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1
19
20 package edu.umd.cs.findbugs.ba.npe;
21
22 import java.util.Collection  ;
23 import java.util.Collections ;
24 import java.util.HashMap ;
25 import java.util.Iterator ;
26 import java.util.Map ;
27
28 import edu.umd.cs.findbugs.annotations.CheckForNull;
29 import edu.umd.cs.findbugs.annotations.NonNull;
30 import edu.umd.cs.findbugs.ba.Frame;
31 import edu.umd.cs.findbugs.ba.vna.ValueNumber;
32 import edu.umd.cs.findbugs.ba.vna.ValueNumberFrame;
33 import edu.umd.cs.findbugs.util.Strings;
34 import edu.umd.cs.findbugs.util.Util;
35 public class IsNullValueFrame extends Frame<IsNullValue> {
36 private IsNullConditionDecision decision;
37 private boolean trackValueNumbers;
38 private Map <ValueNumber, IsNullValue> knownValueMap;
39
40 public IsNullValueFrame(int numLocals, boolean trackValueNumbers) {
41 super(numLocals);
42 this.trackValueNumbers = trackValueNumbers;
43 if (trackValueNumbers) {
44 this.knownValueMap = new HashMap <ValueNumber, IsNullValue>();
45 }
46 }
47
48 public void cleanStaleKnowledge(ValueNumberFrame vnaFrameAfter) {
49 if (vnaFrameAfter.isTop() && !isTop()) throw new IllegalArgumentException ("VNA frame is top");
50 if (!trackValueNumbers) return;
51 for(Iterator <ValueNumber> i = knownValueMap.keySet().iterator(); i.hasNext(); ) {
52 ValueNumber v = i.next();
53 if (vnaFrameAfter.getLoad(v) == null) {
54 if (IsNullValueAnalysis.DEBUG)
55 System.out.println("PURGING " + v);
56 i.remove();
57 }
58 }
59
60 }
61 @Override
62 public void setTop() {
63 super.setTop();
64 if (trackValueNumbers) {
65 knownValueMap.clear();
66 }
67 decision = null;
68 }
69 public void toExceptionValues() {
70 for (int i = 0; i < getNumSlots(); ++i)
71 setValue(i, getValue(i).toExceptionValue());
72
73 if (trackValueNumbers) {
74 Map <ValueNumber, IsNullValue> replaceMap = new HashMap <ValueNumber, IsNullValue>();
75 for (Map.Entry <ValueNumber, IsNullValue> entry : knownValueMap.entrySet()) {
76 replaceMap.put(entry.getKey(), entry.getValue().toExceptionValue());
77 }
78 this.knownValueMap = replaceMap;
79 }
80 }
81
82 public void setDecision(@CheckForNull IsNullConditionDecision decision) {
83 this.decision = decision;
84 }
85
86 public @CheckForNull IsNullConditionDecision getDecision() {
87 return decision;
88 }
89
90 public void setKnownValue(@NonNull ValueNumber valueNumber, @NonNull IsNullValue knownValue) {
91 assert trackValueNumbers;
92 if (valueNumber == null || knownValue == null ) throw new NullPointerException ();
93 knownValueMap.put(valueNumber, knownValue);
94 if (IsNullValueAnalysis.DEBUG) {
95 System.out.println("Updated information for " + valueNumber);
96 System.out.println(" now " + this);
97 }
98 }
99 public void useNewValueNumberForLoad(ValueNumber oldValueNumber, ValueNumber newValueNumber) {
100 if (oldValueNumber == null || newValueNumber == null) throw new NullPointerException ();
101 if (newValueNumber.equals(oldValueNumber) || !trackValueNumbers) return;
102 IsNullValue isNullValue = knownValueMap.get(oldValueNumber);
103 if (isNullValue != null) {
104 knownValueMap.put(newValueNumber, isNullValue);
105 knownValueMap.remove(oldValueNumber);
106 }
107 }
108 public IsNullValue getKnownValue(ValueNumber valueNumber) {
109 assert trackValueNumbers;
110 return knownValueMap.get(valueNumber);
111 }
112
113 public Collection <ValueNumber> getKnownValues() {
114 if (trackValueNumbers) {
115 return knownValueMap.keySet();
116 } else {
