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/*
* Copyright (c) 2013, 2015, 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
* @bug 8022186
* @summary javac generates dead code if a try with an empty body has a finalizer
* @modules jdk.jdeps/com.sun.tools.classfile
* jdk.compiler/com.sun.tools.javac.util
*/
import com.sun.tools.classfile.Attribute;
import com.sun.tools.classfile.ClassFile;
import com.sun.tools.classfile.Code_attribute;
import com.sun.tools.classfile.ConstantPool;
import com.sun.tools.classfile.ConstantPool.CONSTANT_String_info;
import com.sun.tools.classfile.ConstantPool.CPInfo;
import com.sun.tools.classfile.ConstantPool.InvalidIndex;
import com.sun.tools.classfile.Instruction;
import com.sun.tools.classfile.Instruction.KindVisitor;
import com.sun.tools.classfile.Instruction.TypeKind;
import com.sun.tools.classfile.Method;
import com.sun.tools.javac.util.Assert;
import java.io.BufferedInputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
public class DeadCodeGeneratedForEmptyTryTest {
public static void main(String[] args) throws Exception {
new DeadCodeGeneratedForEmptyTryTest().run();
}
void run() throws Exception {
checkClassFile(Paths.get(System.getProperty("test.classes"),
this.getClass().getName() + "$Test.class"));
}
int utf8Index;
int numberOfRefToStr = 0;
ConstantPool constantPool;
void checkClassFile(final Path path) throws Exception {
ClassFile classFile = ClassFile.read(
new BufferedInputStream(Files.newInputStream(path)));
constantPool = classFile.constant_pool;
utf8Index = constantPool.getUTF8Index("STR_TO_LOOK_FOR");
for (Method method: classFile.methods) {
if (method.getName(constantPool).equals("methodToLookFor")) {
Code_attribute codeAtt = (Code_attribute)method.attributes.get(Attribute.Code);
for (Instruction inst: codeAtt.getInstructions()) {
inst.accept(codeVisitor, null);
}
}
}
Assert.check(numberOfRefToStr == 1,
"There should only be one reference to a CONSTANT_String_info structure in the generated code");
}
CodeVisitor codeVisitor = new CodeVisitor();
class CodeVisitor implements KindVisitor<Void, Void> {
void checkIndirectRefToString(int cp_index) {
try {
CPInfo cInfo = constantPool.get(cp_index);
if (cInfo instanceof CONSTANT_String_info) {
CONSTANT_String_info strInfo = (CONSTANT_String_info)cInfo;
if (strInfo.string_index == utf8Index) {
numberOfRefToStr++;
}
}
} catch (InvalidIndex ex) {
throw new AssertionError("invalid constant pool index at " + cp_index);
}
}
@Override
public Void visitNoOperands(Instruction instr, Void p) {
return null;
}
@Override
public Void visitArrayType(Instruction instr, TypeKind kind, Void p) {
return null;
}
@Override
public Void visitBranch(Instruction instr, int offset, Void p) {
return null;
}
@Override
public Void visitConstantPoolRef(Instruction instr, int index, Void p) {
checkIndirectRefToString(index);
return null;
}
@Override
public Void visitConstantPoolRefAndValue(Instruction instr, int index, int value, Void p) {
checkIndirectRefToString(index);
return null;
}
@Override
public Void visitLocal(Instruction instr, int index, Void p) {
return null;
}
@Override
public Void visitLocalAndValue(Instruction instr, int index, int value, Void p) {
return null;
}
@Override
public Void visitLookupSwitch(Instruction instr, int default_, int npairs, int[] matches, int[] offsets, Void p) {
return null;
}
@Override
public Void visitTableSwitch(Instruction instr, int default_, int low, int high, int[] offsets, Void p) {
return null;
}
@Override
public Void visitValue(Instruction instr, int value, Void p) {
return null;
}
@Override
public Void visitUnknown(Instruction instr, Void p) {
return null;
}
}
public class Test {
void methodToLookFor() {
try {
} finally {
System.out.println("STR_TO_LOOK_FOR");
}
}
}
}
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