1 /*
2 * Copyright (c) 2014 Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23 package org.openjdk.bench.vm.compiler;
24
25 import org.openjdk.jmh.annotations.Benchmark;
26 import org.openjdk.jmh.annotations.BenchmarkMode;
27 import org.openjdk.jmh.annotations.Mode;
28 import org.openjdk.jmh.annotations.OutputTimeUnit;
29 import org.openjdk.jmh.annotations.Param;
30 import org.openjdk.jmh.annotations.Scope;
31 import org.openjdk.jmh.annotations.State;
32
33 import java.util.concurrent.TimeUnit;
34
35 /**
36 * Test spill code generation.
37 */
38 @BenchmarkMode(Mode.AverageTime)
39 @OutputTimeUnit(TimeUnit.NANOSECONDS)
40 @State(Scope.Thread)
41 public class SpillCode {
42
43 @Param("10")
44 private int iterations;
45
46 private int dummy;
47
48 private int doSomeCalcsInLargeBlockWithInts(int start, int iter) {
49
50 int a1, a2, a3, a4;
51 int b1, b2, b3, b4;
52 int c1, c2, c3, c4;
53 int d1, d2, d3, d4;
54 int e1, e2, e3, e4;
55 int f1, f2, f3, f4;
56 int g1, g2, g3, g4;
57 int h1, h2, h3, h4;
58
59 // a1 = b1 = c1 = d1 = e1 = f1 = g1 = h1 = (start % 2);
60 a2 = b2 = c2 = d2 = e2 = f2 = g2 = h2 = (start % 2);
61 a3 = b3 = c3 = d3 = e3 = f3 = g3 = h3 = (start % 4);
62 a4 = b4 = c4 = d4 = e4 = f4 = g4 = h4 = (start % 8);
63
64 for (int i = 0; i < iter; i++) {
65
66 // for each section, only x1 needs to survive.
67
68 // a1 = a2 = a3 = a4 = (start + a1) % 2;
69 a1 = start;
70 a1 = a1 + a2 + a3 + a4;
71 a2 = a1 + a2 + a3 + a4;
72 a3 = a1 + a2 + a3 + a4;
73 a4 = a1 + a2 + a3 + a4;
74 a1 = a1 + a2 + a3 + a4;
75 a2 = a1 + a2 + a3 + a4;
76 a3 = a1 + a2 + a3 + a4;
77 a4 = a1 + a2 + a3 + a4;
78 a1 = a1 + a2 + a3 + a4;
79 a2 = a1 + a2 + a3 + a4;
80 a3 = a1 + a2 + a3 + a4;
81 a4 = a1 + a2 + a3 + a4;
82
83 // b1 = b2 = b3 = b4 = (a4 + b1) % 2;
84 b1 = a4;
85 b1 = b1 + b2 + b3 + b4;
86 b2 = b1 + b2 + b3 + b4;
87 b3 = b1 + b2 + b3 + b4;
88 b4 = b1 + b2 + b3 + b4;
89 b1 = b1 + b2 + b3 + b4;
90 b2 = b1 + b2 + b3 + b4;
91 b3 = b1 + b2 + b3 + b4;
92 b4 = b1 + b2 + b3 + b4;
93 b1 = b1 + b2 + b3 + b4;
94 b2 = b1 + b2 + b3 + b4;
95 b3 = b1 + b2 + b3 + b4;
96 b4 = b1 + b2 + b3 + b4;
97
98 // c1 = c2 = c3 = c4 = (b4 + c1) % 2;
99 c1 = b4;
100 c1 = c1 + c2 + c3 + c4;
101 c2 = c1 + c2 + c3 + c4;
102 c3 = c1 + c2 + c3 + c4;
103 c4 = c1 + c2 + c3 + c4;
104 c1 = c1 + c2 + c3 + c4;
105 c2 = c1 + c2 + c3 + c4;
106 c3 = c1 + c2 + c3 + c4;
107 c4 = c1 + c2 + c3 + c4;
108 c1 = c1 + c2 + c3 + c4;
109 c2 = c1 + c2 + c3 + c4;
110 c3 = c1 + c2 + c3 + c4;
111 c4 = c1 + c2 + c3 + c4;
112
113 // d1 = d2 = d3 = d4 = (c4 + d1) % 2;
