1 /*
2 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
3 * @LastModified: Oct 2017
4 */
5 /*
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements. See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License. You may obtain a copy of the License at
12 *
13 * http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 */
21
22 package com.sun.org.apache.bcel.internal.util;
23
24 import java.io.PrintWriter;
25 import java.util.ArrayList;
26 import java.util.HashMap;
27 import java.util.List;
28 import java.util.Locale;
29 import java.util.Map;
30
31 import com.sun.org.apache.bcel.internal.Const;
32 import com.sun.org.apache.bcel.internal.classfile.Utility;
33 import com.sun.org.apache.bcel.internal.generic.AllocationInstruction;
34 import com.sun.org.apache.bcel.internal.generic.ArrayInstruction;
35 import com.sun.org.apache.bcel.internal.generic.ArrayType;
36 import com.sun.org.apache.bcel.internal.generic.BranchHandle;
37 import com.sun.org.apache.bcel.internal.generic.BranchInstruction;
38 import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
39 import com.sun.org.apache.bcel.internal.generic.CPInstruction;
40 import com.sun.org.apache.bcel.internal.generic.CodeExceptionGen;
41 import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
42 import com.sun.org.apache.bcel.internal.generic.ConstantPushInstruction;
43 import com.sun.org.apache.bcel.internal.generic.EmptyVisitor;
44 import com.sun.org.apache.bcel.internal.generic.FieldInstruction;
45 import com.sun.org.apache.bcel.internal.generic.IINC;
46 import com.sun.org.apache.bcel.internal.generic.INSTANCEOF;
47 import com.sun.org.apache.bcel.internal.generic.Instruction;
48 import com.sun.org.apache.bcel.internal.generic.InstructionConst;
49 import com.sun.org.apache.bcel.internal.generic.InstructionHandle;
50 import com.sun.org.apache.bcel.internal.generic.InvokeInstruction;
51 import com.sun.org.apache.bcel.internal.generic.LDC;
52 import com.sun.org.apache.bcel.internal.generic.LDC2_W;
53 import com.sun.org.apache.bcel.internal.generic.LocalVariableInstruction;
54 import com.sun.org.apache.bcel.internal.generic.MULTIANEWARRAY;
55 import com.sun.org.apache.bcel.internal.generic.MethodGen;
56 import com.sun.org.apache.bcel.internal.generic.NEWARRAY;
57 import com.sun.org.apache.bcel.internal.generic.ObjectType;
58 import com.sun.org.apache.bcel.internal.generic.RET;
59 import com.sun.org.apache.bcel.internal.generic.ReturnInstruction;
60 import com.sun.org.apache.bcel.internal.generic.Select;
61 import com.sun.org.apache.bcel.internal.generic.Type;
62
63 /**
64 * Factory creates il.append() statements, and sets instruction targets.
65 * A helper class for BCELifier.
66 *
67 * @see BCELifier
68 * @version $Id: BCELFactory.java 1749603 2016-06-21 20:50:19Z ggregory $
69 */
70 class BCELFactory extends EmptyVisitor {
71
72 private static final String CONSTANT_PREFIX = Const.class.getSimpleName()+".";
73 private final MethodGen _mg;
74 private final PrintWriter _out;
75 private final ConstantPoolGen _cp;
76
77
78 BCELFactory(final MethodGen mg, final PrintWriter out) {
79 _mg = mg;
80 _cp = mg.getConstantPool();
81 _out = out;
82 }
83
84 private final Map<Instruction, InstructionHandle> branch_map = new HashMap<>();
85
86
87 public void start() {
88 if (!_mg.isAbstract() && !_mg.isNative()) {
89 for (InstructionHandle ih = _mg.getInstructionList().getStart(); ih != null; ih = ih
90 .getNext()) {
91 final Instruction i = ih.getInstruction();
92 if (i instanceof BranchInstruction) {
93 branch_map.put(i, ih); // memorize container
94 }
95 if (ih.hasTargeters()) {
96 if (i instanceof BranchInstruction) {
97 _out.println(" InstructionHandle ih_" + ih.getPosition() + ";");
98 } else {
99 _out.print(" InstructionHandle ih_" + ih.getPosition() + " = ");
100 }
101 } else {
102 _out.print(" ");
103 }
104 if (!visitInstruction(i)) {
105 i.accept(this);
106 }
107 }
108 updateBranchTargets();
109 updateExceptionHandlers();
110 }
111 }
112
113
114 private boolean visitInstruction( final Instruction i ) {
115 final short opcode = i.getOpcode();
116 if ((InstructionConst.getInstruction(opcode) != null)
117 && !(i instanceof ConstantPushInstruction) && !(i instanceof ReturnInstruction)) { // Handled below
118 _out.println("il.append(InstructionConst."
