1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
/*
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/**
* @test
* @key stress randomness
* @bug 8299259
* @requires vm.compiler2.enabled
* @summary Test various cases of divisions/modulo which should not be split through iv phis.
* @run main/othervm -Xbatch -XX:+UnlockDiagnosticVMOptions -XX:LoopUnrollLimit=0 -XX:+StressGCM
* -XX:CompileCommand=compileonly,compiler.splitif.TestSplitDivisionThroughPhi::*
* compiler.splitif.TestSplitDivisionThroughPhi
*/
package compiler.splitif;
public class TestSplitDivisionThroughPhi {
static int iFld;
static long lFld;
static boolean flag;
public static void main(String[] strArr) {
for (int i = 0; i < 5000; i++) {
testPushDivIThruPhi();
testPushDivIThruPhiInChain();
testPushModIThruPhi();
testPushModIThruPhiInChain();
testPushDivLThruPhi();
testPushDivLThruPhiInChain();
testPushModLThruPhi();
testPushModLThruPhiInChain();
}
}
// Already fixed by JDK-8248552.
static void testPushDivIThruPhi() {
for (int i = 10; i > 1; i -= 2) {
// The Div node is only split in later loop opts phase because the zero divisor check is only removed
// in IGVN after the first loop opts phase.
//
// iv phi i type: [2..10]
// When splitting the DivI through the iv phi, it ends up on the back edge with the trip count decrement
// as input which has type [0..8]. We end up executing a division by zero on the last iteration because
// the DivI it is not pinned to the loop exit test and can freely float above the loop exit check.
iFld = 10 / i;
}
}
// Same as above but with an additional Mul node between the iv phi and the Div node. Both nodes are split through
// the iv phi in one pass of Split If.
static void testPushDivIThruPhiInChain() {
for (int i = 10; i > 1; i -= 2) {
// Empty one iteration loop which is only removed after split if in first loop opts phase. This prevents
// that the Mul node is already split through the iv phi while the Div node cannot be split yet due to
// the zero divisor check which can only be removed in the IGVN after the first loop opts pass.
for (int j = 0; j < 1; j++) {
}
iFld = 10 / (i * 100);
}
}
// Already fixed by JDK-8248552.
static void testPushModIThruPhi() {
for (int i = 10; i > 1; i -= 2) {
iFld = 10 / i;
}
}
// Same as above but with ModI.
static void testPushModIThruPhiInChain() {
for (int i = 10; i > 1; i -= 2) {
for (int j = 0; j < 1; j++) {
}
iFld = 10 / (i * 100);
}
}
// Long cases only trigger since JDK-8256655.
// Same as above but with DivL.
static void testPushDivLThruPhi() {
for (long i = 10; i > 1; i -= 2) {
lFld = 10L / i;
// Loop that is not removed such that we do not transform the outer LongCountedLoop (only done if innermost)
for (int j = 0; j < 10; j++) {
flag = !flag;
}
}
}
// Same as above but with DivL.
static void testPushDivLThruPhiInChain() {
for (long i = 10; i > 1; i -= 2) {
for (int j = 0; j < 1; j++) {
}
lFld = 10L / (i * 100L);
for (int j = 0; j < 10; j++) {
flag = !flag;
}
}
}
// Same as above but with ModL
static void testPushModLThruPhi() {
for (long i = 10; i > 1; i -= 2) {
lFld = 10L % i;
for (int j = 0; j < 10; j++) {
flag = !flag;
}
}
}
// Same as above but with ModL
static void testPushModLThruPhiInChain() {
for (long i = 10; i > 1; i -= 2) {
for (int j = 0; j < 1; j++) {
}
lFld = 10L % (i * 100L);
for (int j = 0; j < 10; j++) {
flag = !flag;
}
}
}
}
|