114 d1 = c4;
115 d1 = d1 + d2 + d3 + d4;
116 d2 = d1 + d2 + d3 + d4;
117 d3 = d1 + d2 + d3 + d4;
118 d4 = d1 + d2 + d3 + d4;
119 d1 = d1 + d2 + d3 + d4;
120 d2 = d1 + d2 + d3 + d4;
121 d3 = d1 + d2 + d3 + d4;
122 d4 = d1 + d2 + d3 + d4;
123 d1 = d1 + d2 + d3 + d4;
124 d2 = d1 + d2 + d3 + d4;
125 d3 = d1 + d2 + d3 + d4;
126 d4 = d1 + d2 + d3 + d4;
127
128 // e1 = e2 = e3 = e4 = (d4 + e1) % 2;
129 e1 = d4;
130 e1 = e1 + e2 + e3 + e4;
131 e2 = e1 + e2 + e3 + e4;
132 e3 = e1 + e2 + e3 + e4;
133 e4 = e1 + e2 + e3 + e4;
134 e1 = e1 + e2 + e3 + e4;
135 e2 = e1 + e2 + e3 + e4;
136 e3 = e1 + e2 + e3 + e4;
137 e4 = e1 + e2 + e3 + e4;
138 e1 = e1 + e2 + e3 + e4;
139 e2 = e1 + e2 + e3 + e4;
140 e3 = e1 + e2 + e3 + e4;
141 e4 = e1 + e2 + e3 + e4;
142
143 // f1 = f2 = f3 = f4 = (e4 + f1) % 2;
144 f1 = e4;
145 f1 = f1 + f2 + f3 + f4;
146 f2 = f1 + f2 + f3 + f4;
147 f3 = f1 + f2 + f3 + f4;
148 f4 = f1 + f2 + f3 + f4;
149 f1 = f1 + f2 + f3 + f4;
150 f2 = f1 + f2 + f3 + f4;
151 f3 = f1 + f2 + f3 + f4;
152 f4 = f1 + f2 + f3 + f4;
153 f1 = f1 + f2 + f3 + f4;
154 f2 = f1 + f2 + f3 + f4;
155 f3 = f1 + f2 + f3 + f4;
156 f4 = f1 + f2 + f3 + f4;
157
158 // g1 = g2 = g3 = g4 = (f4 + g1) % 2;
159 g1 = f4;
160 g1 = g1 + g2 + g3 + g4;
161 g2 = g1 + g2 + g3 + g4;
162 g3 = g1 + g2 + g3 + g4;
163 g4 = g1 + g2 + g3 + g4;
164 g1 = g1 + g2 + g3 + g4;
165 g2 = g1 + g2 + g3 + g4;
166 g3 = g1 + g2 + g3 + g4;
167 g4 = g1 + g2 + g3 + g4;
168 g1 = g1 + g2 + g3 + g4;
169 g2 = g1 + g2 + g3 + g4;
170 g3 = g1 + g2 + g3 + g4;
171 g4 = g1 + g2 + g3 + g4;
172
173 // h1 = h2 = h3 = h4 = (g4 + h1) % 2;
174 h1 = g4;
175 h1 = h1 + h2 + h3 + h4;
176 h2 = h1 + h2 + h3 + h4;
177 h3 = h1 + h2 + h3 + h4;
178 h4 = h1 + h2 + h3 + h4;
179 h1 = h1 + h2 + h3 + h4;
180 h2 = h1 + h2 + h3 + h4;
181 h3 = h1 + h2 + h3 + h4;
182 h4 = h1 + h2 + h3 + h4;
183 h1 = h1 + h2 + h3 + h4;
184 h2 = h1 + h2 + h3 + h4;
185 h3 = h1 + h2 + h3 + h4;
186 h4 = h1 + h2 + h3 + h4;
187
188 start = h4;
189 }
190
191 return start;
192 }
193
194 /**
195 * The test runs a loop with many local variables. The issue it reproduces is that if handled wrong, too many variables
196 * are put on and referenced on stack. The number of iterations is taken from global variable, to prevent static loop
197 * unrolling. Many of the variables used in the larger loop are local inside the block and do dnot need to survive from
198 * one iteration to the next.
199 */
200 @Benchmark
201 public int testSpillForManyInts() throws Exception {
202 return doSomeCalcsInLargeBlockWithInts(dummy, iterations);
203 }
204 }