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1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 public class Main {
18 
19   // Note #1: `javac` flips the conditions of If statements.
20   // Note #2: In the optimizing compiler, the first input of Phi is always
21   //          the fall-through path, i.e. the false branch.
22 
assertBoolEquals(boolean expected, boolean result)23   public static void assertBoolEquals(boolean expected, boolean result) {
24     if (expected != result) {
25       throw new Error("Expected: " + expected + ", found: " + result);
26     }
27   }
28 
assertIntEquals(int expected, int result)29   public static void assertIntEquals(int expected, int result) {
30     if (expected != result) {
31       throw new Error("Expected: " + expected + ", found: " + result);
32     }
33   }
34 
35   /*
36    * Elementary test negating a boolean. Verifies that blocks are merged and
37    * empty branches removed.
38    */
39 
40   /// CHECK-START: boolean Main.BooleanNot(boolean) select_generator (before)
41   /// CHECK-DAG:     <<Param:z\d+>>    ParameterValue
42   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
43   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
44   /// CHECK-DAG:                       If [<<Param>>]
45   /// CHECK-DAG:     <<Phi:i\d+>>      Phi [<<Const0>>,<<Const1>>]
46   /// CHECK-DAG:                       Return [<<Phi>>]
47 
48   /// CHECK-START: boolean Main.BooleanNot(boolean) select_generator (before)
49   /// CHECK:                           Goto
50   /// CHECK:                           Goto
51   /// CHECK:                           Goto
52   /// CHECK-NOT:                       Goto
53 
54   /// CHECK-START: boolean Main.BooleanNot(boolean) select_generator (after)
55   /// CHECK-DAG:     <<Param:z\d+>>    ParameterValue
56   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
57   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
58   /// CHECK-DAG:     <<NotParam:i\d+>> Select [<<Const1>>,<<Const0>>,<<Param>>]
59   /// CHECK-DAG:                       Return [<<NotParam>>]
60 
61   /// CHECK-START: boolean Main.BooleanNot(boolean) select_generator (after)
62   /// CHECK-NOT:                       If
63   /// CHECK-NOT:                       Phi
64 
65   /// CHECK-START: boolean Main.BooleanNot(boolean) select_generator (after)
66   /// CHECK:                           Goto
67   /// CHECK-NOT:                       Goto
68 
BooleanNot(boolean x)69   public static boolean BooleanNot(boolean x) {
70     return !x;
71   }
72 
73   /*
74    * Program which only delegates the condition, i.e. returns 1 when True
75    * and 0 when False.
76    */
77 
78   /// CHECK-START: boolean Main.GreaterThan(int, int) select_generator (before)
79   /// CHECK-DAG:     <<ParamX:i\d+>>   ParameterValue
80   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
81   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
82   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
83   /// CHECK-DAG:     <<Cond:z\d+>>     GreaterThan [<<ParamX>>,<<ParamY>>]
84   /// CHECK-DAG:                       If [<<Cond>>]
85   /// CHECK-DAG:     <<Phi:i\d+>>      Phi [<<Const0>>,<<Const1>>]
86   /// CHECK-DAG:                       Return [<<Phi>>]
87 
88   /// CHECK-START: boolean Main.GreaterThan(int, int) select_generator (after)
89   /// CHECK-DAG:     <<ParamX:i\d+>>   ParameterValue
90   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
91   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
92   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
93   /// CHECK-DAG:     <<Cond:z\d+>>     GreaterThan [<<ParamX>>,<<ParamY>>]
94   /// CHECK-DAG:     <<Select:i\d+>>   Select [<<Const0>>,<<Const1>>,<<Cond>>]
95   /// CHECK-DAG:                       Return [<<Select>>]
96 
GreaterThan(int x, int y)97   public static boolean GreaterThan(int x, int y) {
98     return (x <= y) ? false : true;
99   }
100 
101   /*
102    * Program which negates a condition, i.e. returns 0 when True
103    * and 1 when False.
