jaspex.speculation.InjectDetectLocalClassVisitor.java Source code

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Here is the source code for jaspex.speculation.InjectDetectLocalClassVisitor.java

Source

/*
 * jaspex-mls: a Java Software Speculative Parallelization Framework
 * Copyright (C) 2015 Ivo Anjo <ivo.anjo@ist.utl.pt>
 *
 * This file is part of jaspex-mls.
 *
 * jaspex-mls is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * jaspex-mls 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with jaspex-mls.  If not, see <http://www.gnu.org/licenses/>.
 */

package jaspex.speculation;

import jaspex.ClassFilter;

import asmlib.Type;

import org.objectweb.asm.*;

import static org.objectweb.asm.Opcodes.*;

/** ClassVisitor que adiciona o campo $owner e os mtodos $setOwner / $getOwner, usado pelo suporte
  * para -detectlocal, assim como adiciona $owner = Transaction.current() ao constructor dos objectos.
  *
  * A ideia  que o campo $owner mantm a transaco que criou um objecto, e essa transaco
  * pode aceder directamente ao objecto.
  *
  * Esta alterao apenas  feita ao Objecto top-level de uma hierarquia, ou seja ao objecto cuja
  * superclasse  no-transaccional (Object, ou outra coisa).
  *
  * FIXME: De notar que a implementao actual causa o leak dos $owners, j que nunca so limpos.
  **/
public class InjectDetectLocalClassVisitor extends ClassVisitor {

    private boolean _active;
    private String _name;

    public InjectDetectLocalClassVisitor(ClassVisitor cv) {
        super(Opcodes.ASM4, cv);
    }

    @Override
    public void visit(int version, int access, String name, String signature, String superName,
            String[] interfaces) {
        cv.visit(version, access, name, signature, superName, interfaces);
        _active = jaspex.Options.DETECTLOCAL && ((access & ACC_INTERFACE) == 0)
                && !ClassFilter.isTransactifiable(Type.fromAsm(superName));
        _name = name;
    }

    @Override
    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
        if (_active && name.equals("<init>") && desc.contains("/SpeculativeCtorMarker")) {
            return new MethodVisitor(Opcodes.ASM4, cv.visitMethod(access, name, desc, signature, exceptions)) {
                @Override
                public void visitCode() {
                    mv.visitCode();
                    mv.visitVarInsn(ALOAD, 0);
                    mv.visitMethodInsn(INVOKESTATIC, CommonTypes.TRANSACTION.asmName(), "getOwnerTag",
                            "()" + Type.OBJECT.bytecodeName());
                    mv.visitFieldInsn(PUTFIELD, _name, "$owner", Type.OBJECT.bytecodeName());
                }
            };
        } else {
            return cv.visitMethod(access, name, desc, signature, exceptions);
        }
    }

    @Override
    public void visitEnd() {
        if (_active) {
            cv.visitField(ACC_PUBLIC, "$owner", Type.OBJECT.bytecodeName(), null, null);

            {
                MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, "$setOwner", "(Ljava/lang/Object;)V", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitVarInsn(ALOAD, 1);
                mv.visitFieldInsn(PUTFIELD, _name, "$owner", Type.OBJECT.bytecodeName());
                mv.visitInsn(RETURN);
                mv.visitMaxs(0, 0);
                mv.visitEnd();
            }
            {
                MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, "$getOwner", "()Ljava/lang/Object;", null, null);
                mv.visitCode();
                mv.visitVarInsn(ALOAD, 0);
                mv.visitFieldInsn(GETFIELD, _name, "$owner", Type.OBJECT.bytecodeName());
                mv.visitInsn(ARETURN);
                mv.visitMaxs(1, 1);
                mv.visitEnd();
            }
        }

        cv.visitEnd();
    }

}