117 return Collections.EMPTY_SET;
118 }
119 }
120
121 public Collection <Map.Entry <ValueNumber, IsNullValue>> getKnownValueMapEntrySet() {
122 if (trackValueNumbers) {
123 return knownValueMap.entrySet();
124 } else {
125 return Collections.EMPTY_SET;
126 }
127 }
128
129 public void mergeKnownValuesWith(IsNullValueFrame otherFrame) {
130 assert trackValueNumbers;
131 if (IsNullValueAnalysis.DEBUG) {
132 System.out.println("merge");
133 System.out.println(" " + this);
134 System.out.println(" with" + otherFrame);
135 }
136 Map <ValueNumber, IsNullValue> replaceMap = new HashMap <ValueNumber, IsNullValue>();
137 for (Map.Entry <ValueNumber, IsNullValue> entry : knownValueMap.entrySet()) {
138 IsNullValue otherKnownValue = otherFrame.knownValueMap.get(entry.getKey());
139 if (otherKnownValue == null) {
140 if (IsNullValueAnalysis.DEBUG) {
141 System.out.println("No match for " + entry.getKey());
142
143 }
144 continue;
145 }
146 IsNullValue mergedValue = IsNullValue.merge(entry.getValue(), otherKnownValue);
147 replaceMap.put(entry.getKey(), mergedValue);
148 if (IsNullValueAnalysis.DEBUG && !mergedValue.equals(entry.getValue())) {
149
150 System.out.println("Updated information for " + entry.getKey());
151 System.out.println(" was " + entry.getValue());
152 System.out.println(" merged value " + mergedValue);
153
154 }
155 }
156 knownValueMap.clear();
157 knownValueMap.putAll(replaceMap);
158 if (IsNullValueAnalysis.DEBUG) {
159 System.out.println("resulting in " + this);
160
161 }
162 }
163
164
167 @Override
168 public void copyFrom(Frame<IsNullValue> other) {
169 super.copyFrom(other);
170 decision = ((IsNullValueFrame)other).decision;
171 if (trackValueNumbers) {
172 knownValueMap = new HashMap <ValueNumber, IsNullValue>(((IsNullValueFrame)other).knownValueMap);
173 }
174 }
175
176 @Override
177 public boolean sameAs(Frame<IsNullValue> other) {
178 if (!(other instanceof IsNullValueFrame)) return false;
179 if (!super.sameAs(other)) return false;
180 IsNullValueFrame o2 = (IsNullValueFrame) other;
181 if (!Util.nullSafeEquals(decision, o2.decision)) return false;
182 if (trackValueNumbers && !Util.nullSafeEquals(knownValueMap, o2.knownValueMap)) return false;
183
184 return true;
185 }
186 @Override
187 public String toString() {
188 String result = super.toString();
189 if (decision != null) {
190 result = result + ", [decision=" + decision.toString() + "]";
191 }
192 if (knownValueMap != null) {
193 StringBuffer buf = new StringBuffer ();
195 buf.append("{");
196 boolean first = true;
197 for (Map.Entry <ValueNumber, IsNullValue> entry : knownValueMap.entrySet()) {
198 if (!first) {
199 buf.append(", ");
200 } else {
201 first = false;
202 }
203 buf.append(Strings.trimComma(entry.getKey().toString()));
204 buf.append("->");
205 buf.append(Strings.trimComma(entry.getValue().toString()));
206 }
207 buf.append("}");
208 result += ", [known=" + buf.toString() + "]";
209 }
210 return result;
211 }
212
213
217 public void downgradeOnControlSplit() {
218 final int numSlots = getNumSlots();
219 for (int i = 0; i < numSlots; ++i) {
220 IsNullValue value = getValue(i);
221 value = value.downgradeOnControlSplit();
222 setValue(i, value);
223 }
224
225 if (knownValueMap != null) {
226 for (Map.Entry <ValueNumber, IsNullValue> entry : knownValueMap.entrySet()) {
227 entry.setValue(entry.getValue().downgradeOnControlSplit());
228 }
229 }
230 }
231 }
232
233 |
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