104    */
105 
106   /// CHECK-START: boolean Main.LessThan(int, int) select_generator (before)
107   /// CHECK-DAG:     <<ParamX:i\d+>>   ParameterValue
108   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
109   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
110   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
111   /// CHECK-DAG:     <<Cond:z\d+>>     GreaterThanOrEqual [<<ParamX>>,<<ParamY>>]
112   /// CHECK-DAG:                       If [<<Cond>>]
113   /// CHECK-DAG:     <<Phi:i\d+>>      Phi [<<Const1>>,<<Const0>>]
114   /// CHECK-DAG:                       Return [<<Phi>>]
115 
116   /// CHECK-START: boolean Main.LessThan(int, int) select_generator (after)
117   /// CHECK-DAG:     <<ParamX:i\d+>>   ParameterValue
118   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
119   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
120   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
121   /// CHECK-DAG:     <<Cond:z\d+>>     GreaterThanOrEqual [<<ParamX>>,<<ParamY>>]
122   /// CHECK-DAG:     <<Select:i\d+>>   Select [<<Const1>>,<<Const0>>,<<Cond>>]
123   /// CHECK-DAG:                       Return [<<Select>>]
124 
LessThan(int x, int y)125   public static boolean LessThan(int x, int y) {
126     return (x < y) ? true : false;
127   }
128 
129   /*
130    * Program which further uses negated conditions.
131    * Note that Phis are discovered retrospectively.
132    */
133 
134   /// CHECK-START: boolean Main.ValuesOrdered(int, int, int) select_generator (before)
135   /// CHECK-DAG:     <<ParamX:i\d+>>   ParameterValue
136   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
137   /// CHECK-DAG:     <<ParamZ:i\d+>>   ParameterValue
138   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
139   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
140   /// CHECK-DAG:     <<CondXY:z\d+>>   GreaterThan [<<ParamX>>,<<ParamY>>]
141   /// CHECK-DAG:                       If [<<CondXY>>]
142   /// CHECK-DAG:     <<CondYZ:z\d+>>   GreaterThan [<<ParamY>>,<<ParamZ>>]
143   /// CHECK-DAG:                       If [<<CondYZ>>]
144   /// CHECK-DAG:     <<CondXYZ:z\d+>>  NotEqual [<<PhiXY:i\d+>>,<<PhiYZ:i\d+>>]
145   /// CHECK-DAG:                       If [<<CondXYZ>>]
146   /// CHECK-DAG:                       Return [<<PhiXYZ:i\d+>>]
147   /// CHECK-DAG:     <<PhiXY>>         Phi [<<Const1>>,<<Const0>>]
148   /// CHECK-DAG:     <<PhiYZ>>         Phi [<<Const1>>,<<Const0>>]
149   /// CHECK-DAG:     <<PhiXYZ>>        Phi [<<Const1>>,<<Const0>>]
150 
151   /// CHECK-START: boolean Main.ValuesOrdered(int, int, int) select_generator (after)
152   /// CHECK-DAG:     <<ParamX:i\d+>>   ParameterValue
153   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
154   /// CHECK-DAG:     <<ParamZ:i\d+>>   ParameterValue
155   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
156   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
157   /// CHECK-DAG:     <<CmpXY:z\d+>>    GreaterThan [<<ParamX>>,<<ParamY>>]
158   /// CHECK-DAG:     <<SelXY:i\d+>>    Select [<<Const1>>,<<Const0>>,<<CmpXY>>]
159   /// CHECK-DAG:     <<CmpYZ:z\d+>>    GreaterThan [<<ParamY>>,<<ParamZ>>]