119 + i.getName().toUpperCase(Locale.ENGLISH) + ");");
120 return true;
121 }
122 return false;
123 }
124
125
126 @Override
127 public void visitLocalVariableInstruction( final LocalVariableInstruction i ) {
128 final short opcode = i.getOpcode();
129 final Type type = i.getType(_cp);
130 if (opcode == Const.IINC) {
131 _out.println("il.append(new IINC(" + i.getIndex() + ", " + ((IINC) i).getIncrement()
132 + "));");
133 } else {
134 final String kind = (opcode < Const.ISTORE) ? "Load" : "Store";
135 _out.println("il.append(_factory.create" + kind + "(" + BCELifier.printType(type)
136 + ", " + i.getIndex() + "));");
137 }
138 }
139
140
141 @Override
142 public void visitArrayInstruction( final ArrayInstruction i ) {
143 final short opcode = i.getOpcode();
144 final Type type = i.getType(_cp);
145 final String kind = (opcode < Const.IASTORE) ? "Load" : "Store";
146 _out.println("il.append(_factory.createArray" + kind + "(" + BCELifier.printType(type)
147 + "));");
148 }
149
150
151 @Override
152 public void visitFieldInstruction( final FieldInstruction i ) {
153 final short opcode = i.getOpcode();
154 final String class_name = i.getReferenceType(_cp).getSignature();
155 final String field_name = i.getFieldName(_cp);
156 final Type type = i.getFieldType(_cp);
157 _out.println("il.append(_factory.createFieldAccess(\"" + class_name + "\", \"" + field_name
158 + "\", " + BCELifier.printType(type) + ", " + CONSTANT_PREFIX
159 + Const.getOpcodeName(opcode).toUpperCase(Locale.ENGLISH) + "));");
160 }
161
162
163 @Override
164 public void visitInvokeInstruction( final InvokeInstruction i ) {
165 final short opcode = i.getOpcode();
166 final String class_name = i.getReferenceType(_cp).getSignature();
167 final String method_name = i.getMethodName(_cp);
168 final Type type = i.getReturnType(_cp);
169 final Type[] arg_types = i.getArgumentTypes(_cp);
170 _out.println("il.append(_factory.createInvoke(\"" + class_name + "\", \"" + method_name
171 + "\", " + BCELifier.printType(type) + ", "
172 + BCELifier.printArgumentTypes(arg_types) + ", " + CONSTANT_PREFIX
173 + Const.getOpcodeName(opcode).toUpperCase(Locale.ENGLISH) + "));");
174 }
175
176
177 @Override
178 @SuppressWarnings("fallthrough") // by design for case Const.ANEWARRAY
179 public void visitAllocationInstruction( final AllocationInstruction i ) {
180 Type type;
181 if (i instanceof CPInstruction) {
182 type = ((CPInstruction) i).getType(_cp);
183 } else {
184 type = ((NEWARRAY) i).getType();
185 }
186 final short opcode = ((Instruction) i).getOpcode();
187 int dim = 1;
188 switch (opcode) {
189 case Const.NEW:
190 _out.println("il.append(_factory.createNew(\"" + ((ObjectType) type).getClassName()
191 + "\"));");
192 break;
193 case Const.MULTIANEWARRAY:
194 dim = ((MULTIANEWARRAY) i).getDimensions();
195 //$FALL-THROUGH$
196 case Const.ANEWARRAY:
197 case Const.NEWARRAY:
198 if (type instanceof ArrayType) {
199 type = ((ArrayType) type).getBasicType();
200 }
201 _out.println("il.append(_factory.createNewArray(" + BCELifier.printType(type)
202 + ", (short) " + dim + "));");
203 break;
204 default:
205 throw new RuntimeException("Oops: " + opcode);
206 }
207 }
208
209
210 private void createConstant( final Object value ) {
211 String embed = value.toString();
212 if (value instanceof String) {
213 embed = '"' + Utility.convertString(embed) + '"';
214 } else if (value instanceof Character) {
215 embed = "(char)0x" + Integer.toHexString(((Character) value).charValue());
216 } else if (value instanceof Float) {
217 embed += "f";
218 } else if (value instanceof Long) {
219 embed += "L";
220 } else if (value instanceof ObjectType) {
221 final ObjectType ot = (ObjectType) value;
222 embed = "new ObjectType(\""+ot.getClassName()+"\")";
223 }
224
225 _out.println("il.append(new PUSH(_cp, " + embed + "));");
226 }
227
228
229 @Override
