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/*
* 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.
*/
import java.lang.reflect.Method;
/**
* 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;
}
//
// Allows combining of returned "this". Also ensures that similar looking append() calls
// are not combined somehow through returned result.
//
/// CHECK-START: int Main.bufferLen2() instruction_simplifier (before)
/// CHECK-DAG: <<New:l\d+>> NewInstance
/// CHECK-DAG: <<String1:l\d+>> LoadString
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<New>>,<<String1>>] intrinsic:StringBufferAppend
/// CHECK-DAG: <<String2:l\d+>> LoadString
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [{{l\d+}},<<String2>>] intrinsic:StringBufferAppend
/// CHECK-DAG: InvokeVirtual [{{l\d+}}] intrinsic:StringBufferLength
//
/// CHECK-START: int Main.bufferLen2() instruction_simplifier (after)
/// CHECK-DAG: <<New:l\d+>> NewInstance
/// CHECK-DAG: <<String1:l\d+>> LoadString
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<New>>,<<String1>>] intrinsic:StringBufferAppend
/// CHECK-DAG: <<String2:l\d+>> LoadString
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [<<New>>,<<String2>>] intrinsic:StringBufferAppend
/// CHECK-DAG: InvokeVirtual [<<New>>] intrinsic:StringBufferLength
static int bufferLen2() {
StringBuffer s = new StringBuffer();
return s.append("x").append("y").length();
}
static int bufferLen2Smali() throws Exception {
Class<?> c = Class.forName("Smali");
Method m = c.getMethod("bufferLen2");
return (Integer) m.invoke(null);
}
//
// Allows combining of returned "this". Also ensures that similar looking append() calls
// are not combined somehow through returned result.
//
/// CHECK-START: int Main.builderLen2() instruction_simplifier (before)
/// CHECK-DAG: <<New:l\d+>> NewInstance
/// CHECK-DAG: <<String1:l\d+>> LoadString
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<New>>,<<String1>>] intrinsic:StringBuilderAppendString
/// CHECK-DAG: <<String2:l\d+>> LoadString
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [{{l\d+}},<<String2>>] intrinsic:StringBuilderAppendString
/// CHECK-DAG: InvokeVirtual [{{l\d+}}] intrinsic:StringBuilderLength
//
/// CHECK-START: int Main.builderLen2() instruction_simplifier (after)
/// CHECK-DAG: <<New:l\d+>> NewInstance
/// CHECK-DAG: <<String1:l\d+>> LoadString
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<New>>,<<String1>>] intrinsic:StringBuilderAppendString
/// CHECK-DAG: <<String2:l\d+>> LoadString
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [<<New>>,<<String2>>] intrinsic:StringBuilderAppendString
/// CHECK-DAG: InvokeVirtual [<<New>>] intrinsic:StringBuilderLength
static int builderLen2() {
StringBuilder s = new StringBuilder();
return s.append("x").append("y").length();
}
static int builderLen2Smali() throws Exception {
Class<?> c = Class.forName("Smali");
Method m = c.getMethod("builderLen2");
return (Integer) m.invoke(null);
}
//
// Similar situation in a loop.
//
/// CHECK-START: int Main.bufferLoopAppender() instruction_simplifier (before)
/// CHECK-DAG: <<New:l\d+>> NewInstance loop:none
/// CHECK-DAG: <<String1:l\d+>> LoadString loop:<<Loop:B\d+>>
/// CHECK-DAG: <<Null1:l\d+>> NullCheck [<<New>>] loop:<<Loop>>
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<Null1>>,<<String1>>] intrinsic:StringBufferAppend loop:<<Loop>>
/// CHECK-DAG: <<String2:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [{{l\d+}},<<String2>>] intrinsic:StringBufferAppend loop:<<Loop>>
/// CHECK-DAG: <<String3:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append3:l\d+>> InvokeVirtual [{{l\d+}},<<String3>>] intrinsic:StringBufferAppend loop:<<Loop>>
/// CHECK-DAG: InvokeVirtual [{{l\d+}}] intrinsic:StringBufferLength loop:none
//
/// CHECK-START: int Main.bufferLoopAppender() instruction_simplifier (after)
/// CHECK-DAG: <<New:l\d+>> NewInstance loop:none
/// CHECK-DAG: <<String1:l\d+>> LoadString loop:<<Loop:B\d+>>
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<New>>,<<String1>>] intrinsic:StringBufferAppend loop:<<Loop>>
/// CHECK-DAG: <<String2:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [<<New>>,<<String2>>] intrinsic:StringBufferAppend loop:<<Loop>>
/// CHECK-DAG: <<String3:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append3:l\d+>> InvokeVirtual [<<New>>,<<String3>>] intrinsic:StringBufferAppend loop:<<Loop>>
/// CHECK-DAG: InvokeVirtual [<<New>>] intrinsic:StringBufferLength loop:none
static int bufferLoopAppender() {
StringBuffer b = new StringBuffer();
for (int i = 0; i < 10; i++) {
b.append("x").append("y").append("z");
}
return b.length();
}
static int bufferLoopAppenderSmali() throws Exception {
Class<?> c = Class.forName("Smali");
Method m = c.getMethod("bufferLoopAppender");
return (Integer) m.invoke(null);
}
//
// Similar situation in a loop.
