/*
* Copyright (c) 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
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*/
package compiler.calls.common;
import jdk.internal.org.objectweb.asm.ClassReader;
import jdk.internal.org.objectweb.asm.ClassVisitor;
import jdk.internal.org.objectweb.asm.ClassWriter;
import jdk.internal.org.objectweb.asm.Handle;
import jdk.internal.org.objectweb.asm.Label;
import jdk.internal.org.objectweb.asm.MethodVisitor;
import jdk.internal.org.objectweb.asm.Opcodes;
import java.io.FileInputStream;
import java.io.IOException;
import java.lang.invoke.CallSite;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.net.URISyntaxException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;
/**
* A class which patch InvokeDynamic class bytecode with invokydynamic
instruction, rewriting "caller" method to call "callee" method using
invokedynamic
*/
public class InvokeDynamicPatcher extends ClassVisitor {
private static final String CLASS = InvokeDynamic.class.getName()
.replace('.', '/');
private static final String CALLER_METHOD_NAME = "caller";
private static final String CALLEE_METHOD_NAME = "callee";
private static final String NATIVE_CALLEE_METHOD_NAME = "calleeNative";
private static final String BOOTSTRAP_METHOD_NAME = "bootstrapMethod";
private static final String CALL_NATIVE_FIELD = "nativeCallee";
private static final String CALL_NATIVE_FIELD_DESC = "Z";
private static final String CALLEE_METHOD_DESC
= "(L" + CLASS + ";IJFDLjava/lang/String;)Z";
private static final String ASSERTTRUE_METHOD_DESC
= "(ZLjava/lang/String;)V";
private static final String ASSERTS_CLASS = "jdk/test/lib/Asserts";
private static final String ASSERTTRUE_METHOD_NAME = "assertTrue";
public static void main(String args[]) {
ClassReader cr;
Path filePath;
try {
filePath = Paths.get(InvokeDynamic.class.getProtectionDomain().getCodeSource()
.getLocation().toURI()).resolve(CLASS + ".class");
} catch (URISyntaxException ex) {
throw new Error("TESTBUG: Can't get code source" + ex, ex);
}
try (FileInputStream fis = new FileInputStream(filePath.toFile())) {
cr = new ClassReader(fis);
} catch (IOException e) {
throw new Error("Error reading file", e);
}
ClassWriter cw = new ClassWriter(cr,
ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
cr.accept(new InvokeDynamicPatcher(Opcodes.ASM5, cw), 0);
try {
Files.write(filePath, cw.toByteArray(),
StandardOpenOption.WRITE);
} catch (IOException e) {
throw new Error(e);
}
}
public InvokeDynamicPatcher(int api, ClassWriter cw) {
super(api, cw);
}
@Override
public MethodVisitor visitMethod(final int access, final String name,
final String desc, final String signature,
final String[] exceptions) {
/* a code generate looks like
* 0: aload_0
* 1: ldc #125 // int 1
* 3: ldc2_w #126 // long 2l
* 6: ldc #128 // float 3.0f
* 8: ldc2_w #129 // double 4.0d
* 11: ldc #132 // String 5
* 13: aload_0
* 14: getfield #135 // Field nativeCallee:Z
* 17: ifeq 28
* 20: invokedynamic #181, 0 // InvokeDynamic #1:calleeNative:(Lcompiler/calls/common/InvokeDynamic;IJFDLjava/lang/String;)Z
* 25: goto 33
* 28: invokedynamic #183, 0 // InvokeDynamic #1:callee:(Lcompiler/calls/common/InvokeDynamic;IJFDLjava/lang/String;)Z
* 33: ldc #185 // String Call insuccessfull
* 35: invokestatic #191 // Method jdk/test/lib/Asserts.assertTrue:(ZLjava/lang/String;)V
* 38: return
*
* or, using java-like pseudo-code
* if (this.nativeCallee == false) {
* invokedynamic-call-return-value = invokedynamic-of-callee
* } else {
* invokedynamic-call-return-value = invokedynamic-of-nativeCallee
* }
* Asserts.assertTrue(invokedynamic-call-return-value, error-message);
* return;
*/
if (name.equals(CALLER_METHOD_NAME)) {
MethodVisitor mv = cv.visitMethod(access, name, desc,
signature, exceptions);
Label nonNativeLabel = new Label();
Label checkLabel = new Label();
MethodType mtype = MethodType.methodType(CallSite.class,
MethodHandles.Lookup.class, String.class, MethodType.class);
Handle bootstrap = new Handle(Opcodes.H_INVOKESTATIC, CLASS,
BOOTSTRAP_METHOD_NAME, mtype.toMethodDescriptorString());
mv.visitCode();
// push callee parameters onto stack
mv.visitVarInsn(Opcodes.ALOAD, 0);//push "this"
mv.visitLdcInsn(1);
mv.visitLdcInsn(2L);
mv.visitLdcInsn(3.0f);
mv.visitLdcInsn(4.0d);
mv.visitLdcInsn("5");
// params loaded. let's decide what method to call
mv.visitVarInsn(Opcodes.ALOAD, 0); // push "this"
// get nativeCallee field
mv.visitFieldInsn(Opcodes.GETFIELD, CLASS, CALL_NATIVE_FIELD,
CALL_NATIVE_FIELD_DESC);
// if nativeCallee == false goto nonNativeLabel
mv.visitJumpInsn(Opcodes.IFEQ, nonNativeLabel);
// invokedynamic nativeCalleeMethod using bootstrap method
mv.visitInvokeDynamicInsn(NATIVE_CALLEE_METHOD_NAME,
CALLEE_METHOD_DESC, bootstrap);
// goto checkLabel
mv.visitJumpInsn(Opcodes.GOTO, checkLabel);
// label: nonNativeLabel
mv.visitLabel(nonNativeLabel);
// invokedynamic calleeMethod using bootstrap method
mv.visitInvokeDynamicInsn(CALLEE_METHOD_NAME, CALLEE_METHOD_DESC,
bootstrap);
mv.visitLabel(checkLabel);
mv.visitLdcInsn(CallsBase.CALL_ERR_MSG);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, ASSERTS_CLASS,
ASSERTTRUE_METHOD_NAME, ASSERTTRUE_METHOD_DESC, false);
// label: return
mv.visitInsn(Opcodes.RETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
return null;
}
return super.visitMethod(access, name, desc, signature, exceptions);
}
}