230 public void visitLDC( final LDC i ) {
231 createConstant(i.getValue(_cp));
232 }
233
234
235 @Override
236 public void visitLDC2_W( final LDC2_W i ) {
237 createConstant(i.getValue(_cp));
238 }
239
240
241 @Override
242 public void visitConstantPushInstruction( final ConstantPushInstruction i ) {
243 createConstant(i.getValue());
244 }
245
246
247 @Override
248 public void visitINSTANCEOF( final INSTANCEOF i ) {
249 final Type type = i.getType(_cp);
250 _out.println("il.append(new INSTANCEOF(_cp.addClass(" + BCELifier.printType(type) + ")));");
251 }
252
253
254 @Override
255 public void visitCHECKCAST( final CHECKCAST i ) {
256 final Type type = i.getType(_cp);
257 _out.println("il.append(_factory.createCheckCast(" + BCELifier.printType(type) + "));");
258 }
259
260
261 @Override
262 public void visitReturnInstruction( final ReturnInstruction i ) {
263 final Type type = i.getType(_cp);
264 _out.println("il.append(_factory.createReturn(" + BCELifier.printType(type) + "));");
265 }
266
267 // Memorize BranchInstructions that need an update
268 private final List<BranchInstruction> branches = new ArrayList<>();
269
270
271 @Override
272 public void visitBranchInstruction( final BranchInstruction bi ) {
273 final BranchHandle bh = (BranchHandle) branch_map.get(bi);
274 final int pos = bh.getPosition();
275 final String name = bi.getName() + "_" + pos;
276 if (bi instanceof Select) {
277 final Select s = (Select) bi;
278 branches.add(bi);
279 final StringBuilder args = new StringBuilder("new int[] { ");
280 final int[] matchs = s.getMatchs();
281 for (int i = 0; i < matchs.length; i++) {
282 args.append(matchs[i]);
283 if (i < matchs.length - 1) {
284 args.append(", ");
285 }
286 }
287 args.append(" }");
288 _out.print("Select " + name + " = new " + bi.getName().toUpperCase(Locale.ENGLISH)
289 + "(" + args + ", new InstructionHandle[] { ");
290 for (int i = 0; i < matchs.length; i++) {
291 _out.print("null");
292 if (i < matchs.length - 1) {
293 _out.print(", ");
294 }
295 }
296 _out.println(" }, null);");
297 } else {
298 final int t_pos = bh.getTarget().getPosition();
299 String target;
300 if (pos > t_pos) {
301 target = "ih_" + t_pos;
302 } else {
303 branches.add(bi);
304 target = "null";
305 }
306 _out.println(" BranchInstruction " + name + " = _factory.createBranchInstruction("
307 + CONSTANT_PREFIX + bi.getName().toUpperCase(Locale.ENGLISH) + ", " + target
308 + ");");
309 }
310 if (bh.hasTargeters()) {
311 _out.println(" ih_" + pos + " = il.append(" + name + ");");
312 } else {
313 _out.println(" il.append(" + name + ");");
314 }
315 }
316
317
318 @Override
319 public void visitRET( final RET i ) {
320 _out.println("il.append(new RET(" + i.getIndex() + ")));");
321 }
322
323
324 private void updateBranchTargets() {
325 for (final BranchInstruction bi : branches) {
326 final BranchHandle bh = (BranchHandle) branch_map.get(bi);
327 final int pos = bh.getPosition();
328 final String name = bi.getName() + "_" + pos;
329 int t_pos = bh.getTarget().getPosition();
330 _out.println(" " + name + ".setTarget(ih_" + t_pos + ");");
331 if (bi instanceof Select) {
332 final InstructionHandle[] ihs = ((Select) bi).getTargets();
333 for (int j = 0; j < ihs.length; j++) {
334 t_pos = ihs[j].getPosition();
335 _out.println(" " + name + ".setTarget(" + j + ", ih_" + t_pos + ");");
336 }
337 }
338 }
339 }
340
341
342 private void updateExceptionHandlers() {
343 final CodeExceptionGen[] handlers = _mg.getExceptionHandlers();
344 for (final CodeExceptionGen h : handlers) {
345 final String type = (h.getCatchType() == null) ? "null" : BCELifier.printType(h
346 .getCatchType());
347 _out.println(" method.addExceptionHandler(" + "ih_" + h.getStartPC().getPosition()
348 + ", " + "ih_" + h.getEndPC().getPosition() + ", " + "ih_"
349 + h.getHandlerPC().getPosition() + ", " + type + ");");
350 }
351 }
352 }