private PrintWriter _out;
77 private ConstantPoolGen _cp;
78
79 BCELFactory(MethodGen mg, PrintWriter out) {
80 _mg = mg;
81 _cp = mg.getConstantPool();
82 _out = out;
83 }
84
85 private HashMap branch_map = new HashMap(); // Map<Instruction, InstructionHandle>
86
87 public void start() {
88 if(!_mg.isAbstract() && !_mg.isNative()) {
89 for(InstructionHandle ih = _mg.getInstructionList().getStart();
90 ih != null; ih = ih.getNext()) {
91 Instruction i = ih.getInstruction();
92
93 if(i instanceof BranchInstruction) {
94 branch_map.put(i, ih); // memorize container
95 }
96
97 if(ih.hasTargeters()) {
98 if(i instanceof BranchInstruction) {
99 _out.println(" InstructionHandle ih_" + ih.getPosition() + ";");
100 } else {
101 _out.print(" InstructionHandle ih_" + ih.getPosition() + " = ");
102 }
103 } else {
104 _out.print(" ");
105 }
106
107 if(!visitInstruction(i))
108 i.accept(this);
109 }
110
111 updateBranchTargets();
112 updateExceptionHandlers();
113 }
114 }
115
116 private boolean visitInstruction(Instruction i) {
117 short opcode = i.getOpcode();
118
119 if((InstructionConstants.INSTRUCTIONS[opcode] != null) &&
120 !(i instanceof ConstantPushInstruction) &&
121 !(i instanceof ReturnInstruction)) { // Handled below
122 _out.println("il.append(InstructionConstants." +
123 i.getName().toUpperCase() + ");");
124 return true;
125 }
126
127 return false;
128 }
129
130 public void visitLocalVariableInstruction(LocalVariableInstruction i) {
131 short opcode = i.getOpcode();
132 Type type = i.getType(_cp);
133
134 if(opcode == Constants.IINC) {
135 _out.println("il.append(new IINC(" + i.getIndex() + ", " +
136 ((IINC)i).getIncrement() + "));");
137 } else {
138 String kind = (opcode < Constants.ISTORE)? "Load" : "Store";
139 _out.println("il.append(_factory.create" + kind + "(" +
140 BCELifier.printType(type) + ", " +
141 i.getIndex() + "));");
142 }
143 }
144
145 public void visitArrayInstruction(ArrayInstruction i) {
146 short opcode = i.getOpcode();
147 Type type = i.getType(_cp);
148 String kind = (opcode < Constants.IASTORE)? "Load" : "Store";
149
150 _out.println("il.append(_factory.createArray" + kind + "(" +
151 BCELifier.printType(type) + "));");
152 }
153
154 public void visitFieldInstruction(FieldInstruction i) {
155 short opcode = i.getOpcode();
156
157 String class_name = i.getClassName(_cp);
158 String field_name = i.getFieldName(_cp);
159 Type type = i.getFieldType(_cp);
160
161 _out.println("il.append(_factory.createFieldAccess(\"" +
162 class_name + "\", \"" + field_name + "\", " +
163 BCELifier.printType(type) + ", " +
164 "Constants." + Constants.OPCODE_NAMES[opcode].toUpperCase() +
165 "));");
166 }
167
168 public void visitInvokeInstruction(InvokeInstruction i) {
169 short opcode = i.getOpcode();
170 String class_name = i.getClassName(_cp);
171 String method_name = i.getMethodName(_cp);
172 Type type = i.getReturnType(_cp);
173 Type[] arg_types = i.getArgumentTypes(_cp);
174
175 _out.println("il.append(_factory.createInvoke(\"" +
176 class_name + "\", \"" + method_name + "\", " +
177 BCELifier.printType(type) + ", " +
178 BCELifier.printArgumentTypes(arg_types) + ", " +
179 "Constants." + Constants.OPCODE_NAMES[opcode].toUpperCase() +
180 "));");
181 }
182
183 public void visitAllocationInstruction(AllocationInstruction i) {
184 Type type;
185
186 if(i instanceof CPInstruction) {
187 type = ((CPInstruction)i).getType(_cp);
188 } else {
189 type = ((NEWARRAY)i).getType();
190 }
191
192 short opcode = ((Instruction)i).getOpcode();
193 int dim = 1;
194
195 switch(opcode) {
196 case Constants.NEW:
197 _out.println("il.append(_factory.createNew(\"" +
198 ((ObjectType)type).getClassName() + "\"));");
199 break;
200
201 case Constants.MULTIANEWARRAY:
202 dim = ((MULTIANEWARRAY)i).getDimensions();
203
204 case Constants.ANEWARRAY:
205 case Constants.NEWARRAY:
206 _out.println("il.append(_factory.createNewArray(" +
207 BCELifier.printType(type) + ", (short) " + dim + "));");
208 break;
209
210 default:
211 throw new RuntimeException("Oops: " + opcode);
212 }
213 }
214