160   /// CHECK-DAG:     <<SelYZ:i\d+>>    Select [<<Const1>>,<<Const0>>,<<CmpYZ>>]
161   /// CHECK-DAG:     <<CmpXYZ:z\d+>>   NotEqual [<<SelXY>>,<<SelYZ>>]
162   /// CHECK-DAG:     <<SelXYZ:i\d+>>   Select [<<Const1>>,<<Const0>>,<<CmpXYZ>>]
163   /// CHECK-DAG:                       Return [<<SelXYZ>>]
164 
ValuesOrdered(int x, int y, int z)165   public static boolean ValuesOrdered(int x, int y, int z) {
166     return (x <= y) == (y <= z);
167   }
168 
169   /// CHECK-START: int Main.NegatedCondition(boolean) select_generator (before)
170   /// CHECK-DAG:     <<Param:z\d+>>    ParameterValue
171   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
172   /// CHECK-DAG:     <<Const43:i\d+>>  IntConstant 43
173   /// CHECK-DAG:                       If [<<Param>>]
174   /// CHECK-DAG:     <<Phi:i\d+>>      Phi [<<Const42>>,<<Const43>>]
175   /// CHECK-DAG:                       Return [<<Phi>>]
176 
177   /// CHECK-START: int Main.NegatedCondition(boolean) select_generator (after)
178   /// CHECK-DAG:     <<Param:z\d+>>    ParameterValue
179   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
180   /// CHECK-DAG:     <<Const43:i\d+>>  IntConstant 43
181   /// CHECK-DAG:     <<Select:i\d+>>   Select [<<Const43>>,<<Const42>>,<<Param>>]
182   /// CHECK-DAG:                       Return [<<Select>>]
183 
184   /// CHECK-START: int Main.NegatedCondition(boolean) select_generator (after)
185   /// CHECK-NOT:                       BooleanNot
186 
NegatedCondition(boolean x)187   public static int NegatedCondition(boolean x) {
188     return (x != false) ? 42 : 43;
189   }
190 
191   /// CHECK-START: int Main.SimpleTrueBlock(boolean, int) select_generator (after)
192   /// CHECK-DAG:     <<ParamX:z\d+>>   ParameterValue
193   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
194   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
195   /// CHECK-DAG:     <<Const43:i\d+>>  IntConstant 43
196   /// CHECK-DAG:     <<Add:i\d+>>      Add [<<ParamY>>,<<Const42>>]
197   /// CHECK-DAG:     <<Select:i\d+>>   Select [<<Const43>>,<<Add>>,<<ParamX>>]
198   /// CHECK-DAG:                       Return [<<Select>>]
199 
200   /// CHECK-START: int Main.SimpleTrueBlock(boolean, int) select_generator (after)
201   /// CHECK-NOT:     If
202 
SimpleTrueBlock(boolean x, int y)203   public static int SimpleTrueBlock(boolean x, int y) {
204     return x ? y + 42 : 43;
205   }
206 
207   /// CHECK-START: int Main.SimpleFalseBlock(boolean, int) select_generator (after)
208   /// CHECK-DAG:     <<ParamX:z\d+>>   ParameterValue
209   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
210   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
211   /// CHECK-DAG:     <<Const43:i\d+>>  IntConstant 43
212   /// CHECK-DAG:     <<Add:i\d+>>      Add [<<ParamY>>,<<Const43>>]
213   /// CHECK-DAG:     <<Select:i\d+>>   Select [<<Add>>,<<Const42>>,<<ParamX>>]
214   /// CHECK-DAG:                       Return [<<Select>>]
215 
216   /// CHECK-START: int Main.SimpleFalseBlock(boolean, int) select_generator (after)
217   /// CHECK-NOT:     If
218 
