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
|
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Tests properties of some string operations represented by intrinsics.
*/
public class Main {
static final String ABC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
static final String XYZ = "XYZ";
//
// Variant intrinsics remain in the loop, but invariant references are hoisted out of the loop.
//
/// CHECK-START: int Main.liveIndexOf() licm (before)
/// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOf loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOfAfter loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOf loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:{{B\d+}} outer_loop:none
//
/// CHECK-START: int Main.liveIndexOf() licm (after)
/// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOf loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOfAfter loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOf loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:none
static int liveIndexOf() {
int k = ABC.length() + XYZ.length(); // does LoadString before loops
for (char c = 'A'; c <= 'Z'; c++) {
k += ABC.indexOf(c);
}
for (char c = 'A'; c <= 'Z'; c++) {
k += ABC.indexOf(c, 4);
}
for (char c = 'A'; c <= 'Z'; c++) {
k += ABC.indexOf(XYZ);
}
for (char c = 'A'; c <= 'Z'; c++) {
k += ABC.indexOf(XYZ, 2);
}
return k;
}
//
// All dead intrinsics can be removed completely.
//
/// CHECK-START: int Main.deadIndexOf() dead_code_elimination$initial (before)
/// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOf loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOfAfter loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOf loop:{{B\d+}} outer_loop:none
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:{{B\d+}} outer_loop:none
//
/// CHECK-START: int Main.deadIndexOf() dead_code_elimination$initial (after)
/// CHECK-NOT: InvokeVirtual intrinsic:StringIndexOf
/// CHECK-NOT: InvokeVirtual intrinsic:StringIndexOfAfter
/// CHECK-NOT: InvokeVirtual intrinsic:StringStringIndexOf
/// CHECK-NOT: InvokeVirtual intrinsic:StringStringIndexOfAfter
static int deadIndexOf() {
int k = ABC.length() + XYZ.length(); // does LoadString before loops
for (char c = 'A'; c <= 'Z'; c++) {
int d = ABC.indexOf(c);
}
for (char c = 'A'; c <= 'Z'; c++) {
int d = ABC.indexOf(c, 4);
}
for (char c = 'A'; c <= 'Z'; c++) {
int d = ABC.indexOf(XYZ);
}
for (char c = 'A'; c <= 'Z'; c++) {
int d = ABC.indexOf(XYZ, 2);
}
return k;
}
//
// Explicit null check on receiver, implicit null check on argument prevents hoisting.
//
/// CHECK-START: int Main.indexOfExceptions(java.lang.String, java.lang.String) licm (after)
/// CHECK-DAG: <<String:l\d+>> NullCheck loop:<<Loop:B\d+>> outer_loop:none
/// CHECK-DAG: InvokeVirtual [<<String>>,{{l\d+}}] intrinsic:StringStringIndexOf loop:<<Loop>> outer_loop:none
static int indexOfExceptions(String s, String t) {
int k = 0;
for (char c = 'A'; c <= 'Z'; c++) {
k += s.indexOf(t);
}
return k;
}
public static void main(String[] args) {
expectEquals(1865, liveIndexOf());
expectEquals(29, deadIndexOf());
try {
indexOfExceptions(null, XYZ);
throw new Error("Expected: NPE");
} catch (NullPointerException e) {
}
try {
indexOfExceptions(ABC, null);
throw new Error("Expected: NPE");
} catch (NullPointerException e) {
}
expectEquals(598, indexOfExceptions(ABC, XYZ));
System.out.println("passed");
}
private static void expectEquals(int expected, int result) {
if (expected != result) {
throw new Error("Expected: " + expected + ", found: " + result);
}
}
}
|