//
/// CHECK-START: int Main.builderLoopAppender() instruction_simplifier (before)
/// CHECK-DAG: <<New:l\d+>> NewInstance loop:none
/// CHECK-DAG: <<String1:l\d+>> LoadString loop:<<Loop:B\d+>>
/// CHECK-DAG: <<Null1:l\d+>> NullCheck [<<New>>] loop:<<Loop>>
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<Null1>>,<<String1>>] intrinsic:StringBuilderAppendString loop:<<Loop>>
/// CHECK-DAG: <<String2:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [{{l\d+}},<<String2>>] intrinsic:StringBuilderAppendString loop:<<Loop>>
/// CHECK-DAG: <<String3:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append3:l\d+>> InvokeVirtual [{{l\d+}},<<String3>>] intrinsic:StringBuilderAppendString loop:<<Loop>>
/// CHECK-DAG: InvokeVirtual [{{l\d+}}] intrinsic:StringBuilderLength loop:none
//
/// CHECK-START: int Main.builderLoopAppender() instruction_simplifier (after)
/// CHECK-DAG: <<New:l\d+>> NewInstance loop:none
/// CHECK-DAG: <<String1:l\d+>> LoadString loop:<<Loop:B\d+>>
/// CHECK-DAG: <<Append1:l\d+>> InvokeVirtual [<<New>>,<<String1>>] intrinsic:StringBuilderAppendString loop:<<Loop>>
/// CHECK-DAG: <<String2:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append2:l\d+>> InvokeVirtual [<<New>>,<<String2>>] intrinsic:StringBuilderAppendString loop:<<Loop>>
/// CHECK-DAG: <<String3:l\d+>> LoadString loop:<<Loop>>
/// CHECK-DAG: <<Append3:l\d+>> InvokeVirtual [<<New>>,<<String3>>] intrinsic:StringBuilderAppendString loop:<<Loop>>
/// CHECK-DAG: InvokeVirtual [<<New>>] intrinsic:StringBuilderLength loop:none
static int builderLoopAppender() {
StringBuilder b = new StringBuilder();
for (int i = 0; i < 10; i++) {
b.append("x").append("y").append("z");
}
return b.length();
}
static int builderLoopAppenderSmali() throws Exception {
Class<?> c = Class.forName("Smali");
Method m = c.getMethod("bufferLoopAppender");
return (Integer) m.invoke(null);
}
//
// All calls in the loop-body and thus loop can be eliminated.
//
/// CHECK-START: int Main.bufferDeadLoop() instruction_simplifier (before)
/// CHECK-DAG: Phi loop:<<Loop:B\d+>>
/// CHECK-DAG: InvokeVirtual intrinsic:StringBufferToString loop:<<Loop>>
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:<<Loop>>
//
/// CHECK-START: int Main.bufferDeadLoop() loop_optimization (after)
/// CHECK-NOT: Phi
/// CHECK-NOT: InvokeVirtual intrinsic:StringBufferToString
/// CHECK-NOT: InvokeVirtual intrinsic:StringStringIndexOfAfter
static int bufferDeadLoop() {
StringBuffer b = new StringBuffer();
String x = "x";
for (int i = 0; i < 10; i++) {
int d = b.toString().indexOf(x, 1);
}
return b.length();
}
//
// All calls in the loop-body and thus loop can be eliminated.
//
/// CHECK-START: int Main.builderDeadLoop() instruction_simplifier (before)
/// CHECK-DAG: Phi loop:<<Loop:B\d+>>
/// CHECK-DAG: InvokeVirtual intrinsic:StringBuilderToString loop:<<Loop>>
/// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:<<Loop>>
//
/// CHECK-START: int Main.builderDeadLoop() loop_optimization (after)
/// CHECK-NOT: Phi
/// CHECK-NOT: InvokeVirtual intrinsic:StringBuilderToString
/// CHECK-NOT: InvokeVirtual intrinsic:StringStringIndexOfAfter
static int builderDeadLoop() {
StringBuilder b = new StringBuilder();
String x = "x";
for (int i = 0; i < 10; i++) {
int d = b.toString().indexOf(x, 1);
}
return b.length();
}
// Regression b/33656359: StringBuffer x is passed to constructor of String
// (this caused old code to crash due to missing nullptr check).
//
/// CHECK-START: void Main.doesNothing() instruction_simplifier (before)
/// CHECK-DAG: InvokeVirtual intrinsic:StringBufferToString
//
/// CHECK-START: void Main.doesNothing() instruction_simplifier (after)
/// CHECK-DAG: InvokeVirtual intrinsic:StringBufferToString
static void doesNothing() {
StringBuffer x = new StringBuffer();
String y = new String(x);
x.toString();
}
public static void main(String[] args) throws Exception {
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));
expectEquals(2, bufferLen2());
expectEquals(2, bufferLen2Smali());
expectEquals(2, builderLen2());
expectEquals(2, builderLen2Smali());
expectEquals(30, bufferLoopAppender());
expectEquals(30, bufferLoopAppenderSmali());
expectEquals(30, builderLoopAppender());
expectEquals(30, builderLoopAppenderSmali());
expectEquals(0, bufferDeadLoop());
expectEquals(0, builderDeadLoop());
doesNothing();
System.out.println("passed");
}
private static void expectEquals(int expected, int result) {
if (expected != result) {
throw new Error("Expected: " + expected + ", found: " + result);
}
}
}
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