SimpleFalseBlock(boolean x, int y)219   public static int SimpleFalseBlock(boolean x, int y) {
220     return x ? 42 : y + 43;
221   }
222 
223   /// CHECK-START: int Main.SimpleBothBlocks(boolean, int, int) select_generator (after)
224   /// CHECK-DAG:     <<ParamX:z\d+>>   ParameterValue
225   /// CHECK-DAG:     <<ParamY:i\d+>>   ParameterValue
226   /// CHECK-DAG:     <<ParamZ:i\d+>>   ParameterValue
227   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
228   /// CHECK-DAG:     <<Const43:i\d+>>  IntConstant 43
229   /// CHECK-DAG:     <<AddTrue:i\d+>>  Add [<<ParamY>>,<<Const42>>]
230   /// CHECK-DAG:     <<AddFalse:i\d+>> Add [<<ParamZ>>,<<Const43>>]
231   /// CHECK-DAG:     <<Select:i\d+>>   Select [<<AddFalse>>,<<AddTrue>>,<<ParamX>>]
232   /// CHECK-DAG:                       Return [<<Select>>]
233 
234   /// CHECK-START: int Main.SimpleBothBlocks(boolean, int, int) select_generator (after)
235   /// CHECK-NOT:     If
236 
SimpleBothBlocks(boolean x, int y, int z)237   public static int SimpleBothBlocks(boolean x, int y, int z) {
238     return x ? y + 42 : z + 43;
239   }
240 
241   /// CHECK-START: int Main.ThreeBlocks(boolean, boolean) select_generator (after)
242   /// CHECK-DAG:     <<ParamX:z\d+>>    ParameterValue
243   /// CHECK-DAG:     <<ParamY:z\d+>>    ParameterValue
244   /// CHECK-DAG:     <<Const1:i\d+>>    IntConstant 1
245   /// CHECK-DAG:     <<Const2:i\d+>>    IntConstant 2
246   /// CHECK-DAG:     <<Const3:i\d+>>    IntConstant 3
247   /// CHECK-DAG:     <<Select23:i\d+>>  Select [<<Const3>>,<<Const2>>,<<ParamY>>]
248   /// CHECK-DAG:     <<Select123:i\d+>> Select [<<Select23>>,<<Const1>>,<<ParamX>>]
249   /// CHECK-DAG:                        Return [<<Select123>>]
250 
ThreeBlocks(boolean x, boolean y)251   public static int ThreeBlocks(boolean x, boolean y) {
252     return x ? 1 : (y ? 2 : 3);
253   }
254 
255   /// CHECK-START: int Main.MultiplePhis() select_generator (before)
256   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
257   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
258   /// CHECK-DAG:     <<Const13:i\d+>>  IntConstant 13
259   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
260   /// CHECK-DAG:     <<PhiX:i\d+>>     Phi [<<Const0>>,<<Const13>>,<<Const42>>]
261   /// CHECK-DAG:     <<PhiY:i\d+>>     Phi [<<Const1>>,<<Add:i\d+>>,<<Add>>]
262   /// CHECK-DAG:     <<Add>>           Add [<<PhiY>>,<<Const1>>]
263   /// CHECK-DAG:     <<Cond:z\d+>>     LessThanOrEqual [<<Add>>,<<Const1>>]
264   /// CHECK-DAG:                       If [<<Cond>>]
265   /// CHECK-DAG:                       Return [<<PhiX>>]
266 
267   /// CHECK-START: int Main.MultiplePhis() select_generator (after)
268   /// CHECK-DAG:     <<Const0:i\d+>>   IntConstant 0
269   /// CHECK-DAG:     <<Const1:i\d+>>   IntConstant 1
270   /// CHECK-DAG:     <<Const13:i\d+>>  IntConstant 13
271   /// CHECK-DAG:     <<Const42:i\d+>>  IntConstant 42
272   /// CHECK-DAG:     <<PhiX:i\d+>>     Phi [<<Const0>>,<<Select:i\d+>>]
273   /// CHECK-DAG:     <<PhiY:i\d+>>     Phi [<<Const1>>,<<Add:i\d+>>]
274   /// CHECK-DAG:     <<Add>>           Add [<<PhiY>>,<<Const1>>]
