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1
19
20 package soot.javaToJimple.toolkits;
21
22 import soot.*;
23 import soot.jimple.*;
24 import java.util.*;
25
26 public class CondTransformer extends BodyTransformer {
27 public CondTransformer (Singletons.Global g) {}
28 public static CondTransformer v() {
29 return G.v().soot_javaToJimple_toolkits_CondTransformer();
30 }
31
32 private static final int SEQ_LENGTH = 6;
33 private Stmt [] stmtSeq = new Stmt[SEQ_LENGTH];
34 private boolean sameGoto = true;
35
36 protected void internalTransform(Body b, String  phaseName, Map options){
37
38 boolean change = true;
40
58
59 while (change){
60 Iterator it = b.getUnits().iterator();
61 int pos = 0;
62 while (it.hasNext()){
63 change = false;
64 Stmt s = (Stmt)it.next();
65 if (testStmtSeq(s, pos)) {
66 pos++;
67 }
68 if (pos == 6) {
69 change = true;
72 break;
73 }
74 }
75 if (change){
76 transformBody(b, (Stmt)it.next());
77 pos = 0;
78 stmtSeq = new Stmt[SEQ_LENGTH];
79 }
80 }
81 }
82
83 private void transformBody(Body b, Stmt next){
84 Stmt newTarget = null;
87 Stmt oldTarget = null;
88 if (sameGoto){
89 newTarget = ((IfStmt)stmtSeq[5]).getTarget();
90 }
91 else {
92 newTarget = next;
93 oldTarget = ((IfStmt)stmtSeq[5]).getTarget();
94 }
95 ((IfStmt)stmtSeq[0]).setTarget(newTarget);
96 ((IfStmt)stmtSeq[1]).setTarget(newTarget);
97
98 for (int i = 2; i <= 5; i++){
99 b.getUnits().remove(stmtSeq[i]);
100 }
101 if (!sameGoto){
102 b.getUnits().insertAfter(Jimple.v().newGotoStmt(oldTarget), stmtSeq[1]);
103 }
104 }
105
106 private boolean testStmtSeq(Stmt s, int pos){
107 switch(pos){
108 case 0: {
109 if (s instanceof IfStmt){
110 stmtSeq[pos] = s;
111 return true;
112 }
113 break;
114 }
115 case 1: {
116 if (s instanceof IfStmt){
117 if (sameTarget(stmtSeq[pos-1], s)){
118 stmtSeq[pos] = s;
119 return true;
120 }
121 }
122 break;
123 }
124 case 2: {
125 if (s instanceof AssignStmt){
126 stmtSeq[pos] = s;
127 if ((((AssignStmt)s).getRightOp() instanceof IntConstant) && (((IntConstant)((AssignStmt)s).getRightOp())).value == 0){
128 sameGoto = false;
129 }
130 return true;
131 }
132 break;
133 }
134 case 3: {
135 if (s instanceof GotoStmt){
136 stmtSeq[pos] = s;
137 return true;
138 }
139 break;
140 }
141 case 4: {
142 if (s instanceof AssignStmt){
143 if (isTarget(((IfStmt)stmtSeq[0]).getTarget(), s) && sameLocal(stmtSeq[2], s)){
144 stmtSeq[pos] = s;
145 return true;
146 }
147 }
148 break;
149 }
150 case 5: {
151 if (s instanceof IfStmt){
152 if (isTarget((Stmt)((GotoStmt)stmtSeq[3]).getTarget(), s) && sameCondLocal(stmtSeq[4], s) && (((IfStmt)s).getCondition() instanceof EqExpr)){
153 stmtSeq[pos] = s;
154 return true;
155 }
156 else if (isTarget((Stmt)((GotoStmt)stmtSeq[3]).getTarget(), s) && sameCondLocal(stmtSeq[4], s)){
157 stmtSeq[pos] = s;
158 sameGoto = false;
159 return true;
160 }
161 }
162 break;
163 }
164
165 default: {
166 break;
167 }
168 }
169 return false;
170 }
171
172 private boolean sameTarget(Stmt s1, Stmt s2){
173 IfStmt is1 = (IfStmt)s1;
174 IfStmt is2 = (IfStmt)s2;
175 if (is1.getTarget().equals(is2.getTarget())){
176 return true;
177 }
178 return false;
179 }
180
181 private boolean isTarget(Stmt s1, Stmt s){
182 if (s1.equals(s)){
183 return true;
184 }
185 return false;
186 }
187
188 private boolean sameLocal(Stmt s1, Stmt s2){
189 AssignStmt as1 = (AssignStmt)s1;
190 AssignStmt as2 = (AssignStmt)s2;
191 if (as1.getLeftOp().equals(as2.getLeftOp())){
192 return true;
193 }
194 return false;
195 }
196
197 private boolean sameCondLocal(Stmt s1, Stmt s2){
198 AssignStmt as1 = (AssignStmt)s1;
199 IfStmt is2 = (IfStmt)s2;
200 if (is2.getCondition() instanceof BinopExpr){
201 BinopExpr bs2 = (BinopExpr)is2.getCondition();
202 if (as1.getLeftOp().equals(bs2.getOp1())){
203 return true;
204 }
205 }
206 return false;
207 }
208 }
209 |
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