215 private void createConstant(Object value) {
216 String embed = value.toString();
217
218 if(value instanceof String)
219 embed = '"' + Utility.convertString(value.toString()) + '"';
220 else if(value instanceof Character)
221 embed = "(char)0x" + Integer.toHexString(((Character)value).charValue());
222
223 _out.println("il.append(new PUSH(_cp, " + embed + "));");
224 }
225
226 public void visitLDC(LDC i) {
227 createConstant(i.getValue(_cp));
228 }
229
230 public void visitLDC2_W(LDC2_W i) {
231 createConstant(i.getValue(_cp));
232 }
233
234 public void visitConstantPushInstruction(ConstantPushInstruction i) {
235 createConstant(i.getValue());
236 }
237
238 public void visitINSTANCEOF(INSTANCEOF i) {
239 Type type = i.getType(_cp);
240
241 _out.println("il.append(new INSTANCEOF(_cp.addClass(" +
242 BCELifier.printType(type) + ")));");
243 }
244
245 public void visitCHECKCAST(CHECKCAST i) {
246 Type type = i.getType(_cp);
247
248 _out.println("il.append(_factory.createCheckCast(" +
249 BCELifier.printType(type) + "));");
250 }
251
252 public void visitReturnInstruction(ReturnInstruction i) {
253 Type type = i.getType(_cp);
254
255 _out.println("il.append(_factory.createReturn(" +
256 BCELifier.printType(type) + "));");
257 }
258
259 // Memorize BranchInstructions that need an update
260 private ArrayList branches = new ArrayList();
261
262 public void visitBranchInstruction(BranchInstruction bi) {
263 BranchHandle bh = (BranchHandle)branch_map.get(bi);
264 int pos = bh.getPosition();
265 String name = bi.getName() + "_" + pos;
266
267 if(bi instanceof Select) {
268 Select s = (Select)bi;
269 branches.add(bi);
270
271 StringBuffer args = new StringBuffer("new int[] { ");
272 int[] matchs = s.getMatchs();
273
274 for(int i=0; i < matchs.length; i++) {
275 args.append(matchs[i]);
276
277 if(i < matchs.length - 1)
278 args.append(", ");
279 }
280
281 args.append(" }");
282
283 _out.print(" Select " + name + " = new " +
284 bi.getName().toUpperCase() + "(" + args +
285 ", new InstructionHandle[] { ");
286
287 for(int i=0; i < matchs.length; i++) {
288 _out.print("null");
289
290 if(i < matchs.length - 1)
291 _out.print(", ");
292 }
293
294 _out.println(");");
295 } else {
296 int t_pos = bh.getTarget().getPosition();
297 String target;
298
299 if(pos > t_pos) {
300 target = "ih_" + t_pos;
301 } else {
302 branches.add(bi);
303 target = "null";
304 }
305
306 _out.println(" BranchInstruction " + name +
307 " = _factory.createBranchInstruction(" +
308 "Constants." + bi.getName().toUpperCase() + ", " +
309 target + ");");
310 }
311
312 if(bh.hasTargeters())
313 _out.println(" ih_" + pos + " = il.append(" + name + ");");
314 else
315 _out.println(" il.append(" + name + ");");
316 }
317
318 public void visitRET(RET i) {
319 _out.println("il.append(new RET(" + i.getIndex() + ")));");
320 }
321
322 private void updateBranchTargets() {
323 for(Iterator i = branches.iterator(); i.hasNext(); ) {
324 BranchInstruction bi = (BranchInstruction)i.next();
325 BranchHandle bh = (BranchHandle)branch_map.get(bi);
326 int pos = bh.getPosition();
327 String name = bi.getName() + "_" + pos;
328 int t_pos = bh.getTarget().getPosition();
329
330 _out.println(" " + name + ".setTarget(ih_" + t_pos + ");");
331
332 if(bi instanceof Select) {
333 InstructionHandle[] ihs = ((Select)bi).getTargets();
334
335 for(int j = 0; j < ihs.length; j++) {
336 t_pos = ihs[j].getPosition();
337
338 _out.println(" " + name + ".setTarget(" + j +
339 ", ih_" + t_pos + ");");
340 }
341 }
342 }
343 }
344
345 private void updateExceptionHandlers() {
346 CodeExceptionGen[] handlers = _mg.getExceptionHandlers();
347
348 for(int i=0; i < handlers.length; i++) {
349 CodeExceptionGen h = handlers[i];
350 String type = (h.getCatchType() == null)?
351 "null" : BCELifier.printType(h.getCatchType());
352
353 _out.println(" method.addExceptionHandler(" +
354 "ih_" + h.getStartPC().getPosition() + ", " +
355 "ih_" + h.getEndPC().getPosition() + ", " +
356 "ih_" + h.getHandlerPC().getPosition() + ", " +
357 type + ");");
358 }
359 }
360 }