275   /// CHECK-DAG:     <<Cond:z\d+>>     LessThanOrEqual [<<Add>>,<<Const1>>]
276   /// CHECK-DAG:     <<Select>>        Select [<<Const13>>,<<Const42>>,<<Cond>>]
277   /// CHECK-DAG:                       Return [<<PhiX>>]
278 
MultiplePhis()279   public static int MultiplePhis() {
280     int x = 0;
281     int y = 1;
282     while (y++ < 10) {
283       if (y > 1) {
284         x = 13;
285         continue;
286       } else {
287         x = 42;
288         continue;
289       }
290     }
291     return x;
292   }
293 
294   /// CHECK-START: int Main.TrueBlockWithTooManyInstructions(boolean) select_generator (before)
295   /// CHECK-DAG:     <<This:l\d+>>    ParameterValue
296   /// CHECK-DAG:     <<Cond:z\d+>>    ParameterValue
297   /// CHECK-DAG:     <<Const2:i\d+>>  IntConstant 2
298   /// CHECK-DAG:     <<Const43:i\d+>> IntConstant 43
299   /// CHECK-DAG:                      If [<<Cond>>]
300   /// CHECK-DAG:     <<Iget:i\d+>>    InstanceFieldGet [<<This>>]
301   /// CHECK-DAG:     <<Add:i\d+>>     Add [<<Iget>>,<<Const2>>]
302   /// CHECK-DAG:                      Phi [<<Add>>,<<Const43>>]
303 
304   /// CHECK-START: int Main.TrueBlockWithTooManyInstructions(boolean) select_generator (after)
305   /// CHECK-NOT:     Select
306 
TrueBlockWithTooManyInstructions(boolean x)307   public int TrueBlockWithTooManyInstructions(boolean x) {
308     return x ? (read_field + 2) : 43;
309   }
310 
311   /// CHECK-START: int Main.FalseBlockWithTooManyInstructions(boolean) select_generator (before)
312   /// CHECK-DAG:     <<This:l\d+>>    ParameterValue
313   /// CHECK-DAG:     <<Cond:z\d+>>    ParameterValue
314   /// CHECK-DAG:     <<Const3:i\d+>>  IntConstant 3
315   /// CHECK-DAG:     <<Const42:i\d+>> IntConstant 42
316   /// CHECK-DAG:                      If [<<Cond>>]
317   /// CHECK-DAG:     <<Iget:i\d+>>    InstanceFieldGet [<<This>>]
318   /// CHECK-DAG:     <<Add:i\d+>>     Add [<<Iget>>,<<Const3>>]
319   /// CHECK-DAG:                      Phi [<<Const42>>,<<Add>>]
320 
321   /// CHECK-START: int Main.FalseBlockWithTooManyInstructions(boolean) select_generator (after)
322   /// CHECK-NOT:     Select
323 
FalseBlockWithTooManyInstructions(boolean x)324   public int FalseBlockWithTooManyInstructions(boolean x) {
325     return x ? 42 : (read_field + 3);
326   }
327 
328   /// CHECK-START: int Main.TrueBlockWithSideEffects(boolean) select_generator (before)
329   /// CHECK-DAG:     <<This:l\d+>>    ParameterValue
330   /// CHECK-DAG:     <<Cond:z\d+>>    ParameterValue
331   /// CHECK-DAG:     <<Const42:i\d+>> IntConstant 42
332   /// CHECK-DAG:     <<Const43:i\d+>> IntConstant 43
333   /// CHECK-DAG:                      If [<<Cond>>]
334   /// CHECK-DAG:                      InstanceFieldSet [<<This>>,<<Const42>>]
335   /// CHECK-DAG:                      Phi [<<Const42>>,<<Const43>>]
336 
337   /// CHECK-START: int Main.TrueBlockWithSideEffects(boolean) select_generator (after)
338   /// CHECK-NOT:     Select
339 
TrueBlockWithSideEffects(boolean x)340   public int TrueBlockWithSideEffects(boolean x) {
341     return x ? (write_field = 42) : 43;
342   }
343 
344   /// CHECK-START: int Main.FalseBlockWithSideEffects(boolean) select_generator (before)
345   /// CHECK-DAG:     <<This:l\d+>>    ParameterValue
346   /// CHECK-DAG:     <<Cond:z\d+>>    ParameterValue
347   /// CHECK-DAG:     <<Const42:i\d+>> IntConstant 42
348   /// CHECK-DAG:     <<Const43:i\d+>> IntConstant 43
349   /// CHECK-DAG:                      If [<<Cond>>]
350   /// CHECK-DAG:                      InstanceFieldSet [<<This>>,<<Const43>>]
351   /// CHECK-DAG:                      Phi [<<Const42>>,<<Const43>>]
352 
353   /// CHECK-START: int Main.FalseBlockWithSideEffects(boolean) select_generator (after)
354   /// CHECK-NOT:     Select
355 
FalseBlockWithSideEffects(boolean x)356   public int FalseBlockWithSideEffects(boolean x) {
357     return x ? 42 : (write_field = 43);
358   }
359 
main(String[] args)360   public static void main(String[] args) {
361     assertBoolEquals(false, BooleanNot(true));
362     assertBoolEquals(true, BooleanNot(false));
363     assertBoolEquals(true, GreaterThan(10, 5));
364     assertBoolEquals(false, GreaterThan(10, 10));
365     assertBoolEquals(false, GreaterThan(5, 10));
366     assertBoolEquals(true, LessThan(5, 10));
367     assertBoolEquals(false, LessThan(10, 10));
368     assertBoolEquals(false, LessThan(10, 5));
369     assertBoolEquals(true, ValuesOrdered(1, 3, 5));
370     assertBoolEquals(true, ValuesOrdered(5, 3, 1));
371     assertBoolEquals(false, ValuesOrdered(1, 3, 2));
372     assertBoolEquals(false, ValuesOrdered(2, 3, 1));
373     assertBoolEquals(true, ValuesOrdered(3, 3, 3));
374     assertBoolEquals(true, ValuesOrdered(3, 3, 5));
375     assertBoolEquals(false, ValuesOrdered(5, 5, 3));
376     assertIntEquals(42, NegatedCondition(true));
377     assertIntEquals(43, NegatedCondition(false));
378     assertIntEquals(46, SimpleTrueBlock(true, 4));
379     assertIntEquals(43, SimpleTrueBlock(false, 4));
380     assertIntEquals(42, SimpleFalseBlock(true, 7));
381     assertIntEquals(50, SimpleFalseBlock(false, 7));
382     assertIntEquals(48, SimpleBothBlocks(true, 6, 2));
383     assertIntEquals(45, SimpleBothBlocks(false, 6, 2));
384     assertIntEquals(1, ThreeBlocks(true, true));
385     assertIntEquals(1, ThreeBlocks(true, false));
386     assertIntEquals(2, ThreeBlocks(false, true));
387     assertIntEquals(3, ThreeBlocks(false, false));
388     assertIntEquals(13, MultiplePhis());
389 
390     Main m = new Main();
391     assertIntEquals(42, m.TrueBlockWithTooManyInstructions(true));
392     assertIntEquals(43, m.TrueBlockWithTooManyInstructions(false));
393     assertIntEquals(42, m.FalseBlockWithTooManyInstructions(true));
394     assertIntEquals(43, m.FalseBlockWithTooManyInstructions(false));
395     assertIntEquals(42, m.TrueBlockWithSideEffects(true));
396     assertIntEquals(43, m.TrueBlockWithSideEffects(false));
397     assertIntEquals(42, m.FalseBlockWithSideEffects(true));
398     assertIntEquals(43, m.FalseBlockWithSideEffects(false));
399   }
400 
401   // These need to be instance fields so as to not generate a LoadClass for iget/iput.
402   public int read_field = 40;
403   public int write_field = 42;
404 }
405